Climate change improves the breeding chances of migratory geese in the Arctic — but puts mother geese at more risk of death, according to a new study. Warmer conditions at breeding grounds in north-east Canada help light-bellied Brent geese produce more young… But in years when productivity is highest, the death rate among mothers also increases. The researchers believe this happens because mothers use extra energy laying eggs and face more risk from predators while sitting on their nests, which they make on the ground…..in warmer years mothers breed more successfully — so more of them remain sitting on nests or waiting on the ground until their offspring are ready to fly.
Light-bellied Brent geese are shown. Credit: Kendrew Colhoun
“We tend to think of climate change as being all one way, but here we’ve got a population being affected in conflicting ways,” said Dr Ian Cleasby, of the Centre for Ecology and Conservation on the University of Exeter’s Penryn Campus in Cornwall.”This population is sensitive to changes in adult survival, so the increased breeding may not be enough to offset the loss of more adult females….we have to understand how animal populations will respond to the changing climate if we want to make decisions about protecting biodiversity.“…
Ian R. Cleasby, Thomas W. Bodey, Freydis Vigfusdottir, Jenni L. McDonald, Graham McElwaine, Kerry Mackie, Kendrew Colhoun, Stuart Bearhop. Climatic conditions produce contrasting influences on demographic traits in a long distance Arctic migrant. Journal of Animal Ecology, 2016; DOI: 10.1111/1365-2656.12623