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.