Invasive smooth cordgrass (Spartina alterniflora) has been expanding rapidly through the coastal wetlands of eastern China and these changes negatively affect local birds. In the Dafeng Milu National Nature Reserve (henceforth referred to as DMNNR), rapid degradation of spartina occurs after an increase in milu (Elaphures davidianus; hereafter elk) numbers and ecological hydrological engineering. We evaluated the impact of such degradation on the abundance and species diversity of birds in the DMNNR during 2017–2021. We found that the area covered by S. alterniflora decreased significantly in the study area at a rate of 310 ha per year and by 62% during 2017–2021 (p < 0.01). With this decrease in the S. alterniflora area, the species richness and abundance of birds first increased and then decreased. Songbird density clearly decreased but species richness did not significantly do so. This research demonstrated that during the initial stages of vegetation degradation, there was a positive effect on bird diversity. With the increasing vegetation degradation increases, both songbirds and waterbirds experience negative impacts. The DMNNR is an important stopover site for waterbirds in the East Asian–Australasian Flyway, and additional measures are needed to control vegetation degradation and to restore the native habitats for birds.

Tiaozini, the core area of the Yellow (Bohai) Sea Migratory Bird Habitat in Dongtai, Jiangsu province and a World Heritage Site, has provided an ideal habitat for migratory birds. As an important hub on the East Asian–Australasian Flyway (EAAF), Tiaozini wetland provide pivotal stopover and wintering sites for tens of thousands of migratory waterbirds, including some global critically endangered species such as Spoon-billed Sandpiper (Calidris pygmaea) and Spotted Greenshank (Tringa guttifer). Although many researchers have conducted a lot of studies on waterbirds in Tiaozini wetland, there is still lack of a dataset on waterbird species composition and individual quantity in Tiaozini wetland throughout the year. Here, we conducted a one-year waterbird survey in the Tiaozini wetland during 2020-2021, and provided an occurrence dataset with detailed species and geographic information. This occurrence dataset is the first public record of species and number of waterbirds in Tiaozini Wetland for a whole year, which include the taxonomic information, location information, number, Investigation date and endangered level for each species. All data have been published on GBIF.

Fishery bycatch is a significant threat to biodiversity, with birds being frequent casualties. Current research mainly focuses on seabird bycatch in large-scale marine fisheries, while bird bycatch in inland freshwater areas remains poorly understood. Crayfish traps are extensively used in China’s freshwater environments, but their ecological impacts on birds are overlooked due to monitoring difficulties. Through iEcology approaches, we collected and analyzed 146 bird bycatch incidents in crayfish traps from Chinese social media platforms between September 2010 and December 2023. The results revealed 420 identified birds from 62 species (11 orders, 24 families), predominantly omnivorous and carnivorous, while 106 individuals could not be identified. Cases were concentrated in the middle and lower reaches of the Yangtze River, showing significant positive correlations with water area ratio and aquaculture production (p < 0.001). During fishing seasons, the number of cases, species, and individuals were significantly higher (p < 0.001), though mortality rates increased in off seasons. The middle and lower reaches of the Yangtze River are main production areas of red swamp crayfish (Procambarus clarkii) and Chinese mitten crab (Eriocheir sinensis), where intensive use of crayfish traps may increase bird bycatch risk. Despite existing regulations, systematic supervision is needed to minimize ecosystem impacts.