INVESTIGADORES
PALACIOS Maria Gabriela
artículos
Título:
Physiological differences between two overlapped breeding Antarctic penguins in a global change perspective
Autor/es:
D´AMICO, V.; CORIA, N.; PALACIOS, M. G.; BARBOSA, A.; BERTELLOTTI, M.
Revista:
POLAR BIOLOGY
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2014
ISSN:
0722-4060
Resumen:
Global change has affected theAntarctic Peninsula influencing the abundance of krill, one of the main preysof penguins. In areas where breeding penguin populations overlap, species witha more diverse diet have generally been less affected than krill-specialistspecies, which have shown population declines. Human activities can add tothese changes, as penguins are sensitive to anthropic impacts such ascontamination. Our objective was to assess whether selected physiologicalparameters of Adelie and Gentoo penguins reflect their contrasting population trendsin a colony located at Punta Stranger (25 de Mayo Island/King George, SouthShetland Islands) where they breed sympatrically. During 2012, we assessed the leukocyteprofile, heterophil to lymphocyte ratio (H/L), erythrocytic nuclearabnormalities (ENAs), hematocrit, biochemical profile, and a measure of immunefunction (bacterial agglutination) in adults and chicks of both species. Highervalues of ENAs, indicative of genotoxic damage caused by contaminants, are inaccordance with a greater sensitivity to ongoing global changes by Adelie penguins.Levels of cholesterol and triglycerides strengthen this idea since individualscould be investing more resources in energy reserves to successfully cope with challengingenvironmental conditions during the breeding season. The remainingphysiological parameters did not provide a clear picture. Furthermore, someresults could be related to differences in diet. Gentoos show greater prey diversitythan Adelie penguins, incorporating a richer parasite fauna, which couldexplain their higher heterophils and H/L. The physiological parameters measuredhere serve as baseline for a sustained monitoring of these rapidly changingpopulations. Further physiological variables, including stress hormone andindices of oxidative stress, remain to be assessed as potential indicators ofpopulation susceptibility to global change in this system.