Sooty Shearwater (Puffinus griseus)

Sooty Shearwater

[order] PROCELLARIIFORMES | [family] Procellariidae | [latin] Puffinus griseus | [authority] Gmelin, 1789 | [UK] Sooty Shearwater | [FR] Puffin fuligineux | [DE] Dunkler Sturmtaucher | [ES] Pardela sombria | [NL] Grauwe Pijlstormvogel

Subspecies

Genus Species subspecies Region Range
Puffinus griseus Worldwide widespread

Genus

Until recently the shearwaters were devided in two genera Calonectris and Puffinus, but based on dna-analysis Penhallurick and Wink (2004) have proposed a splitting of the shearwaters into three genera: Calonectris for the large shearwaters of the Northern Atlantic, the Mediterranean and the waters around Japan, Ardenna for a group of large Southern Hemisphere breeders and Puffinus for the smaller shearwaters such as the Manx’ group, Audubon’s and Little Shearwaters. This new taxonomy is now widely accepted, but not by all and is stil subject of discussion.

Physical charateristics

A large shearwater. In the Atlantic, the only one that appears uniformly dark sooty brown above and below, with silvery whitish wing linings. Bill and feet dark. This slender, narrow-winged seabird skims on stiff wings over the waves, alternately gliding and flapping.

In calm weather, Sooty Shearwaters fly low over the ocean’s surface with quick, stiff wing-beats. On windy days, they glide over the waves. They are often found in groups of hundreds or thousands, flying in long lines or grouped tightly together on the water. They plunge into the water from a few feet above the surface and swim under water, using their wings to propel themselves. They also dive from the surface, taking prey at surface level, or just below. They sometimes feed near dolphins, whales, or other seabirds.

Listen to the sound of Sooty Shearwater

[audio:http://www.planetofbirds.com/MASTER/PROCELLARIIFORMES/Procellariidae/sounds/Sooty Shearwater.mp3]

Copyright remark: Most sounds derived from xeno-canto

recorded by Ryan Merrill


wingspan min.: 95 cm wingspan max.: 110 cm
size min.: 40 cm size max.: 50 cm
incubation min.: 52 days incubation max.: 57 days
fledging min.: 86 days fledging max.: 57 days
broods: 1   eggs min.: 1  
      eggs max.: 1  

Range

Worldwide oriental region: widespread. It is breeding on islands off New Zealand, Australia and Chile, and the Falkland Islands (Malvinas). In Australia there are colonies on 17 islands (all of less than 1000 pairs), southern Chile (many colonies, some up to 200.000 pairs and up to 4 million birds on Isla Guafo) and the Falklands (10.000-20.000 pairs) and more than 80 colonies in New Zealand.

Habitat

Sooty Shearwaters are widespread at sea and concentrate around upwellings, where cold and warm water masses meet, and over the continental shelf in cooler waters. They may come close to shore where the water is deep. They breed in the far Southern Hemisphere, on islands around Australia, New Zealand, and southern South America, where there is diggable soil for burrows, or rock crevices in which to situate nests.

Reproduction

Colony nester, the Sooty Shearwater nests in the far Southern Hemisphere. Birds typically do not return to their natal colonies until age four. Birds do not breed until they are 5-9 years old. The breeding season lasts from September to May, and during this time, the birds are most active in the colonies at night. The nest is placed in a burrow dug in the soil by both parents. Alternatively, the nest is built in a natural rock crevice. Burrows are dug for breeding under tussock grass, low scrub and on the Snares Islands under Olearia forest. The burrow can be up to ten feet long with a loose nest of grass and leaves at the end of it. Both parents incubate the single egg for 7-8 weeks. Once the egg hatches, both parents feed the young for almost 14 weeks, after which it leaves the island and heads out to sea.

Feeding habits

In the northern Pacific, Sooty Shearwaters feed mostly on small fish, but they also eat crustaceans, shrimp, squid, and jellyfish.

Video Sooty Shearwater

httpv://www.youtube.com/watch?v=wbHWW2lLAN0

copyright: youtube


Conservation

This species is classified as Near Threatened because although it has a very large global population it is thought to have undergone a moderately rapid decline owing to the impact of fisheries, the harvesting of its young and possibly climate change.
Puffinus griseus breeds on subantarctic islands in the Southern Ocean, migrating to the temperate zones of the North Atlantic and North Pacific during its non-breeding season (the boreal summer). It occurs mainly off the North American coast during
the first half of the non-breeding season, and is only present in significant numbers in European waters during (and just prior to) its southern passage (mainly in August- October).
While some non-breeders are present off the Pacific Coast in all seasons, the breeding adults head north in April and May, on their way to the north Pacific where they spend the non-breeding season. The migration occurs in waves of age classes, with the sub-adults moving in the first wave, breeding adults next, and finally the non-breeding adults and fledglings last.
Sooty Shearwater status Near Threatened

Migration

Migratory. Cold-water species, breeding subantarctic; most migrating rapidly across equatorial seas to winter in temperate zones of North Atlantic and North Pacific. In Israel, regular along Mediterranean coast in autumn and winter, and in Gulf of Eilat spring and summer: apparent northward migration from Southern and Indian Oceans into Red Sea (matching that into North Atlantic and North Pacific), and recorded continuing overland whence may reach Mediterranean.
Northward movements begin late March but mostly April-May. Following rapid northward, transequatorial migration up west Atlantic, first arrivals off North American coasts in April and early May, exceptionally March; still largely concentrated off New England and Newfoundland area in June (very few European records then); begins spreading across temperate North Atlantic in July.
Numbers begin decreasing in western North Atlantic in August, when return passage has begun. Others, however, apparently move east since more mid-ocean records in August-September; and then becomes more widespread off north-west European coasts (usually well offshore) including concentrations on Rockall Bank and Faeroese fishing grounds. At same time, southerly movements occur off east Atlantic seaboard south to Morocco, and to lesser extent in North Sea and English Channel. Many fewer North Atlantic flocks in October, and only stragglers November-March.

Distribution map

Sooty Shearwater distribution range map

Leave a Reply

Your email address will not be published. Required fields are marked *