While the Arctic contains many resources, they are spread over a wide area – there is not enough food available in the tundra to feed many individuals in one place. Sometimes, therefore, it is necessary for individuals to move from one area to another in order to maximize the amount of food they or their offspring can obtain.

Many geese and ducks in the Arctic perform "moult migrations" – special midsummer journeys to areas outside the breeding grounds. As soon as incubation begins and there are no more breeding opportunities, males and non-breeding individuals leave the nesting grounds. They fly to an area, often further north, which is rich in food and isolated from predators. Lake Hazen, Ellesmere Island, is one such destination. The food supply in these moulting areas, although rich, may not last long enough for birds to breed there successfully. However, for a few weeks, they are ideal places for male birds to gain the nutrients – especially protein – needed to grow new feathers, and to prepare for the fall migration. By moving away to feed and moult, males leave more food for their mates and offspring – like raiding the neighbour's fridge while saving the food at home for your family.