Multi-guild waterbird habitat suitability change and hotspots (2018–2024) in China's international wetland cities: MaxEnt + Gi* within a DIKW framework

The implementation of International Wetland City certification and associated conservation measures coincided with changes in the potential distribution of waterbirds in China's coastal wetlands. However, it remains unclear how the certification affects the overall distribution patterns of multi-species waterbird habitats and the specific mechanisms by which different species respond to environmental factors. Moreover, identifying key habitats for these guilds is essential for targeted species conservation and habitat restoration. Therefore, based on the Data-Information-Knowledge-Wisdom (DIKW) framework, this study classified 166 waterbird species into four ecological guilds: shorebirds, wading birds, open-water birds, and waterfowl. Using a coupled MaxEnt and hotspot analysis approach, we evaluated habitat suitability for these four waterbird guilds before and after the designation of Panjin, Dongying, and Yancheng as International Wetland Cities (2018–2024) and identified their distribution hotspots.The results indicated that: (1) After 10 iterations of training, the MaxEnt models for all four waterbird guilds achieved a mean AUC above 0.8 and a mean TSS above 0.60, demonstrating good predictive accuracy in simulating waterbird habitats. From 2018 to 2024, the total area of suitable waterbird habitat increased significantly in Panjin, Dongying, and Yancheng, with net expansions of 346.26 km 2 , 602.48 km 2 , and 40.51 km 2 , respectively; (2) Pronounced regional heterogeneity was evident in waterbird distribution patterns across the wetland cities. In Panjin, waterbirds showed a stronger preference for natural habitats such as herbaceous marshes and tidal flats, whereas in Dongying and Yancheng, they demonstrated greater adaptability, with a marked increase in occurrence probability in human-modified landscapes such as cropland; (3) Suitable waterbird habitats in all three wetland cities demonstrated a spatial pattern of “overall improvement despite localized contraction.” Although some coastal areas experienced partial habitat loss, these habitats continued to expand inland, with shorebirds facing the more significant pressure from habitat contraction, particularly in coastal zones; (4) Land use/land cover (LULC) and distance to farmland (DFC) were the dominant factors influencing waterbird distribution in Panjin. In Dongying, distribution was significantly affected by LULC, distance to roads (DFR), NDVI, mean diurnal range (BIO2), and precipitation seasonality (BIO15). In Yancheng, habitat selection was primarily influenced by climatic factors such as BIO2 and isothermality (BIO3), as well as DFC and distance to constructed surfaces (DFS); (5) Hotspots of suitable waterbird habitat continued to expand, forming a trend centered on nature reserves and gradually extending outward.This study reveals the spatiotemporal evolution patterns and driving mechanisms of habitat suitability for multiple waterbird guilds under the context of International Wetland City designation, identifies key habitat hotspots, and provides specific recommendations for the conservation and management of waterbird habitats in internationally recognized wetland cities. • Employing the Data–Information–Knowledge–Wisdom (DIKW) framework to evaluate waterbird habitat suitability. • Identifying key hotspot areas of waterbird habitats through coupled MaxEnt model and hotspot analysis. • Total suitable waterbird habitat area increased by 346.26 km 2 in Panjin, 602.48 km 2 in Dongying, 40.51 kmkm 2 in Yancheng. • Cropland has emerged as a crucial novel habitat for waterbirds in Dongying and Yancheng. • Designating International Wetland Cities helps conserve and restore waterbird habitats.