Huttons Shearwater (Puffinus huttoni)

Huttons Shearwater

[order] PROCELLARIIFORMES | [family] Procellariidae | [latin] Puffinus huttoni | [authority] Mathews, 1912 | [UK] Huttons Shearwater | [FR] Puffin de Hutton | [DE] Hutton-Sturmtaucher | [ES] Pardela de Hutton | [NL] Huttons Pijlstormvogel

Subspecies

Genus Species subspecies Region Range
Puffinus huttoni PO sw

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

The Hutton’s shearwater is a small “black and white” shearwater, 36-38 cm in length with a wingspan of about 75 cm. The upperparts are uniform brownish black. The dark brown of the cap extends below the eye merging into the white of the chin and throat. The dark hindneck extends down behind the cap to form a broad collar almost encircling the neck and upper breast. The rest of the underbody extending from the lower breast to the undertail coverts is white except for a small dark patch on the thigh and the sides of the undertail coverts. The underwing is offwhite with broad brownish borders with extensive dusky grey armpits. Bill is long, slender, and dark grey. Iris brown. Leg is light to dark pink and mauve on the inside and pink and dark grey outside; feet pink with black webs.

Listen to the sound of Huttons Shearwater

[audio:https://planetofbirds.com/MASTER/PROCELLARIIFORMES/Procellariidae/sounds/Huttons Shearwater.mp3]

Copyright remark: Most sounds derived from xeno-canto


wingspan min.: 73 cm wingspan max.: 77 cm
size min.: 36 cm size max.: 38 cm
incubation min.: 50 days incubation max.: 60 days
fledging min.: 75 days fledging max.: 85 days
broods: 1   eggs min.: 1  
      eggs max.: 1  

Range

Pacific Ocean : Southwest. The only place in the world that this species breeds is high in the Seaward Kaikoura Ranges at elevations between 1200 to 1800 meter.

Habitat

It digs its burrows on gentle to steep mountain slopes at 1,200-1,800 m, under tussock grass or low alpine scrubland

Reproduction

An adult pair of shearwater will lay a single egg anywhere between the end of October to mid November. The egg is laid in a hollowed out chamber at the end of a burrow up from 60cm to 250cm in length. The nest is made of tussock grass and sticks, lined with feathers. The eggs are incubated for 50-60 days and the chicks, covered in soft grey down, are raised by both parents for 80 days until they are ready to leave the nest. When the chicks have reached a suitable weight and are fully feathered, they will leave the colony at night and fly to the ocean. From this moment they are totally independent of their parents. It is thought that shortly after this time the fledgling will leave the country and fly to Australia, returning after 3 or 4 years to breed. Adults also make this journey every year but stay only for the non-breeding season.

Feeding habits

It feeds mostly on small fish and krill

Video Huttons Shearwater

httpv://www.youtube.com/watch?v=nGl68LucQck

copyright: Brooke Clibbon


Conservation

Although this species has a stable population, habitat changes are still occurring through continued, although much reduced, erosion and vegetation regeneration as a result of herbivore control. It qualifies as Endangered because breeding is restricted to just two colonies which may be losing burrows.
When the Hutton’s shearwater was rediscovered by Trustee Geoff Harrow in 1964, there were eight colonies but only two survive now – on conservation land in the headwaters of the Kowhai River and on private land in Shearwater Stream.
Huttons Shearwater status Endangered

Migration

Migrates across Tasman Sea to Australia, where some birds apparently move up E coast while others follow S and then W coasts; birds may perform clockwise or anti-clockwise circumnavigation of Australia, although no evidence of extensive passage through Torres Strait

Distribution map

Huttons Shearwater distribution range map

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