Antipodean wandering albatross Diomedea antipodensis antipodensis breed almost exclusively on Antipodes Island and following a dramatic population crash in 2006, males have been declining at about 6% per annum and females at about 12% per annum. The decline appears to be driven mainly by high female mortality, with a marked sex imbalance now conspicuous in the breeding population.
There is a significant negative relationship between La Nina conditions (which bring warmer sea temperatures to the western Pacific) and the survival of breeding female Antipodean wandering albatrosses. However, while breeding success dropped from a mean 74% prior to the crash to 60% after it, poor nutrition of breeding females in La Nina summers appears unlikely to be the proximate cause of their high mortality as birds usually abandon breeding if their condition is too poor. The main preventable cause of high female mortality is likely to be fisheries bycatch north of New Zealand and in the central and eastern Pacific between 20-35°S, occurring in late winter and spring.
Antipodean wandering albatross are now assessed by the New Zealand Threat Classification System as “Nationally Critical” (Robertson et al 2017) and understanding the causes of and solutions to the high female mortality is urgently required. Extensive real-time satellite tracking should be used to better define problems the birds are encountering at sea.
Elliot, G. & Walker K. (2018). Antipodean wandering albatross census and population study 2018. Prepared by Albatross Research, 18 p.