Processes influencing the population dynamics and conservation of African penguins on Dyer Island, South Africa

摘要: Dyer Island, South Africa, supported the largest African penguin Spheniscus demersus colony in 1979 (22 655 breeding pairs), but population dynamics of species have not followed trends adjacent colonies years high fish abundance or shifts prey distribution. Less than 1 500 pairs were on Island 2013. Available knowledge demographic parameters was collated and ecological processes quantified. Juvenile adult survival probabilities estimated for birds ringed between 2005 2011 0.247 (SE 0.06) 0.545 0.05) respectively. Juveniles had a probability (0.918; SE 0.077) moving away from Island. Predation by seals kelp gulls, as well oiling, are currently important top-down pressures penguins Numbers island negatively correlated with purse-seine catches 20 nautical miles around it. However, it seems that once size is <3 pairs, importance fi...