Literature Cited 



COLLETTE, B. B. 



1978. II. Adaptations and systematics of the mackerels and 

 tunas. In G. D. Sharp and A. E. Dizon (editors), The 

 physiological ecology of tunas, p. 7-39. Acad. Press, N.Y. 



HARADA, T. 



1978. Recent tuna culture research in Japan. 5th Inter- 

 national Ocean Development Conference, Keidanren 

 Kaikan, Tokyo, September 25-29, 1978. Preprints (I), Ses- 

 sion C-1, p. C1-55-C1-64. 



LEONG, R. 



1977. Maturation and induced spawning of captive Pacific 

 mackerel. Scomber japonicus. Fish. Bull., U.S. 75:205- 

 211. 



shehadeh, z. h., c.-m. kuo, and K. K. MILISEN. 



1973. Validation of an in vivo method for monitoring 

 ovarian development in the grey mullet (Mugil cephalus 

 L.). J. Fish Biol. 5:489-496. 

 SOGO. 



1979. Bluefin tuna spawn in captivity — World's first rec- 

 ord of artificial fertilization and hatching of bluefin 

 tuna. [In Jpn.] Sogo, June 27, 1979. (Engl, transl. by 

 T Otsu, 1979, 2 p., Transl. No. 37; available Southwest 

 Fish. Cent., Natl. Mar Fish. Serv., NOAA, Honolulu, HI 

 96812.) 



Stevens, r. e. 



1966. Hormone-induced spawning of striped bass for res- 

 ervoir stocking. Prog. Fish-Cult. 28:19-28. 



Thomas, a. e. 



1975. Marking channel catfish with silver nitrate. Prog. 

 Fish-Cult. 37:250-252. 

 UEYANAGI, S. 



1978. Recent tuna culture research in Japan. 5th Inter- 

 national Ocean Development Conference, Keidanren 

 Kaikan, Tokyo, September 25-29, 1978. Preprints (I), Ses- 

 sion C-1, p. C1-23-C1-30. 



YASUTAKE, H., G. NISHI, AND K. MORI. 



1973. Artificial fertilization and rearing of bigeye tuna 

 iThunnus obesus) on board, with morphological observa- 

 tions on embryonic through to early post-larval stage. 

 [In Jpn., Engl, abstr] Bull. Far Seas Fish. Res. Lab. 

 (Shimizu) 8:71-78. 



CALVIN M. KAYA 



Southwest Fisheries Center Honolulu Laboratory 



National Marine Fisheries Service, NOAA 



Honolulu, Hawaii 



Present address: Department of Biology 



Montana State University 



Bozeman,MT 59717 



ANDREW E. DiZON 



Sharon D. Hendrix 



Southwest Fisheries Center Honolulu Laboratory 

 National Marine Fisheries Service, NOAA 

 Honolulu, HI 96812 



TROPHIC IMPORTANCE OF SOME MARINE 



GADIDS IN NORTHERN ALASKA AND THEIR 



BODY-OTOLITH SIZE RELATIONSHIPS 



Natural marine ecosystems are being subjected to 

 ever increasing human-induced stresses, includ- 

 ing expanding commercial fisheries and activities 

 associated with the exploration and development 

 of offshore petroleum resources. Numerous 

 studies of the food habits and trophic interactions 

 of marine vertebrate consumers have been un- 

 dertaken in Alaska during the last 5 yr in re- 

 sponse to increased demand for multispecies ap- 

 proaches in fishery management plans and the 

 legal requirement for environmental assessments 

 prior to petroleum development. Through these 

 and other studies the importance of three 

 species — walleye pollock, Theragra chalco- 

 gramma, saffron cod, Eleginus gracilis , and Arctic 

 cod, Boreogadus saida — in Arctic and subarctic 

 ecosystems has become increasingly appgirent 

 (Klumov 1937; Andriyashev 1954; Lowry and 

 Frost in press; Pereyra et al.^). These species are 

 widespread and locally abundant, are major sec- 

 ondary consumers, and are important prey of 

 other species (Table 1). 



Walleye pollock are found throughout the North 

 Pacific and in greatest abundance along the conti- 

 nental shelf break of the Bering Sea. Abundance 

 decreases rapidly north of St. Matthew Island, and 

 they are caught only rarely north of Bering Strait 

 (Pereyra et al. footnote 1). The species supports a 

 commercial fishery of almost 1 million t annually, 

 one of the largest in the world. Walleye pollock 

 form a major portion of the diet of all pinnipeds in 

 the southern Bering Sea, except bearded seals and 

 walruses, and are eaten by at least 4 species of 

 cetaceans, 13 species of seabirds, and 10 species of 

 fishes in that area. 



Saffron cod occur in the eastern Bering and 

 Chukchi Seas and throughout the western Arctic 

 Ocean (Andriyashev 1954). They are also present, 

 but less abundant, in the Beaufort Sea. Saffron cod 

 are utilized for food by coastal Eskimos. They 

 make up a major portion of the diet of ringed and 

 spotted seals and white whales in the northern 

 Bering and southerr Chukchi Seas. They are also 



'Pereyra,WT, J. E.Reeves, and R.G.Bakkala. 1976. De- 

 mersal fish and shellfish resources of the eastern Bering Sea in 

 the baseline year 1975. Processed rep., 619 p. Northwest and 

 Alaska Fisheries Center, National Marine Fisheries Service, 

 NOAA, 2725 Montlake Boulevard E.. Seattle, WA 98112. 



fishery BULLETIN: VOL. 79. NO. 1, 1981. 



187 



