| Summary: | Progress Code: completed Statement: All Royal penguin colonies on Macquarie Island have been surveyed, and the method used judged as the most effective method of estimating the total abundance. Two methods were used for the survey depending on the terrain on which a colony was established. Method 1 (Ground survey method): In topographically regular areas, the area of the colony was surveyed during the winter when birds were absent. The colonies were viewed again in the following spring, when penguins were on their nests, in order to check for any major discrepancies between the area surveyed and that occupied by nests. The nest densities were obtained from two 10m by 10m plots staked out in the lower Sandy Bay colony. The plots were photographed in early November when only females were present at the nests and few failures would have occurred. Enlarged photographs of each plot was divided into four 5m by 5m sections and nest counts were made in each of them to obtain the mean number of nests per square metre and the standard deviation. The mean number of nests in the lower Sandy Bay plots was 2.43/m^2 (range at 95% confidence limits 2.32-2.54). In a few cases where pairs were evident they were counted as one nest. Areas within colonies with badly drained ground or large boulders were estimated separately with a slightly lower nest density per square metre. The number of nests was estimated by multiplying the mean nest density by the area of each colony. The range in the number of nests is given by 95% confidence limits of +/-2SE of the mean density. Method 2 (Estimates): The colonies on irregular sites (most of the west coast colonies) were visited in spring or early summer when birds were present. Upper and lower estimates of the number of breeding pairs were made. Breeding penguins were allocated to one of 57 colonies identified by location. Where two or more colonies were in the same general area each was recorded separately. Small groups of birds in close proximity to larger colonies (less that 250m away) ...
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