Mammalian predators and vegetated nesting habitat drive reduced protected area nesting success of Kentish plovers, Yellow Sea region, China

Protected areas provide essential habitats for wildlife by conserving natural and semi-natural habitats and reducing human disturbance. However, whether breeding birds vulnerable to nest predation can benefit from strict land management in the protected area is unclear. Here, we compare the nesting performance of two groups of a ground-nesting shorebird, the Kentish plover (Charadrius alexandrinus), in the protected area (Liaohekou Natural Reserve, hereinafter PA), and the control non-protected area (non-PA) around the Liaohekou Natural Reserve, in the north of the Yellow Sea, China, and identify which environmental factors, such as nesting habitat and nest materials, influence the daily nest survival rate (DSR). We found similar nesting habitats in both study areas, dominated by bare land or Suaeda salsa grassland. However, DSR was lower in PA (0.91 +/- 0.01) than in non-PA (0.97 & PLUSMN; 0.01). Kentish plovers nesting in areas with vegetation cover experienced lower DSR than in bare lands in both areas, and nests built with materials of S. salsa sticks had the lowest DSR in the bare land. Data from infrared cameras confirmed relatively higher predator abundances and nest predation rates by nocturnal mammals, such as Eurasian badgers (Meles meles), in PA than in non-PA, and this pattern was especially evident for plover nests located in S. salsa grassland. Our results suggest that Liaohekou Natural Reserve protected area may not necessarily provide safe nesting sites for Kentish plovers due to the abundance of generalist mammal nest predators. However, the PA includes about 80% of the nests from both locations. This means the contribution of the total number of successful nests continues to be much higher within PA, with the benefit for the species that this brings in terms of conservation. The variation and mechanisms underlying differences in the nest predator communities of PA and non-PA deserve further study.

Automated summary

Protected areas serve as important habitats for wildlife by conserving natural habitats and reducing human disturbance. However, the effect of strict land management in protected areas on breeding birds vulnerable to nest predation is unclear. In this study, we compared the nesting performance of Kentish plovers in a protected area (PA) and a non-protected area (non-PA) and identified the environmental factors influencing nest survival rate. The results showed that the PA had a lower nest survival rate compared to the non-PA, indicating that the protected area may not provide safe nesting sites for Kentish plovers due to abundant nest predators. Nonetheless, the PA still contributed to a higher number of successful nests, benefiting the conservation of the species. Further research is needed to understand the differences in nest predator communities between the PA and non-PA.