Avian resilience to tourism development disturbances in Qilihai Wetland, Tianjin

Avian species exhibit differential responses to anthropogenic disturbances. Based on the bird survey data from Qilihai Wetland in Tianjin across three distinct phases, that is wetland park pre-development (2004-2007), development/operation phase (2009-2015), and restoration/conservation phase (2016-2023), this study investigated the relationship between avian biological traits and disturbance resilience to human activities through cluster analysis, univariate and multiple linear regression analysis. The findings revealed that: 1) The number of avian species in Qilihai Wetland across the three phases was 190, 159, and 175, respectively, showing an initial decline followed by partial recovery. 2)Avian responses to tourism development disturbances were clustered into five patterns: 30 species persisted, 39 species left temporarily and returned during disturbances, 72 species returned after disturbances, 55 species left permanently, and 51 species came after restoration. 3)The disturbance resilience grade of the first four types was quantified, and their relationship with avian biological traits was analyzed by regression analysis. The results indicated no significant correlation (P>0.05) between residency type and disturbance resilience grade. However, clutch size showed a significant positive correlation (P<0.05) with disturbance resilience grade. Among 28 bird species with larger clutch sizes (≥8), only 2 left permanently. Waterfowl, wading birds, omnivorous birds, and floating-nest birds showed significant positive correlation (P<0.05) with disturbance resilience grade. 52.83% of waterfowl, 33.84% of wading birds, as well as 50% of floating-nest birds, either persisted or left temporarily and returned, while omnivorous birds were less sensitive to disturbances. Ground-nesting and woven-nest birds showed significant negative correlation (P<0.05) with disturbance resilience grade, with 61.4% of ground-nesting birds and 45.8% of woven-nest birds either left permanently or returned after disturbances. 4) Habitat suitability and food resource availability emerged as critical determinants of avian disturbance resilience, and the protection degree and endangerment status were also important references for understanding the discrepancies in disturbance response. The study demonstrates that the biological and ecological traits at the avian species level can reveal differences in their resilience to disturbances.