A comprehensive assessment of mercury exposure in penguin populations throughout the Southern Hemisphere: Using trophic calculations to identify sources of population-level variation

R BRASSO; A CHIARADIA; M POLITO; A RAYA REY; S EMSLIE

MARINE POLLUTION BULLETIN

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2015 p. 408 - 418

0025-326X

The wide geographic distribution of penguins (Order Sphenisciformes) throughout the SouthernHemisphere provided a unique opportunity to use a single taxonomic group as biomonitors of mercuryamong geographically distinct marine ecosystems. Mercury concentrations were compared among tenspecies of penguins representing 26 geographically distinct breeding populations. Mercury concentrationswere relatively low (62.00 ppm) in feathers from 18/26 populations considered. Population-leveldifferences in trophic level explained variation in mercury concentrations among Little, King, andGentoo penguin populations. However, Southern Rockhopper and Magellanic penguins breeding onStaten Island, Tierra del Fuego, had the highest mercury concentrations relative to their conspecificsdespite foraging at a lower trophic level. The concurrent use of stable isotope and mercury data allowedus to document penguin populations at the greatest risk of exposure to harmful concentrations of mercuryas a result of foraging at a high trophic level or in geographic ?hot spots? of mercury availability.