Multimetric indicators developed for a particular geographic area and scale of nrionitoring effort should not be 

 applied to other scales of monitoring or other geographic areas without evaluation and modification. Because 

 of differences in the biological assemblage structure and composition, and different expectations of conditions 

 associated with minimal human disturbance, component metrics may require substitution and validation (Miller 

 et al. 1988, Barbour et al. 1995). Thus, previously existing multimetric indicators may not be useful for the 

 MAHA geographic region and monitoring framework. Likewise, this assemblage indicator should not be used 

 in any other monitoring context and/or geographic area. 



Table 4-2. Characteristics of indicator 



Basic data from fish assemblages required: 

 Presence/absence of species 

 Abundance of individual species 



Requires representative data on fish species composition and abundance be 

 collected at each sampling site. 



Metrics: Categories of species or individuals representing various aspects of ecology and 

 life history in the assemblage 



Species richness and composition 



Abundance and individual condition 



Trophic function 



Reproductive function 



Each fish species assigned to categories within each metric based on life history characteristics. 



Score for a particular metric based on comparison of observed responses to expectations under 

 conditions of minimal human disturbance. 



Each metric is assigned a score of between and 10 based on the similarity of the 



observed response to expectations. 



Indicator score is computed as the sum of individual metric scores. 

 Metrics are equally weighted 

 Indicator score is re-scaled to be between and 100 

 = no fish collected at site 

 100 = site meets all expectations for conditions under minimal human disturbance 



Assessment question(s) addressed by extrapolating indicator values from probability sample of 

 sites to entire target resource population (stream length). 



Public Perception 



Indicator score easily understood 

 • Once developed and validated, indicator does not require sophisticated technical 

 expertise to interpret 



4-3 



