Abstract: Wetland birds play an important indicative role in wetland ecosystems, and their diversity monitoring is beneficial for wetland conservation. Taking Suzhou City as the research area, a maximum entropy model was employed to simulate and analyze the spatial distribution patterns and spatiotemporal variation of 41 water bird diversity hotspots in 2018, 2019, and 2020. Environmental variables, including annual average precipitation, point of interest (POI) kernel density, land use type, and proximity to water source, wield substantial influence over the birds' spatial distribution. Over the triennium, primary influencing factors exhibited noteworthy fluctuations, while anthropogenic disturbances demonstrated a more consistent profile. Notably, the spatial extent of waterbird diversity hotspots demonstrated a progressive expansion, primarily concentrated along the northern coastal wetlands of the Yangtze River and the expansive lake wetlands surrounding Taihu Lake in the southwest. This trend is anticipated to intensify further. Comparative analysis of hotspot distribution between migratory and resident waterbirds, notably dominated by species such as Alcedo atthis, Egretta garzetta, Amaurornis phoenicurus, and Podiceps ruficollis, reveals larger hotspots for the latter group. Given the burgeoning hotspot areas, monitoring points established in 2019 are deemed insufficient for comprehensive waterbird surveillance in Suzhou. Consequently, it is recommended to add 15 monitoring areas, including Shuangshan Island area, Tongsha Wharf area, and Wangyu River.

Key words: bird diversity hotspot, maximum entropy model, temporal and spatial change, spectral unmixing, Suzhou