Distribution of sooty shearwater (Puffinus griseus) breeding colonies along the Otago Coast, New Zealand, with indication of countrywide population trends

Large breeding colonies of Sooty Shearwaters or Titi (Puffinus griseus) occur on offshore islands around New Zealand and several smaller colonies occur on headlands and near-shore islands around southern New Zealand; their population trends are unknown. Twelve mainland colonies around Otago had between 11 and 620 burrows in the 1992/93 breeding season. The largest of three near-shore island colonies in Otago had at least 1,050 burrows. Sooty Shearwater burrows have been recorded from 39 mainland sites in the South Island, but only 11 (28%) of these have been checked in the last 40 years: many may now be extinct. OSNZ Beach Patrol data suggest that the overall number of Sooty Shearwaters has changed little over a 26 year period. Methods for monitoring Sooty Shearwater colonies need to be standardised to evaluate population trends in the future.