New Zealand Antarctic research programme

Since parameters of penguin populations may provide good indices of the abundance of the key prey species (krill) and thus the state of the Antarctic marine ecosystem, aerial reconnaissance and photography are used in the Ross Sea sector of Antarctica to determine where Adelie penguins (Pygoscelis adeliae) breed, and to count the numbers of nests occupied during the early incubation period and surviving chicks in mid-January (when weight and measurements of samples of chicks at Capes Royds and Crozier give a condition index). From 1981 to present, all islands and sea coasts between 158°E and 175°E were searched, and 12 previously unreported breeding rookeries were discovered. Thirty-nine Adelie rookeries are now known from the region, with a total of about 1,082,000 breeding pairs - almost half the world population. Some rookeries are photographed in all, or most, of the seasons to study the pattern of natural population fluctuations. Populations at nearly all rookeries have increased markedly in size over the last 10 years. Possible reasons for this, and for annual fluctuations in numbers breeding, include seasonal variations in sea ice and weather conditions, and longer-term climatic change. This study identifies the need for complementary Ross Sea baseline studies including: studies of primary productivity and effects of ice thickness and UV radiation, climate change, krill distribution and abundance, seasonal distribution of sea ice, air temperature at sites remote from continental influence, and satellite tracking of radio-tagged penguins to study foraging range and winter dispersion.
In 1992/93 we propose repeating the photographic surveys of rookeries on Ross Island using helicopters in December and January to count incubating adults and surviving chicks, respectively. Rookeries north of Ross Island will be photographed from an RNZAF C-130 in December. Details of methods and logistics are discussed.
In New Zealand, developing, printing, collating, filing and counting all photographs of study rookeries is completed each season.