• Total amount of resource harvested in a given time span 



• 



Degree of discards and by-catch, i.e., in a mixed demersal fishery 

 utilizing nets--which are relatively unselective--species of no 

 market value are usually discarded, and often other species of value 

 are caught while directing a fishery at a particular species. 



5. Interrelationships Among Species Information 



• Identification of marine food chains and trophic levels 



Analysis of impacts of fishing activities on those interrelationships 



The premise here is that awareness of the natural ecological system, 

 combined with analysis of fishing activities in that system, will serve to 

 predict an allowable harvest on a continuing basis. Thus, resource abundance 

 studies are necessary, as well as data on the level of human harvesting effort, 

 location, type of gear, and efficiency of gear* Fishing mortality , when added 

 to natural mortality , affects the size of the stock in that the degree of 

 mortality is greater than that resulting from "natural" factors (not con- 

 sidering man), and may, if unregulated, so deplete the population that it 

 cannot recover. 



Georges Bank assessments are primarily carried out by NMFS personnel lo- 

 cated at Woods Hole, Massachusetts. Until recently, such efforts were 

 lacking in funding and consequently the comprehensiveness of the assess- 

 ments was limited, concentrating on species of interest to American fisher- 

 men. In 1964, NMFS received a research vessel (Albatross IV) with which to 

 perform survey tows, determination of unit stocks, population parameters of 

 that unit, and environmental effects. Such surveys have been undertaken in 

 the fall and the spring of the year, limited somewhat by budget and opera- 

 ting problems of the vessel. Effects of human activities on stocks have 

 been gathered by ICNAF documentation, NMFS landing figures for the domestic 

 industry, and some selected engineering studies. Broadly, the assessment 

 community for Georges Bank has done an excellent job given the level of 

 funding, international problems with foreign fishing data, and lack of en- 

 forcement for management decisions; extension of jurisdiction has for the 

 first time instituted a formal national recognition of fisheries resources 

 and the funding necessary to manage those resources. 



