Why has the U.S. Fish and Wildlife Service listed the Illinois cave amphipod as an endangered species?
Although the amphipod at one time inhabited six cave systems, more recent surveys have turned up amphipods in only three. Biologists fear that declining water quality is affecting the remaining amphipods, prompting the Service to list the species as endangered under the Endangered Species Act. Amphipods are tiny creatures. How does the Service know they are in trouble? Because of the amphipod’s small size and remote environment, it is difficult to obtain accurate counts of the species. However, scientists can determine the number of amphipod populations existing and their range. While amphipods were once known from six cave sites, they are now found at only three, indicating a notable decline in numbers of amphipods. How did the Service make its decision on whether to list the amphipod as endangered? Under the Endangered Species Act, the Service must decide whether or not to list the amphipod based on the best scientific information available. The Service examines the species’ status i
