Climate-driven flyway changes and memory-based long-distance migration

Abstract

Millions of migratory birds occupy seasonally favourable breeding grounds in the Arctic 1 , but we know little about the formation, maintenance and future of Arctic bird migration routes and genetic determinants of migratory distance. Here, we established a continental-scale migration system, satellite tracking 56 peregrine falcons (Falco peregrinus) from six Eurasian Arctic breeding populations and resequencing 35 genomes from four of these. Different breeding populations used five migration routes across Eurasia, likely formed by longitude and latitude breeding ground shifts during the LGM-Holocene transition. Contemporary inter-route environmental divergence appears to maintain distinct migration routes. We found that the novel gene ADCY8 was associated with population-level migratory distance differences. We elucidated its regulatory mechanism and found the most likely selective agent for this divergence was long-term memory. Global warming is predicted to influence migration strategies and diminish breeding ranges of Eurasian Arctic peregrines. Harnessing ecological interactions and evolutionary processes to study climate-driven changes in migration can facilitate the conservation of migratory birds.

Exploring the Role of Cognition in the Annual Fall Migration of the Monarch Butterfly (Danaus plexippus)

“…Sex differences in long-term visual memory related to mate search are well known in bird and mammals [44]. Long-term visual memory has also been shown to play a major role in the navigational system of many migratory bird species [20,45], and may play a similar role in the navigational mechanism of monarchs. Further empirical examination of spatial abilities in non-migrant and migratory monarchs would be beneficial and provide further insight into potential cognitive adaptations to a migratory lifestyle in this iconic insect species.…”

Birds use individually consistent temperature cues to time their migration departure

“…However, understanding how individual reaction thresholds are established, as well as the contribution of genetics, environment, and learning, requires further investigation. Genetics can contribute to migration distance (wintering latitude) in this species ( 30 ) and others ( 31 ), raising the possibility that wintering latitude and the individual’s temperature cue threshold may be genetically linked. However, early life experiences may also shape an individual’s phenotypic responses to temperature cues, given the geographic spread and potential uncertainties in the locations of wintering sites available to naïve juveniles on their first migration ( 32 ).…”

First tracking of declining Caspian terns Hydroprogne caspia breeding in the Baltic Sea reveals high migratory dispersion and disjunct annual ranges as obstacles to effective conservation

“…Routes were classified by visually inspecting the general direction and the geographical areas traversed by the tracks across Europe and Africa. Then we checked this classification by hierarchical clustering with the heatmap () function of measured Hausdorff distances between all possible pairs of individual tracks using the package pracma in R as in Gu et al (2021). We continued our analyses on routes based on our qualitative method, which was fully supported by the quantitative approach for spring tracks and more roughly in autumn due to the convergence of the more western routes in the Inner Niger River Delta (Results section and Supporting information).…”