by Guest Blogger
July 18, 2005
I refer, of course, to that distinctive arctic plant eater, the musk ox
(Ovibos mochatus) with its famously warm longhaired coat.
There are 103
of these shaggy beasts in this valley, or at least there were yesterday
when Toke Thomas Hoye counted them. He’s a PhD candidate with the
University of Copenhagen, working at the station this summer, and musk
ox counting is part of the job.
“I start on that small hill,” he
explains pointing at a hill some ways off. “From there I can see where
the herds are and plan my walk.” The walk covers a roughly 19-mile
(30km) circuit through the valley, and at times there are almost 200
musk oxen in the valley – a healthy population level.
Today, Toke grabs his gear and we walk a short way
past the airstrip to where a couple of older males are grazing. Toke uses binoculars and a
tripod mounted spotting scope to count the musk oxen and classify them
by age and sex. He can tell these are older males from the shape and
size of their horns. When they’re calves both genders look the same,
but by the time they’re a year old, males have small pointy horns coming
straight out the sides of their heads and a lot of white wool in the
middle of their forehead.
Global warming and musk ox
For Toke, the challenge of looking at the ecosystem as a whole is much
more interesting than focusing on one species.
He stresses that because
so many of the variables are interlinked the overall effect of global warming is difficult to predict.
What’s more, there are still a lot
of questions about musk ox behavior, and other variables, in the
winter. The science station operates only in the summer, and research
here in the winter would be a major logistical challenge, requiring
funding they simply don’t have.
What happens in the winter is an especially important part of the puzzle
when it comes to musk ox because, as Toke described it, winter is the
“survival bottleneck” for the animals. It’s known that musk ox numbers
in northeast Greenland can vary greatly from year to year. These changes
in population seem to coincide with changes in winter temperatures, and
oddly enough, warmer isn’t necessarily better.
As Toke explained, “We have graphs in our mess room where the
temperature declined nicely over winter, and then suddenly there was
this blip of positive temperatures over a day or so and then it dropped
back again.” In fact, temperatures of 11 degrees Centigrade (52 F)
were recorded for several hours in February this year. In general, this
sort of thing is not a new phenomenon, but this year was the first time
temperatures above freezing have ever been recorded in February.
You’d think in a place where the temperature gets down to -40 degrees
Centigrade (-40 F), a few days of warmer weather would be a welcome
development for the musk oxen. But the snow melted by the brief thaw
soon refroze into a thick layer of ice – covering the ground vegetation
that the musk ox depend on for food.
Winter is already the hardest time
of the year for these animals, and many calves don’t live through their
first. If these ice crust episodes become more frequent it could spell
disaster for the musk oxen here.
Going, going, gone
Almost half a mile away, two musk oxen see us and bolt – heading off
at a good pace. We follow parallel to their course, but more slowly.
At the top of the next rise, they stop and face each other. “Have a
look now, they might have a fight,” says Toke. Sure enough, they run at
each other and clack heads. After a brief shoving match, they walk on.
This behavior was puzzling because there are no females around to
impress. Toke thought it might have been a sort of stress relief
response to being spooked. Soon we give up following. “Once they
start to move, they move for a while,” he explains.
Watching the musk ox jog off into the distance, I realize that what we
have here is an allegory. Once you provoke a response, you sometimes
can’t control what happens next. And, small actions can have big
consequences. All we did was cross an imaginary line, almost half a
mile from the musk oxen. The difference between them ignoring us, and
them running, was only a matter of a few steps across that line, but
there was no way to know exactly where that line was until we crossed it.
The same could be said for global warming. If we keep adding greenhouse
gasses to the atmosphere, at some point we might cross a line where
feedback effects take over – continuing to heat up our planet no matter
what we do from there on.
Of course, this is just an allegory. Reality is more complex. In
reality, global warming is already happening – it’s only a question of
how far it will go, how much damage it will do and how much we can slow
it down. In reality, there are also ways to move forward (renewable
energy and energy efficiency) without changing the climate.
But the reality is also that business continues as usual, unless we make
a real effort to change it.