J. McDaniel and S. Emslie; Department of Biological Sciences

University of North Carolina at Wilmington; Wilmington, NC 28403 USA


This study examined the effects of climate change on the diet of Adelie penguins in the Antarctic Peninsula through systematic excavations at both abandoned and modern breeding colonies. Previous studies have shown that Adelie penguins rely heavily on krill as a staple component of their diet (Ainley et al. 1984). However, recent studies have suggested that mesopelagic squid (Psychroteuthis glacialis) and two Antarctic fish (Pleuragramma antarcticum and Electrona antarctica}also are important prey items of Adelie penguins. In addition, proportions of these prey items appear to vary with climate change (Emslie et al. 1998). This study compared dietary remains preserved within the sediments of both abandoned and modern Adelie penguins colonies in the Antarctic Peninsula. Antarctic silverfish and squid were the two most abundant prey species found at these sites. After correcting for the volume of sediment excavated, the Minimum Number of Individuals (MNI) of Pleuragramma antarcticum varied significantly between sites of different ages (X2, df = 6, p<.001), but Psychroteuthis glacialis did not (X2, df = 6, p>.25). The overall trend suggested that Pleuragramma antarcticum was consumed more during colder climatic periods than during warm periods. This trend could be an artifact of small sample size or a result of poor preservation within the sediments. However, since the younger sites displayed evidence of a higher MNI, it would be advantageous to collect additional samples to examine this trend more thoroughly.

Click to enlarge photos below!

Adelie Penguin Colony on Devil Island

Study Areas

Click here to view Introduction