Identification of bird conservation gaps of protected areas in high-intensity development area: A case study of Tianjin, China.

Due to the long-term disturbance of human activities, natural habitats in the high-intensity development areas have been seriously degraded, causing serious threat to local biodiversity. The conservation efficiency of natural reserves in these regions needs to be improved urgently. Scientific evaluation of conservation efficiency of nature reserves and identification of biodiversity conservation hotspots and conservation gaps in high-intensity development areas are of great significance to sustainable development of urbanization. With birds as the indicator group for biodiversity, we used MaxEnt and InVEST models to calculate the hot spots of bird diversity and habitat quality, and compared with current boundaries of protected areas in Tianjin to accurately identify the conservation gaps. The results showed that 228 bird species belonging to 54 families and 19 orders were recorded. All kinds of natural and artificial wetlands in the coastal area were the most suitable habitats for birds, accounting for 66.8% of bird diversity hotspots in Tianjin, and the artificial wetlands of reservoirs and fish ponds had high suitability as bird habitats due to sufficient food sources, which indicated that moderate anthropogenic interference would improve species diversity. The coverage rate of protected areas for bird diversity hotspots was only 37.7% in Tianjin, which indicated a serious conservation gap. The gaps mainly included wetlands in Dashentang and Lin'gang areas, the river junction and the estuary wetland, which should be planned as the key protected areas in the future. The method of collaborative analysis of the two models could improve the identification accuracy in detecting the conservation gaps and has certain universality for improving the efficiency of biodiversity conservation in high-intensity development areas.