The high Arctic is changing rapidly: climate change means advancing springs, and more treacherous winters, with more frequent extreme weather events. On top of this, barnacle geese breeding in the Arctic have been on a diet. So many geese are now migrating to northern breeding grounds that in some places there’s less food to go around. The good news is that it doesn’t seem to restrict their population growth — yet.
This study of individuals’ physical condition, over almost 30 years, showed a 10% decline in average body condition. Especially for herbivores, reduced condition should lead to reduce reproduction and survival. Surprisingly, however, this decline didn’t translate into noticeable effects on population numbers. This is because it’s overridden by other important environmental effects, such as positive impacts of earlier springs and negative effects of Arctic foxes on reproduction. Nevertheless, there is obviously a limit to how skinny the geese can be, if their summer habitat continues to degrade, so it’s likely to restrict population growth at some point in the future.
You can find the full paper here.
Reference: Layton‐Matthews, K., Grøtan, V., Hansen, B.B., Loonen, M.J., Fuglei, E. and Childs, D.Z., 2020. Environmental change reduces body condition, but not population growth, in a high‐arctic herbivore. Ecology Letters. doi: 10.1111/ele.13634
Link to full article write up: https://norwegianscitechnews.com/2020/12/skinnier-but-resilient-geese-thriving-in-the-high-arctic/
Text: Kate Layton-Matthews, Norwegian Institute for Nature Research
Photograph: Svalbard barnacle geese (Branta leucopsis) (photo credit Jasper Doest Photography)