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Thursday, April 7, 2016

Islands on Dry Land

One of the biggest problems of romanticizing "The Wild" is that is overlooks the fact that it doesn't exist anymore.  That is, it doesn't exist in any appreciable amount, if you think of "The Wild" as a place were animals live free of human influences.  Centuries ago, the planet consisted on broad expanses of nature with small pockets of human civilization here and there.  Now, we have a planet of human civilization, with small patches of wildlands scattered haphazardly.

These wild patches vary in size from hundreds of square miles to tiny plots of woodland and meadow.  Standing in the middle of the Serengeti Plains of Tanzania, or Manu National Park in the Peruvian Amazon, you might think of yourself in the wild... and in a sense, you are.

The problem with many of these wild areas is that, as big and inspiring as they are, they are much too small for their stated purpose: protecting wildlife.

Confused?  I'll turn it over to Bill Conway, formerly of the Bronx Zoo, who summed it up perfectly in his book, Act III in Patagonia:

"'Deep Thought,' the pensive computer in Douglas Adams's 1978 Hitch-Hiker's Guide to the Galaxy, explained, 'The answer to the The Great Question... Of Life, the Universe, and Everything is forty-two,' an agreeably brief reply.  However, several wildlife population biologists have concluded that the answer is closer to seven thousand.  The 'Great Question' that those scientists are trying to answer is, How big of a wild, free-living, adult population of a species is needed to ensure its long-term persistence?  Consequently, how big should we make its reserves (as though we have much of a choice)?

Essentially, the problem is that most protected areas are too small to support viable populations of the animals that live there.  Animals may want to leave the protected area to colonize other wild areas, or to find mates, or whatever the reason, but they can't.  People are in the way... and their farms, and their factories, and their roads.  Roads.  That's right - plenty of animals will refuse to cross roads.  Especially arboreal animals that would have to come to the ground.  You can have a ribbon of road between two patches of jungle, and for some species it might as well be the Great Wall of China.

Some barriers are a little more obvious than others.  Not to get too political, but if a certain presidential candidate gets his way and builds a wall on the US-Mexican border, there are a lot of animal populations which are going to be cut off.  So much for efforts by ocelots, jaguars, and pronghorn, among other species, to move back and forth.

So what to do about these small pouches of wildlands?  Animals can't move between them.  In some cases, the answer is to try to play connect-the-dots with these protected areas by establishing corridors.  A corridor is a strip of habitat that joins two habitats, allowing animals to move safely between the two, effectively making them one habitat.  A great case study of that is the work that Alan Rabinowitz and Panthera have been doing in Central and South America, trying to create one continuous corridor of jaguar habitat down the spine of the continent.

The problem is that some species are very sensitive and won't use these corridors.  So, sometimes, that necessitates people to do the moving for them.  With some endangered species, particularly large ones that occur at lower population densities, it may be necessary to capture animals from one mini-population and transfer them to another... just like how zoos move animals around to promote genetic diversity.  In fact, it's in this area that zoos are best able to contribute in some cases by applying their expertise of animal capture, restraint, and transport to make these animal moves feasible.

To some people, it seems perverse to watch wild animals get darted, blindfolded, trussed up, put on the back of a truck, blood and DNA sampled, ear-tagged, and then turned loose in a totally new area.  It speaks against their core belief that nature should be natural, and wildlife should be left wild.  Ideally, that's how things would be.  The fact is, however, that for some wild species, we've just let things get too far gone for that.  Some species will not survive unless they are managed.  Their populations are too small, too scattered, and too isolated to remain viable.

It's a nice thought that wild animals should be left wild.  But here's another thought - we got these species into this mess.  We should be willing to get them out of it.

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