Breeding biology of Tristram's storm-petrel (Oceanodroma tristrami) in a changing environment

Abstract

The effects of invasive ants on the nesting success of Tristram's Storm-petrel (Oceanodroma tristrami) were documented over the course of two breeding seasons on Laysan and Tern Islands, Northwestern Hawaiian Islands. On Laysan Island, Monomorium pharaonis was responsible for 1% of nest failures and did not significantly affect Tristram's Storm-petrel breeding success. On Tern Island, Pheidole megacephala was not found to affect nesting Tristram's Storm-petrels. Despite these findings, more research is required to examine the effects of weather and seasonality on these relationships. Tristram's Storm-petrel had a relatively low reproductive rate on Laysan (0.16), Tern (0.28), and East (<0.22) islands. Nest abandonment was the greatest cause of nest failure followed by nest site competition with larger burrowing seabirds and weather effects. Future research should focus on Tristram's Storm-petrel demography, age of first breeding, and breeding success on islands with different topography such as Nihoa. Six and five species of ant were recorded on Laysan and Tern Islands, respectively.