Population dynamics of land bird populations on Oahu, Hawaii: fifty years of introductions and competition

Abstract

Data from the annual Christmas Bird Count between 1939 and 1989, around Honolulu, on the island of Oahu during late December, were analyzed to discover the annual rates of change and possible competitive interactions of introduced and native land bird species. Both total number of species and total number of individuals increased over the period. The proportion of species that were rare dropped, rose, and dropped again during the 50-year period, probably as a result of new introductions. Two species held steady, while 12 increased (about 9 linearly and 3 logarithmically). The higher rates of increase were 10-25% per year. Six species declined, but no well-established species became extinct. Negative correlations between population sizes indicated possible competition between the Japanese White-eye Zosterops japonicus and the native Apapane Himatione sanguinea and Elepaio Chasiempis sandwichensis, and between the Red-billed Leiothrix Leiothrix lutea and White-rumped Shama Copsychus malabaricus.

Citation

Ralph, C. John. 1991. Population dynamics of land bird populations on Oahu, Hawaii: fifty years of introductions and competition. Acta XX Congressus Internationalis Ornithologici, Christchurch, New Zealand 2-9 December 1990. 3:1444-1457