There are both recreational and commercial components to the Atlantic 

 mackerel fishery; the domestic recreational catch historically exceeds the 

 commercial catch. Until 1978, the combined domestic recreational and 

 commercial catch was dwarfed by that of foreign commercial fishermen. For 

 example, during 1976, the US commercial fishermen landed 2,700 metric tons 

 (MT); US recreational fishermen landed 4,200 MT; Canadian commercial fishermen 

 landed 15,700 MT; and commercial fishermen from other countries landed 223,300 

 MT for a total of 245,900 MT (Anderson 1984). Of the commercial total 

 approximately 57% was taken in waters west of 70° longitude (Middle Atlantic 

 Bight and western Gulf of Maine). However, since 1977, regulation of foreign 

 fishing has reduced the proportion of foreign catch to approximately 10% of 

 the annual total allowable catch (Anderson 1984). 



Essentially all mackerel are mature by their fifth year, although at 

 least half of them have reached maturity by their third year. The eggs are 

 planktonic, staying above the seasonal thermocline in the upper 15 m. The 

 incubation period is temperature-dependent, and takes about 4 days at 16°C. 

 Juveniles are thought to move inshore, while the larger fish stay further 

 offshore in deeper waters (Bigelow and Schroeder 1953). 



Atlantic mackerel are opportunistic feeders. They feed both on 

 zooplankton and are active predators on larger organisms as well. 



NMFS stock assessments indicated that the total stock biomass (ages 1 and 

 older) declined from an estimated 2.515.U00 MT in 1969 to 485,000 MT in 1977, 

 then began rebuilding to about 631,000 MT at the beginning of 1979 (Anderson 

 1980). 



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