Extreme dives by free-ranging emperor penguins
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We examined the incidence of extreme diving in a 3-year overwintering study of emperor penguins Aptenodytes forsteri in East Antarctica. We defined extreme dives as very deep (> 400 m) and/or very long (> 12 min). Of 137364 dives recorded by 93 penguins 264 dives reached depths > 400 m and 48 lasted > 12 min. Most (65%) very long dives occurred in winter (May–August) while 83% of the very deep dives took place in spring (September–November). The two most extreme dives (564 m depth, 21.8 min duration) were separate dives and were performed by different individual penguins. Penguins diving extremely deeply may have done so as part of their foraging strategy whereas penguins diving for very long times may have been forced to do so by changes in the sea-ice conditions.
KeywordsContinental Shelf Dive Depth Dive Duration Emperor Penguin Deep Dive
We gratefully acknowledge the help and support of the three overwintering teams at Mawson Station in 1988, 1993 and 1994. Without their help and support in the field this work would not have been possible. We thank two anonymous referees for their instructive and in depth comments that helped improve the manuscript. This study was part of the Australian Antarctic Division’s scientific program and was approved by the Australian Animal Ethics Committee (Department for the Environment and Heritage).
- Eastman JT (1993) Antarctic fish biology: evolution in a unique environment. Academic Press, San Diego, pp 322Google Scholar
- Kirkwood R, Robertson G (1997) Seasonal change in the foraging ecology of emperor penguins on the Mawson Coast, Antarctica. Mar Ecol Progr Ser 156:205–223Google Scholar
- Kooyman GL, Kooyman TG (1995) Diving behaviour of emperor penguins nurturing chicks at Coulman Island, Antarctica. Condor 97:536–549Google Scholar
- Ponganis PJ, Kooyman GL (2000) Diving physiology of birds: a history of studies on polar species. Comp Biochem Physiol A 126:143–151Google Scholar
- Robertson G, Williams R, Green K, Robertson L (1994) Diet composition of emperor penguin chicks Aptenodytes forsteri at two Mawson Coast colonies, Antarctica. Ibis 136:19–31Google Scholar
- Slip DJ, Hindell MA, Burton HR (1994) Diving behaviour of southern elephant seals from Macquarie Island: an overview. In: Le Boeuf BJ, Laws R (eds) Elephant seals: population ecology, behaviour and physiology. University of California Press, Los Angeles, pp 253–270Google Scholar
- Wienecke B, Robertson G (1997) Foraging space of emperor penguins Aptenodytes forsteri in Antarctic shelf waters in winter. Mar Ecol Prog Ser 159:249–263Google Scholar
- Wildlife Computers (1998) Dive analysis for MKII through MK7 time-depth Recorders. Wildlife Computers Instruction Manual, Redmond, WashingtonGoogle Scholar