Arctic Shorebird Study Suggests Extreme Migration Decreases Predation Risk

White-rumped Sandpiper photo by Tim Bowman from Wikipedia Commons

I was listening to NPR on the way to work this morning (as I always do, being a proud supporter of public radio) and heard of an interesting study on arctic shorebirds, their migration and predation.

Laura McKinnon, a researcher with the University of Quebec at Rimouski, wondered why some shorebirds that breed in the Arctic region make such an extreme migration from their southern wintering grounds.  The White-rumped Sandpiper travels from the Southern tip of South America to the Canadian Arctic to breed, one of the longest animal migrations in the Western Hemisphere.

Laura thought that one explanation for the long distance migration, other than the longer daylight hours available, might be a lower risk of predation farther north.  She tested this theory by placing over 1,500 artificial nests in the shorebirds Canadian breeding grounds and monitoring them for predation.

One of their conclusions was that if a bird flies past the most southern breeding ground to the northernmost site, and additional 2,000 miles north, it can reduce its predation risk by 66%!  That is a huge difference.

Most of the shorebird predation is by the Arctic Fox.

Arctic Fox in Summer Coat photo from Ucumari (Creative Commons)

The major prey of Arctic Foxes is the lemming.  Another interesting fact brought out in this report by Olivier Gilg of the University of Burgundy in Dijon, France, is that some shorebird species avoid breeding in areas free of lemmings, similarly decreasing their chances of having their eggs eaten by the Arctic Fox.

Check out the full story at NPR or listen to it here.  They have a very cute photo of the White-rumped Sandpiper chicks you shouldn’t miss.