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Uiterwaal SF, DeLong JP. Foraging rates from metabarcoding: Predators have reduced functional responses in wild, diverse prey communities. Ecol Lett 2024; 27:e14394. [PMID: 38511320 DOI: 10.1111/ele.14394] [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: 09/18/2023] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 03/22/2024]
Abstract
Functional responses describe foraging rates across prey densities and underlie many fundamental ecological processes. Most functional response knowledge comes from simplified lab experiments, but we do not know whether these experiments accurately represent foraging in nature. In addition, the difficulty of conducting multispecies functional response experiments means that it is unclear whether interaction strengths are weakened in the presence of multiple prey types. We developed a novel method to estimate wild predators' foraging rates from metabarcoding data and use this method to present functional responses for wild wolf spiders foraging on 27 prey families. These field functional responses were considerably reduced compared to lab functional responses. We further find that foraging is sometimes increased in the presence of other prey types, contrary to expectations. Our novel method for estimating field foraging rates will allow researchers to determine functional responses for wild predators and address long-standing questions about foraging in nature.
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Affiliation(s)
- Stella F Uiterwaal
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
- Living Earth Collaborative, Washington University in St. Louis, St. Louis, Missouri, USA
- Institute for Conservation Medicine, Saint Louis Zoo, St. Louis, Missouri, USA
- National Great Rivers Research and Education Center, East Alton, Illinois, USA
- Department of Biology, Saint Louis University, St. Louis, Missouri, USA
| | - John P DeLong
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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2
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Beardsell A, Berteaux D, Dulude-De Broin F, Gauthier G, Clermont J, Gravel D, Bêty J. Predator-mediated interactions through changes in predator home range size can lead to local prey exclusion. Proc Biol Sci 2023; 290:20231154. [PMID: 37554032 PMCID: PMC10410220 DOI: 10.1098/rspb.2023.1154] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 07/12/2023] [Indexed: 08/10/2023] Open
Abstract
The strength of indirect biotic interactions is difficult to quantify in the wild and can alter community composition. To investigate whether the presence of a prey species affects the population growth rate of another prey species, we quantified predator-mediated interaction strength using a multi-prey mechanistic model of predation and a population matrix model. Models were parametrized using behavioural, demographic and experimental data from a vertebrate community that includes the arctic fox (Vulpes lagopus), a predator feeding on lemmings and eggs of various species such as sandpipers and geese. We show that the positive effects of the goose colony on sandpiper nesting success (due to reduction of search time for sandpiper nests) were outweighed by the negative effect of an increase in fox density. The fox numerical response was driven by changes in home range size. As a result, the net interaction from the presence of geese was negative and could lead to local exclusion of sandpipers. Our study provides a rare empirically based model that integrates mechanistic multi-species functional responses and behavioural processes underlying the predator numerical response. This is an important step forward in our ability to quantify the consequences of predation for community structure and dynamics.
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Affiliation(s)
- Andréanne Beardsell
- Chaire de recherche du Canada en biodiversité nordique, Centre d'études nordiques et Centre de la science de la biodiversité du Québec, Université du Québec à Rimouski, Rimouski, Québec, Canada G5L 3A1
| | - Dominique Berteaux
- Chaire de recherche du Canada en biodiversité nordique, Centre d'études nordiques et Centre de la science de la biodiversité du Québec, Université du Québec à Rimouski, Rimouski, Québec, Canada G5L 3A1
| | | | - Gilles Gauthier
- Département de biologie et Centre d'études nordiques, Université Laval, Québec, Canada G1V 0A6
| | - Jeanne Clermont
- Chaire de recherche du Canada en biodiversité nordique, Centre d'études nordiques et Centre de la science de la biodiversité du Québec, Université du Québec à Rimouski, Rimouski, Québec, Canada G5L 3A1
| | - Dominique Gravel
- Département de biologie et Centre d'études nordiques, Université de Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1
| | - Joël Bêty
- Chaire de recherche du Canada en biodiversité nordique, Centre d'études nordiques et Centre de la science de la biodiversité du Québec, Université du Québec à Rimouski, Rimouski, Québec, Canada G5L 3A1
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3
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Pakanen V, Tornberg R, Airaksinen E, Rönkä N, Koivula K. The abundance of small mammals is positively linked to survival from nest depredation but negatively linked to local recruitment of a ground nesting precocial bird. Ecol Evol 2022; 12:e9292. [PMID: 36110877 PMCID: PMC9465198 DOI: 10.1002/ece3.9292] [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: 02/15/2022] [Revised: 08/15/2022] [Accepted: 08/19/2022] [Indexed: 12/02/2022] Open
Abstract
Generalist predators using small mammals as their primary prey are suggested to shift hunting alternative prey such as bird nests, when small mammals are in short supply (the alternative prey hypothesis, APH). Nest survival and survival of young individuals should be positively linked to small mammal abundance and negatively linked to predator abundance, but little information exists from survival of chicks, especially until recruitment. We test these predictions of the APH using 13 years (2002-2014) of life history data from a ground nesting shorebird breeding on coastal meadows. We use small mammal abundance in the previous autumn as a proxy for spring predator abundance, mainly of mammalian predators. We examine whether small mammal abundance in the spring and previous autumn explain annual variation in nest survival from depredation and local recruitment of the southern dunlin Calidris alpina schinzii. As predicted by the APH, survival from nest predation was positively linked to spring small mammal abundance and negatively linked to autumn small mammal abundance. Importantly, local recruitment showed opposite responses. This counterintuitive result may be explained by density-dependent survival. When nest depredation rates are low, predators may show stronger numerical and functional responses to high shorebird chick abundance on coastal meadows, whereas in years of high nest depredation, few hatching chicks lure fewer predators. The opposite effects on nest and local recruitment demonstrate the diverse mechanisms by which population size variation in primary prey can affect dynamics of alternative prey populations.
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Affiliation(s)
| | - Risto Tornberg
- Ecology and Genetics Research UnitUniversity of OuluOuluFinland
| | | | - Nelli Rönkä
- Ecology and Genetics Research UnitUniversity of OuluOuluFinland
| | - Kari Koivula
- Ecology and Genetics Research UnitUniversity of OuluOuluFinland
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Beardsell A, Gravel D, Clermont J, Berteaux D, Gauthier G, Bêty J. A mechanistic model of functional response provides new insights into indirect interactions among arctic tundra prey. Ecology 2022; 103:e3734. [DOI: 10.1002/ecy.3734] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/07/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Andréanne Beardsell
- Chaire de recherche du Canada en biodiversité nordique, Centre d’études nordiques et Centre de la science de la biodiversité du Québec Université du Québec à Rimouski Rimouski Québec Canada
| | - Dominique Gravel
- Département de biologie et Centre d’études nordiques Université de Sherbrooke Sherbrooke Québec Canada
| | - Jeanne Clermont
- Chaire de recherche du Canada en biodiversité nordique, Centre d’études nordiques et Centre de la science de la biodiversité du Québec Université du Québec à Rimouski Rimouski Québec Canada
| | - Dominique Berteaux
- Chaire de recherche du Canada en biodiversité nordique, Centre d’études nordiques et Centre de la science de la biodiversité du Québec Université du Québec à Rimouski Rimouski Québec Canada
| | - Gilles Gauthier
- Département de biologie et Centre d’études nordiques Université Laval Québec Québec Canada
| | - Joël Bêty
- Chaire de recherche du Canada en biodiversité nordique, Centre d’études nordiques et Centre de la science de la biodiversité du Québec Université du Québec à Rimouski Rimouski Québec Canada
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Boyce PN, McLoughlin PD. Ecological Interactions Involving Feral Horses and Predators: Review with Implications for Biodiversity Conservation. J Wildl Manage 2021. [DOI: 10.1002/jwmg.21995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Paul N. Boyce
- Department of Biology University of Saskatchewan 112 Science Place Saskatoon SK S7N 5E2 Canada
| | - Philip D. McLoughlin
- Department of Biology University of Saskatchewan 112 Science Place Saskatoon SK S7N 5E2 Canada
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Introduced lagomorph produce stronger potential apparent competition in invaded communities than any other species in a similar but native food web. Biol Invasions 2019. [DOI: 10.1007/s10530-019-02082-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Montagano L, Leroux SJ, Giroux M, Lecomte N. The strength of ecological subsidies across ecosystems: a latitudinal gradient of direct and indirect impacts on food webs. Ecol Lett 2018; 22:265-274. [DOI: 10.1111/ele.13185] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/06/2018] [Accepted: 10/23/2018] [Indexed: 11/28/2022]
Affiliation(s)
- Laurent Montagano
- Department of Biology Université de Moncton Moncton New BrunswickE1A 3E9 Canada
- Canada Research Chair in Polar and Boreal Ecology and Centre d’études nordiques Université de Moncton Moncton New Brunswick E1A 3E9 Canada
| | - Shawn J. Leroux
- Department of Biology Memorial University St‐John's, Newfoundland and LabradorA1B 3X9 Canada
| | - Marie‐Andrée Giroux
- K.‐C.‐Irving Chair in Environmental Sciences and Sustainable Development Université de Moncton Moncton New BrunswickE1A 3E9 Canada
| | - Nicolas Lecomte
- Department of Biology Université de Moncton Moncton New BrunswickE1A 3E9 Canada
- Canada Research Chair in Polar and Boreal Ecology and Centre d’études nordiques Université de Moncton Moncton New Brunswick E1A 3E9 Canada
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8
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Barraquand F, Nielsen ÓK. Predator-prey feedback in a gyrfalcon-ptarmigan system? Ecol Evol 2018; 8:12425-12434. [PMID: 30619555 PMCID: PMC6308892 DOI: 10.1002/ece3.4563] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 07/23/2018] [Accepted: 08/19/2018] [Indexed: 11/30/2022] Open
Abstract
Specialist predators with oscillating dynamics are often strongly affected by the population dynamics of their prey, yet they are not always the cause of prey cycling. Only those that exert strong (delayed) regulation of their prey can be. Inferring predator-prey coupling from time series therefore requires contrasting models with top-down versus bottom-up predator-prey dynamics. We study here the joint dynamics of population densities of the Icelandic gyrfalcon Falco rusticolus, and its prey, the rock ptarmigan Lagopus muta. The dynamics of both species are likely not only linked to each other but also to stochastic weather variables acting as confounding factors. We infer the degree of coupling between populations, as well as forcing by abiotic variables, using multivariate autoregressive models MAR(p), with p = 1 and 2 time lags. MAR(2) models, allowing for species to cycle independently from each other, further suggest alternative scenarios where a cyclic prey influences its predator but not the other way around (i.e., bottom-up scenarios). The classical MAR(1) model predicts that the time series exhibit predator-prey feedback (i.e., reciprocal dynamic influence between prey and predator), and that weather effects are weak and only affecting the gyrfalcon population. Bottom-up MAR(2) models produced a better fit but less realistic cross-correlation patterns. Simulations of MAR(1) and MAR(2) models further demonstrate that the top-down MAR(1) models are more likely to be misidentified as bottom-up dynamics than vice versa. We therefore conclude that predator-prey feedback in the gyrfalcon-ptarmigan system is likely the main cause of observed oscillations, though bottom-up dynamics cannot yet be excluded with certainty. Overall, we showed how to make more out of ecological time series by using simulations to gauge the quality of model identification, and paved the way for more mechanistic modeling of this system by narrowing the set of important biotic and abiotic drivers.
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Affiliation(s)
- Frédéric Barraquand
- CNRSInstitute of Mathematics of BordeauxTalenceFrance
- Integrative and Theoretical Ecology, LabEx COTEUniversity of BordeauxPessacFrance
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9
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Barraquand F, Picoche C, Maurer D, Carassou L, Auby I. Coastal phytoplankton community dynamics and coexistence driven by intragroup density-dependence, light and hydrodynamics. OIKOS 2018. [DOI: 10.1111/oik.05361] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- F. Barraquand
- Univ. of Bordeaux, Integrative and Theoretical Ecology, LabEx COTE; Bât. B2 - Allée Geoffroy St-Hilaire FR-33615 Pessac France
- CNRS, Inst. of Mathematics of Bordeaux; Talence France
| | - C. Picoche
- Univ. of Bordeaux, Integrative and Theoretical Ecology, LabEx COTE; Bât. B2 - Allée Geoffroy St-Hilaire FR-33615 Pessac France
| | - D. Maurer
- Ifremer, LER Arcachon, Quai du Commandant Silhouette; Arcachon France
| | - L. Carassou
- Univ. of Bordeaux, Integrative and Theoretical Ecology, LabEx COTE; Bât. B2 - Allée Geoffroy St-Hilaire FR-33615 Pessac France
- Irstea, Aquatic ecosystems and global changes Unit (UR EABX); Cestas France
| | - I. Auby
- Ifremer, LER Arcachon, Quai du Commandant Silhouette; Arcachon France
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10
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High goose abundance reduces nest predation risk in a simple rodent-free high-Arctic ecosystem. Polar Biol 2017. [DOI: 10.1007/s00300-017-2223-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Abstract
Most species have one or more natural enemies, e.g., predators, parasites, pathogens, and herbivores, among others. These species in turn typically attack multiple victim species. This leads to the possibility of indirect interactions among those victims, both positive and negative. The term apparent competition commonly denotes negative indirect interactions between victim species that arise because they share a natural enemy. This indirect interaction, which in principle can be reflected in many facets of the distribution and abundance of individual species and more broadly govern the structure of ecological communities in time and space, pervades many natural ecosystems. It also is a central theme in many applied ecological problems, including the control of agricultural pests, harvesting, the conservation of endangered species, and the dynamics of emerging diseases. At one end of the scale of life, apparent competition characterizes intriguing aspects of dynamics within individual organisms—for example, the immune system is akin in many ways to a predator that can induce negative indirect interactions among different pathogens. At intermediate scales of biological organization, the existence and strength of apparent competition depend upon many contingent details of individual behavior and life history, as well as the community and spatial context within which indirect interactions play out. At the broadest scale of macroecology and macroevolution, apparent competition may play a major, if poorly understood, role in the evolution of species’ geographical ranges and adaptive radiations.
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Affiliation(s)
- Robert D. Holt
- Department of Biology, University of Florida, Gainesville, Florida 32611 USA
| | - Michael B. Bonsall
- Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom
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Barraquand F, Louca S, Abbott KC, Cobbold CA, Cordoleani F, DeAngelis DL, Elderd BD, Fox JW, Greenwood P, Hilker FM, Murray DL, Stieha CR, Taylor RA, Vitense K, Wolkowicz GS, Tyson RC. Moving forward in circles: challenges and opportunities in modelling population cycles. Ecol Lett 2017. [DOI: 10.1111/ele.12789] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Frédéric Barraquand
- Department of Arctic and Marine Biology University of Tromsø Tromsø Norway
- Integrative and Theoretical Ecology Chair, LabEx COTE University of Bordeaux Pessac France
| | - Stilianos Louca
- Institute of Applied Mathematics University of British Columbia Vancouver BC Canada
| | - Karen C. Abbott
- Department of Biology Case Western Reserve University Cleveland OH USA
| | | | - Flora Cordoleani
- Institute of Marine Science University of California Santa Cruz Santa Cruz CA USA
- Southwest Fisheries Science Center Santa Cruz CA USA
| | | | - Bret D. Elderd
- Department of Biological Sciences Lousiana State University Baton Rouge LA USA
| | - Jeremy W. Fox
- Department of Biological Sciences University of Calgary Calgary ABCanada
| | | | - Frank M. Hilker
- Institute of Environmental Systems Research, School of Mathematics/Computer Science Osnabrück University Osnabrück Germany
| | - Dennis L. Murray
- Integrative Wildlife Conservation Lab Trent University Peterborough ONCanada
| | - Christopher R. Stieha
- Department of Biology Case Western Reserve University Cleveland OH USA
- Department of Entomology Cornell University Ithaca NY USA
| | - Rachel A. Taylor
- Department of Integrative Biology University of South Florida Tampa FLUSA
| | - Kelsey Vitense
- Department of Fisheries, Wildlife, and Conservation Biology University of Minnesota Saint Paul MN USA
| | - Gail S.K. Wolkowicz
- Department of Mathematics and Statistics McMaster University Hamilton ON Canada
| | - Rebecca C. Tyson
- Department of Mathematics and Statistics University of British Columbia Okanagan Kelowna BC Canada
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Liang H, Li N, Chen Z. The Prey Tactics by Two Owl Species in the Forest of Northeastern China. FOLIA ZOOLOGICA 2016. [DOI: 10.25225/fozo.v65.i3.a5.2016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Hongchun Liang
- Department of Plant Protection, Tianjin Agricultural University, 22 Jinjinglu, Xiqing, Tianjin 300384, China
| | - Ning Li
- Department of Plant Protection, Tianjin Agricultural University, 22 Jinjinglu, Xiqing, Tianjin 300384, China
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Lee DE, Kissui BM, Kiwango YA, Bond ML. Migratory herds of wildebeests and zebras indirectly affect calf survival of giraffes. Ecol Evol 2016; 6:8402-8411. [PMID: 28031792 PMCID: PMC5167056 DOI: 10.1002/ece3.2561] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Revised: 09/14/2016] [Accepted: 09/22/2016] [Indexed: 11/24/2022] Open
Abstract
In long‐distance migratory systems, local fluctuations in the predator–prey ratio can exhibit extreme variability within a single year depending upon the seasonal location of migratory species. Such systems offer an opportunity to empirically investigate cyclic population density effects on short‐term food web interactions by taking advantage of the large seasonal shifts in migratory prey biomass. We utilized a large‐mammal predator–prey savanna food web to evaluate support for hypotheses relating to the indirect effects of “apparent competition” and “apparent mutualism” from migratory ungulate herds on survival of resident megaherbivore calves, mediated by their shared predator. African lions (Panthera leo) are generalist predators whose primary, preferred prey are wildebeests (Connochaetes taurinus) and zebras (Equus quagga), while lion predation on secondary prey such as giraffes (Giraffa camelopardalis) may change according to the relative abundance of the primary prey species. We used demographic data from five subpopulations of giraffes in the Tarangire Ecosystem of Tanzania, East Africa, to test hypotheses relating to direct predation and indirect effects of large migratory herds on calf survival of a resident megaherbivore. We examined neonatal survival via apparent reproduction of 860 adult females, and calf survival of 449 giraffe calves, during three precipitation seasons over 3 years, seeking evidence of some effect on neonate and calf survival as a consequence of the movements of large herds of migratory ungulates. We found that local lion predation pressure (lion density divided by primary prey density) was significantly negatively correlated with giraffe neonatal and calf survival probabilities. This supports the apparent mutualism hypothesis that the presence of migratory ungulates reduces lion predation on giraffe calves. Natural predation had a significant effect on giraffe calf and neonate survival, and could significantly affect giraffe population dynamics. If wildebeest and zebra populations in this ecosystem continue to decline as a result of increasingly disrupted migrations and poaching, then giraffe calves will face increased predation pressure as the predator–prey ratio increases. Our results suggest that the widespread population declines observed in many migratory systems are likely to trigger demographic impacts in other species due to indirect effects like those shown here.
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Pöysä H, Jalava K, Paasivaara A. Generalist predator, cyclic voles and cavity nests: testing the alternative prey hypothesis. Oecologia 2016; 182:1083-1093. [PMID: 27665542 DOI: 10.1007/s00442-016-3728-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 09/08/2016] [Indexed: 10/21/2022]
Abstract
The alternative prey hypothesis (APH) states that when the density of the main prey declines, generalist predators switch to alternative prey and vice versa, meaning that predation pressure on the alternative prey should be negatively correlated with the density of the main prey. We tested the APH in a system comprising one generalist predator (pine marten, Martes martes), cyclic main prey (microtine voles, Microtus agrestis and Myodes glareolus) and alternative prey (cavity nests of common goldeneye, Bucephala clangula); pine marten is an important predator of both voles and common goldeneye nests. Specifically, we studied whether annual predation rate of real common goldeneye nests and experimental nests is negatively associated with fluctuation in the density of voles in four study areas in southern Finland in 2000-2011. Both vole density and nest predation rate varied considerably between years in all study areas. However, we did not find support for the hypothesis that vole dynamics indirectly affects predation rate of cavity nests in the way predicted by the APH. On the contrary, the probability of predation increased with vole spring abundance for both real and experimental nests. Furthermore, a crash in vole abundance from previous autumn to spring did not increase the probability of predation of real nests, although it increased that of experimental nests. We suggest that learned predation by pine marten individuals, coupled with efficient search image for cavities, overrides possible indirect positive effects of high vole density on the alternative prey in our study system.
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Affiliation(s)
- Hannu Pöysä
- Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Yliopistokatu 6, FI-80100, Joensuu, Finland.
| | - Kaisa Jalava
- Department of Biology, University of Eastern Finland, P.O. Box 111, FI-80101, Joensuu, Finland
| | - Antti Paasivaara
- Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Paavo Havaksentie 3, FI-90570, Oulu, Finland
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