Icy layer making access to food difficult for muskoxen (Ovibos moschatus), Dovrefjell, Norway. Thaws and subsequent freezing can lock up the vegetation, making it inaccessible for ungulates such as reindeer and muskoxen. This thaw happened in early February. If the food gets locked up earlier in the winter the animals are less likely to be able to survive because spring with new green vegetation is further away. This is one of the things that is associated with climate change.

When we were there the muskoxen were on the move... several times we would move camp to be closer to where we had seen the animals only to find them gone the next morning. It may be that they were trying to find places where they could still access food. When we finally found animals that stayed put it turned out to be both bulls and cows and calves. My friend Niels had not ever seen that during the previous six winter trips; not these rapid and frequent movements, not the mixed gender groups. The bulls typically live separate from the cows and calves except during mating season. I was sitting on a rock thinking about this... to the casual observer it may all look "normal" ... there is snow, and it is cold. It is only when you dig deeper that you find the food is inaccessible because of the icy layer, the animals may be moving around more to find places where the vegetation is not locked in the ice, and the animals now forage in mixed groups because there are only so many places that don't have the icy layer...  Cold weather and more snow later in February don't even out that early thaw... if the icy layer persists, then that is what matters for the animal's survival. 

Icy layer making access to food difficult for muskoxen (OvibosIcy layer making access to food difficult for muskoxen (Ovibos moschatus), Dovrefjell, Norway Ice layer as a result of a melt in early February made food hardIce layer as a result of a melt in early February made food hard to access for the muskoxen, Dovrefjell, Norway

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