Winter feeding red foxes harmful to breeding birds at Slettnes

It is late June and skua nests should be hatching right now, and one should stumble over chicks on the tundra. Instead pairs are hanging around with nothing else to do than sit at their territory and fly to sea to feed from time to time. Of a total of 40 nests, 33 were predated by red foxes, two more by gulls. In the four years we have worked here so far, we never encountered such high predation rates. One could argue that foxes follow our tracks and we as researchers lead them from nest to nest. Even though we are very careful at nests, our scents will definitely play a role. However also nests that we did not approach, but only observed from a distance disappeared. And all nests disappeared very shortly after they were started. Not only the skuas, but also waders in the area suffer from fox predation. Barbara Ganter and Hans-Ulrich Rösner, who have investigated the Dunlin population here over 25 years, also see more predation than usual.

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pair of Arctic skua after they lost their nest

We visited the active fox den in the area and it made an impression of a lavishly set table: parts of a reindeer calf, remains of several gulls, feathers spread out all over the place. Four nearly full grown young foxes are regularly playing outside the den. A fox den has several entrances and a few were stuffed with even more food: a reindeer calf and a complete cormorant. We guessed the 66 skua eggs were also hidden somewhere inside the den!

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remains of a reindeer calf inside a red fox den

And foxes are not the only threat: because of late snow melt the reindeer herd could not feed in the mountains and arrived here extremely early and in much larger numbers than usual. Now 600 reindeer cross the area on a day to day basis. Not only can they trample nests, they will eat eggs if they come across them. Resting herds are often found lying in the middle of known skua territories for hours, preventing them from going back to their nests.

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how friendly they may look: in the current numbers they pose a threat to the birds at Slettnes

 

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