Nest-site selection and its influence on breeding success in a poorly-known and declining seabird: The Tahiti petrel Pseudobulweria rostrata

PLoS One. 2022 Apr 27;17(4):e0267408. doi: 10.1371/journal.pone.0267408. eCollection 2022.

Abstract

The Tahiti petrel (Pseudobulweria rostrata) is a rare and declining seabird whose breeding biology and nest-site selection are poorly known. Nest-site selection is critical to seabird population fitness, and understanding the factors driving it is essential for designing effective conservation measures. Here, we measured several variables (topographical, physical and environmental) to characterize Tahiti petrel nesting habitats and burrows (i.e., width, height, depth and type: rocky cavity, dug into the soil or under a root) on Nemou Island in New Caledonia. The data were clustered using the HCPC (Hierarchical Clustering on Principal Component) method to identify principal habitat groups. This method was combined with logistic regressions to examine the influence of the variables on nest-site selection and breeding success. Our results showed that nest-site selection is linked to habitat groups (a combination of substrate and vegetation data), slope, orientation and soil depth, while breeding success is only influenced by nest characteristics (i.e., burrow type and width). Tahiti petrels prefer to nest on steep slopes in mature forests with rocky substrate and deep soil. Burrows were scatterred in small sub-colonies or isolated pairs, suggesting that nest-site selection depends on habitat quality rather than conspecific density. The study also revealed that breeding success is lower in rocky cavities and increases in burrows with wide entrances. Our nest-site selection survey is the first for the genus Pseudobulweria, and provides critical information for designing effective conservation programs in New Caledonia and the Pacific.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Birds*
  • Ecosystem
  • Nesting Behavior*
  • Polynesia
  • Soil

Substances

  • Soil

Grants and funding

Funds and support for this study were mainly provided by the Province Sud (PhD scholarship to A.P.), the CNRT “Nickel et son environnement” and the DAFE-NC. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.