Fish assemblages and indicator species: reef fishes off the southeastern United States

Most approaches to f ishery management rely on results from stock assessment. Data-limited situations, however, may not conform to conventional assessment methods, necessitating other approaches to management (Kruse et al., 2005). One possible approach with data-limited stocks is to assign them to assemblages that are managed as units. Ideally, each assemblage would include at least one data-rich species that could be assessed and serve as a status indicator of the entire unit. Managing assemblages by means of indicator species is arguably a small but practical step in the direction of ecosystem-based management (Hall and Mainprize, 2004). Assemblages may be defined by similarities in such biological characteristics as life history, trophic behavior, or home range. For the purpose of fishery management, however, an assemblage should consist of species caught together, if regulations on fishing are to benefit assemblage members. This is particularly true if regulations are focused on an indicator species but the intent is also to control the harvest of other species in the assemblage. Indicator species have been used in management of both terrestrial and marine systems (Simberloff, 1998; Zacharias and Roff, 2001). The term “indicator species” has no single definition (Landres et al., 1988); it is used here as suggested by the National Standard Guidelines of U.S. federal fishery management, which states that where maximum sustainable yield (MSY) cannot be specified Fish assemblages and indicator species: reef fishes off the southeastern United States