. Haemoglobins and 17 enzymes in white muscle, terns are diagnostic for this species relative to S. vivi- heart, , and liver were analysed. The enzymes were parus and S. marinus. All species could be group identified by histochemical staining procedures. S. uivi- identified by the use of frequency distributions of IDH parus was identified by phenotypes of malate dehydro­ (liver) and ME (all tissues) phenotypes. genase (MDH) in all tissues, isocitrate dehydrogenase (IDH) in eye, and malic enzyme (ME) in liver. To Kjell Nedreaas: Institute o f Marine Research, P.O. Box 1976, Nordnes, N-5011 Bergen, Norway. Gunnar Nœvdal: Depart­ identify individual specimens of S. mentella, blood ment o f Fisheries Biology, University o f Bergen, P.O. Box samples are needed because only the haemoglobin pat­ 1839, Nordnes, N-5011 Bergen, Norway.

Prey partitioning among juvenile with particular reference to the (Abstract)

S. I. Rogers and J. Jinadasa

One aspect of a study of recruitment mechanisms in the ted, with harpacticoid , cumaceans, amphi- Dover , Solea solea (L.), has examined the feeding pods, and remains present in all length of juvenile stages, and in particular the possibility of groups. Although the majority of prey items found were interspecific competition on nursery grounds. Certain present in the stomachs of both species, the quantities coastal areas of the Irish Sea are nursery grounds for in which they occurred were sufficiently different to juvenile flatfish, including species such as the sole, avoid direct competition. An analysis of the mean prey Pleuronectes platessa, dab Limanda limanda, and the size and mouth size of both species indicated that the solenette Buglossidium luteum. The plaice and dab seem sole had a larger relative mouth size than the solenette, to be largely visual, and possibly also daytime feeders, and that this may have enabled certain large prey while the sole and solenette are non-visual nocturnal species, such as , bivalves, and bivalve feeders. To examine whether any competition for prey siphons, to be included in the diet. The relatively greater items occurred between the sole and solenette in the intestine length of the sole may be an adaptation related first few months of life, the stomach contents of young to the need to digest the plant material consumed by fish were examined in 5 mm length groups, up to a these fish. Differences in jaw morphology between the maximum total length of 60 mm for sole and 50 mm for two species, involving a greater curvature of the jaw solenette. The most abundant items in the stomachs of bones in the sole, also suggested a greater specialization soles were polychaetes, copepods, and plant material, in this species, probably related to the predominantly with small bivalves and the siphons of older individuals infaunal feeding habit. also common in all but the smallest fish. Sand grains, possibly from the tubes of sedentary polychaetes, were S. I. Rogers: Ministry o f Agriculture, Fisheries and Food, Directorate o f Fisheries Research, Fisheries Laboratory, present in stomachs from all length groups. In the Benarth Road, Conwy, Gwynedd, LL32 8UB, Wales. J. Jina­ solenette the range of items in the diet was more restric­ dasa: University o f Sri Jayewardenepura, Nugegoda, Sri Lanka.

Dispersal, growth, and condition of juvenile pelagic cod (Gadus morhua L.) in southwestern Nova Scotia (Abstract)

Iain M. Suthers and Kenneth T. Frank

Larval cod (< 10 mm) and pelagic juvenile cod gear. In each year the spatial distributions of larvae (>10 mm) were each sampled in May 1985-1987 off and pelagic juveniles coincided and were located in a southwestern Nova Scotia by small and large sampling northerly direction from Browns Bank - the main cod

466 spawning area, and consistent with the direction of the age specific growth rates were not significantly different residual circulation. Significant interannual variation in between Browns Bank and the inshore area. Pre­ the percentage of catch remaining near Browns Bank liminary analyses of the otolith daily growth increment was observed, ranging from 5 to 54%. Abundance in widths also suggest no growth advantage of cod in the the coastal environment (< 50 m depth) also varied coastal environment. We suggest that variable duration between years, ranging from less than, to threefold of the Browns Bank gyre, larval drift, and juvenile greater than the offshore. Age and size of pelagic juv­ retention may account for these observations. enile cod differed significantly between the inshore and the offshore areas during three cruises in May 1985, Iain M. Suthers and Kenneth T. Frank: Department o f Biology, Dalhousie University, Halifax, Canada, and Marine Fish Divi­ 1986, and June 1986 (maximum difference of means: sion, Bedford Institute o f Oceanography, Dartmouth, Nova 5 mm, 18 d) although cod were not always younger on Scotia, Canada. Browns Bank. A morphological condition index and

467