Update of the population size and breeding performance of Gentoo penguins (Pygoscelis papua) at Stranger Point/Cabo Funes, South Shetland Islands

JUÁRES M.; CASAUX R.; NEGRETE J.; RIOS, A.; CASTILLO M.; CORIA N.; SANTOS M.

POLAR BIOLOGY

SPRINGER

Lugar: Berlin; Año: 2020 vol. 43 p. 123 - 129

0722-4060

AbstractThe plasticity in the trophic ecology, the breeding phenology, and the low nesting site fidelity would be the reasons why mostof the gentoo penguin (Pygoscelis papua) populations breeding in the western Antarctic Peninsula and islands of Scotia Arcremained stable or increasing, despite the changing environmental conditions. Regardless of the overall trend, recent studiesrevealed a decline in the abundance of some gentoo penguin populations at those regions. Therefore, it is highly valuable toupdate the population size of each colony in order to confirm the current trends of individual colonies and generate a comprehensiveoverview of the population status. We report the abundance and breeding performance of gentoo penguins at theStranger Point/Cabo Funes colony from 2000/2001 to 2018/2019. During the last season, 5383 breeding pairs and 5545 chicksin crèche were counted. Despite there were considerable inter-annual fluctuations over the study period, the total number ofgentoo penguin breeding pairs increased by 74.6% (+ 3.1% per annum), while the number of chicks crèched increased by60.0% (+ 2.6% per annum). However, the index of breeding success remained relatively constant over time, varying between0.74 and 1.23 chicks in crèche/breeding pairs. Gentoo penguins have life-history strategies that are advantageous to face theenvironmental variability, allowing the species to maintain their breeding performance stable over time and enhance theirresilience, which can favour the population growth at Stranger Point.