Skip to content

Decades of Monitoring Reveal Long-Term Snow Bunting Decline on Flatey, Iceland

Snow bunting in breeding plumage on rocky tundra in Dovrefjell
Research · Ecology

Long-term demographic data for the snow bunting (Plectrophenax nivalis) have revealed a sustained decline at an Icelandic breeding site and provided the first published estimates of adult survival for the species.

The researchers combined capture–mark–recapture and dead-recovery records from two wintering sites in northeast Iceland with breeding-site data from Flatey in the west. The datasets stretch back to the 1970s and early 1980s, with breeding records continuing through 2023.

Adult survival estimates differed among the three datasets

Estimated annual apparent adult survival was about 64% at Stórutjarnaskóli and 54% at Akureyri, while the estimate from the Flatey breeding site was about 43%. Apparent survival is the probability that a bird both survives and remains available to be detected at the study site. Uncertainty around the estimates overlapped substantially, and the sites were monitored during different periods, so the values should not be treated as a simple ranking of survival between places.

Breeding-pair counts showed a clear long-term decline on Flatey

The clearest long-term pattern comes from Flatey. Breeding-pair counts from 1975 to 2023 showed a clear decline even after the researchers accounted for variation in search effort. Recapture rates at the wintering sites also fell markedly after about 1990, which could reflect lower abundance, reduced site fidelity or increasing trap avoidance.

The authors note that apparent survival combines true mortality with emigration because site fidelity could not be estimated. They also caution that the two winter sites were monitored in different periods, so site and time are confounded when their survival estimates are compared. The long-term data establish the first adult-survival baseline for Icelandic snow buntings and document a clear long-term decline in breeding pairs on Flatey.

Sources and image credit

  1. Thorstensen, S., Petersen, A., Mallory, M. L., Robertson, G. J., Calvert, A. M., & Gutowsky, S. E. (2026). Adult snow bunting survival and population change from decades of monitoring effort in Iceland. Arctic Science, 12, 1–7. https://doi.org/10.1139/as-2025-0100Primary peer-reviewed open-access study; Version of Record published online 30 April 2026.

Image: Bouke ten Cate — snow bunting in breeding habitat in Dovrefjell–Sunndalsfjella, Norway; representative image, not a bird from the Icelandic study. Source: Wikimedia Commons. · CC BY-SA 4.0 · Source

About this content: This story was produced with AI assistance within an editorial workflow developed by Wildlife Vagabond. Editorial responsibility remains with Wildlife Vagabond.How AI is used

Ecology

SPECIES IN THIS STORY

Species in this story

Snow Bunting Plectrophenax nivalis Explore species

Independent research and conservation news archive

Did you find this information useful?

Wildlife Vagabond is independently built and maintained. Voluntary support helps cover source verification, hosting and continued work on research and conservation news.

Support Wildlife Vagabond

The news archive will remain freely available.