A spatialized digital database for all bird species in China.

Area of Science:

• Ornithology
• Biodiversity Informatics
• Zoogeography

Background:

• Existing national bird distribution data in China uses coarse provincial-level units, limiting research precision.
• This spatial aggregation can lead to inaccurate distribution findings for many avian species.

Purpose of the Study:

• To develop a spatially refined bird distribution database for China at the county level.
• To improve the accuracy of avian distribution data for 1,371 species.

Main Methods:

• Integrated multi-source bird distribution data, including handbooks, literature, fauna/avifauna records, scientific papers, citizen science observations, GPS tracking, and website data.
• Compiled a database covering 2,908 counties, detailing taxonomy, distribution, and data sources for each species.
• Validated and enriched existing distribution records with new observational data.

Main Results:

• The new database includes 1,371 bird species across 2,908 Chinese counties.
• A significant finding is that 835 species (61%) were recorded outside their previously known distribution ranges.
• Increased observational frequency and individuals were noted in under-surveyed areas, particularly in Western China, at higher altitudes and latitudes, including waterfowl range expansion into Xinjiang.

Conclusions:

• The county-level bird distribution database provides a significant advancement over provincial-level data.
• This dataset corrects previous distribution inaccuracies and highlights previously undetected species occurrences and range shifts.
• Offers a foundational resource for detailed ornithological research and conservation planning in China and internationally.