Canary:Coal Mine::Delta Smelt:?

You’ve got your charismatic megafauna, like polar bears, losing their Arctic pack ice habitat as the poles warm. Everyone loves polar bears. (Including me.)

Then there are the tiny little creatures, the ones whose listing as endangered raises nothing but ire that such an insignificant mite could hold up human activity. Such as, say, the Delta smelt. But these tiny creatures are so much more vulnerable to habitat degradation, to pollution, to man-made changes in the environment. Their travails are ours; they’re telling us that something is seriously wrong.

So biologists at the UC Davis Fish Conservation and Culture Laboratory are breeding Delta Smelt in captivity, to keep the species alive, since they are almost sure to go extinct in the wild in the next few years.

The lab is creating the refuge population from a parent generation of just 500 smelt gathered from the Delta in December 2006. These are the last wild fish the lab was able to obtain before officials halted scientific collections in the Delta – another drastic step taken to protect the species.
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There are currently no plans to reintroduce these fish. In fact, almost no one wants that to happen yet. At the moment, they represent only a backup plan.

Is this the ecosystem that we’re “managing for?”