, variable, practical and relevant to management goals for long- and short-term monitoring programmes.five key criteria were used to rank the suitability of bioindicators for assessing changes in water quality on coral reefs
Suites of bioindicators and predictive models have been developed and applied successfully for assessments of ecosystem health in estuarine and freshwater systems. For example, models such as AUSRIVAS (Simpson and Norris 2000) assess ecosystem health based on assemblages of freshwater macroinvertebrates, and the SIGNAL biotic index uses the presence or absence of families of macroinvertebrates to infer levels of exposure of river systems to chemical pollutants (Chessman et al. 1997).
Specificity
Biological response is specific to the stressor of interest and not to other environmental stressors
Monotonicity
The magnitude of the biological response should reflect the intensity and duration of the stressor of interest
Variability
Biological responses should be consistent at a range of spatial and temporal scales. Ideally, there should be low background variability although a change in variance can itself be used as an indicator of an impact
Practicality
Measurements of biological responses should be cost effective, easy to measure, non-destructive and observer independent
Relevance
Biological response should be ecologically relevant and important in public perception to assist communication