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Paul S, Shahar N, Seifan M, Bar‐David S. An experimental design for obtaining DNA of a target species and its diet from a single non-invasive genetic protocol. Ecol Evol 2023; 13:e10616. [PMID: 37877104 PMCID: PMC10590962 DOI: 10.1002/ece3.10616] [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: 03/30/2023] [Revised: 09/02/2023] [Accepted: 10/04/2023] [Indexed: 10/26/2023] Open
Abstract
Next-generation sequencing technology has enabled accurate insights into the diet of wildlife species. The protocols for faecal sample collection and DNA extraction for diet analysis have differed from those focusing on target species, even in most studies combining questions on both aspects. We designed an experiment to evaluate two protocols using 11 parameters and select a single one that will generate both target species (Asiatic wild ass, Equus hemionus, in Israel) and diet DNA, as an effective strategy to minimise time, effort, and cost without hampering efficiency. In Protocol A, we swabbed the outer surface of faecal boluses and extracted DNA using a Stool Kit, while for Protocol B, we homogenised faecal matter from inside the bolus followed by extraction using a Powersoil Kit. Protocol A performed significantly better for four parameters, which included, for the target species, microsatellite amplification success and the quantity of the GAPDH gene; and for its diet, the number of exact sequence variants (ESVs) obtained at genus level and plant genus richness. However, there was no significant difference in the amplification success of sex-linked and plant markers, total reads at genus level, number of genera obtained and plant genus composition. Although we chose Protocol A, both protocols yielded results for the target species and its diet, demonstrating that one single protocol can be used for both purposes, although a pilot study is recommended to optimise the protocol for specific systems. This strategy may also be useful for studies combining target species and their gut microbiome and parasitic load.
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Affiliation(s)
- Shrutarshi Paul
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
| | - Naama Shahar
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
| | - Merav Seifan
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
| | - Shirli Bar‐David
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
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2
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Crowther MS, Rus AI, Mella VSA, Krockenberger MB, Lindsay J, Moore BD, McArthur C. Patch quality and habitat fragmentation shape the foraging patterns of a specialist folivore. Behav Ecol 2022; 33:1007-1017. [DOI: 10.1093/beheco/arac068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 06/17/2022] [Accepted: 06/28/2022] [Indexed: 11/14/2022] Open
Abstract
Abstract
Research on use of foraging patches has focused on why herbivores visit or quit patches, yet little is known about visits to patches over time. Food quality, as reflected by higher nutritional quality and lower plant defenses, and physical patch characteristics, which offer protection from predators and weather, affect patch use and hence should influence their revisitation. Due to the potentially high costs of moving between patches, fragmented habitats are predicted to complicate foraging decisions of many animals. We aimed to determine how food quality, shelter availability and habitat fragmentation influence tree reuse by a specialist folivore, the koala, in a fragmented agricultural landscape. We GPS-tracked 23 koalas in northern New South Wales, Australia and collated number of revisits, average residence time, and average time-to-return to each tree. We measured tree characteristics including food quality (foliar nitrogen and toxic formylated phloroglucinol compounds, FPCs concentrations), tree size, and tree connectedness. We also modeled the costs of locomotion between trees. Koalas re-visited isolated trees with high leaf nitrogen disproportionately often. They spent longer time in trees with high leaf nitrogen, and in large trees used for shelter. They took longer to return to trees with low leaf nitrogen. Tree connectivity reduced travel costs between patches, being either individual or groups of trees. FPC levels had no detectable effect on patch revisitation. We conclude that food quality and shelter drive koala tree re-visits. Scattered, isolated trees with nutrient-rich leaves are valuable resource patches for koalas despite movement costs to reach them.
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Affiliation(s)
- Mathew S Crowther
- School of Life and Environmental Sciences, University of Sydney , Sydney, New South Wales 2006 , Australia
| | - Adrian I Rus
- School of Life and Environmental Sciences, University of Sydney , Sydney, New South Wales 2006 , Australia
| | - Valentina S A Mella
- School of Life and Environmental Sciences, University of Sydney , Sydney, New South Wales 2006 , Australia
- Sydney School of Veterinary Science, University of Sydney , Sydney, New South Wales 2006 , Australia
| | - Mark B Krockenberger
- Sydney School of Veterinary Science, University of Sydney , Sydney, New South Wales 2006 , Australia
- The Westmead Institute for Medical Research , 176 Hawkesbury Road, Westmead, New South Wales 2145 , Australia
- Marie Bashir Institute for Emerging Infectious diseases and Biosecurity, University of Sydney , 176 Hawkesbury Road, Westmead, New South Wales 2145 , Australia
| | - Jasmine Lindsay
- School of Life and Environmental Sciences, University of Sydney , Sydney, New South Wales 2006 , Australia
| | - Ben D Moore
- Hawkesbury Institute for the Environment, Western Sydney University , Richmond, New South Wales 2753 , Australia
| | - Clare McArthur
- School of Life and Environmental Sciences, University of Sydney , Sydney, New South Wales 2006 , Australia
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Kaczensky P, Salemgareyev A, Linnell JDC, Zuther S, Walzer C, Huber N, Petit T. Post-release Movement Behaviour and Survival of Kulan Reintroduced to the Steppes and Deserts of Central Kazakhstan. FRONTIERS IN CONSERVATION SCIENCE 2021. [DOI: 10.3389/fcosc.2021.703358] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Asiatic wild ass, or kulan (Equus hemionus kulan) were once a key species of the Eurasian steppes and deserts. In Kazakhstan they went extinct by the 1930s. Early reintroductions have reestablished the species in two protected areas, but the species has reclaimed <1% of their former range and remained absent from central Kazakhstan. To initiate restoration in this vast region, we captured and transported a first group of nine wild kulan to a large pre-release enclosure in the Torgai region in 2017, and two more in 2019. We used direct observations and post-release movement data of four kulan equipped with GPS-Iridium collars to document their adaptation process in a vast novel habitat without conspecifics. For comparison with movements in the source populations, we additionally equipped two kulan in Altyn Emel National Park and six in Barsa Kelmes State Nature Reserve. The nine transported kulan formed a cohesive group with very high movement correlation in the enclosure. After release, the group initially stayed tightly together but started to break up by mid-May and all kulan travelled independently by mid-August. With 48,680–136,953 km2, the 95% Autocorrelated Kernel Density Estimation ranges of the reintroduced kulan were huge and about 10–100 times larger than those in the source populations. The reintroduced mares never reconnected, there was no evidence of successful reproduction, and two of the four collared mares were killed by poachers and one died of natural causes. At least one stallion survived in the wild, but the fate of the other uncollared animals remains unclear. We speculate that the fission-fusion dynamics and low movement correlation of kulan societies and the need for migratory movements harbours the risk that animals released into a novel environment loose contact with each other. This risk is likely enhanced in steppe habitats where movement constraining factors are absent. Further kulan reintroductions to the steppes and deserts of central Kazakhstan should aim to release larger groups and build up the free-ranging population quickly to reach a critical mass, increasing the chance of kulan encountering conspecifics to successfully breed and increase their chances of survival.
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Integrating spatial analysis and questionnaire survey to better understand human-onager conflict in Southern Iran. Sci Rep 2021; 11:12423. [PMID: 34127741 PMCID: PMC8203636 DOI: 10.1038/s41598-021-91921-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 06/02/2021] [Indexed: 12/02/2022] Open
Abstract
Southern Iran is a conservation priority area for the endangered Persian onager (Equus hemionus onager), which is threatened by habitat fragmentation and conflict with local communities. To better understand factors that influence onager conservation, we administered a questionnaire in local communities to survey their ecological knowledge, personal experience related to onager, and attitudes toward traditional solutions for reducing crop damage by onager. In addition, we used resistant kernel and factorial least-cost path analyses to identify core areas and corridors for onager movement, and spatial randomization of vehicle collisions and crossing locations to test the predictive ability of resistant kernel and factorial least-cost path predictions of movement. We found that local communities that were knowledgeable about onagers experienced less crop damage from onager compared with those who used traditional methods. Habitat connectivity models revealed that core areas of movement are highly concentrated at the center of protected areas. Some sections of core areas have been cut off by roads where most vehicle collisions with onagers occurred. We propose that effective onager conservation will require integrated landscape-level management to reduce mortality risk, protection of core areas and corridors, development of mitigation strategies to reduce vehicle collisions, and conflict mediation between local communities and onagers.
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Siciliano-Martina L, Light JE, Lawing AM. Cranial morphology of captive mammals: a meta-analysis. Front Zool 2021; 18:4. [PMID: 33485360 PMCID: PMC7825229 DOI: 10.1186/s12983-021-00386-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 01/14/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Captive facilities such as zoos are uniquely instrumental in conservation efforts. To fulfill their potential as bastions for conservation, zoos must preserve captive populations as appropriate proxies for their wild conspecifics; doing so will help to promote successful reintroduction efforts. Morphological changes within captive populations may be detrimental to the fitness of individual animals because these changes can influence functionality; thus, it is imperative to understand the breadth and depth of morphological changes occurring in captive populations. Here, we conduct a meta-analysis of scientific literature reporting comparisons of cranial measures between captive and wild populations of mammals. We investigate the pervasiveness of cranial differences and whether cranial morphological changes are associated with ecological covariates specific to individual species, such as trophic level, dietary breadth, and home range size. RESULTS Cranial measures of skull length, skull width, and the ratio of skull length-to-width differed significantly between many captive and wild populations of mammals reported in the literature. Roughly half of captive populations differed from wild populations in at least one cranial measure, although the degree of changes varied. Carnivorous species with a limited dietary breadth displayed the most consistent changes associated with skull widening. Species with a more generalized diet displayed less morphological changes in captivity. CONCLUSIONS Wild and captive populations of mammals differed in cranial morphology, but the nature and magnitude of their cranial differences varied considerably across taxa. Although changes in cranial morphology occur in captivity, specific changes cannot be generalized for all captive mammal populations. The nature of cranial changes in captivity may be specific to particular taxonomic groups; thus, it may be possible to establish expectations across smaller taxonomic units, or even disparate groups that utilize their cranial morphology in a similar way. Given that morphological changes occurring in captive environments like zoos have the potential to limit reintroduction success, our results call for a critical evaluation of current captive husbandry practices to prevent unnecessary morphological changes.
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Affiliation(s)
- Leila Siciliano-Martina
- Interdisciplinary Program in Ecology & Evolutionary Biology, Texas A&M University, College Station, TX, 77843, USA.
- Department of Biology, Texas State University, San Marcos, TX, 78666, USA.
| | - Jessica E Light
- Interdisciplinary Program in Ecology & Evolutionary Biology, Texas A&M University, College Station, TX, 77843, USA
- Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, 77843, USA
| | - A Michelle Lawing
- Interdisciplinary Program in Ecology & Evolutionary Biology, Texas A&M University, College Station, TX, 77843, USA
- Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, 77843, USA
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Kroesen LP, Hik DS, Cherry SG. Patterns of decadal, seasonal and daily visitation to mineral licks, a critical resource hotspot for mountain goats Oreamnos americanus in the Rocky Mountains. WILDLIFE BIOLOGY 2020. [DOI: 10.2981/wlb.00736] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Laura P. Kroesen
- L. P. Kroesen (https://orcid.org/0000-0002-5524-0664) ✉ and D. S. Hik (https://orcid.org/0000-0002-8994-9305), Biological Sciences, Simon Fraser Univ., Vancouver, BC, Canada
| | - David S. Hik
- L. P. Kroesen (https://orcid.org/0000-0002-5524-0664) ✉ and D. S. Hik (https://orcid.org/0000-0002-8994-9305), Biological Sciences, Simon Fraser Univ., Vancouver, BC, Canada
| | - Seth G. Cherry
- S. G. Cherry (https://orcid.org/0000-0003-4242-3629), Parks Canada Agency, Radium Hot Springs, BC, Canada
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Hennig JD, Scasta JD, Beck JL, Schoenecker KA, King SRB. Systematic review of equids and telemetry collars: implications for deployment and reporting. WILDLIFE RESEARCH 2020. [DOI: 10.1071/wr19229] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Abstract
Data from animals equipped with global positioning system collars have advanced our understanding of vertebrates, but this technology has rarely been employed to study feral equids. Hesitation to equip feral equids with telemetry collars in the USA can often be attributed to safety concerns stemming from one study from the 1980s, where injuries were sustained by feral horses (Equus ferus caballus) equipped with radio-collars. Improvements in collar design over the ensuing quarter-century may have decreased risk of collar-related complications; however, telemetry-based studies on feral equids continue to be limited. In the present review, studies from wild and feral equids worldwide were systematically reviewed to better understand the mortality and injury risk in application of telemetry collars to equids. Our goals were to: (1) report the number of individual equids fitted with telemetry collars (1979–2017); and (2) document the number of individual equids that reportedly died or suffered injuries from collars or other sources. A comparative review of elk (Cervus canadensis), mule deer (Odocoileus hemionus) and pronghorn (Antilocapra americana) was also conducted to evaluate the relative risk of collar-related complications among equids and routinely collared North American ungulates. In total, 1089 wild and feral telemetered equids were identified across 48 studies. Of these, 87 (8.0%) were reported to have died, with only one (0.09%) mortality attributable to a collar. Comparatively, 23.0% (1095) of 4761 elk, mule deer and pronghorn fitted with telemetry collars were found to have died in the same number of studies, though no mortalities were reported to be related to the collar. Although wild and feral equids did not experience increased natural mortality compared with the other ungulates, studies have not provided sufficient information to assess relative risk of collar-related complications. Explicit reporting and discussion of telemetry collar impacts in future publications of all animal species are recommended, especially equids, to improve understanding of how telemetry collars can affect study individuals.
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Nandintsetseg D, Bracis C, Leimgruber P, Kaczensky P, Buuveibaatar B, Lkhagvasuren B, Chimeddorj B, Enkhtuvshin S, Horning N, Ito TY, Olson K, Payne J, Walzer C, Shinoda M, Stabach J, Songer M, Mueller T. Variability in nomadism: environmental gradients modulate the movement behaviors of dryland ungulates. Ecosphere 2019. [DOI: 10.1002/ecs2.2924] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Dejid Nandintsetseg
- Senckenberg Biodiversity and Climate Research Centre Senckenberg Gesellschaft für Naturforschung 60325 Frankfurt (Main) Germany
- Department of Biological Sciences Goethe University Frankfurt 60438 Frankfurt (Main) Germany
- Smithsonian Conservation Biology Institute, National Zoological Park Front Royal Virginia 22630 USA
| | - Chloe Bracis
- Senckenberg Biodiversity and Climate Research Centre Senckenberg Gesellschaft für Naturforschung 60325 Frankfurt (Main) Germany
- Department of Biological Sciences Goethe University Frankfurt 60438 Frankfurt (Main) Germany
- Ifremer, Channel and North Sea Fisheries Research Unit Boulogne‐sur‐Mer France
| | - Peter Leimgruber
- Smithsonian Conservation Biology Institute, National Zoological Park Front Royal Virginia 22630 USA
| | - Petra Kaczensky
- Norwegian Institute for Nature Research NO‐7485 Trondheim Norway
- Research Institute of Wildlife Ecology University of Veterinary Medicine, Vienna ViennaA‐1160Austria
| | | | - Badamjav Lkhagvasuren
- Institute of General and Experimental Biology Mongolian Academy of Sciences Ulaanbaatar 13330 Mongolia
| | | | | | - Ned Horning
- American Museum of Natural History's Center for Biodiversity and Conservation New York New York USA
| | - Takehiko Y. Ito
- Arid Land Research Center Tottori University Tottori 680‐0001 Japan
- Organization for the Strategic Coordination of Research and Intellectual Properties Meiji University Tokyo 168‐8558 Japan
| | - Kirk Olson
- Mongolia Program Wildlife Conservation Society Ulaanbaatar Mongolia
| | - John Payne
- Mongolia Program Wildlife Conservation Society Ulaanbaatar Mongolia
| | - Chris Walzer
- Research Institute of Wildlife Ecology University of Veterinary Medicine, Vienna ViennaA‐1160Austria
- Mongolia Program Wildlife Conservation Society Ulaanbaatar Mongolia
| | - Masato Shinoda
- Graduate School of Environmental Studies Nagoya University Nagoya 464‐8601 Japan
| | - Jared Stabach
- Smithsonian Conservation Biology Institute, National Zoological Park Front Royal Virginia 22630 USA
| | - Melissa Songer
- Smithsonian Conservation Biology Institute, National Zoological Park Front Royal Virginia 22630 USA
| | - Thomas Mueller
- Senckenberg Biodiversity and Climate Research Centre Senckenberg Gesellschaft für Naturforschung 60325 Frankfurt (Main) Germany
- Department of Biological Sciences Goethe University Frankfurt 60438 Frankfurt (Main) Germany
- Smithsonian Conservation Biology Institute, National Zoological Park Front Royal Virginia 22630 USA
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Thaker M, Gupte PR, Prins HHT, Slotow R, Vanak AT. Fine-Scale Tracking of Ambient Temperature and Movement Reveals Shuttling Behavior of Elephants to Water. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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10
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Greenbaum G, Renan S, Templeton AR, Bouskila A, Saltz D, Rubenstein DI, Bar-David S. Revealing life-history traits by contrasting genetic estimations with predictions of effective population size. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2018; 32:817-827. [PMID: 29270998 PMCID: PMC7208180 DOI: 10.1111/cobi.13068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 12/01/2017] [Accepted: 12/08/2017] [Indexed: 06/07/2023]
Abstract
Effective population size, a central concept in conservation biology, is now routinely estimated from genetic surveys and can also be theoretically predicted from demographic, life-history, and mating-system data. By evaluating the consistency of theoretical predictions with empirically estimated effective size, insights can be gained regarding life-history characteristics and the relative impact of different life-history traits on genetic drift. These insights can be used to design and inform management strategies aimed at increasing effective population size. We demonstrated this approach by addressing the conservation of a reintroduced population of Asiatic wild ass (Equus hemionus). We estimated the variance effective size (Nev ) from genetic data (N ev =24.3) and formulated predictions for the impacts on Nev of demography, polygyny, female variance in lifetime reproductive success (RS), and heritability of female RS. By contrasting the genetic estimation with theoretical predictions, we found that polygyny was the strongest factor affecting genetic drift because only when accounting for polygyny were predictions consistent with the genetically measured Nev . The comparison of effective-size estimation and predictions indicated that 10.6% of the males mated per generation when heritability of female RS was unaccounted for (polygyny responsible for 81% decrease in Nev ) and 19.5% mated when female RS was accounted for (polygyny responsible for 67% decrease in Nev ). Heritability of female RS also affected Nev ; hf2=0.91 (heritability responsible for 41% decrease in Nev ). The low effective size is of concern, and we suggest that management actions focus on factors identified as strongly affecting Nev, namely, increasing the availability of artificial water sources to increase number of dominant males contributing to the gene pool. This approach, evaluating life-history hypotheses in light of their impact on effective population size, and contrasting predictions with genetic measurements, is a general, applicable strategy that can be used to inform conservation practice.
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Affiliation(s)
- Gili Greenbaum
- Department of Solar Energy and Environmental Physics, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel
| | - Sharon Renan
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel
| | - Alan R. Templeton
- Department of Biology, Washington University, St. Louis, MO 63130, U.S.A
- Department of Evolutionary and Environmental Ecology, University of Haifa, Haifa 31905, Israel
| | - Amos Bouskila
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - David Saltz
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel
| | - Daniel I. Rubenstein
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, U.S.A
| | - Shirli Bar-David
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel
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Schlägel UE, Merrill EH, Lewis MA. Territory surveillance and prey management: Wolves keep track of space and time. Ecol Evol 2017; 7:8388-8405. [PMID: 29075457 PMCID: PMC5648667 DOI: 10.1002/ece3.3176] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 04/22/2017] [Accepted: 04/24/2017] [Indexed: 12/02/2022] Open
Abstract
Identifying behavioral mechanisms that underlie observed movement patterns is difficult when animals employ sophisticated cognitive‐based strategies. Such strategies may arise when timing of return visits is important, for instance to allow for resource renewal or territorial patrolling. We fitted spatially explicit random‐walk models to GPS movement data of six wolves (Canis lupus; Linnaeus, 1758) from Alberta, Canada to investigate the importance of the following: (1) territorial surveillance likely related to renewal of scent marks along territorial edges, to reduce intraspecific risk among packs, and (2) delay in return to recently hunted areas, which may be related to anti‐predator responses of prey under varying prey densities. The movement models incorporated the spatiotemporal variable “time since last visit,” which acts as a wolf's memory index of its travel history and is integrated into the movement decision along with its position in relation to territory boundaries and information on local prey densities. We used a model selection framework to test hypotheses about the combined importance of these variables in wolf movement strategies. Time‐dependent movement for territory surveillance was supported by all wolf movement tracks. Wolves generally avoided territory edges, but this avoidance was reduced as time since last visit increased. Time‐dependent prey management was weak except in one wolf. This wolf selected locations with longer time since last visit and lower prey density, which led to a longer delay in revisiting high prey density sites. Our study shows that we can use spatially explicit random walks to identify behavioral strategies that merge environmental information and explicit spatiotemporal information on past movements (i.e., “when” and “where”) to make movement decisions. The approach allows us to better understand cognition‐based movement in relation to dynamic environments and resources.
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Affiliation(s)
- Ulrike E Schlägel
- Department of Mathematical and Statistical Sciences University of Alberta Edmonton AB Canada.,Plant Ecology and Nature Conservation Institute of Biochemistry and Biology University of Potsdam Potsdam Germany
| | - Evelyn H Merrill
- Department of Biological Sciences University of Alberta Edmonton AB Canada
| | - Mark A Lewis
- Department of Mathematical and Statistical Sciences University of Alberta Edmonton AB Canada.,Department of Biological Sciences University of Alberta Edmonton AB Canada
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