Documenting lemming population change in the Arctic: Can we detect trends?

Abstract

Lemmings are a key component of tundra food webs and changes in their dynamics can affect the whole ecosystem. We present a comprehensive overview of lemming monitoring and research activities, and assess recent trends in lemming abundance across the circumpolar Arctic. Since 2000, lemmings have been monitored at 49 sites of which 38 are still active. The sites were not evenly distributed with notably Russia and high Arctic Canada underrepresented. Abundance was monitored at all sites, but methods and levels of precision varied greatly. Other important attributes such as health, genetic diversity, and potential drivers of population change, were often not monitored. There was no evidence that lemming populations were decreasing in general, although a negative trend was detected for low arctic populations sympatric with voles. To keep the pace of arctic change, we recommend maintaining long-term programs while harmonizing methods, improving spatial coverage and integrating an ecosystem perspective.

Consequences of a changing environment on the breeding phenology and reproductive success components in a long‐distance migratory bird

“…Alternatively, a change in the predator community could explain the temporal increase in nesting success. However, we have no evidence that the abundance of predator or of their main prey, lemmings, changed over time at our study site (Ehrich et al, 2019;Gauthier et al, 2013).…”

Arctic terrestrial biodiversity status and trends: A synopsis of science supporting the CBMP State of Arctic Terrestrial Biodiversity Report

“…Of these six functional groups, muskoxen (Ovibos moschatus, Cuyler et al 2020) and lemmings (Lemmus spp. and Dicrostonyx spp., Ehrich et al 2020), representing large and small herbivores, respectively, and occupying key positions in tundra food webs, were addressed in this special issue. Assessment of status and trend, associated with the CBMP terrestrial monitoring plan and the forthcoming State of the Arctic Terrestrial Biodiversity Report, but beyond the scope of this paper, is also available for two other taxa of Arctic mammals: wild reindeer/caribou (Rangifer tarandus, https://carma.caff.is/) and Arctic fox (Vulpes lagopus, Berteaux et al 2017).…”

“…Due to the large variability in amplitude and regularity of lemming cycles, trends are inherently difficult to identify. Given that caveat, and the heterogeneity in existing data, as presented in Ehrich et al (2020), available data indicate the following:…”

“…Population size estimates were available for all 55 delineated muskox populations (Cuyler et al 2020). Lemming population dynamics are currently monitored at 38 sites covering all biogeographic subzones and major geographic areas of the Arctic, mostly through a variety of abundance indices (Ehrich et al 2020). For both FECs, it was difficult to assess overall trends because of large heterogeneity in methods and effort, infrequent surveys, and inconsistencies in the data in the case of muskoxen, and important geographic gaps in the case of lemming data.…”

Resource partitioning among avian predators of the Arctic tundra

“…Lemming densities were estimated with spatially explicit capturerecapture analyses with the secr package (Efford, 2020; see details in Fauteux et al, 2015) for each trapping period and grid. We assumed that trapped lemmings were representative of the population of prey available for predators in years when pellets were collected.…”