Post-moult movements of sympatrically breeding Humboldt and Magellanic Penguins in south-central Chile

K PÜTZ; A RAYA REY; L HIRIART BERTRAND; A SIMEONE; R REYES ARRIAGADA; B LÜTHI

Global ecology and conservation

Elsevier

Año: 2016 p. 49 - 58

Ten Humboldt (Spheniscus humboldti) and eight Magellanic Penguins (S. magellanicus) weresuccessfully equipped with satellite transmitters in March 2009 on Islotes Puñihuil incentral south-Chile to follow their post-moult dispersal. Overall, Humboldt Penguins couldbe followed for a mean period of 49 ±18 days (range: 25?93) and Magellanic Penguins for57 ±12 days (range 35?68). Irrespective of species and sex, seven study birds remainedin the vicinity of their breeding ground throughout the transmission period. All otherpenguins moved northwards, either only a relatively short distance (max 400 km) to IslaMocha at 38°S (n = 3) or further north beyond 35°S (n = 8). However, eight of these birds(73%) turned south again towards the end of the individual tracking periods. The total areaused by both species during the tracking period was restricted to a coastal area stretchingfrom the breeding site at 42°S about 1000 km to the north at about 32°S. The area used byHumboldt penguins overlapped by 95% the area used by Magellanic penguins, whereas thearea used by the latter species was much larger and overlapped only by 45% with the areaused by Humboldt penguins. Overall, our results indicate that Magellanic Penguins in thePacific Ocean are probably less migratory than their conspecifics on the Atlantic side, whileHumboldt Penguins appear to be more migratory than previously anticipated. In general,there was a poor relationship between preferred foraging areas and chlorophyll-a, as aproxy for primary productivity, indicating the limitations of using remote-sensed primaryproductivity as a proxy to interpret the foraging behaviour of marine predators. In addition,there was also no clear relationship between the preferred foraging areas and the amountof regional fish catches by artisanal fishery.