Attachment

Download

The size of the sooty shearwater (Puffinus griseus) population at the Snares Islands was estimated by counting burrows in the main vegetation types. Some 3,287,000 burrows were calculated for Main Island, the highest densities being 1.9/m2 in Poa meadows, with 1.2/m2 under the trees of the Olearia forest. Most burrows were occupied but data on rates of occupation by breeding birds were not satisfactory. Assuming a 75% occupancy rate. we get a total population of about 2,750,000 burrow-holding pairs on the 328 ha of the two largest islands.