Seasonal and population differences in migration of Whimbrels in the East Asian–Australasian Flyway
Time:2021-05-10Source: 原创 Hits:
Kuang, F., Coleman, J.T., Hassell, C.J., Leung, K.S.K., Maglio, G.,
Ke, W., Cheng, C., Zhao, J., Zhang, Z. and Ma, Z., 2020. Seasonal and
population differences in migration of Whimbrels in the East
Asian–Australasian Flyway. Avian Research, 11(1), pp.1-12.
(中杓鹬,HQPG2009P, 9g)
Conserving migratory birds is challenging due to their reliance on
multiple distant sites at different stages of their annual life cycle.
The concept of “flyway”, which refers to all areas covered by the
breeding, nonbreeding, and migrating of birds, provides a framework for
international cooperation for conservation. In the same flyway, however,
the migratory activities of the same species can differ substantially
between seasons and populations. Clarifying the seasonal and population
differences in migration is helpful for understanding migration ecology
and for identifying conservation gaps. Methods Using satellite-tracking
we tracked the migration of Whimbrels (Numenius phaeopus variegatus)
from nonbreeding sites at Moreton Bay (MB) and Roebuck Bay (RB) in
Australia in the East Asian–Australasian Flyway. Mantel tests were used
to analyze the strength of migration connectivity between the
nonbreeding and breeding sites of MB and RB populations. Welch’s t test
was used to compare the migration activities between the two populations
and between northward and southward migration. Results During northward
migration, migration distance and duration were longer for the MB
population than for the RB population. The distance and duration of the
first leg flight during northward migration were longer for the MB
population than for the RB population, suggesting that MB individuals
deposited more fuel before departing from nonbreeding sites to support
their longer nonstop flight. The RB population exhibited weaker
migration connectivity (breeding sites dispersing over a range of 60
longitudes) than the MB population (breeding sites concentrating in a
range of 5 longitudes in Far Eastern Russia). Compared with MB
population, RB population was more dependent on the stopover sites in
the Yellow Sea and the coastal regions in China, where tidal habitat has
suffered dramatic loss. However, RB population increased while MB
population decreased over the past decades, suggesting that loss of
tidal habitat at stopover sites had less impact on the Whimbrel
populations, which can use diverse habitat types. Different trends
between the populations might be due to the different degrees of hunting
pressure in their breeding grounds. Conclusions This study highlights
that conservation measures can be improved by understanding the full
annual life cycle of movements of multiple populations of Whimbrels and
probably other migratory birds.