Return of the seafarer: Leach’s Petrel

Imagine a bird that lives its entire life at sea – only coming to land at the dead of night to breed, or when driven ashore by storms – but it’s just the size of a Starling. At just 18–21cm in length, the Leach’s Petrel is one of our smallest breeding seabirds. Despite their size, they are hardy, typically living around 13 years in the wild. Unlike the more commonly seen European Storm Petrel, this member of the tubenose family has more pointed wings and a forked tail.

Leach’s Petrel has more pointed wings than a European Storm Petrel, as well as a forked tail. Photo: Steve Young (Alamy Stock Photo)

European Storm Petrel, more commonly seen than a Leach’s Petrel. Photo: Julien Renoult (licenced under CC-zero)

Leach’s Petrels nest in colonies in crevices on remote offshore islands. During breeding season, 94% of the UK’s population nest on the remote archipelago of St Kilda in Scotland. Each female will lay just a single egg between May and July. One parent will incubate while the other forages out at sea, only returning after dark. With limited walking abilities, they ‘shuffle’ to their nest. The cover of the night protects them from predators such as skuas and gulls but makes them hard to see. Instead, they are identifiable by their ‘rattling’ and ‘chattering’ noises.

Hear the chattery rattle of the Leach’s Petrel

The RSPB Magazine · Leach’s Storm Petrel. Audio: Roland Arnison (Xeno-canto)

Despite being one of the most widespread seabirds, the Leach’s Petrel is Red-listed and the UK’s fastest declining breeding seabird. The development of offshore windfarms presents a new threat. Thanks to tagging by the RSPB, we can monitor their movements and assess the threats they face.