¡¡¡¡Deng, X., Zhao, Q., Fang, L., Xu, Z., Wang, X., He, H., Cao, L. and
Fox, A.D., 2019. Spring migration duration exceeds that of autumn
migration in Far East Asian Greater White-fronted Geese (Anser
albifrons). Avian Research, 10(1), p.19. (°×¶îÑ㣬26g)
¡¡¡¡Migration theory suggests, and some empirical studies show, that in
order to compete for the best breeding sites and increase reproductive
success, long-distance avian migrants tend to adopt a time minimization
strategy during spring migration, resulting in shorter duration spring
migration compared to that in autumn. Using GPS/GSM transmitters, we
tracked the full migrations of 11 Greater White-fronted Geese (Anser
albifrons) between southeast China and the Russian Arctic, to reveal the
migration timing and routes of the East Asian population, and compare
the difference in duration between spring and autumn migration of this
population. We found that migration in spring (79?¡À?12 days) took more
than twice as long to cover the same distance as in autumn (35?¡À?7
days). This difference in migration duration was mainly determined by
significantly more time spent in spring (59?¡À?16 days) than in autumn
(23?¡À?6 days) at significantly more stopover sites. We suggest that
these geese, thought to be partial capital breeders, spent almost three
quarters of total migration time at spring stopover sites to acquire
energy stores for ultimate investment in reproduction, although we
cannot reject the hypothesis that timing of the spring thaw also
contributed to stopover duration. In autumn, they acquired necessary
energy stores on the breeding grounds sufficient to reach Northeast
China staging areas almost without stop, which reduced stopover times in
autumn and resulted in the faster autumn migration than spring.