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B. Field Investigations and Research (1) Waterfoivl The biologist assigned to this work was absent 011 special leave for purposes of study for several months. During the remaining period, work continued in the Manawatu area as under : (a) One thousand wild ducks were trapped and after being sexed and aged were banded and released. Over 22 per cent, of the 570 grey and mallard ducks banded the previous year were accounted for as the result of excellent co-operation bv sportsmen in returning the bands. (b) An ecological survey of local lakes was carried out in conjunction with the Botany Division, Department of Scientific and Industrial Research. (c) Two field parties assembled data from shooters' bags during the opening days of the game season. The Wellington Acclimatization Society again gave invaluable assistance through I;he services of its ranger, Mr. T. Andrews. A report on the results to date is in preparation with a view to publication. (2) Wallabies A field survey was conducted over a wider area of the Hunter's Hills, South Canterbury. Sufficient data was recorded as to their significance in respect of soil erosion for the publication of a short paper. (3) Opossums Satisfactory methods of preparing poison baits in bulk for use by control parties were evolved in co-operation with the Dominion Laboratory. A survey of the distribution and significance, of the opossum has continued. Mount Egmont, the south Taranaki and Wellington provinces, the Poverty Bay Catchment District, and Stewart and Codfish Islands have now been covered. An ecological paper on the effect of the opossum on the indigenous vegetation was presented at the Seventh Pacific Science Congress. A further paper, mainly on reproduction, is in preparation. Arrangements were completed to ensure wide coverage by the early publication in the Journal of Agriculture of the material prepared as a wild-life bulletin on the opossum, prior to its issue in bulletin form. (4) DeerSurveys were made in the Tararua Mountains as follows : (а) Southern Portion : Preliminary work in the assessment of deer-population density by a browse survey method. (б) Higher Watershed of the Ruamahanga River: An illustrated report on the relation of deer and other wildlife to this catchment was supplied to a committee studying the control of this river. (5) Native Birds Surveys of certain island sanctuaries to serve as possible refuges for some of the rarer species were made. Research into the habits of the takahe was initiated by an expedition led by Dr. R. A. Falla and including members of the staff. Signs of a further colony of the birds have since been found in a valley near to the. scene of the original discovery. Further research and surveys are planned.

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