From the archives - today 6 years ago

2007-07-16 Northern collared lemming. This lemming were living under our house.

Lemming Carcass

 Carcass of northern collared lemming, found next to a lemming winter nest

As part of our field work in BioBasis Zackenberg we monitor the northern collared lemming. This is done by counting the winter nests in a certain area every year. The nests are under the snow but we count them after they snow is gone. This year the number of nests were rather large after years of extremely low. In a few of the nests there was indication that an ermine (also known as stoat) had killed one or more lemmings and taken over the nest. They use the fur of the lemming to line the nest. Rarely, we find a full skeleton as above. 

Blue foxes and lots of lemmings

We see them everyday - not the blue foxes but the lemmings! They are northern collared lemmings and they seem to have had a good winter! Under the thick layer of snow they have bred and multiplied and are now being caught by predators like the long-tailed skua and the arctic fox. The arctic foxes are really doing well and all 5 of the 5 breeding dens are active and with many pups (at least two with 7 or more). When I was seeing some of the pups the first time at our highest placed den, I thought that some of them might be of the dark colour form also know as "blue fox". White arctic fox pups are very dark and uniformly coloured brown when they are very small and first emerge from the den holes in late spring but they soon turn lighter on the underside, inside the ears and around the eyes - much like the adult white fox's summer coat. Although I only got a glimpse the first time, a few of the pups were definitely NOT lighter anywhere. Last time I went to the den my suspicion was confirmed. It was now very clear that there were two different colour forms. I got some rather nice photos where the difference was easy to see and then a dark adult showed up with the mouth full of lemmings! It took a little detour to the den as it discovered me close by. I took a few photos of it too before I left. Sadly, this den is rather far away and high up on a slope so I cannot visit it often, but other dens are closer by and I look much forward to follow the pups for the next short while and again after I return from a break.

Clever skua

The other day I did an interesting observation of a long-tailed skua. I was on my way back to the station after checking some fox dens as I saw the bird with something big in its bill. I soon realised that it had caught a collared Lemming, so I approached slowly after getting the camera ready with the long lens. It let me come very close without seeming to get nervous. The lemming was still pretty much intact but while I was photographing, it managed to get it open by holding it with its sharp bill and kind of throwing it towards the ground, using the weight of the lemming. It then started to eat the intestines of the rodent. When a glaucous gull flew past, the skua immediately dropped the lemming on the ground and started to walk around pecking "at insects" and minding its own business... but as soon as the gull had passed the skua quickly went back, grabbed the lemming and flew off with it to the other side of the river. On the other side of the river there are a lot of musk oxen gathering. Some of them looked like they would like to cross yesterday but did not dare. On this side a bull and a young female are lying right next to one of our plots. Tomorrow, I try to persuade them to let me do the check of plants and measuring of greenness. Otherwise musk oxen numbers are steadily increasing in our census area with 44 individuals recorded from the roof top yesterday.