It's easy to overlook minute animals like the Hay's spring amphipod. Full-grown individuals only reach about one centimeter in length, and they're not fond of the limelight. They live almost all their life underground, deep in small crevasses and cracks of small freshwater springs, where they subsist on a modest diet of decaying leaves and other organic materials from the forests around them. Because they spend their lives in darkness, they are blind and lacking pigment; accustomed to being left alone, they're extremely sensitive to disturbance.

When the Hay's spring amphipod was protected under the Endangered Species Act in 1982, biologists thought that this species' habitat had been reduced to just a single, tiny spring inside the Smithsonian National Zoo — less than two square yards of habitat on Earth. Its habitat is so fragile that to this day the exact location of this spring is kept strictly confidential, since a simple act of carelessness or of vandalism could easily destroy it.

Over the years a few very dedicated biologists have conducted additional surveys in Rock Creek Park in Washington, D.C. and Maryland and have discovered eight or so additional locations where the amphipods live. That's good news for the tiny animal, but these few freshwater springs are just a tiny remnant of the unique freshwater environment of Rock Creek Park, whose springs, in the 19th century, used to provide much of the drinking water to residents of the city. But intensive development both inside and outside the park has destroyed and degraded most of the springs, and every water body in Washington is now considered to be impaired for aquatic life under the Clean Water Act.

The Center is working to protect the Hay's spring amphipod by focusing on the main threats to the species: habitat fragmentation in Rock Creek Park, badly planned urban development and water pollution. We filed a notice of intent to sue to protect the species from development in June 2014.

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2014 notice of intent to sue



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The Endangered Species Act

Contact: Brett Hartl

Photo of habitat for Hay's' spring amphipod by Brett Hartl