CHATHAM ISLANDS WILD LIFE

Press, Volume CI, Issue 29744, 10 February 1962, Page 8

CHATHAM ISLANDS WILD LIFE

Success Of Sanctuary Plan

[From the Department of Internal Affaire} gFFORTS to perpetuate Chatham Islands birdlife and vegetation by making SouthEast Island a reserve, are proving successful. Messrs Brian Bell and lan Hogarth, two officers of the wildlife branch of the Department of Internal Affairs, discovered this late last year when they spent two months on the Chathams making surveys of water fowl and other wildlife.

They also found that the rare Chatham Island yellow-crowned parakeet and the black robin, which are confined to Little Mangere, an islet 2| acres in area and 600 feet high, are not dying out but are maintaining their numbers. A water-fowl survey showed no sign that black swans were resuming breeding in the islands.

The team established that more than half of the species or sub-species of birds native to the Chathams are to be found on South-East Island. Birds now found only on the island were the shore plover, the Chatham Islands snipe, and the rare Chatham Island petrel. Those rare on the main islands but abundant on South-East Island were the Chatham Island tomtit, tui, and warbler. The snipe, once thought to be nearly extinct, is now plentiful on the island.

The original vegetation, greatly reduced while SouthEast Island was used for grazing sheep, is now returning and spreading. It includes the giant forget-me-not, or Chatham Island lily, and Coxella (a relative of speargrass), which are uncommon on the main islands. South-East Island was used for grazing until 1954 when, on a suggestion from the Fauna Protection Advisory Council, it was bought by the Lands and Survey Department and declared a reserve for the preservation of fauna and flora.

The water fowl survey carried out for the wildlife branch by Messrs Bell and

Hogarth indicated that the black swan will not resume breeding in the Chatham Islands for some time yet. Poor condition resulting from lack of feed is believed to be the reason why black swans have not bred in the Chathams during the last three seasons.

The shortage of feed seems to have developed in 1958, when a sudden increase in the swan population made food supplies inadequate and thousands of swans died. It is also thought that lowering the level of the lagoon on the main island, to reduce flooding, also reduced the supply of aquatic plants on which the swans feed. Last Refuge Little Mangere, a small and rugged island, is the last refuge of two rare birds, the Chatham Island yellowcrowned parakeet and the black robin. Its interior is almost inaccessible—when the survey team went there late last year to check on bird life, it needed two and a half-hours to reach the top of the 600foot cliffs surrounding the island.

The Chatham Island yellowcrowned parakeet inhabiting Little Mangere is similar to the yellow-crowned parakeet found on the mainland. Its brilliant colouring includes shades of green, blue and yellow. Formerly it lived also on nearby Mangere Island, and sometimes flew to Pitt Island. Removal of the forest on Mangere has forced it to retreat to Little Mangere, although the birds still visit the larger island at times. The black robin was once found on the main and adjacent islands of the Chatham group. By 1871 it was confined to Mangere and Little Mangere. Cats, which were introduced about the turn of the century to kill off rabbits on Mangere, also wiped out the robins. The species is now entirely confined to Little Mangere. The wildlife officers found that there are now about the same numbers of Chatham Island yellow-crowned parakeets and black robins as there were in 1937, when the last survey was made. It was estimated then that there were at least 100 parakeets and between 20 and 30 pairs of black robins.