Biological Criteria for Protection of U.S. Coral Reefs

Coral reef ecosystems are threatened by natural stressors, human activities, and natural stressors exacerbated by human activities. Under the U.S. Clean Water Act, States and Territories may guard against anthropogenic threats by adopting water quality standards based on biological, physical, and chemical criteria. The condition of biological communities is a more dependable water quality standard than are physical and chemical attributes because living organisms are responsive to effects of low-level, chronic, cumulative, interacting point- and nonpoint source pollution. The President’s Ocean Action Plan directed the U.S. Environmental Protection Agency (EPA) to develop biological assessment methods and tools for evaluating the health of coral reefs so that States and Territories could more easily establish biological water quality standards, including descriptions for designated waterbody uses and biological criteria (biocriteria). Biocriteria are qualitative or quantitative thresholds of biological condition necessary to sustain the designated uses. Rigorous biological assessments are needed to identify metrics that reflect biological characteristics and are responsive to a gradient of human disturbance, and to generate defensible long-term monitoring programs. Implementation of biocriteria for freshwater ecosystems has forged a process that can be adopted for coral reefs. EPA is fostering development of coral reef biocriteria through research, evaluation, and collaboration.