Ecosystem Functioning

Adélie penguin population dynamics

Principal Investigator: Phil Lyver
Organisation: Landcare Research Ltd

What we do: This collaborative project (joint NZ/US) addresses the theoretical question "What mechanisms control population size and colony distribution of Adélie penguins (Pygoscelis adeliae)?". The project distinguishes the relative importance of key resources (nesting space and food) that constrain growth of colonies, and examine behavioural (immigration/emigration and breeding effort/success) mechanisms that may influence colony size.

Why we do it: The results of this study help is to understand the impact of climate change and human impacts (fisheries, tourism, pollution) on the Antarctic marine ecosystem.

Some things we've found out: Due to the heavy sea ice conditions that have existed in the McMurdo Sound area since 1999 and the presence of large icebergs, Cape Bird penguins trying to raise chicks have had a hard time. They've had to walk further to get to their chicks, and the chicks have been lighter and fewer than pre-1999 figures. At the more northerly Cape Hallett colony where 'normal' sea sea conditions prevail, the average chick weight was greater than at Cape Bird.

Recent Publications:
Ainley, D.G. et al. Decedal-scale changes in the climate and biota of the Pacific sector of the Southern Ocean, 1950s to the 1990s. Antarctic Science 17(2): 171-182. 2005. View Abstract.

Ainley, D.G. et al. Geographic structure of Adélie penguin populations: overlap in colony-specific foraging areas. Ecological monographs 74(1): 159-178, 2004. View Abstract.

Ainley, D.G. et al. Spatial and temporal variation of diet within a presumed metapopulation of Adélie penguins. Condor 105: 95-106, 2003. View Abstract.