Circumpolar status of Arctic ptarmigan: Population dynamics and trends

Abstract

Rock ptarmigan (Lagopus muta) and willow ptarmigan (L. lagopus) are Arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. Here, we compiled information from 90 ptarmigan study sites from 7 Arctic countries, where almost half of the sites are still monitored. Rock ptarmigan showed an overall negative trend on Iceland and Greenland, while Svalbard and Newfoundland had positive trends, and no significant trends in Alaska. For willow ptarmigan, there was a negative trend in mid-Sweden and eastern Russia, while northern Fennoscandia, North America and Newfoundland had no significant trends. Both species displayed some periods with population cycles (short 3-6 years and long 9-12 years), but cyclicity changed through time for both species. We propose that simple, cost-efficient systematic surveys that capture the main feature of ptarmigan population dynamics can form the basis for citizen science efforts in order to fill knowledge gaps for the many regions that lack systematic ptarmigan monitoring programs.

Survival and Migration of Rock Ptarmigan in Central Scandinavia

“…Because our study only lasted two years, we are not able to estimate robustly any between year variation due to stochastic environmental factors or variation in harvest pressure. In addition, recent studies of rock ptarmigan throughout their range has shown that cyclic dynamics is a common feature (Fuglei et al, 2019), suggesting that also demographic rates are likely to fluctuate temporarily. Often, populations inhabiting alpine areas (i.e., high altitudes) have higher survival and lower reproduction compared to populations/species at lower elevations (Sandercock et al, 2005a,b).…”

“…In general, alpine populations should be expected to move upward, whereas polar tundra species are expected to conduct latitudinal movements (Lehikoinen et al, 2019). Among the few resident birds in these habitats, the rock ptarmigan (Lagopus muta) has a wide, circumpolar distribution across the northern tundra and high-mountain regions (Storch, 2007;Fuglei et al, 2019). Rock ptarmigan as a species is expected to be strongly affected by climate change (Booms et al, 2012;Revermann et al, 2012;Hansen et al, 2013), and is therefore a suitable model species for examining climate change effects on alpine wildlife populations.…”

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

“…In this issue, circumpolar terrestrial bird FEC-attribute trends and monitoring coverage are discussed in three papers: Fuglei et al (2020) focused on the Arctic-resident herbivores, rock ptarmigans (Lagopus muta), and willow ptarmigans (Lagopus lagopus); Franke et al 2020focused on top predators, the Arctic-resident gyrfalcon (Falco rusticolus), and the migrant peregrine falcon (Falco peregrinus); and Smith et al (2020) reviewed the status of all main terrestrial bird populations (88 species included) according to functional groups (herbivore, insectivore, etc. ), and 'flyways' (main migration routes) utilized by different populations.…”

“…Birds: Biodiversity status Fuglei et al (2020) compiled the first circumpolar synthesis of ptarmigan trends and added considerable broad-scale understanding of ptarmigan population dynamics. For rock ptarmigan, there was a significant, declining trend in density in 10 of 31 monitoring sites (time series), while a significant increase in density was found at five sites.…”

“…Ptarmigan populations have been monitored at over 90 sites, with about half of them still being monitored (Fuglei et al 2020). Peregrine falcon and/or gyrfalcons are monitored at 24 sites (Franke et al 2020).…”