Conservation of the endangered New Zealand fairy tern

Abstract

The New Zealand fairy tern Sterna nereis davisae has only one small population of c.30 individuals and its conservation is a priority. The population was declining prior to the mid 1980s. Management of the three remaining breeding sites was initiated during 1983/84 and intensified from 1991 onwards. We have collated historic data and reviewed the changes in the population since 1991. Our results illustrate that the number of chicks fledged increased since 1991. Fifty-five chicks fledged between 1991/92 and 2002/03. Demographic modelling based on productivity and age-specific survival estimates predicted that the population should increase at c.1.5% per annum. The predicted results from the demographic model contrasted against the observation of a stable resident population. This difference could have resulted from the movement of individuals out of our study area. Demographic modelling also indicated that the population may have continued to decline at a rate of c.1.4% per annum if management was not initiated. Extinction risk within 50 years has decreased from 0.52 to 0.39.