Seagull Rookery Close To Auckland

Press, Volume XCVIII, Issue 28821, 16 February 1959, Page 9

Seagull Rookery Close To Auckland

*Tn» Press' Special Service

AUCKLAND, February 15. Four miles from Queen street. Auckland, lies New Zealand’s largest seagull rookery. Yet only a few Aucklanders know about it. Behind -the Rdngitoto Beacon, along two stony beaches, and about half a mile inland on to a great field of jagged, crumbly scoria, some 4000 black-backed gulls have settled. The colony, handy to the stretch of sea where a launch daily empties Auckland waterfront garbage, has an almost ideal place for nesting. Isolated and hidden, ,the lava field is near fishing grounds and shell-fish beaches and is one of the warmest places in the Hauraki Gulf. This is not the only colony on the island. Three or four others have been formed on similar scoria fields, although they are still small. Gulls are by nature gregarious but several have been found in nests miles from other colonies. Residents on the island believe a few gannets may be nesting on the island, although no-one is sure where the rookery is. Young Caspian terns have been seen feeding around the Rangitoto coastline but there is no proof that the birds nest there. Normally they settle on remote shingle beds and deserted beaches. x In early November, the blackbacked gulls leave the harbour and Auckland beaches where they have wintered and fly to Rangitoto. It is not known how long the colony has been there but it is certain that it has grown with Auckland and will probably continue to grow. At the nesting grounds the birds generally make for the shallow depressions and basins in the rocks and, cushioning the nests with a few droppings, feathers and bits of weed, lay their eggs. Each female usually lays two or three eggs, which are yellowgrey. blotched with grey and dark brown. By December, the chicks are hatched, and late that month they see their first human. For the last eight years, each December, Mr J. C. Davenport, a member of the Ornithological Society, has visited the rookery to ring the fluffy brown fledglings. Last December he banded about 1100 birds. Each ring bears a serial number and a direction to the finder to send the bird to the Auckland War Memorial Museum. Any tagged seagull found dead is welcome to Mr Davenport, because he cdn then study the growth, distribution and health of the gulls. Difficult First Year The first year of a gull’s * life is his most difficult. If the eggs survive marauding neighbours, then the chicks often do not, although the parent birds savagely protect their young. Two grown gulls have been known to beat off a harrier hawk, and regular visitors to rookeries know well the birds’ alarm systems. As a visitor approaches to within about half a mile of the colony, one or two gulls hover overhead. If he goes closer they begin to mew. Soon five, six, 10, 20, or 100 birds are wheeling and swooping

overhead. As the visitor reaches the colony, the entire body rises up, with a great shrill scream. Some of the older, stronger gulls—the bullies of the colony—have attacked visitors, although usually they fly straight at a visitor’s head, before climbing directly over him. When the bird leaves the nest its troubles have just begun. Mr Davenport believes that some disease is killing many of the young gulls. It is normal for the inexperienced birds to be bullied and robbed of food by older gulls. Death by Misadventure Seagulls have been found drowned in milk vats, caught fast in glue deposits in freezing works, run over by cars, snagged by fishing lines and killed by dogs. One was run down by a train, not a few have been choked with oil slick on the harbour, and one was found in a lion’s cage at the Auckland zoo.

Mr Davenport, from his study of the birds, believes that the life span of the bird is about 10 years, but that most die by accident. In its first year, the gull remains a patchy brown and in the next three years slowly changes to the black and white of the mature bird.

The scavenging seagulls have no regular migrating habits. As a rule they stay round the one colony, although Rangitoto birds have been found aS far south as Wellington and as far north as Leigh.

"Some people say that the birds should be left alone,” said Mr Davenport, defending the practice of tagging the gulls. "But the birds, great scavengers, fill an ecological niche in the scale of animal relationships, and we should learn more about them."