High predation rates by pumas on Magellanic Penguin adults: New conflicts in coastal protected areas in Argentina

ESTEBAN FRERE; ANA MILLONES; ANNICK MORGENTHALER; ALEJANDRO TRAVAINI; PATRICIA GANDINI

Vancouver

Conferencia; I World Seabird Conference; 2010

Avian predation on Magellanic penguin along theArgentinean coast was historically reported. However,carnivore predators never represented an important mortalityfactor. Monte Leon National Park was created in 2004, whereovine cattle were excluded. Since 2004 we monitored itscolony and from 2007 we are evaluating carnivore predationimpact on adult penguins on six 2500 m2 plots along the colony, where number of breeding pairs, adults predated, sex,timing, and location of carcasses were recorded. Predatorspecies was identified by carcass necropsy. We have alsoinstalled four camera traps to identify and quantifyresponsible individuals. High levels of mortality weredetected from 2006; over 95% of the adults were predated bypumas. Most penguin carcasses were actually not consumed.At the studied plots, between 2007 and 2008 nest densitydecreased by 47% (F=10.42; p<.0017). The highest predationrates were observed in two plots (X22007=435, X22008=445,p< 0.001) located at the periphery and near to ravines. During2007, 15% and 5% of the breeding adults were predated atthose plots and the same figures, during 2008, were 36% and19%. Our preliminary estimation showed that more than 1500adults are killed each year. Preliminary camera analysesidentified an adult puma with three young as the formerpredators. Removal of those individuals seems the betteroption as a management tool, in order to stop the decrease(16%) of the penguin colony observed during the last years