WatchList Species Account for Bermuda Petrel (Pterodroma cahow)

Qualifies for the list as a Red List Species

Photo: © Jeremy Madeiros

Bermuda’s only endemic breeding species, the Bermuda Petrel was once abundant throughout the main island and the smaller satellite islands but exploitation for food by the early settlers, burning and deforestation and the introduction of pigs, rats, cats and dogs soon eliminated most of its population. For 300 years it was thought extinct but a specimen was found in 1935 and 18 pairs were rediscovered in 1951 nesting on rocky islands in Castle Harbor totalling only 1 ha in size.

Under the direction of David B. Wingate, who has worked on the species for over 30 years and has saved it from extinction, intensive management had by the 1990s increased its numbers at its breeding site to 53 pairs; the total population is estimated to be around 180 individuals. It formerly nested in soil burrows but this habitat is not available on its current and suboptimal sites, where it nests in limestone crevices and artificial burrows.

Among the threats to the species are competition for nest sites with the White-tailed Tropicbird and light pollution from the nearby airport and a U.S. Naval Air Station, which negatively impacted nocturnal courtship; the lights at the latter are now turned off during the breeding season. There is a threat of sea-level rise and increased storm activity. In recent years there have been several instances of burrows being flooded, something which had not happened in the previous 25 years. Construction of a sea-wall on one islet has prevented flooding and destruction of nests there. In addition contaminants may result in lowered nesting success.

There is an active program to provide artificial burrows that exclude tropicbirds; rats are periodically removed from the islets. There are plans to establish a colony on Nonsuch Island, which could accommodate 1,000 pairs. During the nonbreeding season it apparently wanders to the offshore Atlantic waters of the southeastern U.S.