Population limitation in a non-cyclic arctic fox population in a changing climate

Pálsson, Snæbjörn; Hersteinsson, Páll; Unnsteinsdóttir, Ester Rut; Nielsen, Ólafur K.

doi:10.1007/s00442-015-3536-7

Cited by 18 publications

(51 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, taking these differences into account, there were also similarities in demographic response and especially in the carrying capacity. Pálsson et al (2016) reported changes in many Icelandic bird populations that are included in the Arctic fox diet. So these changes are likely the major component in the carrying capacity for Icelandic Arctic foxes.…”

Section: Coastal and Inland Populationsmentioning

confidence: 96%

“…The hunting statistics of Arctic foxes in Iceland, collected by the Environment Agency of Iceland and its predecessor, the Wildlife Management Institute, suggest that the Arctic fox population in Iceland declined from the late 1950s until the 1970s, whereafter the population has been on the increase. The causes of this fluctuation have been related to changes in prey populations as well as climate, but the hunting effort is considered to have been stable during this period (Pálsson et al 2016). Such factors can directly affect birth and mortality rates and would be of central importance for understanding and managing the Arctic fox population.…”

Section: Electronic Supplementary Materialsmentioning

confidence: 99%

“…In comparison to areas where rodents are the main prey of Arctic foxes, the prey base of the Arctic fox in Iceland, mainly birds of various species, has been relatively stable and predictable from year to year (Hersteinsson 1992; Hersteinsson and Macdonald 1996;Pálsson et al 2016). The Arctic fox population has adapted to this situation by lowered fertility compared to mainland North America and Eurasia, and the population density has probably stayed close to carrying capacity for most of the time since it arrived in the country at the end of the Ice Age (Angerbjörn et al 2004).…”

Section: Electronic Supplementary Materialsmentioning

confidence: 99%

“…An index of changes in population size over time is based on hunting statistics, recorded by the government of Iceland, with hunters required to give a detailed report of the annual catch (Pálsson et al 2016). Full access to the foxhunting data was granted for the purpose of this study, courtesy of the Environment Agency of Iceland and The Icelandic Ministry for the Environment and Natural Resources.…”

Section: Changes In Arctic Fox Population Sizementioning

confidence: 99%

“…During the study period, the population size has fluctuated around the carrying capacity, which has been increasing during the last decade possibly due favourable conditions both in temperature and food resources (Pálsson et al 2016). In years when the size has become larger than the carrying capacity, the population growth has generally been negative.…”

Section: Population Fluctuationsmentioning

confidence: 99%

See 4 more Smart Citations

The fall and rise of the Icelandic Arctic fox (Vulpes lagopus): a 50-year demographic study on a non-cyclic Arctic fox population

et al. 2016

View full text Add to dashboard Cite

In territorial species, observed density dependence is often manifest in lowered reproductive output at high population density where individuals have fewer resources or are forced to inhabit low-quality territories. The Arctic fox (Vulpes lagopus) in Iceland is territorial throughout the year and feeds mostly on birds, since lemmings are absent from the country. Thus, the population does not exhibit short-term population cycles that are evident in most of the species' geographical range. The population has, however, gone through a major long-term fluctuation in population size. Because of the stability in hunting effort and reliable hunting records since 1958, the total number of adult foxes killed annually can be used as an index of population size (N t ). An index of carrying capacity (K) from population growth data for five separate time blocks during 1958-2007 revealed considerable variation in K and allowed a novel definition of population density in terms of K, or N t /K. Correlation analysis suggested that the reproductive rate was largely determined by the proportion of territorial foxes in the population. Variation in litter size and cub mortality was, on the other hand, related to climatic variation. Thus, Arctic foxes in Iceland engage in typical contest competition but can adapt their territory sizes in response to both temporal and spatial variation in carrying capacity, resulting in surprisingly little variation in litter size.

show abstract

Section: Coastal and Inland Populationsmentioning

confidence: 96%

Section: Electronic Supplementary Materialsmentioning

confidence: 99%

Section: Electronic Supplementary Materialsmentioning

confidence: 99%

Section: Changes In Arctic Fox Population Sizementioning

confidence: 99%

Section: Population Fluctuationsmentioning

confidence: 99%

See 3 more Smart Citations

The fall and rise of the Icelandic Arctic fox (Vulpes lagopus): a 50-year demographic study on a non-cyclic Arctic fox population

et al. 2016

View full text Add to dashboard Cite

show abstract

Feast to famine: Sympatric predators respond differently to seasonal prey scarcity on thelow Arctictundra

Rodrigues

Roth

2023

Ecology and Evolution

View full text Add to dashboard Cite

Resource fluctuation is a major driver of animal movement, influencing strategic choices such as residency vs nomadism, or social dynamics. The Arctic tundra is characterized by strong seasonality: Resources are abundant during the short summers but scarce in winters. Therefore, expansion of boreal-forest species onto the tundra raises questions on how they cope with winter-resource scarcity. We examined a recent incursion by red foxes (Vulpes vulpes) onto the coastal tundra of northern Manitoba, an area historically occupied by Arctic foxes (Vulpes lagopus) that lacks access to anthropogenic foods, and compared seasonal shifts in space use of the two species. We used 4 years of telemetry data following 8 red foxes and 11 Arctic foxes to test the hypothesis that the movement tactics of both species are primarily driven by temporal variability of resources. We also predicted that the harsh tundra conditions in winter would drive red foxes to disperse more often and maintain larger home ranges year-round than Arctic foxes, which are adapted to this environment. Dispersal was the most frequent winter movement tactic in both fox species, despite its association with high mortality (winter mortality was 9.4 times higher in dispersers than residents). Red foxes consistently dispersed toward the boreal forest, whereas Arctic foxes primarily used sea ice to disperse. Home range size of red and Arctic foxes did not differ in summer, but resident red foxes substantially increased their home range size in winter, whereas home range size of resident Arctic foxes did not change seasonally. As climate changes, abiotic constraints on some species may relax, but associated declines in prey communities may lead to local extirpation of many predators, notably by favoring dispersal during resource scarcity.

show abstract

Contributions from terrestrial and marine resources stabilize predator populations in a rapidly changing climate

et al. 2021

View full text Add to dashboard Cite

Climate change has different and sometimes divergent effects on terrestrial and marine food webs, and in coastal ecosystems, these effects are tightly interlinked. Responses of opportunistic coastal predators and scavengers to climate change may thus be complex and potentially highly flexible, and can simultaneously serve as indicators of, and have profound impacts on, lower trophic levels. Gaining mechanistic understanding of these responses is therefore important, but often not feasible due to lack of longterm data from marked individuals. Here, we used a Bayesian integrated population model (IPM) to elucidate the effects of arctic warming and concurrent changes in terrestrial and marine resource availability on population dynamics of the opportunistic arctic fox (Vulpes lagopus) in Svalbard. Joint analysis of four types of data (den survey, age-at-harvest, placental scars, mark-recovery) revealed relatively stable population size and age structure over the last 22 yr (1997-2019) despite rapid environmental change linked to climate warming. This was related to the fact that terrestrial resources (reindeer carcasses, geese) became more abundant while the availability of marine resources (seal pups/carrion) decreased, and was driven by divergent trends in different vital rates (e.g., increased pregnancy rate but decreased pup survival). Balanced contributions of survival vs. reproduction and of immigration vs. local demography further stabilized population size. Our study thus sheds light on the mechanisms underlying population dynamics of opportunistic carnivores exploiting terrestrial and marine resources and suggests that exploitation of resources across different ecosystems can buffer predators against climate change. Additionally, it highlights the large potential of IPMs as tools to understand and predict the effects of environmental change on wildlife populations, even when data on marked individuals are sparse.

show abstract

Population limitation in a non-cyclic arctic fox population in a changing climate

Cited by 18 publications

References 39 publications

The fall and rise of the Icelandic Arctic fox (Vulpes lagopus): a 50-year demographic study on a non-cyclic Arctic fox population

The fall and rise of the Icelandic Arctic fox (Vulpes lagopus): a 50-year demographic study on a non-cyclic Arctic fox population

Feast to famine: Sympatric predators respond differently to seasonal prey scarcity on thelow Arctictundra

Contributions from terrestrial and marine resources stabilize predator populations in a rapidly changing climate

Contact Info

Product

Resources

About