 |
Barrett RT, Nilsen EB, Anker-Nilssen T
Long-term decline in egg size of Atlantic puffins Fratercula arctica is related to changes in forage fish stocks and climate conditions
Egg production is costly for female birds and egg size varies in response to the amount of energy invested in the eggs. Barrett and colleagues found a significant decline over 30 years in the mean volume of Atlantic puffin Fratercula arctica eggs in two Norwegian colonies, a decline unprecedented among auks (Alcidae). Notable was the fact that the colonies were widely separated, in different ecoregions, differed greatly in size and of contrasting population status. Furthermore, the size of adults did not decrease. Statistical modelling demonstrated that the declines were driven by inter-annual changes in abundances of important prey species. The declines were also influenced by climatic variables suggesting other prey may have played a role. A decline in egg size may have negative effects on puffin populations.
Inter-Research Science Publisher is pleased to make this Feature Article openly available for viewing by our readers.
