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Webber QMR, Laforge MP, Bonar M, Vander Wal E. The adaptive value of density-dependent habitat specialization and social network centrality. Nat Commun 2024; 15:4423. [PMID: 38789438 PMCID: PMC11126670 DOI: 10.1038/s41467-024-48657-8] [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: 01/05/2023] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
Density dependence is a fundamental ecological process. In particular, animal habitat selection and social behavior often affect fitness in a density-dependent manner. The Ideal Free Distribution (IFD) and niche variation hypothesis (NVH) present distinct predictions associated with Optimal Foraging Theory about how the effect of habitat selection on fitness varies with population density. Using caribou (Rangifer tarandus) in Canada as a model system, we test competing hypotheses about how habitat specialization, social behavior, and annual reproductive success (co)vary across a population density gradient. Within a behavioral reaction norm framework, we estimate repeatability, behavioral plasticity, and covariance among social behavior and habitat selection to investigate the adaptive value of sociality and habitat selection. In support of NVH, but not the IFD, we find that at high density habitat specialists had higher annual reproductive success than generalists, but were also less social than generalists, suggesting the possibility that specialists were less social to avoid competition. Our study supports niche variation as a mechanism for density-dependent habitat specialization.
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Affiliation(s)
- Quinn M R Webber
- Cognitive and Behavioural Ecology Interdisciplinary Program, Memorial University of Newfoundland, St. John's, NF, Canada.
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada.
| | - Michel P Laforge
- Department of Biology, Memorial University of Newfoundland, St. John's, NF, Canada
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA
| | - Maegwin Bonar
- Department of Biology, Memorial University of Newfoundland, St. John's, NF, Canada
- Department of Ecology & Evolutionary Biology, Yale University, New Haven, CT, USA
| | - Eric Vander Wal
- Cognitive and Behavioural Ecology Interdisciplinary Program, Memorial University of Newfoundland, St. John's, NF, Canada
- Department of Biology, Memorial University of Newfoundland, St. John's, NF, Canada
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Monfils MH, Pasala M, Malone C, Agee L, Roquet R, Cormack L. Effects of group size on movement patterns and clustering dynamics in rats. OXFORD OPEN NEUROSCIENCE 2024; 3:kvae005. [PMID: 38628432 PMCID: PMC11019387 DOI: 10.1093/oons/kvae005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 02/26/2024] [Accepted: 03/07/2024] [Indexed: 04/19/2024]
Abstract
Environment is a determining factor that can facilitate or hinder social interactions. A precursor to meaningfully engaging with conspecifics is being exposed to opportunistic encounters with others. Increasing the number of individuals in a given space (thus increasing density) would, statistically speaking, increase the likelihood of accidental encounters. This might have consequences on the formation of social networks-an idea that has not reliably been explored. If true, we would expect that increasing density would lead to an increase in the number and the duration of 'clusters' of animals. Here, we examined whether varying the number of rats in an open field environment differentially affected their movement dynamics or their propensity to aggregate into clusters and, if so, whether such effects are dependent solely on statistical factors due to increases in density, the potential for actively-sought social interactions, or both. We found that the number of rats in an environment impacts ambulation speed, distance traveled, cluster formation and approaches, and that number and duration of clusters are highly dependent on the propensity for the rats to engage in social interactions.
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Affiliation(s)
- Marie-H Monfils
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton Stop A8000, Austin, TX 78712-1043, USA
| | - Michael Pasala
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton Stop A8000, Austin, TX 78712-1043, USA
| | - Cassidy Malone
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton Stop A8000, Austin, TX 78712-1043, USA
| | - Laura Agee
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton Stop A8000, Austin, TX 78712-1043, USA
| | - Rheall Roquet
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton Stop A8000, Austin, TX 78712-1043, USA
| | - Lawrence Cormack
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton Stop A8000, Austin, TX 78712-1043, USA
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Monnier-Corbel A, Robert A, Hingrat Y, Benito BM, Monnet AC. Species Distribution Models predict abundance and its temporal variation in a steppe bird population. Glob Ecol Conserv 2023. [DOI: 10.1016/j.gecco.2023.e02442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023] Open
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4
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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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5
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Šigutová H, Šigut M, Dolný A, Harabiš F. Individual variability in habitat selection by aquatic insects is driven by taxonomy rather than specialisation. Sci Rep 2022; 12:20735. [PMID: 36456650 PMCID: PMC9715563 DOI: 10.1038/s41598-022-25363-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 11/29/2022] [Indexed: 12/05/2022] Open
Abstract
Habitat selection, the choice of a habitat based on its perceived quality, is a key mechanism structuring freshwater communities. To date, individual variability in habitat selection has been neglected, and specialisation has never been considered in this type of studies. We examined the individual differences in the habitat selection of backswimmers (Notonectidae) and diving beetles (Dytiscidae). From each family, we selected one habitat generalist able to coexist with fish (Notonecta glauca, Dytiscus marginalis), and one species specialised to fishless habitats (Notonecta obliqua, Acilius sulcatus). We performed a mesocosm experiment quantifying the consistency in individuals' decisions in response to fish and vegetation structure, in relation to sex and specialisation. Neither the overall pattern of preferences nor consistency in individuals' decisions differed between specialists and generalists or between the sexes, but both were consistent within families. At the population level, backswimmers preferred fishless pools with submersed and floating macrophytes, while diving beetles showed no clear preferences. Individual decisions of backswimmers were consistent and likely driven by conspecific/heterospecific attraction. In diving beetles, individual decisions were primarily density-dependent. Our results reinforce the significance of habitat selectivity for aquatic community assembly, while suggesting a range of mechanisms driving variability in individual behaviour.
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Affiliation(s)
- Hana Šigutová
- grid.412684.d0000 0001 2155 4545Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic ,grid.10979.360000 0001 1245 3953Department of Zoology, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Martin Šigut
- grid.412684.d0000 0001 2155 4545Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Aleš Dolný
- grid.412684.d0000 0001 2155 4545Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Filip Harabiš
- grid.15866.3c0000 0001 2238 631XDepartment of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Prague, Czech Republic
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6
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Aliperti JR, Jenderseck K, Van Vuren DH. Habitat selection in a fluctuating ground squirrel population: Density‐dependence and fitness consequences. Ecol Evol 2022; 12:e9241. [PMID: 36052297 PMCID: PMC9424181 DOI: 10.1002/ece3.9241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 07/29/2022] [Accepted: 08/01/2022] [Indexed: 11/10/2022] Open
Abstract
Investigating individual‐based habitat settlement decisions is a central theme in ecology, yet studies that quantify density‐dependent habitat selection or tie fitness to resource selection decisions remain rare. We quantified habitat selection in golden‐mantled ground squirrels (Callospermophilus lateralis) across two spatial scales (home‐range placement, and occurrence within the home range) by using 11 consecutive years of data on individual space use, and we used resource selection functions and multilevel modeling to address how habitat preferences may be influenced by density or linked to fitness outcomes. Squirrels preferred dry meadow over other habitat types (wet meadow, aspen, spruce, and willow) at both spatial scales. Squirrels were more likely to use dry meadow that contained shorter vegetation and vision‐enhancing prominences such as rocks (“perches”). The use of dry meadow at each scale was not influenced by changes in density. The use of dry meadow did not lead to increased litter size, pre‐hibernation mass, or survival. However, squirrels that experienced a greater number of perches or lower local densities had higher survival rates. Our results suggest that a lack of visual obstruction, probably facilitating detection of predators, drives habitat selection in this system. Surprisingly, squirrels maintained their preference for dry meadow as density increased, and they experienced reduced survival as a result. This work furthers our understanding about the causes and consequences of changes in habitat use, informing wildlife management and conservation.
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Affiliation(s)
- Jaclyn R. Aliperti
- Department of Wildlife, Fish, and Conservation Biology University of California Davis CA USA
- Rocky Mountain Biological Laboratory Crested Butte CO USA
| | - Kimberly Jenderseck
- Department of Wildlife, Fish, and Conservation Biology University of California Davis CA USA
- Rocky Mountain Biological Laboratory Crested Butte CO USA
| | - Dirk H. Van Vuren
- Department of Wildlife, Fish, and Conservation Biology University of California Davis CA USA
- Rocky Mountain Biological Laboratory Crested Butte CO USA
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Becker JA, Hutchinson MC, Potter AB, Park S, Guyton JA, Abernathy K, Americo VF, Conceiçāo A, Kartzinel TR, Kuziel L, Leonard NE, Lorenzi E, Martins NC, Pansu J, Scott WL, Stahl MK, Torrens KR, Stalmans ME, Long RA, Pringle RM. Ecological and behavioral mechanisms of density‐dependent habitat expansion in a recovering African ungulate population. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1476] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Justine A. Becker
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
- Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming, 82072, USA
| | - Matthew C. Hutchinson
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
| | - Arjun B. Potter
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
| | - Shinkyu Park
- Department of Mechanical and Aerospace Engineering Princeton University Princeton New Jersey 08544 USA
| | - Jennifer A. Guyton
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
| | - Kyler Abernathy
- Exploration Technology Lab National Geographic Society Washington D.C. 20036 USA
| | - Victor F. Americo
- Department of Scientific Services Parque Nacional da Gorongosa Sofala Mozambique
| | - Anagledis Conceiçāo
- Department of Scientific Services Parque Nacional da Gorongosa Sofala Mozambique
| | - Tyler R. Kartzinel
- Department of Ecology and Evolutionary Biology Brown University Providence Rhode Island 02912 USA
- Institute at Brown for Environment and Society Brown University Providence Rhode Island 02912 USA
| | - Luca Kuziel
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
| | - Naomi E. Leonard
- Department of Mechanical and Aerospace Engineering Princeton University Princeton New Jersey 08544 USA
| | - Eli Lorenzi
- Department of Electrical and Computer Engineering University of Maryland College Park Maryland 20742 USA
| | - Nuno C. Martins
- Department of Electrical and Computer Engineering University of Maryland College Park Maryland 20742 USA
| | - Johan Pansu
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
- Station Biologique de Roscoff UMR 7144 CNRS‐Sorbonne Université Roscoff France
- CSIRO Ocean & Atmosphere Lucas Heights New South Wales Australia
| | - William L. Scott
- Department of Mechanical Engineering Bucknell University Lewisburg Pennsylvania 17837 USA
| | - Maria K. Stahl
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
| | - Kai R. Torrens
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
| | - Marc E. Stalmans
- Department of Scientific Services Parque Nacional da Gorongosa Sofala Mozambique
| | - Ryan A. Long
- Department of Fish and Wildlife Sciences University of Idaho Moscow Idaho 83844 USA
| | - Robert M. Pringle
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey 08544 USA
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Larson RT, Bron GM, Lee X, Paskewitz SM. High Proportion of Unfed Larval Blacklegged Ticks, Ixodes scapularis (Acari: Ixodidae), Collected From Modified Nest Boxes for Mice. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:1448-1453. [PMID: 33471096 DOI: 10.1093/jme/tjaa287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Indexed: 06/12/2023]
Abstract
The blacklegged tick, Ixodes scapularis Say, is the primary vector of several tick-borne pathogens, including those causing Lyme disease and babesiosis, in the eastern United States and active collection methods for this species include dragging or wild animal sampling. Nest boxes targeting mice may be an alternative strategy for the surveillance and collection of immature I. scapularis feeding on these hosts and would be much safer for animals compared to small mammal trapping. We constructed double-walled insulated nest boxes (DWINs) with collection tubes mounted below the nesting chamber and deployed eleven in southern Wisconsin from June until September of 2020. The DWINs were occupied by Peromyscus spp. and birds (wren species, Troglodytidae family). We collected 192 ticks from collection tubes, all of which were identified as either I. scapularis (95%) or Dermacentor variabilis Say (Acari: Ixodidae) (5%). Only 12% (21/182) and 20% (2/10) of I. scapularis and D. variabilis were blood-fed, respectively. The high proportion of unfed ticks found in collection tubes may be due to grooming by hosts inside the nest boxes. Alternatively, immature ticks may have climbed trees and entered the DWIN seeking a host. Results suggest that nest boxes could be a tool for finding ticks in areas of low density or at the leading edge of invasion, when small mammal trapping or drag sampling is not feasible.
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Affiliation(s)
- R T Larson
- College of Agricultural and Life Sciences, Department of Entomology, University of Wisconsin - Madison, Madison, WI
- Lieutenant Commander, Medical Service Corps, U.S. Navy
- Naval Medical Leader & Professional Development Command (NML & PDC), 8955 Wood Road, Bethesda, MD
| | - G M Bron
- College of Agricultural and Life Sciences, Department of Entomology, University of Wisconsin - Madison, Madison, WI
| | - X Lee
- College of Agricultural and Life Sciences, Department of Entomology, University of Wisconsin - Madison, Madison, WI
| | - S M Paskewitz
- College of Agricultural and Life Sciences, Department of Entomology, University of Wisconsin - Madison, Madison, WI
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Centeno-Cuadros A, Román J, Sánchez-Recuero A, Lucena-Pérez M, Delibes M, Godoy JA. Mating System, Breeding Success, and Pup Mortality of a Habitat Specialist Rodent: A Field and Molecular-based Approach. J MAMM EVOL 2021. [DOI: 10.1007/s10914-021-09542-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Northrup JM, Anderson CR, Gerber BD, Wittemyer G. Behavioral and Demographic Responses of Mule Deer to Energy Development on Winter Range. WILDLIFE MONOGRAPHS 2021. [DOI: 10.1002/wmon.1060] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Joseph M. Northrup
- Department of Fish, Wildlife and Conservation Biology Colorado State University 1474 Campus Delivery Fort Collins CO 80523 USA
- ; and Wildlife Research and Monitoring Section Ontario Ministry of Natural Resources and Forestry 2140 East Bank Drive Peterborough ON K9L 1Z8 Canada
| | - Charles R. Anderson
- Mammals Research Section Colorado Parks and Wildlife 317 W Prospect Road Fort Collins CO 80526 USA
| | - Brian D. Gerber
- Department of Natural Resources Science University of Rhode Island 1 Greenhouse Road Kingston RI 02881‐2018 USA
| | - George Wittemyer
- Department of Fish, Wildlife and Conservation Biology Colorado State University 1474 Campus Delivery Fort Collins CO 80523 USA
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11
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The resilient frugivorous fauna of an urban forest fragment and its potential role in vegetation enrichment. Urban Ecosyst 2021; 24:943-958. [PMID: 33432262 PMCID: PMC7787706 DOI: 10.1007/s11252-020-01080-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2020] [Indexed: 11/04/2022]
Abstract
Anthropocentric defaunation affects critical ecological processes, such as seed dispersal, putting ecosystems and biomes at risk, and leading to habitat impoverishment. Diverse restoration techniques could reverse the process of habitat impoverishment. However, in most of the restoration efforts, only vegetation cover is targeted. Fauna and flora are treated as isolated components, neglecting a key component of ecosystems’ functioning, the ecological interactions. We tested whether the resilient frugivorous generalist fauna can improve habitat quality by dispersing native plant species through the use of fruit feeders as in a semideciduous seasonal urban forest fragment. A total of 32 sampling points was selected at a heavily degraded 251-ha urban forest fragment, with feeders installed at two heights monitored by camera-traps. Variable quantities of native fruits of 27 zoochorous species were offered alternately in the feeders. Based on more than 36,000 h of video records, Turdus leucomelas (Class Aves), Sapajus nigritus (Class Mammalia), and Salvator merianae (Class Reptilia) were recorded ingesting the highest fruit species richness. Didelphis albiventris (Class Mammalia) was the most frequent visitor but consumed only pulp in most of the visits. The frugivorous birds were recorded at a high visitation rate and consumed a wider variety of fruits. Our study opens a new avenue to combine the traditional approach of ecosystems recovery and ecological interactions restauration in an urban forest fragment.
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Harmange C, Bretagnolle V, Sarasa M, Pays O. Changes in habitat selection patterns of the gray partridge Perdix perdix in relation to agricultural landscape dynamics over the past two decades. Ecol Evol 2019; 9:5236-5247. [PMID: 31110675 PMCID: PMC6509401 DOI: 10.1002/ece3.5114] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 03/04/2019] [Accepted: 03/08/2019] [Indexed: 12/25/2022] Open
Abstract
Changes in agricultural practices have reshaped agricultural landscapes and triggered a drastic decline in spatial and temporal heterogeneity leading to changes in habitat quality and food resources for birds. However, the precise relationships between landscape changes, spatial and temporal heterogeneity, and habitat preferences in response to those changes remain poorly known.We investigated patterns of habitat selection and causes for changes over the years 1997-2017 for the gray partridge Perdix perdix, an iconic farmland species which has experienced a severe decline since the 1950s. Using a long-term (1997-2017) dataset collected over 435 km2, we modeled relationships between annual land-cover maps and partridge sightings over 17 5-year moving windows, assessing the effects of landscape metrics, the strength of the relationships, and the dynamics of habitat suitability.We detected a shift in gray partridge habitat preferences over time, toward more risky habitats. Avoidance of predator reservoirs (woodlands and buildings) has weakened, and selection of human infrastructure, such as roads and tracks, has increased. Since 1997, the mean size of suitable patches has also decreased by about 26%.We have interpreted these changes in habitat selection as being the result of decreasing habitat quality and the increasing prevalence of captive-reared birds, currently released in their thousands in the study site. Synthesis and applications. The gray partridge has not adjusted well to changes in farming practices, and the low, still decreasing, population density suggests that it is not sustainable, despite local initiatives and the investment in captive-bird releases. We emphasize that efforts must be redirected toward habitat improvement to restore the density of refuge cover, insects, and seeds in the landscape, hunting management to ensure self-sustainable populations and massive releases of high-quality birds. Only integrated local management, involving hunters, farmers, gamekeepers, and scientists can ensure the recovery of this species.
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Affiliation(s)
- Clément Harmange
- CNRS, UMR LETG, UFR SciencesUniversité d'AngersAngers Cedex 01France
- Centre d'Etudes Biologiques de Chizé, UMR 7372, CNRSUniversité La RochelleBeauvoir‐sur‐NiortFrance
| | - Vincent Bretagnolle
- Centre d'Etudes Biologiques de Chizé, UMR 7372, CNRSUniversité La RochelleBeauvoir‐sur‐NiortFrance
- LTSER “Zone Atelier Plaine & Val de Sèvre”CNRSBeauvoir sur NiortFrance
| | - Mathieu Sarasa
- BEOPSToulouseFrance
- Fédération Nationale des ChasseursIssy‐les‐Moulineaux cedexFrance
| | - Olivier Pays
- CNRS, UMR LETG, UFR SciencesUniversité d'AngersAngers Cedex 01France
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Fokkema RW, Ubels R, Both C, de Felici L, Tinbergen JM. Reproductive effort and future parental competitive ability: A nest box removal experiment. Ecol Evol 2018; 8:8865-8879. [PMID: 30271551 PMCID: PMC6157679 DOI: 10.1002/ece3.4342] [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: 01/08/2018] [Revised: 06/05/2018] [Accepted: 06/13/2018] [Indexed: 11/08/2022] Open
Abstract
The life history trade-off between current and future reproduction is a theoretically well-established concept. However, empirical evidence for the occurrence of a fitness cost of reproduction is mixed. Evidence indicates that parents only pay a cost of reproduction when local competition is high. In line with this, recent experimental work on a small passerine bird, the Great tit (Parus major) showed that reproductive effort negatively affected the competitive ability of parents, estimated through competition for high quality breeding sites in spring. In the current study, we further investigate the negative causal relationship between reproductive effort and future parental competitive ability, with the aim to quantify the consequences for parental fitness, when breeding sites are scarce. To this end, we (a) manipulated the family size of Great tit parents and (b) induced severe competition for nest boxes among the parents just before the following breeding season by means of a large-scale nest box removal experiment. Parents increased their feeding effort in response to our family size manipulation and we successfully induced competition among the parents the following spring. Against our expectation, we found no effect of last season's family size on the ability of parents to secure a scarce nest box for breeding. In previous years, if detected, the survival cost of reproduction was always paid after midwinter. In this year, parents did pay a survival cost of reproduction before midwinter and thus before the onset of the experiment in early spring. Winter food availability during our study year was exceptionally low, and thus, competition in early winter may have been extraordinarily high. We hypothesize that differences in parental competitive ability due to their previous reproductive effort might have played a role, but before the onset of our experiment and resulted in the payment of the survival cost of reproduction.
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Affiliation(s)
- Rienk W. Fokkema
- Conservation Ecology GroupGroningen Institute for Evolutionary Life Sciences (GELIFES)University of GroningenGroningenThe Netherlands
- Evolutionary BiologyBielefeld UniversityBielefeldGermany
- Department of Animal BehaviourBielefeld UniversityBielefeldGermany
| | - Richard Ubels
- Conservation Ecology GroupGroningen Institute for Evolutionary Life Sciences (GELIFES)University of GroningenGroningenThe Netherlands
| | - Christiaan Both
- Conservation Ecology GroupGroningen Institute for Evolutionary Life Sciences (GELIFES)University of GroningenGroningenThe Netherlands
| | - Livia de Felici
- Conservation Ecology GroupGroningen Institute for Evolutionary Life Sciences (GELIFES)University of GroningenGroningenThe Netherlands
| | - Joost M. Tinbergen
- Conservation Ecology GroupGroningen Institute for Evolutionary Life Sciences (GELIFES)University of GroningenGroningenThe Netherlands
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Paterson JE, Blouin-Demers G. Tree lizard (Urosaurus ornatus) growth decreases with population density, but increases with habitat quality. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 329:527-535. [PMID: 30096219 DOI: 10.1002/jez.2216] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 07/03/2018] [Accepted: 07/05/2018] [Indexed: 11/08/2022]
Abstract
Habitat selection models can explain spatial patterns in the relative abundance of animals in different habitats based on the assumption that fitness declines as density in a habitat increases. Ectotherms, such as lizards, may not follow predictions of density-dependent habitat selection models because temperature, which is unaffected by density, strongly influences their habitat selection. If competition for limited resources decreases fitness, then crowding should cause a decrease in body size and growth rates. We used skeletochronology and body size data from tree lizards (Urosaurus ornatus) at six sites that each spanned two habitats varying in quality to test the hypothesis that habitat selection is density dependent because growth is limited by competition for resources and by habitat quality. First, we tested that the maximum body size of lizards decreased with higher densities in a habitat by comparing growth between sites. Second, we tested whether body size and growth were higher in the habitat with more resources by controlling for density in a habitat and comparing growth between habitats in different sites. We found evidence of density-dependent growth in females, but not in males. Females in more crowded sites reached a smaller maximum size. Females in the higher quality habitat also grew larger than females in the lower quality habitat after controlling for differences in density between the habitats. Therefore, we found partial support for our hypothesis that competition for resources limits growth and causes density-dependent habitat selection.
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Affiliation(s)
- James E Paterson
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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15
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Adar S, Dor R. Mother doesn't always know best: Maternal wormlion choice of oviposition habitat does not match larval habitat choice. Behav Processes 2018; 147:1-4. [DOI: 10.1016/j.beproc.2017.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 11/16/2017] [Accepted: 12/04/2017] [Indexed: 11/30/2022]
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16
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Sample C, Fryxell JM, Bieri JA, Federico P, Earl JE, Wiederholt R, Mattsson BJ, Flockhart DTT, Nicol S, Diffendorfer JE, Thogmartin WE, Erickson RA, Norris DR. A general modeling framework for describing spatially structured population dynamics. Ecol Evol 2017; 8:493-508. [PMID: 29321888 PMCID: PMC5756893 DOI: 10.1002/ece3.3685] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 09/27/2017] [Accepted: 11/08/2017] [Indexed: 11/06/2022] Open
Abstract
Variation in movement across time and space fundamentally shapes the abundance and distribution of populations. Although a variety of approaches model structured population dynamics, they are limited to specific types of spatially structured populations and lack a unifying framework. Here, we propose a unified network-based framework sufficiently novel in its flexibility to capture a wide variety of spatiotemporal processes including metapopulations and a range of migratory patterns. It can accommodate different kinds of age structures, forms of population growth, dispersal, nomadism and migration, and alternative life-history strategies. Our objective was to link three general elements common to all spatially structured populations (space, time and movement) under a single mathematical framework. To do this, we adopt a network modeling approach. The spatial structure of a population is represented by a weighted and directed network. Each node and each edge has a set of attributes which vary through time. The dynamics of our network-based population is modeled with discrete time steps. Using both theoretical and real-world examples, we show how common elements recur across species with disparate movement strategies and how they can be combined under a unified mathematical framework. We illustrate how metapopulations, various migratory patterns, and nomadism can be represented with this modeling approach. We also apply our network-based framework to four organisms spanning a wide range of life histories, movement patterns, and carrying capacities. General computer code to implement our framework is provided, which can be applied to almost any spatially structured population. This framework contributes to our theoretical understanding of population dynamics and has practical management applications, including understanding the impact of perturbations on population size, distribution, and movement patterns. By working within a common framework, there is less chance that comparative analyses are colored by model details rather than general principles.
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Affiliation(s)
| | - John M Fryxell
- Department of Integrative Biology University of Guelph Guelph ON Canada
| | - Joanna A Bieri
- Department of Mathematics University of Redlands Redlands CA USA
| | - Paula Federico
- Department of Mathematics, Computer Science and Physics Capital University Columbus OH USA
| | - Julia E Earl
- School of Biological Sciences Louisiana Tech University Ruston LA USA
| | | | - Brady J Mattsson
- Institute of Silviculture University of Natural Resources and Life Sciences Vienna Austria.,Present address: Institute of Wildlife Biology & Game Management University of Natural Resources & Life Sciences (BOKU) Vienna Austria
| | | | - Sam Nicol
- CSIRO Land and Water, EcoSciences Precinct Dutton Park Qld Australia
| | - Jay E Diffendorfer
- U.S. Geological Survey, Geosciences and Environmental Change Science Center Denver CO USA
| | - Wayne E Thogmartin
- U.S. Geological Survey Upper Midwest Environmental Sciences Center La Crosse WI USA
| | - Richard A Erickson
- U.S. Geological Survey Upper Midwest Environmental Sciences Center La Crosse WI USA
| | - D Ryan Norris
- Department of Integrative Biology University of Guelph Guelph ON Canada
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17
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Paterson JE, Blouin-Demers G. Density-dependent habitat selection predicts fitness and abundance in a small lizard. OIKOS 2017. [DOI: 10.1111/oik.04758] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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18
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O'Neil ST, Bump JK, Beyer DE. Spatially varying density dependence drives a shifting mosaic of survival in a recovering apex predator ( Canis lupus). Ecol Evol 2017; 7:9518-9530. [PMID: 29187986 PMCID: PMC5696399 DOI: 10.1002/ece3.3463] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/24/2017] [Accepted: 08/31/2017] [Indexed: 11/06/2022] Open
Abstract
Understanding landscape patterns in mortality risk is crucial for promoting recovery of threatened and endangered species. Humans affect mortality risk in large carnivores such as wolves (Canis lupus), but spatiotemporally varying density dependence can significantly influence the landscape of survival. This potentially occurs when density varies spatially and risk is unevenly distributed. We quantified spatiotemporal sources of variation in survival rates of gray wolves (C. lupus) during a 21‐year period of population recovery in the Upper Peninsula of Michigan, USA. We focused on mapping risk across time using Cox Proportional Hazards (CPH) models with time‐dependent covariates, thus exploring a shifting mosaic of survival. Extended CPH models and time‐dependent covariates revealed influences of seasonality, density dependence and experience, as well as individual‐level factors and landscape predictors of risk. We used results to predict the shifting landscape of risk at the beginning, middle, and end of the wolf recovery time series. Survival rates varied spatially and declined over time. Long‐term change was density‐dependent, with landscape predictors such as agricultural land cover and edge densities contributing negatively to survival. Survival also varied seasonally and depended on individual experience, sex, and resident versus transient status. The shifting landscape of survival suggested that increasing density contributed to greater potential for human conflict and wolf mortality risk. Long‐term spatial variation in key population vital rates is largely unquantified in many threatened, endangered, and recovering species. Variation in risk may indicate potential for source‐sink population dynamics, especially where individuals preemptively occupy suitable territories, which forces new individuals into riskier habitat types as density increases. We encourage managers to explore relationships between adult survival and localized changes in population density. Density‐dependent risk maps can identify increasing conflict areas or potential habitat sinks which may persist due to high recruitment in adjacent habitats.
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Affiliation(s)
- Shawn T O'Neil
- School of Forest Resources and Environmental Science Michigan Technological University Houghton MI USA.,Present address: U.S. Geological Survey Western Ecological Research Center 800 Business Park Dr. Suite D Dixon CA, 95620
| | - Joseph K Bump
- Department of Fisheries, Wildlife and Conservation Biology University of Minnesota St. Paul MN USA
| | - Dean E Beyer
- School of Forest Resources and Environmental Science Michigan Technological University Houghton MI USA.,Wildlife Division Michigan Department of Natural Resources Marquette MI USA
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19
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Peterson BE, Storm DJ, Norton AS, Van Deelen TR. Landscape influence on dispersal of yearling male white-tailed deer. J Wildl Manage 2017. [DOI: 10.1002/jwmg.21318] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Brittany E. Peterson
- Department of Forest and Wildlife Ecology; University of Wisconsin-Madison; 1630 Linden Drive Madison WI 53706 USA
| | - Daniel J. Storm
- Bureau of Science Services; Wisconsin Department of Natural Resources; 107 Sutliff Avenue Rhinelander WI 54501 USA
| | - Andrew S. Norton
- Wildlife Research; Minnesota Department of Natural Resources; 35365 800th Avenue Madelia MN 56062 USA
| | - Timothy R. Van Deelen
- Department of Forest and Wildlife Ecology; University of Wisconsin-Madison; 1630 Linden Drive Madison WI 53706 USA
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20
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Morris DW. OPTIMUM BROOD SIZE: TESTS OF ALTERNATIVE HYPOTHESES. Evolution 2017; 46:1848-1861. [DOI: 10.1111/j.1558-5646.1992.tb01173.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/1990] [Accepted: 04/15/1992] [Indexed: 11/29/2022]
Affiliation(s)
- Douglas W. Morris
- Centre for Northern Studies; Department of Biology; School of Forestry, Lakehead University; Thunder Bay Ontario P7B 5E1 CANADA
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21
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Fokkema RW, Ubels R, Tinbergen JM. Is parental competitive ability in winter negatively affected by previous springs' family size? Ecol Evol 2017; 7:1410-1420. [PMID: 28261453 PMCID: PMC5330910 DOI: 10.1002/ece3.2752] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 12/19/2016] [Accepted: 12/22/2016] [Indexed: 11/26/2022] Open
Abstract
Reproductive behavior cannot be understood without taking the local level of competition into account. Experimental work in great tits (Parus major) showed that (1) a survival cost of reproduction was paid in environments with high levels of competition during the winter period and (2) experimentally manipulated family size negatively affected the ability of parents to compete for preferred breeding boxes in the next spring. The fact that survival was affected in winter suggests that the competitive ability of parents in winter may also be affected by previous reproductive effort. In this study, we aim to investigate whether (1) such carryover effects of family size on the ability of parents to compete for resources in the winter period occurred and (2) this could explain the occurrence of a survival cost of reproduction under increased competition. During two study years, we manipulated the size of in total 168 great tit broods. Next, in winter, we induced competition among the parents by drastically reducing the availability of roosting boxes in their local environment for one week. Contrary to our expectation, we found no negative effect of family size manipulation on the probability of parents to obtain a roosting box. In line with previous work, we did find that a survival cost of reproduction was paid only in plots in which competition for roosting boxes was shortly increased. Our findings thus add to the scarce experimental evidence that survival cost of reproduction are paid under higher levels of local competition but this could not be linked to a reduced competitive ability of parents in winter.
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Affiliation(s)
- Rienk W Fokkema
- Conservation Ecology Group Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
| | - Richard Ubels
- Conservation Ecology Group Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
| | - Joost M Tinbergen
- Conservation Ecology Group Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
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22
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McGeachy D, Hamr J, Mallory F. Metapopulation dynamics and space use by reintroduced elk (Cervus elaphus) in central Ontario. CAN J ZOOL 2017. [DOI: 10.1139/cjz-2016-0130] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Understanding population structure and resource selection is essential for wildlife management and conservation. We assessed the population structure of elk (Cervus elaphus L.,1758) in central Ontario. We used fuzzy and hierarchical cluster analyses to elucidate elk population structure based on spatial data collected from 41 radio-collared elk. We assessed space use between core and satellite subpopulations with the minimum convex polygon (MCP) and fixed kernel methods. Both fuzzy and hard clustering indicated that elk in this part of central Ontario occur in a metapopulation that includes five subpopulations. The largest cluster consisted of a core group containing 22 radio-collared elk located in Burwash, with several satellite subpopulations spread along a 50 km long north–south axis and a small subpopulation to the west located in Worthington. Survival rates among subpopulations were similar, ranging from 0.71 to 0.83, and anthropogenic causes of mortality were predominant only in the Burwash subpopulation. Space use and density of elk differed between core and satellite subpopulations. Understanding population structure is important to develop appropriate management plans. Our results support the conclusion that metapopulation structure can be reliably assessed using spatial data.
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Affiliation(s)
- D. McGeachy
- Laurentian University, Department of Biology, 935 Ramsey Lake Road, Sudbury, ON P3E 2C6, Canada
| | - J. Hamr
- Cambrian College, School of Renewable Energy and Environmental Studies, 1300 Barrydowne Road, Sudbury, ON P3A 3V8, Canada
| | - F.F. Mallory
- Laurentian University, Department of Biology, 935 Ramsey Lake Road, Sudbury, ON P3E 2C6, Canada
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23
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Adar S, Scharf I, Dor R. The effect of previous experience on trap construction and movement distance in a pit-building predator. Naturwissenschaften 2016; 103:83. [PMID: 27659499 DOI: 10.1007/s00114-016-1405-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 09/04/2016] [Accepted: 09/07/2016] [Indexed: 11/29/2022]
Abstract
Wormlion larvae are sit-and-wait predators that construct cone-shaped pits in sandy patches to capture prey. Wormlions select microhabitats that feature favorable conditions for pit construction, in a similar way to other trap-building predators, like spiders and antlions. We investigated whether wormlions exhibit an experience-based behavioral plasticity in their pit construction behavior. In a laboratory experiment, pit sizes and relocation distances were compared between larvae that experienced either a period of unfavorable conditions, i.e., surface obstacles, shallow or coarse sand, or a period of favorable conditions, i.e., clear, deep, and fine sand and were able to construct pits undisturbed. We expected that wormlions experiencing improving conditions would build larger pits than those experiencing deteriorating conditions. In addition, we expected that larvae experiencing unfavorable conditions would be less choosy in their new microhabitat and move over shorter distances. We observed a certain effect of recent experience on the trap-building behavior; however, it was not consistent among treatments. Additionally, we detected a correlation between larval body mass, relocation distance, and pit area. These findings might suggest that past experience does not influence wormlion foraging behavior in a simple manner but that different types of experience induce different behavioral responses.
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Affiliation(s)
- Shay Adar
- Department of Zoology, Faculty of Life Sciences, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Inon Scharf
- Department of Zoology, Faculty of Life Sciences, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Roi Dor
- Department of Zoology, Faculty of Life Sciences, Tel Aviv University, 69978, Tel Aviv, Israel.
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24
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Antunes PC, Oliveira-Santos LGR, Tomas WM, Forester JD, Fernandez FAS. Disentangling the effects of habitat, food, and intraspecific competition on resource selection by the spiny rat, Thrichomys fosteri. J Mammal 2016. [DOI: 10.1093/jmammal/gyw140] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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25
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Bester-Meredith JK, Burns JN, Conley MF, Mammarella GE, Ng ND. Peromyscus as a model system for understanding the regulation of maternal behavior. Semin Cell Dev Biol 2016; 61:99-106. [PMID: 27381343 DOI: 10.1016/j.semcdb.2016.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 06/30/2016] [Accepted: 07/01/2016] [Indexed: 12/31/2022]
Abstract
The genus Peromyscus has been used as a model system for understanding maternal behavior because of the diversity of reproductive strategies within this genus. This review will describe the ecological factors that determine litter size and litter quality in polygynous species such as Peromyscus leucopus and Peromyscus maniculatus. We will also outline the physiological and social factors regulating maternal care in Peromyscus californicus, a monogamous and biparental species. Because biparental care is relatively rare in mammals, most research in P. californicus has focused on understanding the biology of paternal care while less research has focused on understanding maternal care. As a result, the social, sensory, and hormonal cues used to coordinate parental care between male and female P. californicus have been relatively well-studied. However, less is known about the physiology of maternal care in P. californicus and in other Peromyscus species. The diversity of the genus Peromyscus provides the potential for future research to continue to examine how variation in social systems has shaped the mechanisms that underlie maternal care.
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Affiliation(s)
- Janet K Bester-Meredith
- Seattle Pacific University, Department of Biology, 3307 3rd Ave West, Seattle, WA 98119, USA.
| | - Jennifer N Burns
- Seattle Pacific University, Department of Biology, 3307 3rd Ave West, Seattle, WA 98119, USA
| | - Mariah F Conley
- Seattle Pacific University, Department of Biology, 3307 3rd Ave West, Seattle, WA 98119, USA
| | - Grace E Mammarella
- Seattle Pacific University, Department of Biology, 3307 3rd Ave West, Seattle, WA 98119, USA
| | - Nathaniel D Ng
- Seattle Pacific University, Department of Biology, 3307 3rd Ave West, Seattle, WA 98119, USA
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26
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Fokkema RW, Ubels R, Tinbergen JM. Great tits trade off future competitive advantage for current reproduction. Behav Ecol 2016. [DOI: 10.1093/beheco/arw097] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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27
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Mariani P, Křivan V, MacKenzie BR, Mullon C. The migration game in habitat network: the case of tuna. THEOR ECOL-NETH 2015. [DOI: 10.1007/s12080-015-0290-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Halliday WD, Gilmour KM, Blouin-Demers G. Faecal corticosterone metabolite concentrations are not a good predictor of habitat suitability for common gartersnakes. CONSERVATION PHYSIOLOGY 2015; 3:cov047. [PMID: 27293731 PMCID: PMC4778491 DOI: 10.1093/conphys/cov047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/02/2015] [Accepted: 09/11/2015] [Indexed: 06/06/2023]
Abstract
Measuring habitat suitability is important in conservation and in wildlife management. Measuring the abundance or presence-absence of a species in various habitats is not sufficient to measure habitat suitability because these metrics can be poor predictors of population success. Therefore, having some measure of population success is essential in assessing habitat suitability, but estimating population success is difficult. Identifying suitable proxies for population success could thus be beneficial. We examined whether faecal corticosterone metabolite (fCM) concentrations could be used as a proxy for habitat suitability in common gartersnakes (Thamnophis sirtalis). We conducted a validation study and confirmed that fCM concentrations indeed reflect circulating corticosterone concentrations. We estimated abundance, reproductive output and growth rate of gartersnakes in field and in forest habitat and we also measured fCM concentrations of gartersnakes from these same habitats. Common gartersnakes were more abundant and had higher reproductive outputs and higher growth rates in field habitat than in forest habitat, but fCM concentrations did not differ between the same two habitats. Our results suggest either that fCM concentrations are not a useful metric of habitat suitability in common gartersnakes or that the difference in suitability between the two habitats was too small to induce changes in fCM concentrations. Incorporating fitness metrics in estimates of habitat suitability is important, but these metrics of fitness have to be sensitive enough to vary between habitats.
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Affiliation(s)
- William D Halliday
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, Canada K1N 6N5
| | - Kathleen M Gilmour
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, Canada K1N 6N5
| | - Gabriel Blouin-Demers
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, Canada K1N 6N5
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29
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Matthiopoulos J, Fieberg J, Aarts G, Beyer HL, Morales JM, Haydon DT. Establishing the link between habitat selection and animal population dynamics. ECOL MONOGR 2015. [DOI: 10.1890/14-2244.1] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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30
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Post-establishment changes in habitat selection by an invasive species: beavers in the Patagonian steppe. Biol Invasions 2015. [DOI: 10.1007/s10530-015-0948-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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31
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LaManna JA, Hemenway AB, Boccadori V, Martin TE. Bird species turnover is related to changing predation risk along a vegetation gradient. Ecology 2015. [DOI: 10.1890/14-1333.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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32
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Flesch AD, Hutto RL, van Leeuwen WJD, Hartfield K, Jacobs S. Spatial, temporal, and density-dependent components of habitat quality for a desert owl. PLoS One 2015; 10:e0119986. [PMID: 25786257 PMCID: PMC4364994 DOI: 10.1371/journal.pone.0119986] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 01/23/2015] [Indexed: 11/22/2022] Open
Abstract
Spatial variation in resources is a fundamental driver of habitat quality but the realized value of resources at any point in space may depend on the effects of conspecifics and stochastic factors, such as weather, which vary through time. We evaluated the relative and combined effects of habitat resources, weather, and conspecifics on habitat quality for ferruginous pygmy-owls (Glaucidium brasilianum) in the Sonoran Desert of northwest Mexico by monitoring reproductive output and conspecific abundance over 10 years in and around 107 territory patches. Variation in reproductive output was much greater across space than time, and although habitat resources explained a much greater proportion of that variation (0.70) than weather (0.17) or conspecifics (0.13), evidence for interactions among each of these components of the environment was strong. Relative to habitat that was persistently low in quality, high-quality habitat buffered the negative effects of conspecifics and amplified the benefits of favorable weather, but did not buffer the disadvantages of harsh weather. Moreover, the positive effects of favorable weather at low conspecific densities were offset by intraspecific competition at high densities. Although realized habitat quality declined with increasing conspecific density suggesting interference mechanisms associated with an Ideal Free Distribution, broad spatial heterogeneity in habitat quality persisted. Factors linked to food resources had positive effects on reproductive output but only where nest cavities were sufficiently abundant to mitigate the negative effects of heterospecific enemies. Annual precipitation and brooding-season temperature had strong multiplicative effects on reproductive output, which declined at increasing rates as drought and temperature increased, reflecting conditions predicted to become more frequent with climate change. Because the collective environment influences habitat quality in complex ways, integrated approaches that consider habitat resources, stochastic factors, and conspecifics are necessary to accurately assess habitat quality.
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Affiliation(s)
- Aaron D. Flesch
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
- * E-mail:
| | - Richard L. Hutto
- Division of Biological Sciences, University of Montana, Missoula, Montana, United States of America
| | - Willem J. D. van Leeuwen
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America
| | - Kyle Hartfield
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America
| | - Sky Jacobs
- Watershed Management Group, Tucson, Arizona, United States of America
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33
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Newman AEM, Edmunds NB, Ferraro S, Heffell Q, Merritt GM, Pakkala JJ, Schilling CR, Schorno S. Using ecology to inform physiology studies: implications of high population density in the laboratory. Am J Physiol Regul Integr Comp Physiol 2015; 308:R449-54. [PMID: 25589015 DOI: 10.1152/ajpregu.00328.2014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Conspecific density is widely recognized as an important ecological factor across the animal kingdom; however, the physiological impacts are less thoroughly described. In fact, population density is rarely mentioned as a factor in physiological studies on captive animals and, when it is infrequently addressed, the animals used are reared and housed at densities far above those in nature, making the translation of results from the laboratory to natural systems difficult. We survey the literature to highlight this important ecophysiological gap and bring attention to the possibility that conspecific density prior to experimentation may be a critical factor influencing results. Across three taxa: mammals, birds, and fish, we present evidence from ecology that density influences glucocorticoid levels, immune function, and body condition with the intention of stimulating discussion and increasing consideration of population density in physiology studies. We conclude with several directives to improve the applicability of insights gained in the laboratory to organisms in the natural environment.
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Affiliation(s)
- Amy E M Newman
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Nicholas B Edmunds
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Shannon Ferraro
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Quentin Heffell
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Gillian M Merritt
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Jesse J Pakkala
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Cory R Schilling
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Sarah Schorno
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
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34
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Casini M, Rouyer T, Bartolino V, Larson N, Grygiel W. Density-dependence in space and time: opposite synchronous variations in population distribution and body condition in the Baltic Sea sprat (Sprattus sprattus) over three decades. PLoS One 2014; 9:e92278. [PMID: 24699501 PMCID: PMC3974706 DOI: 10.1371/journal.pone.0092278] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 02/20/2014] [Indexed: 11/18/2022] Open
Abstract
Spatio-temporal density-dependent processes are crucial regulatory factors for natural populations. However, there is a lack of studies addressing spatial density-dependence in fish growth. A previous investigation has suggested spatio-temporal density-dependence in body condition of Baltic sprat. Here, we used different techniques, such as centre of gravity, distance, and homogeneity indices, to better characterize the spatial and temporal variations in sprat density and body condition in the Baltic Proper. Our results evidenced a negative spatio-temporal co-variation between the centres of gravity of density and maximum condition. In the 1980s-early 1990s both centres were located in the middle of the Baltic Proper. From the mid 1990s the centres progressively separated in space, as the sprat population moved towards the north-eastern Baltic Proper, and the centre of maximum condition towards the south-western areas. Moreover, at low abundances, sprat density and condition were homogeneously distributed in space, whereas at high abundances both density and condition showed pronounced geographical gradients. The ecological processes potentially explaining the observed patterns were discussed in the light of the Ideal Free Distribution theory. We provide evidence that the shift in the spatial distribution of cod, the main predator of sprat, has been the main factor triggering the overall spatial changes in sprat density, and thus condition, during the past thirty years. The spatial indices shown here, synthesizing the spatio-temporal patterns of fish distribution, can support the implementation of the EU Marine Strategy Framework Directive.
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Affiliation(s)
- Michele Casini
- Swedish University of Agricultural Sciences, Department of Aquatic Resources, Institute of Marine Research, Lysekil, Sweden
- * E-mail:
| | - Tristan Rouyer
- University of Oslo, Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, Oslo, Norway
- UMR 212 EME, IFREMER (Institut Français de Recherche pour l'Exploitation de la mer), Sète, France
| | - Valerio Bartolino
- Swedish University of Agricultural Sciences, Department of Aquatic Resources, Institute of Marine Research, Lysekil, Sweden
- University of Gothenburg, Department of Earth Sciences, Gothenburg, Sweden
| | - Niklas Larson
- Swedish University of Agricultural Sciences, Department of Aquatic Resources, Institute of Marine Research, Lysekil, Sweden
| | - Włodzimierz Grygiel
- National Marine Fisheries Research Institute (NMFRI), Department of Fisheries Resources, Gdynia, Poland
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Tarjuelo R, Morales MB, Traba J, Delgado MP. Are species coexistence areas a good option for conservation management? Applications from fine scale modelling in two steppe birds. PLoS One 2014; 9:e87847. [PMID: 24498210 PMCID: PMC3909229 DOI: 10.1371/journal.pone.0087847] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 01/03/2014] [Indexed: 11/19/2022] Open
Abstract
Biotic interactions and land uses have been proposed as factors that determine the distribution of the species at local scale. The presence of heterospecifics may modify the habitat selection pattern of the individuals and this may have important implications for the design of effective conservation strategies. However, conservation proposals are often focused on a single flagship or umbrella species taken as representative of an entire assemblage requirements. Our aim is to identify and evaluate the role of coexistence areas at local scale as conservation tools, by using distribution data of two endangered birds, the Little Bustard and the Great Bustard. Presence-only based suitability models for each species were built with MaxEnt using variables of substrate type and topography. Probability maps of habitat suitability for each species were combined to generate a map in which coexistence and exclusive use areas were delimitated. Probabilities of suitable habitat for each species inside coexistence and exclusive areas were compared. As expected, habitat requirements of Little and Great Bustards differed. Coexistence areas presented lower probabilities of habitat suitability than exclusive use ones. We conclude that differences in species' habitat preferences can hinder the efficiency of protected areas with multi-species conservation purposes. Our results highlight the importance of taking into account the role of biotic interactions when designing conservation measurements.
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Affiliation(s)
- Rocío Tarjuelo
- Terrestrial Ecology Group (TEG), Department of Ecology, Universidad Autónoma de Madrid, Madrid, Spain
- * E-mail:
| | - Manuel B. Morales
- Terrestrial Ecology Group (TEG), Department of Ecology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Juan Traba
- Terrestrial Ecology Group (TEG), Department of Ecology, Universidad Autónoma de Madrid, Madrid, Spain
| | - M. Paula Delgado
- Terrestrial Ecology Group (TEG), Department of Ecology, Universidad Autónoma de Madrid, Madrid, Spain
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Lok T, Overdijk O, Piersma T. Migration Tendency Delays Distributional Response to Differential Survival Prospects along a Flyway. Am Nat 2013; 181:520-31. [DOI: 10.1086/669679] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Jonzén N. Habitat Selection: Implications for Monitoring, Management, and Conservation. Isr J Ecol Evol 2013. [DOI: 10.1560/ijee.54.3-4.459] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Knight TW, Morris DW, Haedrich RL. Inferring Competitive Behavior from Population Census and Habitat Data. Isr J Ecol Evol 2013. [DOI: 10.1560/ijee.54.3-4.345] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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39
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Prey selectivity affects reproductive success of a corallivorous reef fish. Oecologia 2012; 172:409-16. [DOI: 10.1007/s00442-012-2521-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2012] [Accepted: 10/23/2012] [Indexed: 10/27/2022]
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40
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Klein GP, Cameron GN. Effect of habitat gradients on space use by white-footed mice (Peromyscus leucopus). J Mammal 2012. [DOI: 10.1644/11-mamm-a-258.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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van der Hammen T, Montserrat M, Sabelis MW, de Roos AM, Janssen A. Whether ideal free or not, predatory mites distribute so as to maximize reproduction. Oecologia 2012; 169:95-104. [PMID: 22081260 PMCID: PMC3326238 DOI: 10.1007/s00442-011-2190-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Accepted: 10/17/2011] [Indexed: 12/02/2022]
Abstract
Ideal free distribution (IFD) models predict that animals distribute themselves such that no individual can increase its fitness by moving to another patch. Many empirical tests assume that the interference among animals is independent of density and do not quantify the effects of density on fitness traits. Using two species of predatory mites, we measured oviposition as a function of conspecific density. Subsequently, we used these functions to calculate expected distributions on two connected patches. We performed an experimental test of the distributions of mites on two such connected patches, among which one had a food accessibility rate that was twice as high as on the other. For one of the two species, Iphiseius degenerans, the distribution matched the expected distribution. The distribution also coincided with the ratio of food accessibility. The other species, Neoseiulus cucumeris, distributed itself differently than expected. However, the oviposition rates of both species did not differ significantly from the expected oviposition rates based on experiments on single patches. This suggests that the oviposition rate of N. cucumeris was not negatively affected by the observed distribution, despite the fact that N. cucumeris did not match the predicted distributions. Thus, the distribution of one mite species, I. degenerans, was in agreement with IFD theory, whereas for the other mite species, N. cucumeris, unknown factors may have influenced the distribution of the mites. We conclude that density-dependent fitness traits provide essential information for explaining animal distributions.
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Paterson J, Steinberg B, Litzgus J. Generally specialized or especially general? Habitat selection by Snapping Turtles (Chelydra serpentina) in central Ontario. CAN J ZOOL 2012. [DOI: 10.1139/z11-118] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Habitat selection is the disproportionate use of habitat compared with availability. Many studies have focused on specialists, but few have considered habitat selection in populations that are generalists, which can be composed of generalist individuals or individuals that specialize on different habitats. We tested habitat selection and individual specialization in a northern population of a supposed generalist, the Snapping Turtle ( Chelydra serpentina (L., 1758)), during the active season and winter using telemetry. Habitat selection was tested at two spatial scales by comparing random points to home ranges and turtle locations using Euclidean distances. Turtles selected home ranges from the habitats available in the population range. However, at the population level, all aquatic habitats were equally preferred, and the population behaved as a generalist owing to individuals specialized on different habitats. Over half of the individuals showed evidence of individual specialization on different habitat types. Turtles did not select habitat within home ranges during the active season, but overwintering turtles chose locations that were colder than haphazard stations in the same habitats, likely to reduce metabolic costs and the risk of acidosis. These findings have implications for the management of this species at risk and for understanding the evolution of resource generalization.
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Affiliation(s)
- J.E. Paterson
- Department of Biology, Laurentian University, 935 Ramsey Lake Road, Sudbury, ON P3E 2C6, Canada
| | - B.D. Steinberg
- Ontario Ministry of Natural Resources, Algonquin Provincial Park, P.O. Box 219, Whitney, ON K0J 2M0, Canada
| | - J.D. Litzgus
- Department of Biology, Laurentian University, 935 Ramsey Lake Road, Sudbury, ON P3E 2C6, Canada
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Fuxjager MJ, Montgomery JL, Becker EA, Marler CA. Deciding to win: interactive effects of residency, resources and ‘boldness’ on contest outcome in white-footed mice. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2010.08.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Gaillard JM, Hebblewhite M, Loison A, Fuller M, Powell R, Basille M, Van Moorter B. Habitat-performance relationships: finding the right metric at a given spatial scale. Philos Trans R Soc Lond B Biol Sci 2010; 365:2255-65. [PMID: 20566502 DOI: 10.1098/rstb.2010.0085] [Citation(s) in RCA: 217] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The field of habitat ecology has been muddled by imprecise terminology regarding what constitutes habitat, and how importance is measured through use, selection, avoidance and other bio-statistical terminology. Added to the confusion is the idea that habitat is scale-specific. Despite these conceptual difficulties, ecologists have made advances in understanding 'how habitats are important to animals', and data from animal-borne global positioning system (GPS) units have the potential to help this clarification. Here, we propose a new conceptual framework to connect habitats with measures of animal performance itself--towards assessing habitat-performance relationship (HPR). Long-term studies will be needed to estimate consequences of habitat selection for animal performance. GPS data from wildlife can provide new approaches for studying useful correlates of performance that we review. Recent examples include merging traditional resource selection studies with information about resources used at different critical life-history events (e.g. nesting, calving, migration), uncovering habitats that facilitate movement or foraging and, ultimately, comparing resources used through different life-history strategies with those resulting in death. By integrating data from GPS receivers with other animal-borne technologies and combining those data with additional life-history information, we believe understanding the drivers of HPRs will inform animal ecology and improve conservation.
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Affiliation(s)
- Jean-Michel Gaillard
- Unité Mixte de Recherche CNRS-Université Lyon 1 N degrees 5558 Biométrie et Biologie Evolutive, Bâtiment Gregor Mendel, 43 boulevard du 11 novembre 1918, 69622 Villeurbanne Cedex, France.
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Krüger O, Lindström J. Habitat heterogeneity affects population growth in goshawk Accipiter gentilis. J Anim Ecol 2008. [DOI: 10.1111/j.1365-2656.2001.00481.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lindberg WJ, Frazer TK, Portier KM, Vose F, Loftin J, Murie DJ, Mason DM, Nagy B, Hart MK. Density-dependent habitat selection and performance by a large mobile reef fish. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2006; 16:731-46. [PMID: 16711059 DOI: 10.1890/1051-0761(2006)016[0731:dhsapb]2.0.co;2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Many exploited reef fish are vulnerable to overfishing because they concentrate over hard-bottom patchy habitats. How mobile reef fish use patchy habitat, and the potential consequences on demographic parameters, must be known for spatially explicit population dynamics modeling, for discriminating essential fish habitat (EFH), and for effectively planning conservation measures (e.g., marine protected areas, stock enhancement, and artificial reefs). Gag, Mycteroperca microlepis, is an ecologically and economically important warm-temperate grouper in the southeastern United States, with behavioral and life history traits conducive to large-scale field experiments. The Suwannee Regional Reef System (SRRS) was built of standard habitat units (SHUs) in 1991-1993 to manipulate and control habitat patchiness and intrinsic habitat quality, and thereby test predictions from habitat selection theory. Colonization of the SRRS by gag over the first six years showed significant interactions of SHU size, spacing, and reef age; with trajectories modeled using a quadratic function for closely spaced SHUs (25 m) and a linear model for widely spaced SHUs (225 m), with larger SHUs (16 standardized cubes) accumulating significantly more gag faster than smaller 4-cube SHUs (mean = 72.5 gag/16-cube SHU at 225-m spacing by year 6, compared to 24.2 gag/4-cube SHU for same spacing and reef age). Residency times (mean = 9.8 mo), indicative of choice and measured by ultrasonic telemetry (1995-1998), showed significant interaction of SHU size and spacing consistent with colonization trajectories. Average relative weight (W(r)) and incremental growth were greater on smaller than larger SHUs (mean W(r) = 104.2 vs. 97.7; incremental growth differed by 15%), contrary to patterns of abundance and residency. Experimental manipulation of shelter on a subset of SRRS sites (2000-2001) confirmed our hypothesis that shelter limits local densities of gag, which, in turn, regulates their growth and condition. Density-dependent habitat selection for shelter and individual growth dynamics were therefore interdependent ecological processes that help to explain how patchy reef habitat sustains gag production. Moreover, gag selected shelter at the expense of maximizing their growth. Thus, mobile reef fishes could experience density-dependent effects on growth, survival, and/or reproduction (i.e., demographic parameters) despite reduced stock sizes as a consequence of fishing.
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Affiliation(s)
- William J Lindberg
- Department of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st Street, Gainesville, Florida 32653, USA.
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Emlen JM, Duda JJ, Kirchhoff MD, Freeman DC. Interaction Assessment: A modeling tool for predicting population dynamics from field data. Ecol Modell 2006. [DOI: 10.1016/j.ecolmodel.2005.07.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Burns CE. Behavioral ecology of disturbed landscapes: the response of territorial animals to relocation. Behav Ecol 2005. [DOI: 10.1093/beheco/ari070] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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W. Morris D, E. Diffendorfer J, Lundberg P. Dispersal among habitats varying in fitness: reciprocating migration through ideal habitat selection. OIKOS 2004. [DOI: 10.1111/j.0030-1299.2004.12894.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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