The river is used for recreation and agricultural, municipal and industrial water supply. It also provides wildlife habitat, including cold freshwater habitat for fish migration and spawning. The Mattole River is home to three salmonid species listed as threatened under the Federal Endangered Species Act: chinook and coho salmon, and steelhead. Coho salmon are additionally listed as threatened under the California State Endangered Species Act. The Mattole Salmon Group counted just three adult Coho salmon in the river in the 2009-2010 winter (and only one redd), which is the lowest number of coho counted since the group began surveys in 2004. This is far below the 19th-century historical estimates of 17,000 to 20,000 adults annually, or the 1950s and 1960s estimates of 8,000 and 5,000 annually, respectively. In 2010–2011 ten coho were counted and five redds, but these numbers are 95% lower than 2006–2007. Each salmon run is on a three-year cycle.