Table 7. Biological Attributes 



Terms used in Table 7. Biological Attributes: 



Life Mode - The usual location within the water column. 



• Benthic - In the bottom sediments. 



• Epibenthic - On, but not in, the bottom. 



• Demersal - In the water column, but near the bottom. 



• Nektonic - In the water column away from the bottom, and capable of locomotion. 



• Planktonic - In the water column, but not capable of extensive movements. 



Spatial strategy - Use of habitats by life stages. 



• Freshwater resident - Resides primarily in freshwater habitats. 



• Estuarine resident - Resides primarily in estuarine habitats (salinities >0.5 and <25%°). 



• Marine resident - Resides primarily in seawater habitats (salinities >25%o). 



• Coastal migrant - Migrates within nearshore waters of the continental shelf. 



• Ocean migrant - Migrates in ocean waters beyond the continental shelf. 



Mobility - 



• Non-mobile - Sessile or sedentary. 



• Low mobility- Capable of limited directed movements. 



• High mobility- Capable of extensive directed movements. 



Feeding Type - 



• Filter feeder - Obtains food items by filtering water or fine sediments. 



• Non-filter feeder- Obtains food items by other means, such as selective predation. 



Prey Items - Food items typically consumed by an organism, such as detritus, phytoplankton, zooplankton, fish, 

 etc. 



Longevity - Average lifespan of a particular life stage, from 1 day to >20 years. 



Value- 



• Recreational - Often sought and harvested by sport anglers. 



• Commercial - Harvested by commercial fishermen for market. 



• Ecological - Of major importance in aquatic ecosystems as a predator or prey species, etc. 



• Indicator of stress - Often used in studies of environmental stress. 



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