Marine monitoring programs are usually long-term, data intensive programs that establishes points of reference for environmental conditions and then attempts to document and identify change in these conditions over time. Programs using macrobenthos and water quality measures are widely used in marine and estuarine settings. Assessment programs, smaller in scope and application, are generally more short-term and data-specific than typical monitoring programs. They are intended to measure specific parameters or conditions. Bioassay is a type of assessment program that uses live organisms to measure a variety of conditions or specific impacts.