Abstract
Climate change is increasingly leading to more extreme weather events,
such as droughts, which pose significant threats to many water bird
species. During the winter season of 2022-2023, Poyang Lake, China’s
largest freshwater lake, faced its most severe drought on record. This
unprecedented event prompted the local government to reaffirm and
intensify their proposal for constructing a dam. To evaluate the
ecological impact of the drought, we used the White-naped Crane
(Antigone vipio) as a case study. By tracking 56 birds with GPS
transmitters, we gathered 268,615 valid location data points recorded at
hourly intervals. We then developed a model system known as
Heterogeneous-Occurrence Species Distribution Models (HOSDMs), which
allows for the prediction of habitat suitability while distinguishing
between different individual occurrence patterns. This methodology was
encapsulated in an R package named migrationR, designed for streamlined
analysis. Our findings indicated that the habitat suitability for
White-naped Cranes reached its lowest point during this exceptionally
dry winter. Reduced water levels forced the cranes to seek alternative
habitats, especially shallow water areas for overnight roosting.
Regarding the debate on the dam construction, we strongly advocate
against an economically driven approach to dam management and instead
support an ecologically focused strategy. Ensuring the preservation of
the annual flooding cycle should be a fundamental requirement for
protecting the habitats of waterbirds.