"Whenever you see the Snow petrels
you can be sure that the ice is close by, bergs or the pack; out of the
mist they flit, hover a moment to pick a minute scrap from the water alongside
the ship, and silently vanish like ghosts into the half-gloom. On a clear
day they are conspicuous enough, but in the usual thick weather, when there
is no horizon and you cannot tell sea from sky, everything wrapped in a
pearly illuminescence from which the bergs do not loom up until you are
within quarter of a mile, you may see them one moment, but the next they
have dissolved into the vapour."
L. Harrison Matthews (1951) in
Wandering Albatross: Adventures in the Southern Ocean.
Taxonomy |
Two subspecies:
Greater Snow Petrel P. n. nivea breeds on the Balleny Islands in the Ross Dependency of Antarctica and hybridizes with the other subspecies in some colonies.
Lesser Snow Petrel P. n. minor
breeds widely in Antarctica. Actually show great individual size variation,
the extent of which varies between colonies. Wing length varies from 240
mm to 320 mm. Birds over 280 mm generally considered Greater Snow Petrels.
To add to the problems, there are significant size differences between
males and females.
Identification |
Restricted to cold antarctic waters,
pack ice, icebergs and ice floes. Flocks (sometimes in 1000s) are often
seen sitting on the ridges of icebergs. Generally do not follow ships.
Snow petrels tend to fly low over the water but very high over the land
to avoid predators such as skuas, darting erratically. Enjoy a comparatively
varied diet including fish, cephalopods (squid), marine molluscs, euphausiids,
seal placenta and even the carcasses of dead seals, whales and penguins
and occasionally eat human refuse.
Where and When |
Breed on South Georgia, South Sandwich
Islands, South Orkney Islands, Bouvet Island, the Balleny Islands, and
Scott Island as well as numerous localities on the Antarctic Peninsula
and continent. Single egg is laid in late November to mid-December, in
a simple pebble-lined scrape built in a deep rock crevice with overhanging
protection. Sitting birds spit oil at intruders. Incubation lasts 41-49
days and the chick fledges after an additional 7 weeks (late February to
mid-May).
Photographs on the web |
Adult
on nest From the Ardery
Island Project Homepage.
Literature |
Gilchrist, A. (1952). Occurrence of the Snow Petrel at Heard Island. Emu, 52: p 201-205.
Brown, A.D. (1966). Breeding biology of the Snow Petrel Pagodroma nivea (Forster). ANARE Reports Monograph - 89.
Jones, E. (1980). A survey of burrow-nesting petrels at Macquarie Island based upon remains left by predators. Notornis, 27(1): p11-20.
Cowan, A.N. (1981). Size variation in the Snow Petrel (Pagodroma nivea). Notornis Serial - 283(3): p169-188.
Van Franeker, J.A. and Montague,T. (1987). Recoveries of petrels banded near Casey station, Wilkes Land, Antarctica,1984 to 1985. Corella,11(2): p37-43
Woehler, E.J.(1988). Burrowing petrels surveyed. ANARE News 54: p5.
van Franeker, J.A. and Bell, J.P. (1988). Plastic ingestion by petrels breeding in Antarctica. Marine Pollution Bulletin, 19(12): p672-674.