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Dental and temporomandibular joint pathology of the Arctic fox (Vulpeslagopus). J Comp Pathol 2023; 201:87-99. [PMID: 36753942 DOI: 10.1016/j.jcpa.2023.01.004] [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: 10/16/2022] [Revised: 12/01/2022] [Accepted: 01/08/2023] [Indexed: 02/10/2023]
Abstract
Museum skull specimens from 224 Arctic foxes (Vulpes lagopus) were examined macroscopically using an established protocol for examination of mammalian skull specimens. Foxes were collected from coastal and island regions of Alaska, USA, except for two individuals. Collection years ranged from 1931 to 2016 with most specimens collected during the 1950s and 1960s. The study population comprised more females (n = 134, 59.8%) than males (n = 83, 37.0%) and individuals of unknown sex (n = 7, 3.1%). There were 108 (48.2%) young adults, 115 (51.3%) adults, and one (0.4%) individual of unknown age. A total of 8,891 teeth (94.5%) were available for examination. The most common types of pathology observed were periodontitis (n = 222, 99.1%), dental fractures (n = 175, 78.1%) and attrition/abrasion (n = 198, 88.4%). Periapical lesions (n = 12, 5.3%), temporomandibular joint (TMJ) osteoarthritis (n = 3, 1.3%) and root number variation (n = 5, 2.2%) were less common. Enamel hypoplasia was noted in eight foxes (3.6%), all of which were discovered on St. Matthew Island, Alaska, in 1963. As in other canid species, periodontitis, attrition/abrasion and tooth fractures are common in the Arctic fox, while TMJ pathology is rare. Loss of tooth crown substance probably reflects the influence of diet, interspecific and conspecific aggression and oral trauma due to trapping and hunting methods. The high prevalence of periodontitis is probably also due to the combined effects of diet, genetics and host immune reaction to oral bacteria.
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Factors that affect migratory Western Atlantic red knots (Calidris canutus rufa) and their prey during spring staging on Virginia’s barrier islands. PLoS One 2022; 17:e0270224. [PMID: 35776754 PMCID: PMC9249208 DOI: 10.1371/journal.pone.0270224] [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: 08/17/2021] [Accepted: 06/06/2022] [Indexed: 11/19/2022] Open
Abstract
Understanding factors that influence a species’ distribution and abundance across the annual cycle is required for range-wide conservation. Thousands of imperiled red knots (Calidris cantus rufa) stop on Virginia’s barrier islands each year to replenish fat during spring migration. We investigated the variation in red knot presence and flock size, the effects of prey on this variation, and factors influencing prey abundance on Virginia’s barrier islands. We counted red knots and collected potential prey samples at randomly selected sites from 2007–2018 during a two-week period during early and peak migration. Core samples contained crustaceans (Orders Amphipoda and Calanoida), blue mussels (Mytilus edulis), coquina clams (Donax variabilis), and miscellaneous prey (horseshoe crab eggs (Limulus polyphemus), angel wing clams (Cyrtopleura costata), and other organisms (e.g., insect larvae, snails, worms)). Estimated red knot peak counts in Virginia during 21–27 May were highest in 2012 (11,959) and lowest in 2014 (2,857; 12-year peak migration x¯ = 7,175, SD = 2,869). Red knot and prey numbers varied across sampling periods and substrates (i.e., peat and sand). Red knots generally used sites with more prey. Miscellaneous prey ( x¯ = 2401.00/m2, SE = 169.16) influenced red knot presence at a site early in migration, when we only sampled on peat banks. Coquina clams ( x¯ = 1383.54/m2, SE = 125.32) and blue mussels ( x¯ = 777.91/m2, SE = 259.31) affected red knot presence at a site during peak migration, when we sampled both substrates. Few relationships between prey and red knot flock size existed, suggesting that other unmeasured factors determined red knot numbers at occupied sites. Tide and mean daily water temperature affected prey abundance. Maximizing the diversity, availability, and abundance of prey for red knots on barrier islands requires management that encourages the presence of both sand and peat bank intertidal habitats.
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Lotsander A, Hasselgren M, Larm M, Wallén J, Angerbjörn A, Norén K. Low Persistence of Genetic Rescue Across Generations in the Arctic Fox (Vulpes lagopus). J Hered 2021; 112:276-285. [PMID: 33738472 PMCID: PMC8141685 DOI: 10.1093/jhered/esab011] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/17/2021] [Indexed: 12/11/2022] Open
Abstract
Genetic rescue can facilitate the recovery of small and isolated populations suffering from inbreeding depression. Long-term effects are however complex, and examples spanning over multiple generations under natural conditions are scarce. The aim of this study was to test for long-term effects of natural genetic rescue in a small population of Scandinavian Arctic foxes (Vulpes lagopus). By combining a genetically verified pedigree covering almost 20 years with a long-term dataset on individual fitness (n = 837 individuals), we found no evidence for elevated fitness in immigrant F2 and F3 compared to native inbred foxes. Population inbreeding levels showed a fluctuating increasing trend and emergence of inbreeding within immigrant lineages shortly after immigration. Between 0–5 and 6–9 years post immigration, the average number of breeding adults decreased by almost 22% and the average proportion of immigrant ancestry rose from 14% to 27%. Y chromosome analysis revealed that 2 out of 3 native male lineages were lost from the gene pool, but all founders represented at the time of immigration were still contributing to the population at the end of the study period through female descendants. The results highlight the complexity of genetic rescue and suggest that beneficial effects can be brief. Continuous gene flow may be needed for small and threatened populations to recover and persist in a longer time perspective.
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Affiliation(s)
- Anna Lotsander
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | | | - Malin Larm
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Johan Wallén
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | | | - Karin Norén
- Department of Zoology, Stockholm University, Stockholm, Sweden
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Andreassen HP, Sundell J, Ecke F, Halle S, Haapakoski M, Henttonen H, Huitu O, Jacob J, Johnsen K, Koskela E, Luque-Larena JJ, Lecomte N, Leirs H, Mariën J, Neby M, Rätti O, Sievert T, Singleton GR, van Cann J, Vanden Broecke B, Ylönen H. Population cycles and outbreaks of small rodents: ten essential questions we still need to solve. Oecologia 2021; 195:601-622. [PMID: 33369695 PMCID: PMC7940343 DOI: 10.1007/s00442-020-04810-w] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 11/19/2020] [Indexed: 12/25/2022]
Abstract
Most small rodent populations in the world have fascinating population dynamics. In the northern hemisphere, voles and lemmings tend to show population cycles with regular fluctuations in numbers. In the southern hemisphere, small rodents tend to have large amplitude outbreaks with less regular intervals. In the light of vast research and debate over almost a century, we here discuss the driving forces of these different rodent population dynamics. We highlight ten questions directly related to the various characteristics of relevant populations and ecosystems that still need to be answered. This overview is not intended as a complete list of questions but rather focuses on the most important issues that are essential for understanding the generality of small rodent population dynamics.
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Affiliation(s)
- Harry P Andreassen
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway
| | - Janne Sundell
- Lammi Biological Station, University of Helsinki, Pääjärventie 320, 16900, Lammi, Finland
| | - Fraucke Ecke
- Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd, 90183, Umeå, Sweden
| | - Stefan Halle
- Institute of Ecology and Evolution, Friedrich Schiller University Jena, Dornburger Str. 159, 07743, Jena, Germany
| | - Marko Haapakoski
- Department of Biological and Environmental Science, Konnevesi Research Station, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Heikki Henttonen
- Terrestrial Population Dynamics, Natural Resources Institute Finland, Latokartanonkaari 9, 00790, Helsinki, Finland
| | - Otso Huitu
- Terrestrial Population Dynamics, Natural Resources Institute Finland, Latokartanonkaari 9, 00790, Helsinki, Finland
| | - Jens Jacob
- Federal Research Centre for Cultivated Plants, Vertebrate Research, Julius Kühn-Institut, Toppheideweg 88, 48161, Münster, Germany
| | - Kaja Johnsen
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway
| | - Esa Koskela
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Juan Jose Luque-Larena
- Departamento de Ciencias Agroforestales, Escuela Tecnica Superior de Ingenierıas Agrarias, Universidad de Valladolid, Campus La Yutera, Avenida de Madrid 44, 34004, Palencia, Spain
| | - Nicolas Lecomte
- Canada Research Chair in Polar and Boreal Ecology and Centre D'Études Nordiques, Department of Biology, Université de Moncton, 18 Avenue Antonine-Maillet, Moncton, NB, E1A 3E9, Canada
| | - Herwig Leirs
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Universiteitslain 1, 2610, Wilrijk, Belgium
| | - Joachim Mariën
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Universiteitslain 1, 2610, Wilrijk, Belgium
| | - Magne Neby
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway
| | - Osmo Rätti
- Arctic Centre, University of Lapland, P.O. Box 122, 96101, Rovaniemi, Finland
| | - Thorbjörn Sievert
- Department of Biological and Environmental Science, Konnevesi Research Station, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Grant R Singleton
- International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines
- Natural Resources Institute, University of Greenwich, Chatham Marine, Kent, ME4 4TB, UK
| | - Joannes van Cann
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Bram Vanden Broecke
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Universiteitslain 1, 2610, Wilrijk, Belgium
| | - Hannu Ylönen
- Department of Biological and Environmental Science, Konnevesi Research Station, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland.
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Thierry A, De Bouillane De Lacoste N, Ulvund K, Andersen R, MeÅs R, Eide NE, Landa A. Use of Supplementary Feeding Dispensers by Arctic Foxes in Norway. J Wildl Manage 2020. [DOI: 10.1002/jwmg.21831] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Anne‐Mathilde Thierry
- Norsk institutt for naturforskning (NINA) P.O. Box 5685, Torgard, NO‐7485 Trondheim Norway
| | | | | | - Roy Andersen
- NINA P.O. Box 5685, Torgard, NO‐7485 Trondheim Norway
| | - Roger MeÅs
- NINA P.O. Box 5685, Torgard, NO‐7485 Trondheim Norway
| | - Nina E. Eide
- NINA P.O. Box 5685, Torgard, NO‐7485 Trondheim Norway
| | - Arild Landa
- NINA Thormøhlens gate 55, NO‐5006 Bergen Norway
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Bobretsov AV, Lukyanova LE, Bykhovets NM, Petrov AN. Impact of climate change on population dynamics of forest voles (Myodes) in northern Pre-Urals: The role of landscape effects. CONTEMP PROBL ECOL+ 2017. [DOI: 10.1134/s1995425517030039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Frisman E, Neverova G, Kulakov M. Change of dynamic regimes in the population of species with short life cycles: Results of an analytical and numerical study. ECOLOGICAL COMPLEXITY 2016. [DOI: 10.1016/j.ecocom.2016.02.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Fuchs B, Zimmermann B, Wabakken P, Bornstein S, Månsson J, Evans AL, Liberg O, Sand H, Kindberg J, Ågren EO, Arnemo JM. Sarcoptic mange in the Scandinavian wolf Canis lupus population. BMC Vet Res 2016; 12:156. [PMID: 27459965 PMCID: PMC4962404 DOI: 10.1186/s12917-016-0780-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 07/20/2016] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Sarcoptic mange, a parasitic disease caused by the mite Sarcoptes scabiei, is regularly reported on wolves Canis lupus in Scandinavia. We describe the distribution and transmission of this parasite within the small but recovering wolf population by analysing 269 necropsy reports and performing a serological survey on 198 serum samples collected from free-ranging wolves between 1998 and 2013. RESULTS The serological survey among 145 individual captured Scandinavian wolves (53 recaptures) shows a consistent presence of antibodies against sarcoptic mange. Seropositivity among all captured wolves was 10.1 % (CI. 6.4 %-15.1 %). Sarcoptic mange-related mortality reported at necropsy was 5.6 % and due to secondary causes, predominantly starvation. In the southern range of the population, seroprevalence was higher, consistent with higher red fox densities. Female wolves had a lower probability of being seropositive than males, but for both sexes the probability increased with pack size. Recaptured individuals changing from seropositive to seronegative suggest recovery from sarcoptic mange. The lack of seropositive pups (8-10 months, N = 56) and the occurrence of seropositive and seronegative individuals in the same pack indicates interspecific transmission of S. scabiei into this wolf population. CONCLUSIONS We consider sarcoptic mange to have little effect on the recovery of the Scandinavian wolf population. Heterogenic infection patterns on the pack level in combination with the importance of individual-based factors (sex, pack size) and the north-south gradient for seroprevalence suggests low probability of wolf-to-wolf transmission of S. scabiei in Scandinavia.
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Affiliation(s)
- Boris Fuchs
- Faculty of Applied Ecology and Agricultural Sciences, Hedmark University College, Campus Evenstad, N-2480 Koppang, Norway
| | - Barbara Zimmermann
- Faculty of Applied Ecology and Agricultural Sciences, Hedmark University College, Campus Evenstad, N-2480 Koppang, Norway
| | - Petter Wabakken
- Faculty of Applied Ecology and Agricultural Sciences, Hedmark University College, Campus Evenstad, N-2480 Koppang, Norway
| | - Set Bornstein
- Department of Virology, Immunobiology and Parasitology, National Veterinary Institute, SE-75189 Uppsala, Sweden
| | - Johan Månsson
- Department of Ecology, Grimsö Wildlife Research Station, Swedish University of Agricultural Sciences, SE-73091 Riddarhyttan, Sweden
| | - Alina L. Evans
- Faculty of Applied Ecology and Agricultural Sciences, Hedmark University College, Campus Evenstad, N-2480 Koppang, Norway
| | - Olof Liberg
- Department of Ecology, Grimsö Wildlife Research Station, Swedish University of Agricultural Sciences, SE-73091 Riddarhyttan, Sweden
| | - Håkan Sand
- Department of Ecology, Grimsö Wildlife Research Station, Swedish University of Agricultural Sciences, SE-73091 Riddarhyttan, Sweden
| | - Jonas Kindberg
- Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, SE-90183 Umeå, Sweden
| | - Erik O. Ågren
- Department of Pathology and Wildlife Disease, National Veterinary Institute, SE-75189 Uppsala, Sweden
| | - Jon M. Arnemo
- Faculty of Applied Ecology and Agricultural Sciences, Hedmark University College, Campus Evenstad, N-2480 Koppang, Norway
- Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, SE-90183 Umeå, Sweden
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10
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Ehrich D, Ims RA, Yoccoz NG, Lecomte N, Killengreen ST, Fuglei E, Rodnikova AY, Ebbinge BS, Menyushina IE, Nolet BA, Pokrovsky IG, Popov IY, Schmidt NM, Sokolov AA, Sokolova NA, Sokolov VA. What Can Stable Isotope Analysis of Top Predator Tissues Contribute to Monitoring of Tundra Ecosystems? Ecosystems 2015. [DOI: 10.1007/s10021-014-9834-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Elmhagen B, Kindberg J, Hellström P, Angerbjörn A. A boreal invasion in response to climate change? Range shifts and community effects in the borderland between forest and tundra. AMBIO 2015; 44 Suppl 1:S39-50. [PMID: 25576279 PMCID: PMC4289007 DOI: 10.1007/s13280-014-0606-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
It has been hypothesized that climate warming will allow southern species to advance north and invade northern ecosystems. We review the changes in the Swedish mammal and bird community in boreal forest and alpine tundra since the nineteenth century, as well as suggested drivers of change. Observed changes include (1) range expansion and increased abundance in southern birds, ungulates, and carnivores; (2) range contraction and decline in northern birds and carnivores; and (3) abundance decline or periodically disrupted dynamics in cyclic populations of small and medium-sized mammals and birds. The first warm spell, 1930-1960, stands out as a period of substantial faunal change. However, in addition to climate warming, suggested drivers of change include land use and other anthropogenic factors. We hypothesize all these drivers interacted, primarily favoring southern generalists. Future research should aim to distinguish between effects of climate and land-use change in boreal and tundra ecosystems.
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Affiliation(s)
- Bodil Elmhagen
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden
| | - Jonas Kindberg
- Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden
- Swedish Association for Hunting and Wildlife Management, Öster-Malma, 611 91 Nyköping, Sweden
| | - Peter Hellström
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden
| | - Anders Angerbjörn
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden
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The relationship between wolverine and larger predators, lynx and wolf, in a historical ecosystem context. Oecologia 2014; 175:625-37. [PMID: 24652527 DOI: 10.1007/s00442-014-2918-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 03/05/2014] [Indexed: 10/25/2022]
Abstract
Apex predators play an important role in shaping ecosystem structure. They may suppress smaller predators (mesopredators) but also subsidize scavengers via carrion provisioning. However, the importance of these interactions can change with ecosystem context. The wolverine (Gulo gulo) is a cold-adapted carnivore and facultative scavenger. It has a circumboreal distribution, where it could be either suppressed or subsidized by larger predators. In Scandinavia, the wolverine might interact with two larger predators, wolf (Canis lupus) and lynx (Lynx lynx), but human persecution decimated the populations in the nineteenth and early twentieth century. We investigated potential relationships between wolverine and the larger predators using hunting bag statistics from 15 Norwegian and Swedish counties in 1846-1922. Our best models showed a positive association between wolverine and lynx trends, taking ecological and human factors into account. There was also a positive association between year-to-year fluctuations in wolverine and wolf in the latter part of the study period. We suggest these associations could result from positive lynx-wolverine interactions through carrion provisioning, while wolves might both suppress wolverine and provide carrion with the net effect becoming positive when wolf density drops below a threshold. Wolverines could thus benefit from lynx presence and low-to-intermediate wolf densities.
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White T. Experimental and observational evidence reveals that predators in natural environments do not regulate their prey: They are passengers, not drivers. ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY 2013. [DOI: 10.1016/j.actao.2013.09.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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14
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Elmhagen B, Hersteinsson P, Norén K, Unnsteinsdottir ER, Angerbjörn A. From breeding pairs to fox towns: the social organisation of arctic fox populations with stable and fluctuating availability of food. Polar Biol 2013. [DOI: 10.1007/s00300-013-1416-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Meijer T, Elmhagen B, Eide NE, Angerbjörn A. Life history traits in a cyclic ecosystem: a field experiment on the arctic fox. Oecologia 2013; 173:439-47. [PMID: 23512202 DOI: 10.1007/s00442-013-2641-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 03/04/2013] [Indexed: 10/27/2022]
Abstract
The reproduction of many species depends strongly on variation in food availability. The main prey of the arctic fox in Fennoscandia are cyclic small rodents, and its number of litters and litter size vary depending on the phase of the rodent cycle. In this experiment, we studied if the arctic fox adjusts its reproduction as a direct response to food abundance, in accordance with the food limitation hypothesis, or if there are additional phase-dependent trade-offs that influence its reproduction. We analysed the weaning success, i.e. proportion of arctic fox pairs established during mating that wean a litter in summer, of 422 pairs of which 361 were supplementary winter fed, as well as the weaned litter size of 203 litters of which 115 were supplementary winter fed. Females without supplementary winter food over-produced cubs in relation to food abundance in the small rodent increase phase, i.e. the litter size was equal to that in the peak phase when food was more abundant. The litter size for unfed females was 6.38 in the increase phase, 7.11 in the peak phase and 3.84 in the decrease phase. The litter size for supplementary winter-fed litters was 7.95 in the increase phase, 10.61 in the peak phase and 7.86 in the decrease phase. Thus, feeding had a positive effect on litter size, but it did not diminish the strong impact of the small rodent phase, supporting phase-dependent trade-offs in addition to food determining arctic fox reproduction.
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Affiliation(s)
- Tomas Meijer
- Department of Zoology, Stockholm University, 106 91, Stockholm, Sweden,
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16
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Angerbjörn A, Eide NE, Dalén L, Elmhagen B, Hellström P, Ims RA, Killengreen S, Landa A, Meijer T, Mela M, Niemimaa J, Norén K, Tannerfeldt M, Yoccoz NG, Henttonen H. Carnivore conservation in practice: replicated management actions on a large spatial scale. J Appl Ecol 2013. [DOI: 10.1111/1365-2664.12033] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anders Angerbjörn
- Department of Zoology; Stockholm University; SE-10691; Stockholm; Sweden
| | - Nina E. Eide
- Norwegian Institute for Nature Research; N-7845; Trondheim; Norway
| | - Love Dalén
- Department of Zoology; Stockholm University; SE-10691; Stockholm; Sweden
| | - Bodil Elmhagen
- Department of Zoology; Stockholm University; SE-10691; Stockholm; Sweden
| | - Peter Hellström
- Department of Zoology; Stockholm University; SE-10691; Stockholm; Sweden
| | - Rolf A. Ims
- Department of Arctic and Marine Biology; University of Tromsø; N-9037; Tromsø; Norway
| | - Siw Killengreen
- Department of Arctic and Marine Biology; University of Tromsø; N-9037; Tromsø; Norway
| | - Arild Landa
- Norwegian Institute for Nature Research; N-7845; Trondheim; Norway
| | - Tomas Meijer
- Department of Zoology; Stockholm University; SE-10691; Stockholm; Sweden
| | - Matti Mela
- Metsähallitus-Finnish Park and Forest Service; FI-99801; Ivalo; Finland
| | - Jukka Niemimaa
- Vantaa Research Centre; Finnish Forest Research Institute; Vantaa; Finland
| | - Karin Norén
- Department of Zoology; Stockholm University; SE-10691; Stockholm; Sweden
| | - Magnus Tannerfeldt
- Department of Zoology; Stockholm University; SE-10691; Stockholm; Sweden
| | - Nigel G. Yoccoz
- Department of Arctic and Marine Biology; University of Tromsø; N-9037; Tromsø; Norway
| | - Heikki Henttonen
- Vantaa Research Centre; Finnish Forest Research Institute; Vantaa; Finland
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Fraser J, Karpanty S, Cohen J, Truitt B. The Red Knot (Calidris canutus rufa) decline in the western hemisphere: is there a lemming connection? CAN J ZOOL 2013. [DOI: 10.1139/cjz-2012-0233] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Numbers of Western Atlantic Red Knots (Calidris canutus rufa (A. Wilson, 1813)) have declined since 1980, with a sustained downward trend observed after 1998. Because the reproductive output of a closely related Eurasian subspecies (Calidris canutus islandica (L., 1767)) is known to be low when lemming numbers are low, and because lemming cycles in Fennoscandia were recently interrupted, we investigated the relationship between the rodent cycle in arctic Canada and numbers of C. c. rufa migrating through the United States. Shooting records from Cape Cod in the 1800s and Red Knot counts on the Delaware Bay from 1986 to 1998 cycled with 4-year periods. Annual peaks in numbers of Red Knots stopping in the Delaware Bay in 1986–1998 occurred 2 years after arctic rodent peaks more often than expected at random. The results suggest that the reproductive output of C. c. rufa was linked to the rodent cycle before the Red Knot decline. There is no evidence that such a link existed after 1998. These findings are consistent with the hypothesis that an interruption of the rodent cycle in Red Knot habitat could have been a driver in the recent Red Knot decline. Field studies in the Arctic are needed to further investigate this hypothesis.
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Affiliation(s)
- J.D. Fraser
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
| | - S.M. Karpanty
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
| | - J.B. Cohen
- Department of Environmental and Forest Biology, State University of New York (SUNY), College of Environmental Science and Forestry, Syracuse, NY 13210, USA
| | - B.R. Truitt
- The Nature Conservancy, Virginia Coast Reserve, Nassawadox, VA 23413, USA
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