Kerguelen Petrel (Aphrodroma brevirostris)

Kerguelen Petrel

[order] PROCELLARIIFORMES | [family] Procellariidae | [latin] Aphrodroma brevirostris | [authority] Lesson, 1831 | [UK] Kerguelen Petrel | [FR] Petrel de Kerguelen | [DE] Kerguelen-Sturmvogel | [ES] Petrel de las Kerguelen | [NL] Kerguelenstormvogel

Subspecies

Monotypic species

Genus

Genus Pterodroma, Pseudobulweria and Aphrodroma are also knwon as the Gadfly Petrels. They vary in size from rather small birds such as the Cookilaria-species, measuring about 26 cm, to the much larger and robust representatives of this group like the White-headed Petrel with an overall length of about 43 cm. Their plumages also vary a great deal from species to species; from completely black to light grey mantles and pure white bellies, and with different color phases within species. One feature shared by all of them is the black bill of which the shape also shows much variation. Some species are extremely rare and restricted to a very limited area, other are abundant and wander widely or have unknown pelagic ranges.
The group of the Gadfly Petrels counts over 35 species, mainly from the Southern Hemisphere. There are three genera: Pterodroma with about 30 species, Pseudobulweria counting four and Aphrodroma with only one. Many authors have tried to classify the large number of species of this group and to determine their relationships. This has resulted in a division in several subgenera and the grouping of several species which are considered to have a more or less close relationship. The taxonomic discussion has not come to an end yet: new species have been added or split recently and probably will be in the near future.

Physical charateristics

They are uniformly dark on the upper parts and slightly lighter below, with plumage so shiny that it appears to have white or silvery patches on it. The birds’ large head and steep forehead give them a hooded appearance.


wingspan min.: 80 cm wingspan max.: 82 cm
size min.: 33 cm size max.: 36 cm
incubation min.: 47 days incubation max.: 51 days
fledging min.: 59 days fledging max.: 62 days
broods: 1   eggs min.: 1  
      eggs max.: 1  

Range

Southern Ocean : widespread. Kerguelen Petrel colonies are present on Gough Island (St Helena to UK) in the Atlantic Ocean, and Marion Island and Prince Edward Island (South Africa), and Crozet Islands and Kerguelen Island (French Southern Territories) in the Indian Ocean.

Habitat

Marine and higly pelagic, prefers cold waters; breeds on marshy grounds near sea but also higher up to 450m on volcanic ridges.

Reproduction

The species attends its colonies nocturnally, breeding in burrows in wet soil. The burrows usually face away from the prevailing wind. A single egg is laid per breeding season; the egg is unusually round for the family. The egg is incubated by both parents for 49 days. After hatching the chick fledges after 60 days

Feeding habits

Surf-seizes prey from surface, also known to water-dip. Diet consists mainly of squid, fish and krill.

Video Kerguelen Petrel

httpv://www.youtube.com/watch?v=QEk0CtpltAQ

copyright: Peter Fraser


Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Kerguelen Petrel status Least Concern

Migration

Frequents subantarctic and Antarctic waters S to pack ice all year round. Disperses widely over Southern Ocean to about 30? S; adults less mobile, some visiting colonies throughout year.

Distribution map

Kerguelen Petrel distribution range map

Leave a Reply