<p>Survivorship among Adelie penguins is lower in individuals who begin to breed at younger ages, between 3 and 5 years. However, individuals that do attempt to breed at an earlier age tend to breed more successfully in later years than penguins that first breed at 5 to 6 years old. Adelie penguins have been known to live as long as 16 years.<span> (Ainley, 2002)</span></p>
- Ainley, D. 2002. The Adelie Penguin: Bellwether of Climate Change. New York: Columbia University Press.