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Slovikosky SA, Montgomery RA. Large mammal behavioral defenses induced by the cues of human predation. PNAS NEXUS 2024; 3:pgae382. [PMID: 39282006 PMCID: PMC11398908 DOI: 10.1093/pnasnexus/pgae382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 09/18/2024]
Abstract
Large mammals respond to human hunting via proactive and reactive responses, which can induce subsequent nonconsumptive effects (NCEs). Thus, there is evidence that large mammals exhibit considerable behavioral plasticity in response to human hunting risk. Currently, however, it is unclear which cues of human hunting large mammals may be responding to. We conducted a literature review to quantify the large mammal behavioral responses induced by the cues of human hunting. We detected 106 studies published between 1978 and 2022 of which 34 (32%) included at least one measure of cue, typically visual (n = 26 of 106, 25%) or auditory (n = 11 of 106, 10%). Space use (n = 37 of 106, 35%) and flight (n = 31 of 106, 29%) were the most common behavioral responses studied. Among the 34 studies that assessed at least one cue, six (18%) measured large mammal behavioral responses in relation to proxies of human hunting (e.g. hunting site or season). Only 14% (n = 15 of 106) of the studies quantified an NCE associated with an animal's response to human hunting. Moreover, the association between cues measured and antipredator behaviors is unclear due to a consistent lack of controls. Thus, while human hunting can shape animal populations via consumptive effects, the cues triggering these responses are poorly understood. There hence remains a need to link cues, responses, NCEs, and the dynamics of large mammal populations. Human activities can then be adjusted accordingly to prevent both overexploitation and unintended NCEs in animal populations.
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Affiliation(s)
- Sandy A Slovikosky
- Department of Biology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, United Kingdom
| | - Robert A Montgomery
- Department of Biology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, United Kingdom
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2
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Cloutier Z, Festa-Bianchet M, Pelletier F. Direct and indirect effects of cougar predation on bighorn sheep fitness. Ecology 2024; 105:e4374. [PMID: 39031035 DOI: 10.1002/ecy.4374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 02/05/2024] [Accepted: 04/14/2024] [Indexed: 07/22/2024]
Abstract
Predation has direct effects on prey population dynamics through mortality, and it can induce indirect effects through fear. The indirect effects of predation have been documented experimentally, but few studies have quantified them in nature so that their role in prey population dynamics remains controversial. Given the expanding or reintroduced populations of large predators in many areas, the quantification of indirect effects of predation is crucial. We sought to evaluate the direct and indirect fitness effects of intense cougar (Puma concolor) predation using 48 years of data on marked bighorn sheep (Ovis canadensis) on Ram Mountain, Alberta, Canada. We compared years of intense cougar predation with years with no or occasional cougar predation. We first quantified the effects of predation on neonatal, weaning, and overwinter lamb survival, three metrics potentially affected by direct and indirect effects. We then investigated the possible indirect effects of intense cougar predation on lamb production, female summer mass gain, and lamb mass at weaning. We found strong effects of cougar predation on lamb survival, lamb production, and seasonal mass gain of lambs and adult females. In years with high predation, neonatal, weaning, and overwinter lamb survival declined by 18.4%, 19.7% and 20.8%, respectively. Indirect effects included a 14.2% decline in lamb production. Female summer mass gain decreased by 15.6% and lamb mass at weaning declined by 8.0% in years of intense cougar predation. Our findings bring key insights on the impacts of predation on prey fitness by reporting moderate to large effects on recruitment and illustrate the importance of indirect effects of predation on population dynamics.
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Affiliation(s)
- Zachary Cloutier
- Département de Biologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Marco Festa-Bianchet
- Département de Biologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada
- Centre d'études nordiques, Québec City, Quebec, Canada
| | - Fanie Pelletier
- Département de Biologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada
- Centre d'études nordiques, Québec City, Quebec, Canada
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3
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Ehlers L, Palm E, Herriges J, Bentzen T, Suitor M, Joly K, Millspaugh J, Donnelly P, Gross J, Wells J, Larue B, Hebblewhite M. A taste of space: Remote animal observations and discrete-choice models provide new insights into foraging and density dynamics for a large subarctic herbivore. J Anim Ecol 2024; 93:891-905. [PMID: 38773852 DOI: 10.1111/1365-2656.14109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 04/11/2024] [Indexed: 05/24/2024]
Abstract
Competition for resources and space can drive forage selection of large herbivores from the bite through the landscape scale. Animal behaviour and foraging patterns are also influenced by abiotic and biotic factors. Fine-scale mechanisms of density-dependent foraging at the bite scale are likely consistent with density-dependent behavioural patterns observed at broader scales, but few studies have directly tested this assertion. Here, we tested if space use intensity, a proxy of spatiotemporal density, affects foraging mechanisms at fine spatial scales similarly to density-dependent effects observed at broader scales in caribou. We specifically assessed how behavioural choices are affected by space use intensity and environmental processes using behavioural state and forage selection data from caribou (Rangifer tarandus granti) observed from GPS video-camera collars using a multivariate discrete-choice modelling framework. We found that the probability of eating shrubs increased with increasing caribou space use intensity and cover of Salix spp. shrubs, whereas the probability of eating lichen decreased. Insects also affected fine-scale foraging behaviour by reducing the overall probability of eating. Strong eastward winds mitigated negative effects of insects and resulted in higher probabilities of eating lichen. At last, caribou exhibited foraging functional responses wherein their probability of selecting each food type increased as the availability (% cover) of that food increased. Space use intensity signals of fine-scale foraging were consistent with density-dependent responses observed at larger scales and with recent evidence suggesting declining reproductive rates in the same caribou population. Our results highlight potential risks of overgrazing on sensitive forage species such as lichen. Remote investigation of the functional responses of foraging behaviours provides exciting future applications where spatial models can identify high-quality habitats for conservation.
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Affiliation(s)
- L Ehlers
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, USA
| | - E Palm
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, USA
| | - J Herriges
- Bureau of Land Management, Fairbanks, Alaska, USA
| | - T Bentzen
- Alaska Department of Fish and Game, Fairbanks, Alaska, USA
| | - M Suitor
- Yukon Government, Yukon, Yukon Territory, Canada
| | - K Joly
- National Park Service, Yukon-Charley Rivers National Preserve, Fairbanks, Alaska, USA
| | - J Millspaugh
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, USA
| | - P Donnelly
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, USA
| | - J Gross
- Alaska Department of Fish and Game, Tok, Alaska, USA
| | - J Wells
- Alaska Department of Fish and Game, Tok, Alaska, USA
| | - B Larue
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, USA
| | - M Hebblewhite
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, Montana, USA
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4
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Li F, Zhang T, Zhang Z, Lv T, Yu H, Yu D, Liu C. Predation risk-mediated indirect effects promote submerged plant growth: Implications for lake restoration. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 355:120512. [PMID: 38442660 DOI: 10.1016/j.jenvman.2024.120512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 01/31/2024] [Accepted: 02/26/2024] [Indexed: 03/07/2024]
Abstract
Biological manipulation, involving fish stockings, is commonly used to counteract the deterioration of submerged vegetation in eutrophic lakes. Nevertheless, the non-consumptive effects (NCEs) of stocked carnivorous fish are often overlooked. Using a controlled experimental system, we investigated the NCEs of a native carnivorous fish, snakehead (Channa argus), on two key biological factors, herbivore-dominated grass carp (Ctenopharyngodon idella) and disturbance-dominated loach (Misgurnus anguillicaudatus), influencing submerged plants growth. Additionally, we conducted a meta-analysis on predation risk and primary productivity. The results reveal that predation risk induces oxidative stress damage and affects grass carp growth. Non-significant changes in cortisol and glucose may be linked to predation risk prediction. Simultaneously, predation risk reduces fish feeding and disturbance behavior, relieving pressure on submerged plants to be grazed and disturbed, thereby supporting plant development. The presence of submerged plants, in turn, enhances loach activity and influences water body characteristics through negative feedback. Furthermore, the meta-analysis results indicate the facilitative effect of predation risk on primary producers. Our findings contribute to the understanding of biological manipulation theory. We demonstrate that the predation risk associated with introducing carnivorous fish can promote the growth of submerged plants through behaviorally mediated indirect effects. This highlights the potential utility of predation risk in lake restoration efforts.
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Affiliation(s)
- Fuchao Li
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Tiantian Zhang
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Zhiqiang Zhang
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Tian Lv
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Haihao Yu
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Dan Yu
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Chunhua Liu
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
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5
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Shiratsuru S, Studd EK, Boutin S, Peers MJL, Majchrzak YN, Menzies AK, Derbyshire R, Jung TS, Krebs CJ, Boonstra R, Murray DL. When death comes: linking predator-prey activity patterns to timing of mortality to understand predation risk. Proc Biol Sci 2023; 290:20230661. [PMID: 37192667 PMCID: PMC10188243 DOI: 10.1098/rspb.2023.0661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/21/2023] [Indexed: 05/18/2023] Open
Abstract
The assumption that activity and foraging are risky for prey underlies many predator-prey theories and has led to the use of predator-prey activity overlap as a proxy of predation risk. However, the simultaneous measures of prey and predator activity along with timing of predation required to test this assumption have not been available. Here, we used accelerometry data on snowshoe hares (Lepus americanus) and Canada lynx (Lynx canadensis) to determine activity patterns of prey and predators and match these to precise timing of predation. Surprisingly we found that lynx kills of hares were as likely to occur during the day when hares were inactive as at night when hares were active. We also found that activity rates of hares were not related to the chance of predation at daily and weekly scales, whereas lynx activity rates positively affected the diel pattern of lynx predation on hares and their weekly kill rates of hares. Our findings suggest that predator-prey diel activity overlap may not always be a good proxy of predation risk, and highlight a need for examining the link between predation and spatio-temporal behaviour of predator and prey to improve our understanding of how predator-prey behavioural interactions drive predation risk.
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Affiliation(s)
- Shotaro Shiratsuru
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2R3
| | - Emily K. Studd
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2R3
- Department of Biological Sciences, Thompson Rivers University, Kamloops, British Columbia, Canada V2C 0B8
| | - Stan Boutin
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2R3
| | - Michael J. L. Peers
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2R3
| | - Yasmine N. Majchrzak
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2R3
| | - Allyson K. Menzies
- Department of Natural Resource Sciences, McGill University, St-Anne-de-Bellevue, Québec, Canada H9X 3V9
| | | | - Thomas S. Jung
- Department of Environment, Government of Yukon, Whitehorse, Yukon, Canada
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Charles J. Krebs
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Rudy Boonstra
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Dennis L. Murray
- Department of Biology, Trent University, Peterborough, Ontario, Canada
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6
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Fardell LL, Pavey CR, Dickman CR. Influences of roaming domestic cats on wildlife activity in patchy urban environments. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1123355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Roaming domestic cats (Felis catus) are recognised as a threat to wildlife globally. Yet management of pet cats in urbanised areas is not regularly mandated, and management of feral cats in urbanised areas is rarely implemented. Mounting evidence emphasises the value of urban environments as hot spots of wildlife activity, which as the human population continues to grow may become the best or only habitats available to some wildlife species. Wildlife in urban environments must navigate introduced stressors that can compound with natural stressors. Additional, often novel, predators such as free-roaming pet and feral cats that are prevalent in urban environments could have high nonconsumptive fear/stress impacts on urban wildlife that influence their activity and adversely affect their health and reproduction capabilities, possibly more so than direct predation effects do. Cat roaming activity, particularly that of pet cats, could be managed with the support of the community, though motivation needs to be ensured. Understanding if roaming cat activity influences urban wildlife activity via perceived fear/stress impacts will help to build community motivation for the need for domestic cat management in urbanised areas. Using infrared motion sensor cameras positioned in both yards and green space edge habitats, we observed whether the presence and times active of native and introduced small mammals, and native birds, were impacted by domestic cat activity within a 24-h period and by their activity in the prior-24-h period. We found evidence of cat roaming activity during the hours of most wildlife activity, and show that wildlife navigated “landscapes of fear” relative to cat activity, as wildlife observed across a 24-h period increased their activity in the absence of cats in the same 24-h period and in the previous 24-h period. We also tested if cat activity was relative to previous cat activity, or disturbances, and found that cats reduced activity in response to each, but were still consistently present. Our results provide justification for the need to increase management of domestic cats in urbanised areas and offer fear/stress impacts as a novel approach to engender community support of such management.
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7
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Smith BJ, MacNulty DR, Stahler DR, Smith DW, Avgar T. Density-dependent habitat selection alters drivers of population distribution in northern Yellowstone elk. Ecol Lett 2023; 26:245-256. [PMID: 36573288 PMCID: PMC10107875 DOI: 10.1111/ele.14155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 10/26/2022] [Accepted: 11/02/2022] [Indexed: 12/28/2022]
Abstract
Although it is well established that density dependence drives changes in organismal abundance over time, relatively little is known about how density dependence affects variation in abundance over space. We tested the hypothesis that spatial trade-offs between food and safety can change the drivers of population distribution, caused by opposing patterns of density-dependent habitat selection (DDHS) that are predicted by the multidimensional ideal free distribution. We addressed this using winter aerial survey data of northern Yellowstone elk (Cervus canadensis) spanning four decades. Supporting our hypothesis, we found positive DDHS for food (herbaceous biomass) and negative DDHS for safety (openness and roughness), such that the primary driver of habitat selection switched from food to safety as elk density decreased from 9.3 to 2.0 elk/km2 . Our results demonstrate how population density can drive landscape-level shifts in population distribution, confounding habitat selection inference and prediction and potentially affecting community-level interactions.
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Affiliation(s)
- Brian J Smith
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, Utah, USA
| | - Daniel R MacNulty
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, Utah, USA
| | - Daniel R Stahler
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, Wyoming, USA
| | - Douglas W Smith
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, Wyoming, USA
| | - Tal Avgar
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, Utah, USA.,Biodiversity Pathways Ltd., British Columbia, Canada
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8
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Morris DW. Sex‐dependent habitat selection modulates risk management by meadow voles. Ecosphere 2023. [DOI: 10.1002/ecs2.4378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Affiliation(s)
- Douglas W. Morris
- Department of Biology Lakehead University Thunder Bay Ontario Canada
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9
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Watson F, Becker MS, Smit D, Droge E, Mukula T, Martens S, Mwaba S, Christianson D, Creel S, Brennan A, M'soka J, Gaylard A, Simukonda C, Nyirenda M, Mayani B. Predation strongly limits demography of a keystone migratory herbivore in a recovering transfrontier ecosystem. Ecol Evol 2022; 12:e9414. [PMID: 36262265 PMCID: PMC9575999 DOI: 10.1002/ece3.9414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 08/19/2022] [Accepted: 08/23/2022] [Indexed: 11/20/2022] Open
Abstract
Large herbivore migrations are imperiled globally; however the factors limiting a population across its migratory range are typically poorly understood. Zambia's Greater Liuwa Ecosystem (GLE) contains one of the largest remaining blue wildebeest (Connochaetes taurinus taurinus) migrations, yet the population structure, vital rates, and limiting factors are virtually unknown. We conducted a long-term demographic study of GLE wildebeest from 2012 to 2019 of 107 collared adult females and their calves, 7352 herd observations, 12 aerial population surveys, and concurrent carnivore studies. We applied methods of vital rate estimation and survival analysis within a Bayesian estimation framework. From herd composition observations, we estimated rates of fecundity, first-year survival, and recruitment as 68%, 56%, and 38% respectively, with pronounced interannual variation. Similar rates were estimated from calf-detections with collared cows. Adult survival rates declined steadily from 91% at age 2 years to 61% at age 10 years thereafter dropping more sharply to 2% at age 16 years. Predation, particularly by spotted hyena, was the predominant cause of death for all wildebeest ages and focused on older animals. Starvation only accounted for 0.8% of all unbiased known natural causes of death. Mortality risk differed substantially between wet and dry season ranges, reflecting strong spatio-temporal differences in habitat and predator densities. There was substantial evidence that mortality risk to adults was 27% higher in the wet season, and strong evidence that it was 45% higher in the migratory range where predator density was highest. The estimated vital rates were internally consistent, predicting a stable population trajectory consistent with aerial estimates. From essentially zero knowledge of GLE wildebeest dynamics, this work provides vital rates, age structure, limiting factors, and a plausible mechanism for the migratory tendency, and a robust model-based foundation to evaluate the effects of potential restrictions in migratory range, climate change, predator-prey dynamics, and poaching.
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Affiliation(s)
- Fred Watson
- California State University Monterey BaySeasideCaliforniaUSA
- Zambian Carnivore ProgrammeMfuweZambia
| | - Matthew S. Becker
- Zambian Carnivore ProgrammeMfuweZambia
- Conservation Biology and Ecology Program, Department of EcologyMontana State UniversityBozemanMontanaUSA
| | - Daan Smit
- Zambian Carnivore ProgrammeMfuweZambia
| | - Egil Droge
- Zambian Carnivore ProgrammeMfuweZambia
- Wildlife Conservation Research Unit, The Recanati‐Kaplan Centre, Department of ZoologyUniversity of OxfordOxfordUK
| | - Teddy Mukula
- Zambian Carnivore ProgrammeMfuweZambia
- African Parks Zambia, Liuwa Plain National ParkKalaboZambia
- Worldwide Fund for NatureLusakaZambia
| | | | - Shadrach Mwaba
- Zambian Carnivore ProgrammeMfuweZambia
- Worldwide Fund for NatureLusakaZambia
| | - David Christianson
- Zambian Carnivore ProgrammeMfuweZambia
- Department of Ecosystem Science and ManagementUniversity of WyomingLaramieWyomingUSA
| | - Scott Creel
- Zambian Carnivore ProgrammeMfuweZambia
- Conservation Biology and Ecology Program, Department of EcologyMontana State UniversityBozemanMontanaUSA
- Institutionen för Vilt, Fisk och Miljö, Sveriges LantbruksuniversitetUmeåSweden
| | | | - Jassiel M'soka
- Zambian Carnivore ProgrammeMfuweZambia
- U.S. Agency for International DevelopmentLusakaZambia
| | - Angela Gaylard
- African Parks Zambia, Liuwa Plain National ParkKalaboZambia
| | - Chuma Simukonda
- Zambia Department of National Parks and WildlifeChilangaZambia
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10
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Paterson JT, Proffitt KM, DeCesare NJ, Gude JA, Hebblewhite M. Evaluating the summer landscapes of predation risk and forage quality for elk ( Cervus canadensis). Ecol Evol 2022; 12:e9201. [PMID: 35979523 PMCID: PMC9366754 DOI: 10.1002/ece3.9201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/12/2022] [Accepted: 07/14/2022] [Indexed: 11/25/2022] Open
Abstract
The recovery of carnivore populations in North American has consequences for trophic interactions and population dynamics of prey. In addition to direct effects on prey populations through killing, predators can influence prey behavior by imposing the risk of predation. The mechanisms through which patterns of space use by predators are linked to behavioral response by prey and nonconsumptive effects on prey population dynamics are poorly understood. Our goal was to characterize population- and individual-level patterns of resource selection by elk (Cervus canadensis) in response to risk of wolves (Canis lupus) and mountain lions (Puma concolor) and evaluate potential nonconsumptive effects of these behavioral patterns. We tested the hypothesis that individual elk risk-avoidance behavior during summer would result in exposure to lower-quality forage and reduced body fat and pregnancy rates. First, we evaluated individuals' second-order and third-order resource selection with a used-available sampling design. At the population level, we found evidence for a positive relationship between second- and third-order selection and forage, and an interaction between forage quality and mountain lion risk such that the relative probability of use at low mountain lion risk increased with forage quality but decreased at high risk at both orders of selection. We found no evidence of a population-level trade-off between forage quality and wolf risk. However, we found substantial among-individual heterogeneity in resource selection patterns such that population-level patterns were potentially misleading. We found no evidence that the diversity of individual resource selection patterns varied predictably with available resources, or that patterns of individual risk-related resource selection translated into biologically meaningful changes in body fat or pregnancy rates. Our work highlights the importance of evaluating individual responses to predation risk and predator hunting technique when assessing responses to predators and suggests nonconsumptive effects are not operating at a population scale in this system.
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Affiliation(s)
| | | | | | | | - Mark Hebblewhite
- Department of Ecosystem and Conservation SciencesUniversity of MontanaMissoulaMontanaUSA
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11
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Majchrzak YN, Peers MJL, Studd EK, Menzies AK, Walker PD, Shiratsuru S, McCaw LK, Boonstra R, Humphries M, Jung TS, Kenney AJ, Krebs CJ, Murray DL, Boutin S. Balancing food acquisition and predation risk drives demographic changes in snowshoe hare population cycles. Ecol Lett 2022; 25:981-991. [PMID: 35148018 DOI: 10.1111/ele.13975] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 12/08/2021] [Accepted: 01/04/2022] [Indexed: 11/28/2022]
Abstract
Snowshoe hare cycles are one of the most prominent phenomena in ecology. Experimental studies point to predation as the dominant driving factor, but previous experiments combining food supplementation and predator removal produced unexplained multiplicative effects on density. We examined the potential interactive effects of food limitation and predation in causing hare cycles using an individual-based food-supplementation experiment over-winter across three cycle phases that naturally varied in predation risk. Supplementation doubled over-winter survival with the largest effects occurring in the late increase phase. Although the proximate cause of mortality was predation, supplemented hares significantly decreased foraging time and selected for conifer habitat, potentially reducing their predation risk. Supplemented hares also lost less body mass which resulted in the production of larger leverets. Our results establish a mechanistic link between how foraging time, mass loss and predation risk affect survival and reproduction, potentially driving demographic changes associated with hare cycles.
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Affiliation(s)
- Yasmine N Majchrzak
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Michael J L Peers
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Emily K Studd
- Department of Natural Resource Sciences, McGill University, Montreal, Quebec, Canada
| | - Allyson K Menzies
- Department of Natural Resource Sciences, McGill University, Montreal, Quebec, Canada
| | - Philip D Walker
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Shotaro Shiratsuru
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Laura K McCaw
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Rudy Boonstra
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Murray Humphries
- Department of Natural Resource Sciences, McGill University, Montreal, Quebec, Canada
| | - Thomas S Jung
- Department of Environment, Government of Yukon, Whitehorse, Yukon, Canada.,Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Alice J Kenney
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Charles J Krebs
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dennis L Murray
- Department of Biology, Trent University, Peterborough, Ontario, Canada
| | - Stan Boutin
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
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12
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Weterings MJA, Losekoot S, Kuipers HJ, Prins HHT, van Langevelde F, van Wieren SE. Influence of multiple predators decreases body condition and fecundity of European hares. Ecol Evol 2022; 12:e8442. [PMID: 35136544 PMCID: PMC8809432 DOI: 10.1002/ece3.8442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 11/15/2021] [Accepted: 11/25/2021] [Indexed: 11/08/2022] Open
Abstract
We assessed the hypothesized negative correlation between the influence of multiple predators and body condition and fecundity of the European hare, from 13 areas in the Netherlands.Year-round abundance of predators was estimated by hunters. We quantified predator influence as the sum of their field metabolic rates, as this sum reflects the daily food requirements of multiple individuals. We determined the ratio between body mass and hindfoot length of hares as an index of body condition and the weight of their adrenal gland as a measure of chronic exposure to stress, and we counted the number of placental scars to estimate fecundity of hares.As hypothesized, we found that the sum of field metabolic rate of predators was negatively correlated with body condition and the number of placental scars, whereas it was positively related to the weight of the adrenal glands. In contrast to the sum of the field metabolic rate, the total number of predators did not or weakly affect the investigated risk responses.The sum of the field metabolic rate can be a useful proxy for the influence of multiple predators and takes into account predator abundance, type, body weight, and food requirements of multiple predators.With our findings, our paper contributes to a better understanding of the risk effects of multiple predators on prey fitness. Additionally, we identify a potential contributor to the decline of European hare populations.
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Affiliation(s)
- Martijn J. A. Weterings
- Wildlife Ecology and Conservation GroupWageningen UniversityWageningenThe Netherlands
- Wildlife ManagementDepartment of Animal ManagementVan Hall Larenstein University of Applied SciencesLeeuwardenThe Netherlands
| | - Sanne Losekoot
- Wildlife ManagementDepartment of Animal ManagementVan Hall Larenstein University of Applied SciencesLeeuwardenThe Netherlands
| | - Henry J. Kuipers
- Wildlife ManagementDepartment of Animal ManagementVan Hall Larenstein University of Applied SciencesLeeuwardenThe Netherlands
| | - Herbert H. T. Prins
- Wildlife Ecology and Conservation GroupWageningen UniversityWageningenThe Netherlands
| | - Frank van Langevelde
- Wildlife Ecology and Conservation GroupWageningen UniversityWageningenThe Netherlands
- School of Life SciencesWestville CampusUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Sipke E. van Wieren
- Wildlife Ecology and Conservation GroupWageningen UniversityWageningenThe Netherlands
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13
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Pedersen ÅØ, Beumer LT, Aanes R, Hansen BB. Sea or summit? Wild reindeer spatial responses to changing high‐arctic winters. Ecosphere 2021. [DOI: 10.1002/ecs2.3883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
| | - Larissa T. Beumer
- Fram Centre Norwegian Polar Institute Tromsø 9296 Norway
- Department of Bioscience Aarhus University Roskilde 4000 Denmark
| | - Ronny Aanes
- Fram Centre Norwegian Polar Institute Tromsø 9296 Norway
| | - Brage B. Hansen
- Norwegian Institute for Nature Research Trondheim 7485 Norway
- Department of Biology Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim 7491 Norway
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14
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Fardell LL, Nano CEM, Pavey CR, Dickman CR. Small Prey Animal Habitat Use in Landscapes of Fear: Effects of Predator Presence and Human Activity Along an Urban Disturbance Gradient. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.750094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Human activity can impose additional stressors to wildlife, both directly and indirectly, including through the introduction of predators and influences on native predators. As urban and adjacent environments are becoming increasingly valuable habitat for wildlife, it is important to understand how susceptible taxa, like small prey animals, persist in urban environments under such additional stressors. Here, in order to determine how small prey animals’ foraging patterns change in response to habitat components and distances to predators and human disturbances, we used filmed giving-up density (GUD) trials under natural conditions along an urban disturbance gradient. We then ran further GUD trials with the addition of experimentally introduced stressors of: the odors of domestic cat (Felis catus)/red fox (Vulpes vulpes) as predator cues, light and sound as human disturbance cues, and their combinations. Small mammals were mostly observed foraging in the GUD trials, and to a lesser degree birds. Animals responded to proximity to predators and human disturbances when foraging under natural conditions, and used habitat components differently based on these distances. Along the urban disturbance gradient situation-specific responses were evident and differed under natural conditions compared to additional stressor conditions. The combined predator with human disturbance treatments resulted in responses of higher perceived risk at environments further from houses. Animals at the urban-edge environment foraged more across the whole site under the additional stressor conditions, but under natural conditions perceived less risk when foraging near predators and further from human disturbance (houses). Contrastingly, at the environments further from houses, foraging near human disturbance (paths/roads) when close to a predator was perceived as lower risk, but when foraging under introduced stressor conditions these disturbances were perceived as high risk. We propose that sensory and behavioral mechanisms, and stress exposure best explain our findings. Our results indicate that habitat components could be managed to reduce the impacts of high predation pressure and human activity in disturbed environments.
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15
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Monk JD, Schmitz OJ. Landscapes shaped from the top down: predicting cascading predator effects on spatial biogeochemistry. OIKOS 2021. [DOI: 10.1111/oik.08554] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Julia D. Monk
- School of the Environment, Yale Univ. New Haven CT USA
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16
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Lavergne SG, Krebs CJ, Kenney AJ, Boutin S, Murray D, Palme R, Boonstra R. The impact of variable predation risk on stress in snowshoe hares over the cycle in North America's boreal forest: adjusting to change. Oecologia 2021; 197:71-88. [PMID: 34435235 DOI: 10.1007/s00442-021-05019-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 08/16/2021] [Indexed: 11/26/2022]
Abstract
The boreal forest is one of the world's ecosystems most affected by global climate warming. The snowshoe hare, its predators, and their population dynamics dominate the mammalian component of the North American boreal forest. Our past research has shown the 9-11-year hare cycle to be predator driven, both directly as virtually all hares that die are killed by their predators, and indirectly through sublethal risk effects on hare stress physiology, behavior, and reproduction. We replicated this research over the entire cycle by measuring changes in predation risk expected to drive changes in chronic stress. We examined changes in hare condition and stress axis function using a hormonal challenge protocol in the late winter of 7 years-spanning all phases of the cycle from the increase through to the low (2014-2020). We simultaneously monitored changes in hare abundance as well as those of their primary predators, lynx and coyotes. Despite observing the expected changes in hare-predator numbers over the cycle, we did not see the predicted changes in chronic stress metrics in the peak and decline phases. Thus, the comprehensive physiological signature indicative of chronic predator-induced stress seen from our previous work was not present in this current cycle. We postulate that hares may now be increasingly showing behavior-mediated rather than stress-mediated responses to their predators. We present evidence that increases in primary productivity have affected boreal community structure and function. We speculate that climate change has caused this major shift in the indirect effects of predation on hares.
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Affiliation(s)
- Sophia G Lavergne
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada
| | - Charles J Krebs
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - Alice J Kenney
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - Stan Boutin
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Dennis Murray
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - Rupert Palme
- Department of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Rudy Boonstra
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada.
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17
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Panday P, Pal N, Samanta S, Tryjanowski P, Chattopadhyay J. Dynamics of a stage-structured predator-prey model: cost and benefit of fear-induced group defense. J Theor Biol 2021; 528:110846. [PMID: 34314732 DOI: 10.1016/j.jtbi.2021.110846] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 07/02/2021] [Accepted: 07/22/2021] [Indexed: 11/16/2022]
Abstract
In the predator-prey system, predators can affect the prey population (1) by direct killing and (2) by inducing predation fear, which ultimately force preys to adopt some anti-predator strategies. However, the anti-predator strategy is not the same for all individual preys of different life stages. Also, anti-predator behavior has both cost and benefit, but most of the mathematical models observed the dynamics by incorporating its cost only. In the present study, we formulate a predator-prey model dividing the prey population into two stages: juvenile and adult. We assume that adult preys are only adapting group defense as an anti-predator strategy when they are sensitive to predation. Group defense plays a positive role for adult prey by reducing their predation, but, on the negative side, it simultaneously decreases their reproductive potential. A parameter, anti-predator sensitivity is introduced to interlink both the benefit and cost of group defense. Our result shows that when adult preys are not showing anti-predator behavior, with an increase of maturation rate, the system exhibits a population cycle of abruptly increasing amplitude, which may drive all species of the system to extinction. Anti-predator sensitivity may exclude oscillation through homoclinic bifurcation and avert the prey population for any possible random extinction. Anti-predator sensitivity also decreases the predator population density and produces bistable dynamics. Higher values of anti-predator sensitivity may lead to the extinction of the predator population and benefit adult preys to persist with large population density. Below a threshold value of anti-predator sensitivity, it may possible to retain the predator population in the system by increasing the fear level of the predator. We also observe our fear-induced stage-structured model exhibits interesting and rich dynamical behaviors, various types of bistabilities in different bi-parameter planes. Finally, we discuss the potential impact of our findings.
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Affiliation(s)
- Pijush Panday
- Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, B. T. Road, Kolkata 700108, India
| | - Nikhil Pal
- Department of Mathematics, Visva-Bharati, Santiniketan 731235, India.
| | - Sudip Samanta
- Department of Mathematics, Bankura University, Bankura, West Bengal, India
| | - Piotr Tryjanowski
- Institute of Zoology, Poznan University of Life Sciences, Wojska Polskiego 71C, Poznan 60-625, Poland
| | - Joydev Chattopadhyay
- Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, B. T. Road, Kolkata 700108, India
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18
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Shiratsuru S, Majchrzak YN, Peers MJL, Studd EK, Menzies AK, Derbyshire R, Humphries MM, Krebs CJ, Murray DL, Boutin S. Food availability and long-term predation risk interactively affect antipredator response. Ecology 2021; 102:e03456. [PMID: 34165786 DOI: 10.1002/ecy.3456] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 04/01/2021] [Accepted: 05/13/2021] [Indexed: 11/07/2022]
Abstract
Food availability and temporal variation in predation risk are both important determinants of the magnitude of antipredator responses, but their effects have rarely been examined simultaneously, particularly in wild prey. Here, we determine how food availability and long-term predation risk affect antipredator responses to acute predation risk by monitoring the foraging response of free-ranging snowshoe hares (Lepus americanus) to an encounter with a Canada lynx (Lynx canadensis) in Yukon, Canada, over four winters (2015-2016 to 2018-2019). We examined how this response was influenced by natural variation in long-term predation risk (2-month mortality rate of hares) while providing some individuals with supplemental food. On average, snowshoe hares reduced foraging time up to 10 h after coming into close proximity (≤75 m) with lynx, and reduced foraging time an average of 15.28 ± 7.08 min per lynx encounter. Hares tended to respond more strongly when the distance to lynx was shorter. More importantly, the magnitude of hares' antipredator response to a lynx encounter was affected by the interaction between food-supplementation and long-term predation risk. Food-supplemented hares reduced foraging time more than control hares after a lynx encounter under low long-term risk, but decreased the magnitude of the response as long-term risk increased. In contrast, control hares increased the magnitude of their response as long-term risk increased. Our findings show that food availability and long-term predation risk interactively drive the magnitude of reactive antipredator response to acute predation risk. Determining the factors driving the magnitude of antipredator responses would contribute to a better understanding of the indirect effects of predators on prey populations.
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Affiliation(s)
- Shotaro Shiratsuru
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2R3, Canada
| | - Yasmine N Majchrzak
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2R3, Canada
| | - Michael J L Peers
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2R3, Canada
| | - Emily K Studd
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2R3, Canada.,Department of Natural Resource Sciences, McGill University, St-Anne-de-Bellevue, Québec, H9X 3V9, Canada
| | - Allyson K Menzies
- Department of Natural Resource Sciences, McGill University, St-Anne-de-Bellevue, Québec, H9X 3V9, Canada
| | | | - Murray M Humphries
- Department of Natural Resource Sciences, McGill University, St-Anne-de-Bellevue, Québec, H9X 3V9, Canada
| | - Charles J Krebs
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dennis L Murray
- Department of Biology, Trent University, Peterborough, Ontario, Canada
| | - Stan Boutin
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2R3, Canada
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19
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Grade AM, Lerman SB, Warren PS. Perilous choices: landscapes of fear for adult birds reduces nestling condition across an urban gradient. Ecosphere 2021. [DOI: 10.1002/ecs2.3665] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Aaron M. Grade
- Program in Organismic and Evolutionary Biology University of Massachusetts 160 Holdsworth Way Amherst Massachusetts 01003 USA
| | - Susannah B. Lerman
- USDA Forest Service Northern Research Station 160 Holdsworth Way Amherst Massachusetts 01003 USA
| | - Paige S. Warren
- Department of Environmental Conservation University of Massachusetts 160 Holdsworth Way Amherst Massachusetts 01003 USA
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20
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Bao H, Wang G, Yao Y, Peng Z, Dou H, Jiang G. Warming-driven shifts in ecological control of fish communities in a large northern Chinese lake over 66 years. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 770:144722. [PMID: 33736366 DOI: 10.1016/j.scitotenv.2020.144722] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/19/2020] [Accepted: 12/20/2020] [Indexed: 06/12/2023]
Abstract
Warming, land-use change, and habitat loss are three major threats to aquatic biodiversity worldwide under the influences of anthropogenic disturbances. Positive feedback between warming and bottom-up regulation may cause irreversible ecological regime shifts. Threshold dynamics of interspecific interactions have been rarely studied in freshwater fish communities using threshold community models. Here we use 66 years (1950-2015) of data to link four ecological regime shifts of 9-species fish communities to climatic and land use changes in Lake Hulun, the largest freshwater lake of Northern China. Overfishing caused the collapse of piscivorous fish populations and an ecological regime shift of Lake Hulun in the late 1950s. The first recorded algal bloom of Lake Hulun took place in 1986, with accelerated warming and rapid increases in livestock grazing. The dominance of planktivorous minnow populations reduced fish biodiversity in a nonlinear, threshold manner when annual mean ambient temperature was >0.12 °C. Multivariate environmental vector regression demonstrated that warming, eutrophication, and water-storage reduction (i.e., habitat loss) were related to three ecological regime shifts of Lake Hulun from 1960 to 2015. Multivariate autoregressive models (MAR) did not detect predation by piscivorous fish in Lake Hulun after 1960. Threshold MAR models indicated that dominant minnow populations and other prey fish populations switched from top-down to bottom-up control during the 1980s. Sustained positive feedback between warming, the dominance of planktivorous fish populations, and bottom-up regulation caused predator-prey role reversal, and probably resulted in three regime shifts of Lake Hulun over 56 years. This study provides a comprehensive analysis of ecological regime shifts in Hulun Lake fish communities, and has potential implications for fish species living in similar environments that are subject to global warming, land-use changes, and overfishing.
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Affiliation(s)
- Heng Bao
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, PR China; Feline Research Center, Chinese State Administration of Forestry and Grassland, Harbin 150040, PR China
| | - Guiming Wang
- Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Yunlong Yao
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, PR China
| | - Zitian Peng
- Hulun Lake National Nature Reserve, Hailar, Inner Mongolia Autonomous Region 021008, PR China
| | - Huashan Dou
- Hulun Lake National Nature Reserve, Hailar, Inner Mongolia Autonomous Region 021008, PR China
| | - Guangshun Jiang
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, PR China; Feline Research Center, Chinese State Administration of Forestry and Grassland, Harbin 150040, PR China.
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21
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van der Kolk H, Ens BJ, Frauendorf M, Jongejans E, Oosterbeek K, Bouten W, van de Pol M. Why time‐limited individuals can make populations more vulnerable to disturbance. OIKOS 2021. [DOI: 10.1111/oik.08031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Henk‐Jan van der Kolk
- Dept of Animal Ecology, Netherlands Inst. of Ecology (NIOO‐KNAW) Wageningen the Netherlands
- Centre for Avian Population Studies Wageningen the Netherlands
| | - Bruno J. Ens
- Sovon Dutch Centre for Field Ornithology Sovon‐Texel Den Burg the Netherlands
- Centre for Avian Population Studies Wageningen the Netherlands
| | - Magali Frauendorf
- Dept of Animal Ecology, Netherlands Inst. of Ecology (NIOO‐KNAW) Wageningen the Netherlands
- Centre for Avian Population Studies Wageningen the Netherlands
| | - Eelke Jongejans
- Radboud Univ., Dept of Animal Ecology and Physiology Nijmegen the Netherlands
- Centre for Avian Population Studies Wageningen the Netherlands
| | - Kees Oosterbeek
- Sovon Dutch Centre for Field Ornithology Sovon‐Texel Den Burg the Netherlands
| | - Willem Bouten
- Inst. for Biodiversity and Ecosystem Dynamics, Univ. of Amsterdam Amsterdam the Netherlands
| | - Martijn van de Pol
- Dept of Animal Ecology, Netherlands Inst. of Ecology (NIOO‐KNAW) Wageningen the Netherlands
- Centre for Avian Population Studies Wageningen the Netherlands
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22
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Beltran RS, Kendall-Bar JM, Pirotta E, Adachi T, Naito Y, Takahashi A, Cremers J, Robinson PW, Crocker DE, Costa DP. Lightscapes of fear: How mesopredators balance starvation and predation in the open ocean. SCIENCE ADVANCES 2021; 7:7/12/eabd9818. [PMID: 33731347 PMCID: PMC7968837 DOI: 10.1126/sciadv.abd9818] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 01/27/2021] [Indexed: 05/06/2023]
Abstract
Like landscapes of fear, animals are hypothesized to strategically use lightscapes based on intrinsic motivations. However, longitudinal evidence of state-dependent risk aversion has been difficult to obtain in wild animals. Using high-resolution biologgers, we continuously measured body condition, time partitioning, three-dimensional movement, and risk exposure of 71 elephant seals throughout their 7-month foraging migrations (N = 16,000 seal days). As body condition improved from 21 to 32% fat and daylength declined from 16 to 10 hours, seals rested progressively earlier with respect to sunrise, sacrificing valuable nocturnal foraging hours to rest in the safety of darkness. Seals in superior body condition prioritized safety over energy conservation by resting >100 meters deeper where it was 300× darker. Together, these results provide empirical evidence that marine mammals actively use the three-dimensional lightscape to optimize risk-reward trade-offs based on ecological and physiological factors.
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Affiliation(s)
- Roxanne S Beltran
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, USA.
| | - Jessica M Kendall-Bar
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Enrico Pirotta
- Department of Mathematics and Statistics, Washington State University, Vancouver, WA, USA
- School of Biological, Earth and Environmental Sciences, University College Cork, Cork, Ireland
| | - Taiki Adachi
- School of Biology, University of St Andrews, St Andrews, Fife, Scotland, UK
| | - Yasuhiko Naito
- National Institute of Polar Research, Tachikawa, Tokyo, Japan
| | | | - Jolien Cremers
- Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Patrick W Robinson
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Daniel E Crocker
- Department of Biology, Sonoma State University, Rohnert Park, CA, USA
| | - Daniel P Costa
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, USA
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23
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Fardell LL, Bedoya-Pérez MA, Dickman CR, Crowther MS, Pavey CR, Narayan EJ. Are physiological and behavioural responses to stressors displayed concordantly by wild urban rodents? Naturwissenschaften 2021; 108:5. [PMID: 33411125 PMCID: PMC7790802 DOI: 10.1007/s00114-020-01716-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 12/09/2020] [Accepted: 12/21/2020] [Indexed: 10/27/2022]
Abstract
Understanding wild animal responses to stressors underpins effective wildlife management. In order for responses to stressors to be correctly interpreted, it is critical that measurements are taken on wild animals using minimally invasive techniques. Studies investigating wild animal responses to stressors often measure either a single physiological or behavioural variable, but whether such responses are comparable and concordant remains uncertain. We investigated this question in a pilot study that measured responses of wild-caught urban brown and black rats (Rattus norvegicus, Rattus rattus) to fur-based olfactory cues from a predator, the domestic cat (Felis catus); a novel herbivore, the koala (Phascolarctos cinereus); and a familiar herbivore and competitor, the common brushtail possum (Trichosurus vulpecula). Physiological responses, measured by assaying faecal glucocorticoid metabolites, were compared to behavioural responses observed via video recordings. We found that physiological and behavioural responses to stressors were expressed concordantly. There was no sizeable physiological response observed, and the behavioural response when considered across the night was negligible. However, the behavioural response to the predator and competitor cues changed across the observation period, with activity increasing with increasing hours of exposure. Our results indicate that responses of wild rodents to cues are nuanced, with stress responses modulated by behaviour changes that vary over time according to the severity of the perceived threat as animals gather further information. If the physiological response alone had been assessed, this moderated response may not have been evident, and in terms of wildlife management, vital information would have been lost.
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Affiliation(s)
- Loren L Fardell
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, 2006, Australia.
| | - Miguel A Bedoya-Pérez
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, 2006, Australia.,School of Psychology, The University of Sydney, Sydney, New South Wales, 2006, Australia.,Brain and Mind Centre, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Christopher R Dickman
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Mathew S Crowther
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Chris R Pavey
- CSIRO, Land and Water, PMB 44, Winnellie, Northern Territory, 0822, Australia
| | - Edward J Narayan
- School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland, Australia
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24
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Loosen AE, Devineau O, Zimmermann B, Cromsigt JPGM, Pfeffer SE, Skarpe C, Marie Mathisen K. Roads, forestry, and wolves interact to drive moose browsing behavior in Scandinavia. Ecosphere 2021. [DOI: 10.1002/ecs2.3358] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Anne E. Loosen
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology Inland Norway University of Applied Sciences Campus Evenstad Koppang2480Norway
| | - Olivier Devineau
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology Inland Norway University of Applied Sciences Campus Evenstad Koppang2480Norway
| | - Barbara Zimmermann
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology Inland Norway University of Applied Sciences Campus Evenstad Koppang2480Norway
| | - Joris P. G. M. Cromsigt
- Department of Wildlife, Fish and Environmental Studies Swedish University of Agricultural Sciences Skogsmarksgränd Umeå901 83Sweden
- Department of Zoology Centre for African Conservation Ecology Nelson Mandela University PO Box 77000 Port Elizabeth6031South Africa
| | - Sabine E. Pfeffer
- Department of Wildlife, Fish and Environmental Studies Swedish University of Agricultural Sciences Skogsmarksgränd Umeå901 83Sweden
| | - Christina Skarpe
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology Inland Norway University of Applied Sciences Campus Evenstad Koppang2480Norway
| | - Karen Marie Mathisen
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology Inland Norway University of Applied Sciences Campus Evenstad Koppang2480Norway
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25
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Davies AB, Cromsigt JPGM, Tambling CJ, le Roux E, Vaughn N, Druce DJ, Marneweck DG, Asner GP. Environmental controls on African herbivore responses to landscapes of fear. OIKOS 2020. [DOI: 10.1111/oik.07559] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Andrew B. Davies
- Dept of Organismic and Evolutionary Biology, Harvard Univ. Cambridge MA USA
- Center for Global Discovery and Conservation Science, Arizona State Univ. Tempe AZ USA
| | - Joris P. G. M. Cromsigt
- Dept of Wildlife, Fish and Environmental Studies, Swedish Univ. of Agricultural Sciences Umeå Sweden
- Dept of Zoology, Centre for African Conservation Ecology, Nelson Mandela Univ. Port Elizabeth South Africa
| | - Craig J. Tambling
- Dept of Zoology, Centre for African Conservation Ecology, Nelson Mandela Univ. Port Elizabeth South Africa
- Dept of Zoology and Entomology, Univ. of Fort Hare Alice South Africa
| | - Elizabeth le Roux
- Dept of Zoology, Centre for African Conservation Ecology, Nelson Mandela Univ. Port Elizabeth South Africa
| | - Nicholas Vaughn
- Center for Global Discovery and Conservation Science, Arizona State Univ. Tempe AZ USA
| | - Dave J. Druce
- Ecological Advice, Ezemvelo KZN Wildlife Hluhluwe‐iMfolozi Park South Africa
- School of Life Sciences, Univ. of KwaZulu‐Natal Pietermaritzburg South Africa
| | - David G. Marneweck
- Eugène Marais Chair of Wildlife Management, Mammal Research Inst., Dept of Zoology and Entomology, Univ. of Pretoria Pretoria South Africa
- Wildlife Ecology Lab, School of Natural Resource Management, Nelson Mandela Univ. Port Elizabeth South Africa
| | - Gregory P. Asner
- Center for Global Discovery and Conservation Science, Arizona State Univ. Tempe AZ USA
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26
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Guo H, Hegab IM, Tan Y, Yao B, Wang C, Cai Z, Ji W, Su J. Exposure to eagle owl feces induces anti-predator behavior, physiology, and hypothalamic gene responses in a subterranean rodent, the plateau zokor (Eospalax baileyi). Behav Ecol Sociobiol 2020. [DOI: 10.1007/s00265-020-02934-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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27
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Wirsing AJ, Heithaus MR, Brown JS, Kotler BP, Schmitz OJ. The context dependence of non-consumptive predator effects. Ecol Lett 2020; 24:113-129. [PMID: 32990363 DOI: 10.1111/ele.13614] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 01/10/2023]
Abstract
Non-consumptive predator effects (NCEs) are now widely recognised for their capacity to shape ecosystem structure and function. Yet, forecasting the propagation of these predator-induced trait changes through particular communities remains a challenge. Accordingly, focusing on plasticity in prey anti-predator behaviours, we conceptualise the multi-stage process by which predators trigger direct and indirect NCEs, review and distil potential drivers of contingencies into three key categories (properties of the prey, predator and setting), and then provide a general framework for predicting both the nature and strength of direct NCEs. Our review underscores the myriad factors that can generate NCE contingencies while guiding how research might better anticipate and account for them. Moreover, our synthesis highlights the value of mapping both habitat domains and prey-specific patterns of evasion success ('evasion landscapes') as the basis for predicting how direct NCEs are likely to manifest in any particular community. Looking ahead, we highlight two key knowledge gaps that continue to impede a comprehensive understanding of non-consumptive predator-prey interactions and their ecosystem consequences; namely, insufficient empirical exploration of (1) context-dependent indirect NCEs and (2) the ways in which direct and indirect NCEs are shaped interactively by multiple drivers of context dependence.
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Affiliation(s)
- Aaron J Wirsing
- School of Environmental and Forest Sciences, University of Washington, Box 352100, Seattle, WA, 98195, USA
| | - Michael R Heithaus
- Department of Biological Sciences, Marine Sciences Program, Florida International University, 3000 NE 151st St, North Miami, FL, 33181, USA
| | - Joel S Brown
- Department of Biological Sciences, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA.,Department of Integrated Mathematical Oncology, Moffitt Cancer Center, 12902 Magnolia Dr, Tampa, FL, 33613, USA
| | - Burt P Kotler
- Mitrani Department of Desert Ecology, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet, Ben-Gurion, 84990, Israel
| | - Oswald J Schmitz
- School of Forestry and Environmental Studies, Yale University, 195 Prospect Street, New Haven, CT, 06511, USA
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28
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Physiological Stress Integrates Resistance to Rattlesnake Venom and the Onset of Risky Foraging in California Ground Squirrels. Toxins (Basel) 2020; 12:toxins12100617. [PMID: 32992585 PMCID: PMC7601495 DOI: 10.3390/toxins12100617] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/22/2020] [Accepted: 09/23/2020] [Indexed: 12/17/2022] Open
Abstract
Using venom for predation often leads to the evolution of resistance in prey. Understanding individual variation in venom resistance is key to unlocking basic mechanisms by which antagonistic coevolution can sustain variation in traits under selection. For prey, the opposing challenges of predator avoidance and resource acquisition often lead to correlated levels of risk and reward, which in turn can favor suites of integrated morphological, physiological and behavioral traits. We investigate the relationship between risk-sensitive behaviors, physiological resistance to rattlesnake venom, and stress in a population of California ground squirrels. For the same individuals, we quantified foraging decisions in the presence of snake predators, fecal corticosterone metabolites (a measure of “stress”), and blood serum inhibition of venom enzymatic activity (a measure of venom resistance). Individual responses to snakes were repeatable for three measures of risk-sensitive behavior, indicating that some individuals were consistently risk-averse whereas others were risk tolerant. Venom resistance was lower in squirrels with higher glucocorticoid levels and poorer body condition. Whereas resistance failed to predict proximity to and interactions with snake predators, individuals with higher glucocorticoid levels and in lower body condition waited the longest to feed when near a snake. We compared alternative structural equation models to evaluate alternative hypotheses for the relationships among stress, venom resistance, and behavior. We found support for stress as a shared physiological correlate that independently lowers venom resistance and leads to squirrels that wait longer to feed in the presence of a snake, whereas we did not find evidence that resistance directly facilitates latency to forage. Our findings suggest that stress may help less-resistant squirrels avoid a deadly snakebite, but also reduces feeding opportunities. The combined lethal and non-lethal effects of stressors in predator–prey interactions simultaneously impact multiple key traits in this system, making environmental stress a potential contributor to geographic variation in trait expression of toxic predators and resistant prey.
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29
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Polivka CM. Habitat affinity and density‐dependent movement as indicators of fish habitat restoration efficacy. Ecosphere 2020. [DOI: 10.1002/ecs2.3166] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Carlos M. Polivka
- Pacific Northwest Research Station USDA Forest Service Wenatchee Washington98801USA
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30
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Hurley MA, Hebblewhite M, Gaillard J. Competition for safe real estate, not food, drives density-dependent juvenile survival in a large herbivore. Ecol Evol 2020; 10:5464-5475. [PMID: 32607167 PMCID: PMC7319175 DOI: 10.1002/ece3.6289] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 02/28/2020] [Accepted: 03/21/2020] [Indexed: 12/04/2022] Open
Abstract
Density-dependent competition for food reduces vital rates, with juvenile survival often the first to decline. A clear prediction of food-based, density-dependent competition for large herbivores is decreasing juvenile survival with increasing density. However, competition for enemy-free space could also be a significant mechanism for density dependence in territorial species. How juvenile survival is predicted to change across density depends critically on the nature of predator-prey dynamics and spatial overlap among predator and prey, especially in multiple-predator systems. Here, we used a management experiment that reduced densities of a generalist predator, coyotes, and specialist predator, mountain lions, over a 5-year period to test for spatial density dependence mediated by predation on juvenile mule deer in Idaho, USA. We tested the spatial density-dependence hypothesis by tracking the fate of 251 juvenile mule deer, estimating cause-specific mortality, and testing responses to changes in deer density and predator abundance. Overall juvenile mortality did not increase with deer density, but generalist coyote-caused mortality did, but not when coyote density was reduced experimentally. Mountain lion-caused mortality did not change with deer density in the reference area in contradiction of the food-based competition hypothesis, but declined in the treatment area, opposite to the pattern of coyotes. These observations clearly reject the food-based density-dependence hypothesis for juvenile mule deer. Instead, our results provide support for the spatial density-dependence hypothesis that competition for enemy-free space increases predation by generalist predators on juvenile large herbivores.
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Affiliation(s)
| | - Mark Hebblewhite
- Wildlife Biology ProgramDepartment of Ecosystem Sciences and ConservationW.A. Franke College of Forestry and ConservationUniversity of MontanaMissoulaMTUSA
| | - Jean‐Michel Gaillard
- Laboratoire Biométrie & Biologie ÉvolutiveCNRSUMR‐CNRS 5558University Claude Bernard ‐ Lyon IVilleurbanne CedexFrance
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31
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Fardell LL, Pavey CR, Dickman CR. Fear and stressing in predator-prey ecology: considering the twin stressors of predators and people on mammals. PeerJ 2020; 8:e9104. [PMID: 32391213 PMCID: PMC7196326 DOI: 10.7717/peerj.9104] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 04/09/2020] [Indexed: 12/28/2022] Open
Abstract
Predators induce stress in prey and can have beneficial effects in ecosystems, but can also have negative effects on biodiversity if they are overabundant or have been introduced. The growth of human populations is, at the same time, causing degradation of natural habitats and increasing interaction rates of humans with wildlife, such that conservation management routinely considers the effects of human disturbance as tantamount to or surpassing those of predators. The need to simultaneously manage both of these threats is particularly acute in urban areas that are, increasingly, being recognized as global hotspots of wildlife activity. Pressures from altered predator-prey interactions and human activity may each initiate fear responses in prey species above those that are triggered by natural stressors in ecosystems. If fear responses are experienced by prey at elevated levels, on top of responses to multiple environmental stressors, chronic stress impacts may occur. Despite common knowledge of the negative effects of stress, however, it is rare that stress management is considered in conservation, except in intensive ex situ situations such as in captive breeding facilities or zoos. We propose that mitigation of stress impacts on wildlife is crucial for preserving biodiversity, especially as the value of habitats within urban areas increases. As such, we highlight the need for future studies to consider fear and stress in predator-prey ecology to preserve both biodiversity and ecosystem functioning, especially in areas where human disturbance occurs. We suggest, in particular, that non-invasive in situ investigations of endocrinology and ethology be partnered in conservation planning with surveys of habitat resources to incorporate and reduce the effects of fear and stress on wildlife.
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Affiliation(s)
- Loren L. Fardell
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
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32
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Owen‐Smith N, Hopcraft G, Morrison T, Chamaillé‐Jammes S, Hetem R, Bennitt E, Van Langevelde F. Movement ecology of large herbivores in African savannas: current knowledge and gaps. Mamm Rev 2020. [DOI: 10.1111/mam.12193] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Norman Owen‐Smith
- Centre for African Ecology School of Animal, Plant and Environmental Sciences University of the Witwatersrand Wits 2050 South Africa
| | - Grant Hopcraft
- Institute of Biodiversity, Animal Health and Comparative Medicine University of Glasgow Glasgow G12 8QQ UK
| | - Thomas Morrison
- Institute of Biodiversity, Animal Health and Comparative Medicine University of Glasgow Glasgow G12 8QQ UK
| | | | - Robyn Hetem
- School of Animal, Plant and Environmental Sciences University of the Witwatersrand Wits 2050 South Africa
| | - Emily Bennitt
- Okavango Research Institute University of Botswana Maun Botswana
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33
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Heissenberger S, de Pinho GM, Martin JGA, Blumstein DT. Age and location influence the costs of compensatory and accelerated growth in a hibernating mammal. Behav Ecol 2020. [DOI: 10.1093/beheco/araa013] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
The increase of structural growth rates to compensate for a poor initial body condition, defined as compensatory growth, may have physiological costs, but little is known about its effects on individual fitness in the wild. Yellow-bellied marmots (Marmota flaviventer) are obligate hibernators and depend on fat accumulation acquired during an approximately 4-month summer to survive overwinter. We investigated the costs of survival and longevity of rapid growth in a wild population of yellow-bellied marmots. We used trapping data collected from 2002 to 2014 to calculate individual relative seasonal growth and assess its effects on longevity and annual survival of juveniles, yearlings, and adults. Sites were distributed in two main areas, down-valley and up-valley; the latter has a higher elevation and is an overall harsher environment. We found that relative seasonal growth had no effect on individual longevity or on juvenile and adult annual survival. For yearlings, the effect of relative seasonal growth on survival depended on the location: yearlings with high relative seasonal growth had lower survival if located up-valley, and higher survival if located down-valley. In conclusion, juveniles and adults do not appear to have detectable costs of rapid growth, although there are costs to yearling survival depending on environmental conditions. Substantial structural growth occurs when marmots are yearlings and our results are likely driven by the high conflicting demands of somatic growth versus maintenance at this stage. Thus, the costs of rapid growth are age and site dependent and may be seen in the short term for species facing temporal constraints on growth.
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Affiliation(s)
| | | | | | - Daniel T Blumstein
- Rocky Mountain Biological Laboratory, Crested Butte, CO, USA
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, USA
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34
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Abstract
AbstractTourists approaching wild animals can potentially cause disturbance as a result of the perceived predation risk. Risk effects arise when prey alter their behaviour in response to predators. This response may carry costs through its impact on fitness-related activities such as foraging. We recorded behavioural responses of whale sharks Rhincodon typus to experimental vessel and swimmer approaches. We simulated the disturbance caused by ecotourism in the foraging site of this planktivorous fish in Bahia de Los Angeles, Gulf of Baja California, Mexico. Stress-related behaviours (vigilance, change of direction, diving and acceleration) were more common directly after both types of disturbance than before, in particular after approach by a swimmer. Individuals were more likely to be vigilant when they were new to the bay, but we did not find evidence of within-season behavioural habituation. Sharks were 24% more likely to forage before human stimuli than after. Our study highlights negative effects of vessel and swimmer approaches on whale shark behaviour, with a short-term increase in stress-related behaviours potentially carrying energetic costs, combined with a decrease in food intake following the disturbance. Our results indicate concerns about the impact of ecotourism on large fish species. An important next step would be to determine whether these short-term behavioural responses to the perception of predation risk negatively affect fitness. Among other guidelines, we recommend preventing swimmers from approaching if whale sharks stop feeding when a vessel approaches.
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35
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Beukes M, Radloff FG, Ferreira SM. Spatial and Seasonal Variation in Lion (Panthera leo) Diet in the Southwestern Kgalagadi Transfrontier Park. AFRICAN JOURNAL OF WILDLIFE RESEARCH 2020. [DOI: 10.3957/056.050.0055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Maya Beukes
- Department of Conservation and Marine Sciences, Faculty of Applied Sciences, Cape Peninsula University of Technology, P.O. Box 652, Cape Town, 8000 South Africa
| | - Frans G.T. Radloff
- Department of Conservation and Marine Sciences, Faculty of Applied Sciences, Cape Peninsula University of Technology, P.O. Box 652, Cape Town, 8000 South Africa
| | - Sam M. Ferreira
- Scientific Services Department, South African National Parks, Skukuza, South Africa
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36
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Dulude‐de Broin F, Hamel S, Mastromonaco GF, Côté SD. Predation risk and mountain goat reproduction: Evidence for stress‐induced breeding suppression in a wild ungulate. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13514] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Frédéric Dulude‐de Broin
- Département de biologie Université Laval Québec City QC Canada
- Centre d'études nordiquesQuébec City QC Canada
| | - Sandra Hamel
- Département de biologie Université Laval Québec City QC Canada
- Department of Arctic and Marine Biology Faculty of Biosciences, Fisheries, and Economics UiT The Arctic University of Norway Tromsø Norway
| | | | - Steeve D. Côté
- Département de biologie Université Laval Québec City QC Canada
- Centre d'études nordiquesQuébec City QC Canada
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37
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Katani R, Schilling MA, Lyimo B, Tonui T, Cattadori IM, Eblate E, Martin A, Estes AB, Buza T, Rentsch D, Davenport KW, Hovde BT, Lyimo S, Munuo L, Stomeo F, Tiambo C, Radzio-Basu J, Mosha F, Hudson PJ, Buza JJ, Kapur V. Microbial Diversity in Bushmeat Samples Recovered from the Serengeti Ecosystem in Tanzania. Sci Rep 2019; 9:18086. [PMID: 31792246 PMCID: PMC6888819 DOI: 10.1038/s41598-019-53969-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 11/05/2019] [Indexed: 01/01/2023] Open
Abstract
Bushmeat, the meat and organs derived from wildlife species, is a common source of animal protein in the diets of those living in sub-Saharan Africa and is frequently associated with zoonotic spillover of dangerous pathogens. Given the frequent consumption of bushmeat in this region and the lack of knowledge about the microbial communities associated with this meat, the microbiome of 56 fresh and processed bushmeat samples ascertained from three districts in the Western Serengeti ecosystem in Tanzania was characterized using 16S rRNA metagenomic sequencing. The results show that the most abundant phyla present in bushmeat samples include Firmicutes (67.8%), Proteobacteria (18.4%), Cyanobacteria (8.9%), and Bacteroidetes (3.1%). Regardless of wildlife species, sample condition, season, or region, the microbiome is diverse across all samples, with no significant difference in alpha or beta diversity. The findings also suggest the presence of DNA signatures of potentially dangerous zoonotic pathogens, including those from the genus Bacillus, Brucella, Coxiella, and others, in bushmeat. Together, this investigation provides a better understanding of the microbiome associated with this major food source in samples collected from the Western Serengeti in Tanzania and highlights a need for future investigations on the potential health risks associated with the harvesting, trade, and consumption of bushmeat in Sub-Saharan Africa.
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Affiliation(s)
- Robab Katani
- Applied Biological and Biosecurity Research Laboratory, Pennsylvania State University, University Park, Pennsylvania, USA.,The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Megan A Schilling
- The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA.,Department of Animal Science, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Beatus Lyimo
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Triza Tonui
- Biosciences eastern and central Africa-International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Isabella M Cattadori
- The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA.,Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Ernest Eblate
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania.,Tanzania Wildlife Research Institute, Arusha, Tanzania
| | - Andimile Martin
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Anna B Estes
- The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA.,Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Teresia Buza
- The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | | | | | - Blake T Hovde
- Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Samson Lyimo
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Lydia Munuo
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Francesca Stomeo
- Biosciences eastern and central Africa-International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Christian Tiambo
- Biosciences eastern and central Africa-International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Jessica Radzio-Basu
- Applied Biological and Biosecurity Research Laboratory, Pennsylvania State University, University Park, Pennsylvania, USA.,The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Fausta Mosha
- Ministry of Health Community Development Gender Elderly and Children, Dar es Salaam, Tanzania
| | - Peter J Hudson
- Applied Biological and Biosecurity Research Laboratory, Pennsylvania State University, University Park, Pennsylvania, USA.,The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Joram J Buza
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Vivek Kapur
- Applied Biological and Biosecurity Research Laboratory, Pennsylvania State University, University Park, Pennsylvania, USA. .,The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA. .,Department of Animal Science, Pennsylvania State University, University Park, Pennsylvania, USA. .,Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania.
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38
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Benson C, Shea B, de Silva C, Donovan D, Holder P, Cooke S, Gallagher A. Physiological consequences of varying large shark exposure on striped bass (Morone saxatilis). CAN J ZOOL 2019. [DOI: 10.1139/cjz-2019-0173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Large marine predators often aggregate seasonally in discrete locations to take advantage of optimal foraging conditions, leading to spatial and temporal variation in their exposure on other species. However, our understanding of the impacts this exposure may have on the behavior and physiology of prey is poor, especially in marine systems. Here, we evaluated the non-consumptive effects of potential exposure to large sharks (white sharks, Carcharodon carcharias (Linnaeus, 1758)) on the stress physiology of an economically important teleost, the striped bass (Morone saxatilis (Walbaum, 1792)), off Cape Cod, Massachusetts, USA. We sampled fish in habitats that varied significantly in shark exposure across 5 months and over 2 years, evaluating blood physiology stress indicators (i.e., cortisol, glucose, and lactate concentrations) and reflex impairment. None of the blood parameters were influenced by shark exposure, although we did observe subtle temperature and seasonal effects. One of the three reflex tests (the vertical orientation test) was negatively affected by shark exposure, although the mechanistic basis for this finding is unclear. This work supports the notion that predictable sources of predation pressure tend not to manifest in stress-related costs in free-ranging prey, which has implications for shaping our understanding of how large sharks influence ecosystems through non-consumptive effects.
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Affiliation(s)
- C.W. Benson
- Beneath the Waves, P.O. Box 126, Herndon, VA 20172, USA
- Three Seas Program, Northeastern University, 430 Nahant Road, MA 01908, USA
| | - B.D. Shea
- Beneath the Waves, P.O. Box 126, Herndon, VA 20172, USA
- Three Seas Program, Northeastern University, 430 Nahant Road, MA 01908, USA
| | - C. de Silva
- Beneath the Waves, P.O. Box 126, Herndon, VA 20172, USA
| | - D. Donovan
- Thayer Academy, 745 Washington Street, Braintree, MA 02184, USA
| | - P.E. Holder
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - S.J. Cooke
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - A.J. Gallagher
- Beneath the Waves, P.O. Box 126, Herndon, VA 20172, USA
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
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39
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Califf KJ, Green DS, Wagner AP, Scribner KT, Beatty K, Wagner ME, Holekamp KE. Genetic relatedness and space use in two populations of striped hyenas (Hyaena hyaena). J Mammal 2019. [DOI: 10.1093/jmammal/gyz165] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Surprising social complexity and variability have recently been documented in several mammalian species once believed to be strictly solitary, and variation in resource abundance may drive this variation in sociality. Wagner et al. (Wagner, A. P., S. Creel, L. G. Frank, and S. T. Kalinowski. 2007. Patterns of relatedness and parentage in an asocial, polyandrous striped hyena population. Molecular Ecology 16:4356–4369) reported unusual space-use patterns among female striped hyenas (Hyaena hyaena) in central Kenya, where pairwise relatedness among females increased with the geographic distance separating them. The authors suggested that this pattern, very rare among mammals, might reflect attempts by females to avoid competition with close relatives for scarce resources in areas of range overlap. Here, we compare those data to new data, documenting genetic relatedness and space use in a previously unstudied wild population of striped hyenas in southern Kenya. We tested hypotheses suggesting that resource abundance and population density affect patterns of genetic relatedness and geographic distance in this species. Our results suggest that higher per capita prey density results in relaxed competition for food, and greater social tolerance among female striped hyenas. A hypothesis suggesting lower population density in the southern population was not supported. Relaxed resource competition also may lead to female–female cooperation in the southern population; we documented for the first time behavioral evidence of den sharing by adult female striped hyenas. Our data indicate that different populations of this little-studied species exhibit behavioral plasticity; in this case, markedly different space-use patterns and patterns of spatial relatedness under different ecological conditions.
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Affiliation(s)
- Katy J Califf
- Department of Integrative Biology and Interdisciplinary Program in Ecology and Evolutionary Biology and Behavior, East Lansing, MI, USA (KJC, DSG, APW, KTS, KEH)
| | - David S Green
- Department of Integrative Biology and Interdisciplinary Program in Ecology and Evolutionary Biology and Behavior, East Lansing, MI, USA (KJC, DSG, APW, KTS, KEH)
| | - Aaron P Wagner
- Department of Integrative Biology and Interdisciplinary Program in Ecology and Evolutionary Biology and Behavior, East Lansing, MI, USA (KJC, DSG, APW, KTS, KEH)
- The BEACON Center for the Study of Evolution in Action, East Lansing, MI, USA (APW, KTS, KEH)
| | - Kim T Scribner
- Department of Integrative Biology and Interdisciplinary Program in Ecology and Evolutionary Biology and Behavior, East Lansing, MI, USA (KJC, DSG, APW, KTS, KEH)
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA
- The BEACON Center for the Study of Evolution in Action, East Lansing, MI, USA (APW, KTS, KEH)
| | - Karen Beatty
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA
| | - Meredith E Wagner
- School of Natural Resources and Environment, University of Florida, Gainesville, FL, USA (MEW)
| | - Kay E Holekamp
- Department of Integrative Biology and Interdisciplinary Program in Ecology and Evolutionary Biology and Behavior, East Lansing, MI, USA (KJC, DSG, APW, KTS, KEH)
- The BEACON Center for the Study of Evolution in Action, East Lansing, MI, USA (APW, KTS, KEH)
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40
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Morosinotto C, Thomson RL, Korpimäki E, Mateo R, Ruuskanen S. Maternal food supplementation and perceived predation risk modify egg composition and eggshell traits but not offspring condition. ACTA ACUST UNITED AC 2019; 222:jeb.201954. [PMID: 31548290 DOI: 10.1242/jeb.201954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 09/16/2019] [Indexed: 11/20/2022]
Abstract
Mothers may vary resource allocation to eggs and embryos, which may affect offspring fitness and prepare them for future environmental conditions. The effects of food availability and predation risk on reproduction have been extensively studied, yet their simultaneous impacts on reproductive investment and offspring early life conditions are still unclear. We experimentally manipulated these key environmental elements using a 2×2 full factorial design in wild, free-living pied flycatchers (Ficedula hypoleuca), and measured egg composition, eggshell traits and offspring condition. Eggs laid in food-supplemented nests had larger yolks and thicker shells independently of predation risk, while eggs laid in nests exposed to predator cues had lower levels of immunoglobulins, independent of food supplementation. In nests without predator cues, shell biliverdin content was higher in eggs laid in food-supplemented nests. Incubation was 1 day shorter in food-supplemented nests and shorter incubation periods were associated with higher hatching success, but there were no direct effects of maternal treatment on hatching success. To investigate the impact of maternal treatment (via egg composition) on the offspring, we performed full brood cross-fostering after hatching to unmanipulated nests. Maternal treatment did not significantly affect body mass and immunoglobulin levels of offspring. Our results suggest that although prenatal maternal cues affected egg composition, these egg-mediated effects may not have detectable consequences for offspring growth or immune capacity. Unpredictable environmental stressors may thus affect parental investment in the eggs, but parental care may level off costs and benefits of differential maternal egg allocation.
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Affiliation(s)
- Chiara Morosinotto
- Novia University of Applied Sciences, Bioeconomy Research Team, Raseborgsvägen 9, Ekenäs, 10600, Finland .,Department of Biology, Section of Ecology, University of Turku, Turku 20014, Finland
| | - Robert L Thomson
- Department of Biology, Section of Ecology, University of Turku, Turku 20014, Finland.,FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch 7701, South Africa
| | - Erkki Korpimäki
- Department of Biology, Section of Ecology, University of Turku, Turku 20014, Finland
| | - Rafael Mateo
- Instituto de Investigación en Recursos Cinegéticos (IREC), CSIC-UCLM-JCCM, 13005 Ciudad Real, Spain
| | - Suvi Ruuskanen
- Department of Biology, Section of Ecology, University of Turku, Turku 20014, Finland
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41
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Woodruff SP, Jimenez MD. Winter predation patterns of wolves in Northwestern Wyoming. J Wildl Manage 2019. [DOI: 10.1002/jwmg.21710] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Oates BA, Merkle JA, Kauffman MJ, Dewey SR, Jimenez MD, Vartanian JM, Becker SA, Goheen JR. Antipredator response diminishes during periods of resource deficit for a large herbivore. Ecology 2019; 100:e02618. [DOI: 10.1002/ecy.2618] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 10/04/2018] [Accepted: 12/03/2018] [Indexed: 11/10/2022]
Affiliation(s)
- B. A. Oates
- Idaho Department of Fish and Game Boise Idaho 83712 USA
- Wyoming Cooperative Fish and Wildlife Research Unit Department of Zoology and Physiology University of Wyoming Laramie Wyoming 82071 USA
| | - J. A. Merkle
- Wyoming Cooperative Fish and Wildlife Research Unit Department of Zoology and Physiology University of Wyoming Laramie Wyoming 82071 USA
| | - M. J. Kauffman
- U.S. Geological Survey Wyoming Cooperative Fish and Wildlife Research Unit Department of Zoology and Physiology University of Wyoming Laramie Wyoming 82071 USA
| | - S. R. Dewey
- National Park Service Grand Teton National Park Moose Wyoming 83012 USA
| | - M. D. Jimenez
- U.S. Fish and Wildlife Service (retired) Jackson Wyoming 83001 USA
| | | | - S. A. Becker
- U.S. Fish and Wildlife Service Lander Wyoming 82520 USA
| | - J. R. Goheen
- Department of Zoology and Physiology University of Wyoming Laramie Wyoming 82071 USA
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Bhattacharyya S, Dawson DA, Hipperson H, Ishtiaq F. A diet rich in C 3 plants reveals the sensitivity of an alpine mammal to climate change. Mol Ecol 2019; 28:250-265. [PMID: 30136323 PMCID: PMC6391869 DOI: 10.1111/mec.14842] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 07/17/2018] [Accepted: 08/03/2018] [Indexed: 02/06/2023]
Abstract
Plant-herbivore interactions provide critical insights into the mechanisms that govern the spatiotemporal distributions of organisms. These interactions are crucial to understanding the impacts of climate change, which are likely to have an effect on the population dynamics of alpine herbivores. The Royle's pika (Ochotona roylei, hereafter pika) is a lagomorph found in the western Himalaya and is dependent on alpine plants that are at risk from climate change. As the main prey of many carnivores in the region, the pika plays a crucial role in trophic interactions. We examined topographical features, plant genera presence and seasonal dynamics as drivers of the plant richness in the pika's diet across an elevational gradient (2,600-4,450 m). We identified 79 plant genera in the faecal pellets of pikas, of which 89% were forbs, >60% were endemic to the Himalaya, and 97.5% of the diet plant genera identified followed the C3 photosynthetic pathway. We found that, during the premonsoon season, the number of genera in the pika's diet decreased with increasing elevation. We demonstrate that a large area of talus supports greater plant diversity and, not surprisingly, results in higher species richness in the pika's diet. However, in talus habitat with deep crevices, pikas consumed fewer plant genera suggesting they may be foraging suboptimally due to predation risk. The continued increase in global temperature is expected to have an effect on the distribution dynamics of C3 plants and consequently influence pika diet and distribution, resulting in a significant negative cascading effect on the Himalayan ecosystem.
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Affiliation(s)
- Sabuj Bhattacharyya
- Centre for Ecological SciencesIndian Institute of ScienceBangaloreIndia
- Department of Animal and Plant SciencesWestern BankUniversity of SheffieldSheffieldUK
| | - Deborah A. Dawson
- Department of Animal and Plant SciencesWestern BankUniversity of SheffieldSheffieldUK
| | - Helen Hipperson
- Department of Animal and Plant SciencesWestern BankUniversity of SheffieldSheffieldUK
| | - Farah Ishtiaq
- Centre for Ecological SciencesIndian Institute of ScienceBangaloreIndia
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Morosinotto C, Rainio M, Ruuskanen S, Korpimäki E. Antioxidant Enzyme Activities Vary with Predation Risk and Environmental Conditions in Free-Living Passerine Birds. Physiol Biochem Zool 2018; 91:837-848. [PMID: 29494281 DOI: 10.1086/697087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Prolonged physiological stress response may lead to an excessive production of reactive oxygen species (ROS) and ultimately to oxidative stress and severe fitness costs. We investigated whether natural variation in predation risk, induced by pygmy owls (Glaucidium passerinum), modifies the oxidative status of two free-living food-supplemented passerine bird species-the great tit (Parus major) and the willow tit (Poecile montanus)-in March 2012 and 2013. Predation risk significantly affected antioxidant enzyme activities of willow tits. Antioxidant enzyme activities (principal component factor 2 [PC2] representing glutathione-S-transferase and superoxide dismutase activities) were higher in high predation risk areas in 2013 than in low predation risk areas in the same year. Higher enzyme activities may suggest higher ROS production in birds living under high predation risk. In addition, antioxidant enzyme activities (PC2) were also higher in high predation risk areas in 2013 than in high predation risk areas in the previous year, 2012. This may represent variation in the risk represented by pygmy owls, which is probably inversely related to the natural fluctuations in the densities of their main prey, voles. In willow tits, PC1 (representing catalase, total glutathione, the ratio of reduced to oxidized glutathione, and protein carbonylation) was not affected by perceived predation risk, nor were antioxidant levels or enzyme activities in great tits. Higher enzyme activities observed in willow tits suggest that predator presence can modify the antioxidant status of avian prey, but the response also seem to be influenced by other environmental characteristics, like harsh winter conditions.
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Christianson D, Becker MS, Brennan A, Creel S, Dröge E, M'soka J, Mukula T, Schuette P, Smit D, Watson F. Foraging investment in a long-lived herbivore and vulnerability to coursing and stalking predators. Ecol Evol 2018; 8:10147-10155. [PMID: 30397454 PMCID: PMC6206183 DOI: 10.1002/ece3.4489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/12/2018] [Accepted: 08/03/2018] [Indexed: 11/09/2022] Open
Abstract
Allocating resources to growth and reproduction requires grazers to invest time in foraging, but foraging promotes dental senescence and constrains expression of proactive antipredator behaviors such as vigilance. We explored the relationship between carnivore prey selection and prey foraging effort using incisors collected from the kills of coursing and stalking carnivores. We predicted that prey investing less effort in foraging would be killed more frequently by coursers, predators that often exploit physical deficiencies. However, such prey could expect delayed dental senescence. We predicted that individuals investing more effort in foraging would be killed more frequently by stalkers, predators that often exploit behavioral vulnerabilities. Further these prey could expect earlier dental senescence. We tested these predictions by comparing variation in age-corrected tooth wear, a proxy of cumulative foraging effort, in adult (3.4-11.9 years) wildebeest killed by coursing and stalking carnivores. Predator type was a strong predictor of age-corrected tooth wear within each gender. We found greater foraging effort and earlier expected dental senescence, equivalent to 2.6 additional years of foraging, in female wildebeest killed by stalkers than in females killed by coursers. However, male wildebeest showed the opposite pattern with the equivalent of 2.4 years of additional tooth wear in males killed by coursers as compared to those killed by stalkers. Sex-specific variation in the effects of foraging effort on vulnerability was unexpected and suggests that behavioral and physical aspects of vulnerability may not be subject to the same selective pressures across genders in multipredator landscapes.
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Affiliation(s)
- David Christianson
- School of Natural Resources and the EnvironmentUniversity of ArizonaTucsonArizona
| | | | | | - Scott Creel
- Department of EcologyMontana State UniversityBozemanMontana
| | - Egil Dröge
- 5Wildlife Conservation Research UnitDepartment of Zoology, The Recanati‐Kaplan CentreUniversity of Oxford The Recanati‐Kaplan Centre
| | - Jassiel M'soka
- Department of National Parks and WildlifeChilangaLusaka ProvinceZambia
| | - Teddy Mukula
- Zambian Carnivore ProgrammeMfuweEastern ProvinceZambia
| | - Paul Schuette
- Alaska Center for Conservation ScienceAnchorageAlaska
| | - Daan Smit
- Zambian Carnivore ProgrammeMfuweEastern ProvinceZambia
| | - Fred Watson
- School of Natural SciencesCalifornia State University‐Monterey BaySeasideCalifornia
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46
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Predation shapes the evolutionary traits of cervid weapons. Nat Ecol Evol 2018; 2:1619-1625. [DOI: 10.1038/s41559-018-0657-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 07/31/2018] [Indexed: 11/08/2022]
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47
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Creel S. The control of risk hypothesis: reactive vs. proactive antipredator responses and stress-mediated vs. food-mediated costs of response. Ecol Lett 2018; 21:947-956. [PMID: 29744982 DOI: 10.1111/ele.12975] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 03/26/2018] [Accepted: 04/03/2018] [Indexed: 11/26/2022]
Abstract
Inducible defences against predators evolve because they reduce the rate of direct predation, but this benefit is offset by the cost (if any) of defence. If antipredator responses carry costs, the effect of predators on their prey is partitioned into two components, direct killing and risk effects. There is considerable uncertainty about the strength of risk effects, the factors that affect their strength, and the mechanisms that underlie them. In some cases, antipredator responses are associated with a glucocorticoid stress response, and in other cases they are associated with trade-offs between food and safety, but there is no general theory to explain this variation. Here, I develop the control of risk (COR) hypothesis, predicting that proactive responses to predictable and controllable aspects of risk will generally have food-mediated costs, while reactive responses to unpredictable or uncontrollable aspects of predation risk will generally have stress-mediated costs. The hypothesis is grounded in laboratory studies of neuroendocrine stressors and field studies of food-safety trade-offs. Strong tests of the COR hypothesis will require more studies of responses to natural variation in predation risk and the physiological consequences of these responses, but its explanatory power can be illustrated with existing case studies.
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Affiliation(s)
- Scott Creel
- Department of Ecology, Montana State University, 310 Lewis Hall, Bozeman, MT, 59717, USA
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Hebblewhite M, Eacker DR, Eggeman S, Bohm H, Merrill EH. Density-independent predation affects migrants and residents equally in a declining partially migratory elk population. OIKOS 2018. [DOI: 10.1111/oik.05304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mark Hebblewhite
- Wildlife Biology Program, Dept of Ecosystem and Conservation Sciences; W. A. Franke College of Forestry and Conservation, Univ. of Montana; 32 Campus Drive Missoula MT 59812 USA
| | - Daniel R. Eacker
- Wildlife Biology Program, Dept of Ecosystem and Conservation Sciences; W. A. Franke College of Forestry and Conservation, Univ. of Montana; 32 Campus Drive Missoula MT 59812 USA
| | - Scott Eggeman
- Wildlife Biology Program, Dept of Ecosystem and Conservation Sciences; W. A. Franke College of Forestry and Conservation, Univ. of Montana; 32 Campus Drive Missoula MT 59812 USA
| | - Holger Bohm
- Dept of Biological Sciences; Univ. of Alberta; Edmonton AB Canada
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Boada J, Farina S, Arthur R, Romero J, Prado P, Alcoverro T. Herbivore control in connected seascapes: habitat determines when population regulation occurs in the life history of a key herbivore. OIKOS 2018. [DOI: 10.1111/oik.05060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jordi Boada
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC); Carrer d'Accés a la cala Sant Francesc 14 ES-17300 Blanes Spain
| | - Simone Farina
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC); Carrer d'Accés a la cala Sant Francesc 14 ES-17300 Blanes Spain
- Fondazione IMC, Centro Marino Internatzionale Onlus; Torre Grande Oristano Italy
| | - Rohan Arthur
- Nature Conservation Foundation; Mysore Karnataka India
| | - Javier Romero
- Dept d'Ecologia, Facultad de Biologia; Univ. de Barcelona; Barcelona Spain
| | - Patricia Prado
- IRTA, Aquatic Ecosystems; Sant Carles de la Rapita Tarragona Spain
| | - Teresa Alcoverro
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC); Carrer d'Accés a la cala Sant Francesc 14 ES-17300 Blanes Spain
- Nature Conservation Foundation; Mysore Karnataka India
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50
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Hammerschlag N, Meÿer M, Seakamela SM, Kirkman S, Fallows C, Creel S. Physiological stress responses to natural variation in predation risk: evidence from white sharks and seals. Ecology 2017; 98:3199-3210. [DOI: 10.1002/ecy.2049] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 10/06/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Neil Hammerschlag
- Department of Marine Ecosystems and Society; Rosenstiel School of Marine and Atmospheric Sciences; University of Miami; Miami Florida 33149 USA
- Leonard and Jayne Abess Center for Ecosystem Science and Policy; University of Miami; Coral Gables Florida 33146 USA
| | - Michael Meÿer
- Branch: Oceans and Coasts; Department of Environmental Affairs; Private Bag X4390 Cape Town 8000 South Africa
| | - Simon Mduduzi Seakamela
- Branch: Oceans and Coasts; Department of Environmental Affairs; Private Bag X4390 Cape Town 8000 South Africa
| | - Steve Kirkman
- Branch: Oceans and Coasts; Department of Environmental Affairs; Private Bag X4390 Cape Town 8000 South Africa
| | - Chris Fallows
- Apex Shark Expeditions; Shop 3 Quayside Center Simonstown Cape Town 7975 South Africa
| | - Scott Creel
- Department of Ecology; Montana State University; Bozeman Montana 59717 USA
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