Saturday, June 15, 2013

CAMPBELL ISLAND: BIRDING DOWN UNDER VOYAGE

Campbell Island, New Zealand's southernmost subantarctic territory is as rich and diverse as the other islands. We shall spend DAY 10 of the Birding Down Under Voyage at Perseverance Bay, exploring a myriad of wildlife.

A world center for albatross diversity, the Campbell Islands host more species than any other subantarctic group except Crozet in the southern Indian Ocean. At Campbell six species are breeding and one of the six breeds nowhere else, the Campbell mollymawk, pictured below. An estimated 26,000 pairs of Campbell Albatrosses breed. They nest on the northern part of the main island, either in their own colonies, or mixed with the Grey-headed Albatross which is circumpolar. The Campbell mollymawk is distinguished  from the similar looking Black-browed Albatross, another species that breeds here in low numbers, by its honey-colored iris, a bolder black eyebrow and a bill of slightly different color and shape.
The Light-mantled Sooty Albatross, below, typically nests on rocky cliff ledges and other steep places.
Two great albatrosses nest at Campbell: the Southern Royal Albatross, below, and in very low numbers, the Antipodean Albatross. Campbell Island is the Southern Royal's main breeding ground. An estimated 14,000 pairs breed here.
Campbell Island is also the main breeding ground for the Yellow-eyed Penguin, a New Zealand endemic and one of the world's rarest penguins. Large numbers of White-chinned Petrels and Sooty Shearwaters breed here, along with Northern Giant Petrels, Diving Petrel and Grey-backed Storm-Petrel. The New Zealand Antarctic Tern has its stronghold here. It is a rare subspecies (possible species?) restricted to the New Zealand subantarctic islands and Stewart Island. Brown Skua also nests here.
Grassland covers much of the island, but megaherbs, above, occur from sea level to the summit ridges.
Three land birds occur here: a teal, above, a snipe and New Zealand pipit. The snipe was discovered in 1997 on Jacquemart Island. The flightless Campbell Island Teal, one of the world's rarest ducks was rediscovered on Dent Island, off Northwest Bay in 1975. Related to the Auckland Island Teal and endangered Brown Teal of mainland New Zealand, it feeds mainly on aquatic or marine invertebrates.

Among the marine mammals, seals are well represented at Campbell Island. There are populations of New Zealand Sea Lion, New Zealand Fur Seal and Southern Elephant Seal.

The removal of sheep and cattle changed the island. But it was the rat eradication program that really brought the island back, including the megaherbs. This is one of the most sensational stories in seabird conservation. The New Zealanders went on to become worldwide experts in the eradication of rats from islands. They are currently working to remove rats from South Georgia, another one of the world's most spectacular subantarctic islands.
We depart for the Antipodes Islands at day's end and spend DAY 11 at sea.
Debi Shearwater


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