A student takes an Eckman dredge sample in the shallow water of Cutler Reservoir, Utah. After the dredge is lowered into the soft sediments, a messenger is dropped down the line, tripping the springs on the dredge that close the jaws and capture the sediments. The mud can then be processed for various components. In this case the student was sampling the benthic invertebrates (insects, snails, worms, etc) that live on the bottom of the marsh.


Photo: 28 September 2007