Bears & Otters

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After a previous post on M13, one of only two free-roaming bears in Switzerland, I started wondering about bear populations in the rest of western Europe.

As it turns out, France has a grand total of 22 bears currently living in the wild, their range being the length of the Franco-Spanish border along the Pyrénées mountains. All 22 have adorable names like Cannelle (Cinnamon). The French government has a sizeable budget to reimburse farmers whose livestock or beehives have been damaged by the bears. Overall, of the thousands of sheep that roam the mountains, approximately 15,000 are lost each year for a variety of reasons – of those 15,000, only 200-300 are estimated to be lost to bear attacks (according to French government reports). Last year, a grand total of 3 beehives were judged lost to bears. This is across a range of over 7500 sq. kilometers (3000 sq. miles). Yet local farmers and tourist offices often claim the bears are a severe threat to their livelihoods.

I read how other countries that have much larger bear populations, mostly in eastern Europe, respond to this kind of outcry. First of all, where there are a lot of bears, there is also a higher tolerance for shooting bears, which is not the case in France and Switzerland. Second, and more importantly, those living in bear country know how to deal with bears. They put up better fences, they don’t expect to lead a life free of the occasional bear visit, they calculate the occasional loss of a grazing animal as the cost of being a livestock farmer in bear country. They remember how humans live alongside large predators.

This got me to thinking: In ecosystems of any kind, what is the overall benefit of large predators such as brown bears? And I don’t mean in terms of a healthy, natural balance, or a feel-good notion of things being as they ought to be, or even the right of species to survive our human sprawl. I mean: Why are conservationists trying so hard to reintroduce large predators in the form of miniscule populations that cannot possibly survive without decades of outside assistance in terms of breeding and protection?

The programs may seem intuitively correct to me, and I may have a deep inclination to support them for a variety of reasons, but what do they really bring in terms of environmental and economic benefits that I could express to someone less positively inclined?

Then I found this. It’s a paper recently published by Chris Wilmers and colleagues in Frontiers in Ecology and Environment that discusses the extent to which top predators increase the amount of carbon stored in ecosystems. The study focuses on the amount of sea kelp present in area both with and without those darling marine predators, sea otters. The paper included this appealing illustration:

The authors conclude that while marine and terrestrial ecosystems differ in too many ways for a direct comparison, the presence of top predators is indeed a strong force in the sequestration levels of carbon in a given ecosystem. This can have larger economic implications, depending on the level of plant life in each ecosystem and relevancy to crops and livestock (i.e. the issues that interest humans), not to mention the function of various fauna and flora further down the predator’s food chain.

If I understand this line of argument correctly, for example, if the vast range of the Pyrénées is to be kept intact on any level as a functioning ecosystem, with humans and livestock and tourists, it probably needs its bears. The alternative is that over a term longer than we have currently catalogued (bears have been scarce there for about a century), it will change irrevocably into a different ecosystem.

Sea otters in kelp

 

 

3 responses »

  1. Pingback: Rippling the Surface | champagnewhisky

  2. Pingback: Wolf Trap | champagnewhisky

  3. Pingback: The Biology Thing | champagnewhisky

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