Monday, September 10, 2007

Polar Bears and Fish

The press was full this weekend of a story about some biologists proclaiming that sixty percent of the polar bears will disappear as a result of the eminent loss of year round Arctic sea ice cover. They even stick in dates, carefully chosen to coincide with their unlikely presence on earth.

The idea that the ice could be just as gone in the next five years, simply does not occur to them. My own instincts tell me we only need a couple of more summers like this one to finish the job. The only remaining question is how much sea ice will normally remain at the end of season in the form of diminishing drift floes. After all it takes time to demolish a winter's sea ice covering the whole Arctic.

What I do know is that my reckless in your face prediction as this issue emerged several years ago was hesitant. And I am still been hesitant when I say that it is possible to remove all the sea ice in the next five years. It is unlikely but it is possible and I would be jolted if it happens.

However, the polar bears will be affected to the extent that they will see changes in their hunting grounds and a possible expansion of their primary prey population who will now be able to penetrate deeper into the arctic and in greater numbers. Remember, the polar bear is active during the Arctic winter when the sea ice is growing and inactive during the summer. It effectively hibernates. This strategy has allowed it to operate in southern Hudson Bay were they now have a five month lean period. This will never be true further north.

And yes, I know that these southern bears are under stress and are responding by having a slower reproduction rate. Rather logical don't you think. This may also occur further north but not nearly as much.

Right now we are looking at the maximal warming effect in a place like Hudson Bay unless we have a radical revision of continental weather patterns which is not really in the cards.

At the very best, they may be forced out of the Bay which is highly unlikely. So far they haven't budged. There is just too much food in the way of seals out there for them to eat all winter while us humans are holed up in our heated dwellings.

This also throws up another question which is much more interesting. Increased sunlight absorption (perhaps a hundred fold) in the Arctic seas is a fact as a result of the annual clearing of the winter sea ice. This means a major stimulus to the bottom of the food chain. And that means rather naturally a huge increase in fish stocks and those dependent on them.

In practice, over the last several years, a vast reach of the Arctic (a full half) has opened for summer fishing. It has been open waters for weeks now. The principal stakeholders are Alaska (1/3) and Eastern Siberia (2/3). This is a heaven sent opportunity for the two stakeholders to develop a sane management strategy of the fishery resource itself. They need to act like owners and work together to maximize the sustainable resource. This has never been done before in high seas fisheries and a successful model can then be implemented world wide. It is desperately needed.

A managed sea will also see the full re establishment of the whale population originally decimated in the late nineteenth century.

As far as I can see, the only danger the Polar Bear faces is sharp population expansion as their prey population expands. Perhaps I should predict a sixty percent increase in bear populations by 2050. I would have to be 102 to see that one and I am pretty sure that I would not care if I were there to celebrate the anniversary.

And by the way, take a look at the sea ice map and the related variation map. This is about as good as it gets. It will soon start to freeze up.

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