How seals risk their lives for food - scientists find out
Normally, seals try to stay away from polar bears. But a new study has found that if there is more food in the danger zone, they are willing to take a risk - even if it might cost them their lives.
Scientists tracked the movements of 26 ringed seals and 39 polar bears in eastern Hudson Bay using GPS sensors and dive data.
In general, the seals tend to avoid areas where predators frequent. In such areas, they move faster and spend less time underwater.
However, behaviour changes if there is more food in the same areas. In this case, the seals dive longer and stay longer even in areas where the risk of encountering a bear remains high.
Details
The scientists attribute this to the "portfolio effect," a strategy in which animals select a wider variety of food sources to increase their chances of survival.
"Seals don't put all the fish in one basket."
Climate change has an additional impact. Melting ice is changing the distribution of fish and narrowing habitat, causing bears to concentrate in the same areas more often. This increases the risk to seals.
As a result, the animals increasingly have to choose between safety and access to a variety of food.
Why it's important
The research is important to:
- ecologists and conservationists
- predicting changes in the Arctic
- developing measures to conserve populations
Scientists note that not only the distribution of animals, but also their behaviour - including their willingness to take risks for food - needs to be taken into account.
Background
It was previously thought that seals primarily avoid predators. However, a new study shows that their behaviour is much more complex and depends on the availability of resources.
Source
The work is published in the journal Ecology Letters.