Cities alter the latitudinal diversity gradient of birds in North America

This is a Preprint and has not been peer reviewed. This is version 1 of this Preprint. You must log in to post a comment. There are no comments or no comments have been made public for this article. This is a Preprint and has not been peer reviewed. This is version 1 of this Preprint. Add a Comment You must log in to post a comment. Comments There are no comments or no comments have been made public for this article. The latitudinal diversity gradient (LDG) is a widely recognized biogeographic pattern, yet its persistence under increasing human impacts remains unclear. Leveraging 17 million eBird records, we investigated how urbanization alters LDGs in North America. We quantified LDGs across 662 cities and their surroundings, and found that LDGs vary by season and native status: non-native species exhibited weak or no LDG, whereas native birds showed the strongest LDG during winter. Notably, native birds showed a significantly flatter winter LDG in cities than in surrounding areas. Although human population density generally reduced bird diversity, it exerted positive effects under cold conditions in high latitudes. These findings indicate that urbanization can reshape classic biodiversity patterns, with cities potentially acting as winter refuges for native birds at higher latitudes. https://doi.org/10.32942/X23D3T Life Sciences Latitudinal diversity gradient, Bird diversity, Urbanization, Human activities, Native status Published: 2026-02-16 23:10 Last Updated: 2026-02-16 23:10 CC BY Attribution 4.0 International Conflict of interest statement: None Language: English