Chapter 1 1 

 Fishes 



Authors: Patricia Shettig, Stanley Chenoweth, Beth Surgens 



Over 100 species of fishes, representing 40 families, inhabit the marine, 

 estuarine, and freshwater systems of coastal Maine. The majority are resident 

 species, and many have commercial and recreational value. Fishes are both 

 predators and prey in aquatic food chains and play an important role in energy 

 flow within aquatic systems because of their great abundance at different 

 trophic levels. 



Fishes generally can be classified into two major categories: pelagic and 

 demersal. Pelagic fishes (e.g., herrings, mackerel, and striped bass) are 

 highly mobile and range freely throughout the water column. They feed mostly 

 on plankton and other pelagic organisms. Demersal fishes (e.g., flounders, 

 sculpins, and cod) are less mobile and usually stay on or near the bottom. 

 These fishes feed mostly on benthic invertebrates and other bottom fishes. 

 Freshwater fishes, for the most part, are semidemersal in habit. Because most 

 marine and estuarine fishes are highly mobile, geographic and habitat 

 preferences are difficult to identify. 



The habitat and food requirements of most fishes vary according to the life 

 stage of the fish. If fish resources are to be managed effectively the 

 environmental requirements of species or groups of species at each life stage 

 of the fish must be understood. Unfortunately, very few of these requirements 

 are known. 



This chapter discusses the status and distribution of fish species in coastal 

 Maine habitats and systems and the factors that influence their distribution 

 and abundance. Marine and estuarine fishes are emphasized. Natural factors 

 that affect the distribution and abundance of fishes include salinity, 

 temperature, food availability, streamflow and cover, competition, predation, 

 and disease. Water pollution, barriers tc migration, and overharvesting 

 (overfishing and selective fishing) are the most severe limiting factors to 

 fish populations in coastal Maine. 



11-1 



10-80 



