Migratory herbivorous waterfowl track multiple resource waves during spring migration

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2030)

Published: Sept. 1, 2024

East Asian herbivorous waterfowl intensively use farmland in spring, next to their natural habitat. Accordingly, they might have expanded migration strategy from merely tracking the green wave of newly emerging vegetation also incorporating availability post-harvest agricultural seeds (here dubbed seed wave). However, if and how multiple food resources time seasonal is still unknown. We test this using 167 spring tracks five species mixed-effect resource selection function models. found that all study arrived at core stopover sites Northeast China Plain after became available, extended stay emerged breeding around emergence vegetation. At sites, used snowmelt as a cue track availability, although smaller-bodied tended arrive later. swans tracked onset geese mid- or end phases snowmelt. Our findings suggest waves fine-tune migration, highlighting new opportunities for conservation.

Language: Английский

High variability of migration strategies in a re-established Cygnus buccinator (Trumpeter Swan) population

Ornithology, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 22, 2024

ABSTRACT The interior population (IP) of Cygnus buccinator (Trumpeter Swan), formerly extirpated by market hunting, was reestablished in eastern North America releasing individuals from both migratory and nonmigratory populations. Their current annual movement patterns are largely unknown. We deployed 113 Global Positioning System–Global System for Mobile Communications transmitters on IP C. 6 U.S. states 1 Canadian province across the breeding range. Using data 252 “swan-years,” we estimated migration phenology using piecewise regression models fit to each yearly time series displacement site. a latent-state model characterize population-level associations between latitude maximum extent migration, linear mixed quantify individual characteristics (e.g., status sex) phenology. At level, 59% swans moved distant nonbreeding period areas (long-distance defined as moving >100 km site), 16% exhibited regional (25–100 19% but local movements (<25 6% multiple strategies. Swans at more-northern latitudes departed their territories earlier autumn, returned later spring, migrated farther than those more southern latitudes. Although association positive, some remained close location site during period. Breeding autumn nonbreeders, did not have strong with arrival spring. partial migrants, continuum strategies that vary latitudinally, long-distance migration. Much variability is related factors tied natural history demands status) response environmental conditions through latitude).

Language: Английский