FISHERY BULLETIN: VOL. 71, NO. 2 



Figure 6. — Distribution and abundance of sand lance larvae in the May cruise in shallow (left) and 



deep (right) tows. 



Norcross et al. (1961) found no sand lance 

 larvae off Chesapeake Bay in salinities lower 

 than 30"/oo, yet Wheatland (1956) found them 

 in Long Island Sound in salinities as low as 

 24.2'Voo. Croker (1965) found them in Sandy 

 Hook Bay below 28.6'7oo. and studies from 

 Delaware Bay indicated larvae occurred in 

 water of 4.3*Voo to less than 1.8'Voo salinity 

 (Norcross et al., 1961). Plankton distribution 

 was similar to that of the larvae; inshore and 

 offshore volumes of 100 to 200 ml/tow were 

 separated by a low volume strip of 55 to 

 100 ml/tow. Thus, food was available for both 

 inshore and offshore groups off Long Island 

 and New Jersey. Although plankton abundance 

 was as great off Chesapeake Bay, we found 

 no sand lances in this area. 



Distribution and Movements of 

 Larvae of Different Sizes 



Figure 7 shows the length frequencies of 

 sand lance larvae for each cruise, and Figures 



8, 9, and 10 depict the distributions of five 

 size groups (between 4 and 60 mm). Table 4 

 gives the depth distribution of these size groups 

 by night and by day. Larvae were seldom taken 

 in deep water tows only, but in many instances 

 they occurred only in tows above 15 m. All 

 larvae collected in December were 4 to 8 mm 

 long. 



The total length range generally increased 

 during the spring (Figure 7), and as larvae 

 grew they dispersed away from the coast and 

 decreased in apparent abundance (Figures 8 

 to 10; Table 4). The greatest number of those 

 of small size occurred inshore at the northern 

 end of the range of these cruises in late fall 

 off Martha's Vineyard and eastern Long Island. 

 Some also appeared in early winter near 

 Delaware Bay. However, lack of many early 

 winter collections, selectivity of the 0.5-mm 

 mesh of the Gulf V sampler, and the hatch 

 from demersal rather than pelagic eggs lowered 

 the chance of sampling the smallest size group 

 in proportion to their abundance. The greatest 



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