DISTRIBUTION AND RELATIVE ABUNDANCE OF 



LARVAE OF KING CRAB, PARALITHODES CAMTSCHATICA, IN 



THE SOUTHEASTERN BERING SEA, 1969-70 



Evan B. Haynes^ 



ABSTRACT 



During the spring and summer of 1969 and 1970, larvae of the king crab, Paralithodes 

 camtschatica, were abundant in plankton samples from the southeastern Bering Sea. Abundance 

 was highest near shore and generally lowest in the central and western parts of the study area. 

 As the season progressed, the center of abundance moved northeastward along the Alaska Peninsula 

 toward the head of Bristol Bay. This change in distribution was apparently related to water current 

 patterns. 



This report is based on collections of larvae of king 

 crab, Paralithodes camtschatica, made by the 

 Auke Bay Fisheries Laboratory, National Marine 

 Fisheries Service, Auke Bay, Alaska, in the spring 

 and summer of 1969 and 1970 in the southeastern 

 Bering Sea. The larvae were collected during 

 studies of migrating salmon and exploratory fish- 

 ing for shellfish. In this report, I describe the 

 distribution and relative abundance of the king 

 crab larvae in the southeastern Bering Sea in 

 1969 and 1970 and relate seasonal changes in the 

 distribution of the larvae to current patterns. 



The only reports on distribution and abundance 

 of king crab larvae in the study area are those 

 by Takeuchi (1962, 1968) and Rodin.^ Takeuchi 

 sampled with various types of plankton nets from 

 Japanese crab processing ships off the Black Hills- 

 Port Moller area in 1957, 1958, and 1960. He 

 found more king crab larvae off Port Moller than 

 the Black Hills area, but because his sampling 

 was restricted in area, he could not determine 

 where the larvae had been released or where they 

 dispersed. Rodin's study encompassed a greater 

 area than Takeuchi's but was of shorter duration 

 (less than 1 mo as compared with an average of 

 nearly 2 mo). Rodin speculated, however, that 

 king crab larvae were released primarily in the 

 Port Moller area. 



'Auke Bay Fisheries Laboratory, National Marine Fisheries 

 Service. NOAA, P.O. Box 155, Auke Bay, AK 99821. 



^Rodin, V. E. 1966. Soviet investigation in 1965 to deter- 

 mine the status of king crab (Paralithodes camtschatica 

 (Tilesius)) stocks in southeastern Bering Sea. Unpubl. 

 manuscr., 12 p. Auke Bay Fisheries Laboratory, National 

 Marine Fisheries Service, NOAA, Auke Bay, AK 99821. 



My study provided further evidence that a 

 major area of release of king crab larvae occurs 

 in the Black Hills-Port Moller area and the larvae 

 generally disperse northeastward along the 

 Alaska Peninsula toward the head of Bristol Bay. 



MATERIALS AND METHODS 



A total of 249 plankton tows were made in the 

 southeastern Bering Sea from May to September 

 1969, and 237 were made from March to Septem- 

 ber 1970. Ten-minute oblique hauls were taken 

 from the bottom to the surface during daylight 

 with paired bongo nets (Posgay, Marak, and 

 Hennemuth, 1968), each with a mouth area of 

 0.03 m^ and nylon netting of 0.333-mm mesh. 

 Tows were made at a speed of about 3 knots 

 without regard to tide stage. The plankton 

 samples were preserved in d'vc Formalin^ and sea- 

 water immediately after they were collected. 



Although flowmeters were inside each sampler 

 to determine the amount of water strained, 

 mechanical difficulties prevented an accurate 

 measure for most tows. However, the data have 

 been converted to numbers of larvae under 10 m^ 

 of sea surface, as an index sufficiently precise to 

 determine the general distribution and relative 

 abundance of the larvae. Because the correlation 

 between the two nets fished simultaneously was 

 high (r = 0.979) and it is desirable to use whole 

 numbers, I summed the catch of the two nets in 



■'Reference to trade names does not imply endorsement by 

 the National Marine Fisheries Service, NOAA. 



Manuscript accepted October 1973. 

 FISHERY BULLETIN: VOL. 72, NO. 3, 1974. 



