Rescue of the Mascarene Petrel, a critically endangered seabird of Réunion Island, Indian Ocean

Abstract

The Mascarene Petrel (Pseudobulweria aterrima), an endemic seabird of Réunion Island, is one of the rarest and least known birds in the world. In this note we report on light-induced mortality in this species at Réunion Island, in the Indian Ocean. Throughout most of the twentieth century, when Réunion Island's population was relatively small, only three birds were found dead or dying. After instituting in 1996 a program encouraging the public to rescue downed seabirds, we received eight Mascarene Petrels, among which seven were banded and released. Four birds were fledglings attracted by lights while on their first flight to sea. These findings show for the first time since the end of the nineteenth century that Mascarene Petrels still breed at Réunion. All fledglings were found in March (late austral summer), suggesting a synchronous summer breeding season. We discuss past and present effects of urban lights on this small population and propose a conservation plan.