Gray, R. H., and J. M. Haynes. 



1977. Depth distribution of adult chinook salmon (On- 

 corhynchus tshawytscha) in relation to season and gas- 

 supersaturated water. Trans. Am. Fish. Soc. 106:617- 

 620. 



1979. Spawning migration of adult chinook salmon (On- 

 corhynchus tshawytscha) carrying external and internal 

 radio transmitters. J. Fish. Res. Board Can. 36:1060- 

 1064. 

 HardenJones, F. R. 



1968. Fish migration. Edward Arnold Publ., Lond., 

 325 p. 

 Hasler, a. d., a. T. Scholz, and R. M. HORRALL. 



1978. Olfactory imprinting and homing in salmon. Am. 

 Sci. 66:347-355. 



Haynes, J. M. 



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 and white sturgeon. Ph.D. Thesis, Univ. Minnesota, 

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Johnson, j. H. 



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James M. Haynes 



Department of Biological Sciences 

 State University College 

 Brockport, NY 14420 



ROBERT H. Gray 



Freshwater Sciences, Ecosystems Department 

 Battelle, Pacific Northwest Laboratories 

 Richland. WA 99352 



MATURITY, SPAWNING, AND FECUNDITY OF 



ATLANTIC CROAKER, MICROPOGONIAS 



UNDULATUS, OCCURRING NORTH OF 



CAPE HATTERAS, NORTH CAROLINA 



The Atlantic croaker, Micropogonias undulatus, is 

 an important inshore, bottom fish ranging from 

 the Gulf of Maine to Bay of Campeche, Mexico 

 (Chao 1978). United States commercial landings 

 have reached 50,000 metric tons (t) in recent years 

 (Gutherz et al. 1975; McHugh 1977), though 

 dramatic declines in landings have occurred; at 

 least in the area from Cape Hatteras, N.C., to Cape 

 Cod, Mass. (Joseph 1972). White and Chittenden 

 (1977) have postulated the existence of an abrupt 

 change in life histories and population dynamics 

 of Atlantic croaker and other species whose ranges 

 traverse Cape Hatteras. They showed differences 

 in spawning times, size at maturity, maximum 

 size and age, and total annual mortality rates of 

 Atlantic croakers from north and south of Cape 

 Hatteras and speculated the differences may re- 

 sult from different temperature regimes. 



Few studies exist on reproduction of Atlantic 

 croaker occurring north of Cape Hatteras. Wallace 

 (1940) studied size at maturity and sexual de- 

 velopment offish from Chesapeake Bay and ocean 

 waters off Virginia and North Carolina. Welsh 

 and Breder (1923) reported size and age at matur- 

 ity based on collections from Massachusetts to 

 Florida. Occurrence of larval stages and gonad 

 development indicated that spawning occurred 

 from July through December and peaked during 

 October and November (Welsh and Breder 1923; 

 Hildebrand and Schroeder 1928; Wallace 1940). 

 Haven (1957) and Chao and Musick (1977) found 

 indications from juvenile length frequencies of 

 late winter or early spring spawning. The only 

 report of fecundity was that a 395 mm female 

 contained approximately 180,000 eggs (Hilde- 

 brand and Schroeder 1928). 



This paper presents size at maturity, spawning 

 times as indicated by ovarian development, and 

 fecundity observations of the Atlantic croaker 

 population north of Cape Hatteras. 



Methods 



All fish were collected during seven National 

 Marine Fisheries Service bottom-trawl surveys of 

 the continental shelf from Cape Hatteras to Block 

 Island, R.I., during 1973-76 (Table 1). The survey 

 design and sampling methods were described by 

 Grosslein (1969). Atlantic croakers were captured 

 each year between lat. 39°00' N (Cape May, N.J.) 

 and 35°15' N (Cape Hatteras) in depths from 7 to 

 131m. 



Subsamples of approximately 25 fish, represen- 

 tative of the length frequency of each catch, were 

 frozen whole for laboratory examination. Each 

 fish was weighed (grams), measured (millimeters 

 total length, TL), sexed, and its maturity stage 

 was determined using the sexual development 

 classification and criteria of Wallace (1940). 



Table l. — Summary of Atlantic croaker data collected between 

 Cape May, N.J., and Cape Hatteras, N.C., during 1973-76. 



190 



FISHERY BULLETIN: VOL. 78, NO. 1, 1980. 



