MANAGEMENT OF GROUNDFISH STOCKS 



Fisheries for coastal gfroundfish present a complex man- 

 agement i)roblem; U.S. and foreign fishermen seek and catch 

 the same stocks in international waters. The function of 

 groundfish research is to su])p!y information and analyses 

 to guide decisions by management. 



During the coastal hake fishing seasons of 1965-67, bi- 

 ologists sampled fishermen's catches as they were brought 

 to the processing plant at Aberdeen, Wash. Additional fish 

 were collected by a charter vessel in 1968. Biological data 

 from several thousand fish collected from British Columbia 

 to California through all seasons were processed by auto- 

 matic data-processing equipment. 



The data on ages of hake indicated that the population 

 contained almost no fish born in 1962 and 1963. Because 

 of the apparent absence of recruitment, a rather high rate 

 of natural mortality, and heavy Russian fishing in 1966-67, 

 biologists forecast a low abundance of hake off Washington 

 and Oregon in 1968 unless a strong 1964 year class appeared. 

 There was no U.S. coastal fishery for Pacific hake in 1968. 

 but a proposed exchange of information with the Soviet Union 

 will be useful in confirming this hypothesis. 



Contacts between the Russian and United States gov- 

 ernments led to meetings of scientists at our laboratory in 

 July 1967 and in Moscow in October 1968. The discussions 

 led to agreement on the current status of stocks of hake 

 off Washington and Oregon and of ocean perch in the Gulf 

 of Alaska. Plans were made for coordinated cruises and 

 surveys, exchange of biological and catch data, and eval- 

 uation of models of populations. 



Age Analysis and Genetics 



As with salmon, improved techniques to distinguish ages 

 and stocks are fundamental to studies of groundfish. 



FIGURE 46.— Otolith (car bone) from hake magnified about 

 4 times, age 8 years. Otoliths arc better than scales for 

 showing age of Pacific hake. 



To standardize criteria for reading their ages from scales 

 or otoliths (ear bones), a cooperative age-reading unit was 

 established at the laboratory (fig. 46). Two Bureau biol- 

 ogists work part-time; the Washington State Department 

 of Fisheries and the Pacific Marine Fisheries Commission 

 each provide a full-time technician. The unit has completed 

 age readings for more than 4,000 Pacific hake and Pacific 

 ocean perch. 



Biochemists have made considerable progress in the search 

 for genetic markers that may be useful in racial studies. 

 A protein in eye fluids, an iron-binding protein in blood, 

 and LDH enzymes of the liver (fig. 47), tested in hake from 

 Puget Sound and the Pacific Ocean, provided genetic evidence 

 that the Puget Sound population is separate and isolated 

 from ocean populations. Preliminary work has been done 



35 



