Granddad’s Camera
Leach's storm-petrel, as it appears in the game

No.108 · Birds · Rare visitor

Leach's storm-petrel

Hydrobates leucorhous

A dark, fork-tailed seabird with a white rump that flutters over the sea like a huge moth. It lives far out in the ocean, and only comes close to shore when autumn gales blow it in.

When to look

September to October, mostly at dawn and day.

Time of day

Best time
September to November, after a strong north-westerly gale. Watch the sea from a headland in the hours after the wind.
Where in the game
the Pembrokeshire coast (sea)
Size
18–21 cm long
Wingspan
43–48 cm
Lifespan
Averages about 13 years; the oldest known was more than 38 years
Population
Not applicable in Pembrokeshire. Autumn gales have brought 120–122 past Strumble Head on single days (2001, 2010)
Status
Vulnerable globally (IUCN)

Diet

Plankton, including tiny crustaceans, and small lantern fish, picked from the surface as it flutters and hovers

Habitat

Open ocean. Comes to land only to breed, on remote islands, at night

Breeding

Nests in burrows or rock crevices on islands, visiting them only in the dark to avoid gulls and skuas. In Britain, colonies are on St Kilda, North Rona, Sula Sgeir and the Flannan Isles

Field signs

  • A small dark bird with a bounding, jerky, almost bat-like flight over the waves
  • A white rump patch on the back with a fork in the tail
  • Skimming and pattering the surface, often into the wind

Did you know?

  • It is strictly nocturnal at its breeding colonies, and avoids coming to land on clear, moonlit nights.
  • Their telomeres, the protective end caps of chromosomes, lengthen with age, the opposite of most animals.
  • A ringed bird was recaptured over 38 years after it was ringed.

Moments worth waiting for

  • Pattering over the wave September to November, day and dawn
    The petrel skims a wave trough with its feet pattering, its white rump flashing as it turns.

Photo tip

Do not expect a sharp picture on the first try. Use a tripod or a wall for stability, a 500 mm lens, 1/2000 s and an AF mode for small moving subjects. Gale conditions mean you should keep dry gear and a lens cover.

Be a good naturalist

Stay well back from cliff edges in a gale. Do not shine torches at storm-petrels at night, and never use a call recording to attract them. Keep to the coast path.

The law

All wild birds are protected by the Wildlife and Countryside Act 1981

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