The Endangered Species Act has become unwieldy. Time for a change THE delta smelt lives in brackish water, eats zooplankton and usually grows no longer than three inches (7.6 cm). It is not the sort of creature that environmentalists put on posters. But the little fish may prove as potent a symbol of America's odd approach to conservation as the California condor or the grey wolf. On August 31st a federal judge ruled that giant pumps supplying water to much of southern California were killing the smelt, which is protected under the Endangered Species Act. Those pumps will now have to shut down for much of the year, reducing water output by up to a third. When the Endangered Species Act was signed in 1973, it was expected to protect charismatic fauna such as the bald eagle and Yellowstone's grizzly bears. These days it covers such obscure life-forms as the Stock Island tree snail, the Banbury Springs limpet and the triple-ribbed milk-vetch, along with 1,348 other animals and plants. In the absence of other powerful laws, it has become the chief weapon of environmentalists