Canada goose reduction an important success

Press, 3 May 1977, Page 17

Canada goose reduction an important success

The South Island population of Canada geese has been halved in the last four years from about 22,000 to about 10,000, and the population may sink as low as 7000 by their next breeding season in the spring. This reduction in population is the major, and intended, result of the alteration of the bird’s status in 1973 to a game bird. The reduction is largely the result of highcountry runholder pressure on the Wildlife Service to reduce numbers, but also owes something to the wish to be able to manage the bird elsewhere in New Zealand.

Canada geese were first introduced to and liberated in New Zealand in the early 1900 s. They did particularly well in Canterbury province, and also in the Hawea, West Wanaka and Hunter Valley areas. The absence of hunting pressure during the Second World War contributed to the rapid build-up in numbers • during the 19405, and their isolation in their favoured habitats in the South Island high country also helped. Control measures became necessary.

Systematic nest and egg destruction began in the late 19405, accompanied b the shooting of nesting and breeding geese in the main areas.

So effective was this campaign that in a number of breeding areas in the high country — the headwaters of the Hurunui, for example — numbers still have not recovered to their original levels.

The high-country runholders took stern measures. They organised moult drives, flapper drives, used aircraft, and generally exerted considerable control over Canada goose numbers. Flapper drives became a tradition in some areas and the fact that the large but still flightless goslings were ready just after Christmas but in time for the New Year -made it a social occasion. It was in North Canter-

bury that the potential of Canada geese as “game” was first recognised. In 1963 the North Canterbury Acclimatisation Society declared geese to be “game” east of the main trunk railway line, with a special hunting season from January-March. This had a major effect on goose numbers around Lake Ellesmere where as many as 6000 birds may have been killed in the first season. Whereas total mortality had previously been less than 20 per cent, this rose to 40-50 per cent in the first season, although dropping later.

For some years it has been the policy of the Wildlife Service that Canada geese be recognised as game. In 1973, the

Wildlife Service reached agreement with the highcountry sub-section of Federated Farmers that geese be considered game nation-wide.

There was some public pressure for this because of concern at the methods being used to kill Canada geese, as well as concern over the numbers of endemic paradise ducks being killed during geese moult and flapper drives.

The major terms of the 1973 agreement were that the geese be declared game for a trial period of three years, that the season last most of the year with unrestricted hours (except the nesting-moulting period from October-late January, and April to pro-

vide a quiet period before the duck season proper), that there v)ould be ready help from acclimatisation society staff where farmers had problems and the right to destroy or disturb any geese at any time of the year by any landowner on request, and an assurance that where numbers were getting out of hand the Wildlife Service would assume full responsibility for control.

One major result of the agreement was to give the Canada goose protection in areas where ft had not previously been notified as game — particularly in the North Island where several acclimatisation societies wanted it established.

The trial ran for three years, but a further year was added and this is now nearly up. Apart from a few areas, the Wildlife Service says it has been successful beyond anyone’s wildest dreams, Even in areas where runholders say there are still too many, numbers are well down, and a recent bird count in the Omarama district (for example) showed numbers to be below 900. A review of the trial in 1976 led to Canada goose production being limited by egg pricking in some areas, the extension of the game season to include the full months of October and March, and further thought to assessing

“acceptable population levels” in individual areas.

What is “acceptable” is still being discussed. Control is largely by egg-pricking and shooting. Six parties of two men each in the spring of 1976 covered the East Coast South Island rivers from the Wairau to the the Hunter and pricked every egg in the nest except one — so the goose would not build another nest.

About 80 per cent of goose nests were done and 1675 eggs pricked, and the Wildlife Service estimates that there are 1000 fewer flying birds in Canterbury as a result. The programme will be repeated this year. This last season about 2000 geese were shot on

Lake Ellesmere and another 380 at Omarama, apart from smaller numbers elsewhere. However, another 280odd were caught and later liberated in Auckland. Southland and Taranaki. The introduction of a season has meant that Canada geese can now be liberated safely in other areas like Auckland, Gisborne, Wairoa, Taranaki and Southland without them being shot. Many farmers, particularly in the Waikato, are vehemently opposed to their liberation, but in other areas they have been sought for breeding so a game flock can be established.

Canada geese are very shy birds and very easily

disturbed. They nest in open, cleared, spaces so they can see danger, and are easily frightened from a particular paddock or open space by a gun fired over their heads or by a loud noise. The Wildlife Service is not keen to see numbers fall too low. It considers that by creating a game bird situation it has controlled numbers in a way that the flapper drives and public slaughter in the past quite failed to do, which should satisfy runholders who consider the Canada goose competes for grazing.

But it also considers that if numbers fall ton low then large tracts of country will be without a desirable game bird.