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Southern fur seals Arctocephalus australis in Peru have declined gradually over the past decade, and declined dramatically (72%) as a result of low food availability during the severe El Niño in 1997–98. In 1999, seals abandoned some historically important breeding sites. This is particularly alarming because new sites were not colonized. Our objective was to examine how habitat features and human disturbance influenced whether sites were currently used, abandoned or apparently not used in the past by fur seals for breeding. Data were collected on 14 variables at 70 potential breeding sites at three guano reserves in Peru. Discriminant analysis revealed significant multivariate differences among sites currently used for breeding, abandoned sites and unused sites (F=5.97, P<0.00001), and the model classified 74% of sites correctly. Currently used sites were less likely to have human disturbance and more likely to have offshore islands, stacked rocks, tide pools and abundant shade. Separate discriminant analyses for each reserve produced similar results. Habitat associated with thermoregulation (e.g. shade or pools) may be more important to fur seals in Peru, which breed at lower latitudes and are at greater risk of overheating on land than other populations. Habitat with minimized human access may be especially important to seals in small populations in which individuals may perceive themselves as more vulnerable because of decreased vigilance and dilution effects. Seals in our study selected breeding habitat with stacked rocks, which create shade and tide pools for thermoregulation and make human access difficult; but pups might suffer higher mortality in this habitat. We hypothesize that fur seals in Peru may exhibit an Allee effect, whereby suitability of habitat varies with population abundance. [ABSTRACT FROM AUTHOR]

This study investigates the foraging behaviour of endangered Humboldt penguins (Spheniscus humboldti) to examine general foraging patterns, sex differences in foraging behaviour, and the reasons for incidental catches in fishing nets. To date, the only information on foraging patterns of Humboldt penguins comes from Chile. Results from the study site, Punta San Juan, Peru, suggests that 922 of approximately 4000 breeding Humboldt penguins died in fishing nets between 1991 and 1998. We report means plus or minus 1 standard deviation (SD) and set significance at a 0.05. The foraging behaviour of Humboldt penguins at Punta San Juan from May to November 1999 was studied by deploying Mark 7 time-depth recorder.