Rare Species as Bioindicators in Marine Monitoring
Soft-bottom invertebrates commonly form the core of marine moni- toring studies. Accordingly, those species which occur frequently and abundantly are favored in analyses, and rare species are normally excluded from consider- ation. Since rare species commonly occur at their geographic limits under sub- optimal conditions, it has been postulated that they would be vulnerable to natural and anthropogenic stresses. We examined the potential of rare species as bioin- dicators in monitoring a major marine outfall on the San Pedro Shelf, California. A rare species was operationally defined as occurring only once per sample (0.1m 2 Van Veen Grab). Based on 780 quantitative benthic samples, distributed over thirteen 60 m (outfall depth) stations, and 12 years, we concluded that the number of rare species generally declined towards outfall stations. We suggested that a more conventional definition of rarity based on actual geographic range might provide an increased degree of sensitivity to identify bioindicators.
Maurer, Don and Gerlinger, Tom
"Rare Species as Bioindicators in Marine Monitoring,"
Bulletin of the Southern California Academy of Sciences:
Available at: http://scholar.oxy.edu/scas/vol98/iss3/2