Data from: Waterbird diversity patterns under varied hydrological regimes in Dongting Lake and surrounding lakes

Globally, climate and human-induced environmental changes affect the
populations and distributions of most organisms. This is particularly true
for migratory birds, which change habitats throughout the annual cycle.
Understanding how waterbirds adapt to environmental change is important
for their conservation; however, this subject remains largely unexplored.
Based on wintering waterbirds and environmental data from Dongting Lake
and its surrounding lakes, we compared the changes in waterbird diversity
in subregions with different habitat variations during four hydrological
periods. This allowed us to identify key environmental factors affecting
waterbird diversity and explore the potential mechanisms by which
waterbirds adjust to these environmental changes using the waterbird
habitat patch network method. The results indicated that waterbird
distribution differed across Dongting Lake and the surrounding wetlands
under varying hydrological conditions associated with habitat changes.
Notably, the surrounding lakes with stable habitats served as refuges for
waterbirds during extreme drought, with the percentage of waterbirds
increasing from 9.3 % (late recession) to 63.8 % (extreme drought). Areas
of habitat (i.e., water, mudflat, and vegetation) and human disturbance
were key factors influencing waterbird diversity. As indicated by the
β-diversity of the waterbird-habitat patch network, the waterbird
metacommunity remained relatively stable in terms of spatio-temporal
differences across hydrological periods, while its components displayed
distinct patterns. Specifically, the colonisation component dominated
during extreme drought, whereas the extinction component dominated during
the late recession. Compared to normal recession, an earlier recession led
to a higher proportion of colonisation components. Waterbirds migrated
between habitat patches to adapt to the various hydrological conditions.
This study enriches the theory of community assembly by emphasising the
significance of extinction and colonisation processes shaped by
hydrological conditions. Furthermore, it provides valuable insights into
the conservation and management of waterbird habitats, highlighting the
importance of hydrological dynamics and their impact on waterbird
populations.