H—22

The work at the existing trapping and banding station in the Manawatu was augmented this year by the addition of two further stations at Lake Waikare, Ohinewai, and at Titri, Lake Waihola. This will give an improved basis for the statistical analysis of hunting losses, longevity, and range of flight. The banding was done by speciallytrained members of the ranging staff, under the supervision of a Field Officer attached to the research section. In the course of these operations, between January and March, over 4,000 ducks were banded. A biologist studied ecological aspects of vegetation in relation to waterfowl while participating in the ecological survey of the Northland lakes conducted by the Freshwater Fisheries Division of the Marine Department. The Wellington Acclimatization Society again gave valuable assistance through the services of its ranger, Mr. T. Andrews. Acknowledgments are also made to the Councils and staffs of the Otago and Auckland Acclimatization Societies for assistance in banding operations. (2) Wallabies No further studies have been possible on the economic significance of these animals. (3) Opossums Further experiments in methods of poisoning opossums were continued in the Poverty Bay area. Surveys on the distribution and incidence of this pest were continued in the central and southern portions of the North Island, Wanganui, Auckland, Blenheim, and Canterbury districts. To fulfil the need of educating the public in regard to the damage done by this animal, articles containing suitable methods of trapping which were published during the year in the Journal of Agriculture, were reprinted in bulletin form and widely distributed to interested persons. Many additional inquiries for this information have been received. When the survey has been completed it is intended to institute a campaign throughout the country against this pest in an effort to regain control. (4) Deer An ecological survey on the habits of deer in the Kaimanawa Ranges has been carried out. A report is in course of preparation and will soon be ready for release. Further work of a similar nature is being pursued in the Southern Tararuas. (5) Native Birds Surveys have been made of island sanctuaries with the object of finding suitable Refuges for species of rare birds. This work is in continuance of that instituted in the previous year. Parties were organized to visit the habitat of the takahe (Notornis) to conduct fundamental research into the little-known habits of the species. Prominent ornithologists were invited to participate. Evidence of a camp of moa hunters was discovered by Mr. K. Miers, an officer of the Department. Authority was granted to ethnologists to study the moa remains and much valuable historic data has accrued. (6) Fisheries (Rotorua and Southern Lakes Acclimatization Districts) Details of eel-trapping operations in the Southern Lakes District were made available by the Senior Fisheries Officer of the Marine Department. He proposed that eels should be trapped, at varying depths with nets and hand-lines to provide further data for the assessment of eel populations and the effectiveness of trapping programmes. He remarked that it would be useful to have information regarding the size of eels in Lake Wakatipu. These suggestions are being carried out.

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