depositing eggs in adhesive mats on the sea floor that then 

 develop and hatch in approximately ten days). The ROV Minirover 

 was used together with surface deployed sampling gear to define 

 the extent and density of egg deposition and the nature of the 

 spawning substrate. The egg mat was fairly thick, measuring from 

 1 to 3 cm or from 20 to 30 eggs deep. This is generally thicker 

 than previous reports for the Gulf of Maine, but was not a factor 

 in egg mortality. The percentage of dead eggs in most subsamples 

 was negligible. The successful hatching, despite the high egg 

 density, presumably is a result of the strong water currents and 

 consequent aeration of the egg bed. Substrate type was not 

 clearly a controlling factor in defining egg beds. Distinct egg 

 bed perimeters observed in some locations were defined by changes 

 in substrate; in other locations where egg cover declined more 

 gradually the substrate inside and outside the bed was similar. 

 What was apparent was that gravel is a necessary component of the 

 spawning substrate. The conditions along the eastern Maine 

 coast are optimal for the successful spawning of herring and 

 hatching of the eggs. Egg density reached a high of 7.2 million 

 eggs m-2 on the primary study site. The estimated weight of 

 spawning herring required to produce the quantity of eggs 

 observed was 8,000 to 15,000 metric tons, or 6 to 7% of the 

 estimated spawning stock for the coastal Gulf of Maine stock. 



The two papers on sea scallops are related in that the field 

 work was done on the same scallop beds although the objectives of 

 the studies were quite different. The paper by Berkman utilized 

 manned submersibles to conduct tagging and caging experiments. 

 At two locations in the Gulf, tagged scallops and scallop shells 

 were placed both inside and outside cages. The following year 

 the locations were revisited and the scallops recovered for 

 examination of the epizooic shell community, deterioration of the 

 tagged shells, as well as movement, growth and mortality of the 

 live scallops. Unfortunately, both experimental sites were 

 disturbed by trawling but a significant percentage of the scal- 

 lops and shells were recovered from the Fippennies Ledge area. 

 At this location 58% of the tagged live scallops were recovered 

 in close proximity to the release site. In other words, these 

 adult scallops moved little over the year. They did, however, 

 grow and their growth rate was comparable to other published data 

 on the growth of similar sized animals. What's of particular 

 interest in the paper is the discussion of estimating natural 

 mortality by use of "clapper" shells. Previous reports have used 

 the time for deterioration of the shell ligament to estimate 

 mortality. Berkman' s study found that shell ligaments deteri- 

 orated quite slowly and suggests that shell valves may stay 

 attached longer than previously thought; from as little as 20 

 weeks to over one year. Thus the "clapper" technique for 

 assessing mortality needs to be re-evaluated. Another aspect of 

 the paper was an assessment of the variation in the epizooic 

 shell communities. There was a significant difference in the 

 community that established itself on the inside and outside of 

 scallop shells. Over the year, 55 species settled on the scallop 

 shells and established assemblages with different degrees of 



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