The storm (or stormy) petrel (Hydrobates pelagicus) is Europe’s smallest seabird, being only slightly larger than a sparrow. It spends almost its whole life at sea, only coming ashore to breed.
Storm petrels are known to follow ships at sea, in the hope of feeding on marine life that has brought to the surface by the ship’s passage through the water. It was thought be an omen that a storm was on the way. The “petrel” part of the name is a reference to St Peter – when feeding, the bird flits across the surface, appearing to walk on the water in the manner of St Peter’s attempt in the New Testament.
Another name for the bird is “Mother’s Cary’s chicken”. This is thought to be a corruption of “Mater Cara”, meaning “Dear Mother”, which is how sailors might begin a prayer to the Virgin Mary in the hope of surviving the storm that they expected to follow a sighting of the birds out at sea.
The storm petrel measures 14-18 centimetres (5-8 inches) in length. The plumage is sooty-black with a distinctive white band just above the tail that spreads round on either side. There is a prominent wide stripe on the underside of the wings.
The wings and the tail are quite short, with the tail being square-ended. The wingspan is 37-41 centimetres (14-16 inches).
Behaviour and Feeding
The storm petrel has a fluttering flight that has been likened to that of a bat. When feeding, the wings are raised in a V. On the water surface, the bird swims like a duck, riding high.
Storm petrels are usually silent except when breeding, when they call from their burrows with a purring noise.
Storm petrels are often solitary but can also be seen in flocks.
Storm petrels feed mainly on small fish such as herrings and sprats, plus jellyfish and small crustaceans. They will also take waste thrown from ships.
This take place in colonies mainly on small rocky islands off the western coasts of the British Isles. More than two-thirds of the World’s entire population of storm petrels breed in Britain and Ireland.
Nesting takes place in crevices in stone walls, between boulders, or in rabbit burrows.
A single egg is laid, which is incubated by both parent birds in turn, each doing a shift of about three days. The egg hatches after around 40 days.
The parent will leave the chick to hunt for food at sea, only returning to the nest at night. The chick is ready to leave the burrow at around 60 days, after which it is completely independent.
A young storm petrel will not return to the colony for another two or three years, and will not be ready to breed until it is four years old. The lifespan of a storm petrel can exceed 30 years.
After breeding, storm petrels leave British/Irish waters in September or October and head south to winter off South Africa from November until the following March. They will return to their breeding colonies from early May.