Thursday, July 29, 2010

The Mountain Pine Beetle

While visiting the Canadian Rockies recently, I noticed large bald spots on mountaintops many of which were several acres in size. Since I have visited the area in the past, I assumed it was simply clear cutting (non-environmental friendly logging) and I didn't give it much thought. Later in the week, while I was on the white water raft ride, I noticed that these areas were not clear cut because the trees were not gone but were just very thin, many of them dead or dying. This is the work of the mountain pine beetle.

The mountain pine beetle is not only a problem in Alberta and British Columbia but in the American Rockies as well. Colorado, Wyoming, Montana and Idaho all have similar problems. The beetle is not an invasive species, it is native to North America. It's population has gone out of control because, historically, it tends to breed heavily in warm years and not so heavily in cool years. Since this past decade has been the warmest on record, the population is completely out of control and it's predators can't keep up with them. Their population is usually controlled by cold weather. Since trees are our planet's greatest source of cooling this is very disturbing news. It seems like cycle that has no chance of stopping.

Nothing in nature happens in a vacuum. Other species are always affected by another's growth. Clark’s nutcracker is a bird that lives off of the white bark pine, the type of tree that is being most devastated by the beetle. The nutcracker's relationship with this tree is a symbiotic one. The bird feeds on the cones thus spreads the seeds. When the trees die, so do they. The whitebark pine relies on the nutcracker even more for if not for this bird, the seeds would not be spread throughout the landscape. If the bird dies off so will the tree.

The squirrels and chipmunks in the area also feed off of the cones. They store them in ground caches. These caches are the main source of food for black bears and grizzlies. Since the recent Mountain Pine Beetle outbreak, grizzly attacks on humans are up because bears are going elsewhere seeking out food. When a bear attacks a human, they are destroyed. Just another casualty of global warming.

1 comment:

Beth said...

Very nice post.