The Amur Paradise Flycatcher ( Terpsiphone incei ) with distinct male dichromatism: implications for nest-site selection and nesting success

Abstract

Nest-site selection plays a crucial role in reproductive success and survival of birds, particularly for territorial birds. Therefore, it is important to understand how birds identify and select their nesting sites. The Amur Paradise Flycatcher ( Terpsiphone incei ) is a medium-sized species of the Monarchidae family with dichromatism in males. To investigate the differences in nest-site utilization strategies between different male morphs and identify the nest-site variables that influence the nest success of the species, we conducted a study on nest-site selection and nest success during the breeding seasons of 2020 to 2022 in Yangxian County, Shaanxi Province, China. During our study, we recorded a total of 98 nests and found that the Amur Paradise Flycatcher preferred nesting in forests with lower illumination, specifically on cedrela trees, and exclusively near residential areas. Interestingly, we did not find any significant difference both in nest-site selection and nesting success between the two male morphs. The overall nesting success was 51.06% (n = 94), with nest predation being the primary cause of nest failure. Our principal component analysis identified several significant factors affecting nest-site selection, including nest tree factors (14.168%), interference factors (13.145%), nest concealment factors (10.87%), terrain factors (10.262%), altitude factors (10.046%), and stability factors (8.438%). Furthermore, the results of binary logistic regression analysis indicated that successful breeding nests were located closer to the forest edge, had a sunnier aspect, and a smaller slope compared to failed nests. Similarly, the multiple linear regression analysis showed that slope, aspect, and nest tree species had significant effects on breeding success. Our findings suggest that the Amur Paradise Flycatcher seeks a balance between nest concealment and a view of the surroundings. The lack of a significant difference in reproductive outcomes between the two male morphs could potentially be attributed to the greater experience of white morph individuals, which may help mitigate the higher risk with their more attractive plumage for predators. Understanding the factors affecting nest-site selection and nest success is crucial for conservation efforts aimed at protecting this fascinating species and ensuring its long-term survival.

Keywords

• amur paradise flycatcher
• dichromatism
• nest-site selection
• nest success