nia to develop methods of growing the Dungeness 

 crab. Cancer nuii^ister, using locally produced fish 

 wastes as food. The studies are being conducted in 

 two different environments in Humboldt Bay, in 

 pens — one using heated effluents from an electric 

 power plant and the other in bay ponds at ambient 

 temperatures. The diet preference, condition, and 

 growth are determined and evaluated. This project 

 could provide a cheap source of food for an aqua- 

 culture operation as well as make use of what is 

 now a waste disposal problem. Early results indicate 

 that a food mixture of rockfish, sablefish, Dover 

 sole, and shrimp offal produced the best results. 



Research is underway at Hast Carolina University 

 on the reproductive cycles and fungal parasites of the 

 blue crab and will begin shortly on the American 

 lobster, Honuinis cuncikaniis. Studies to date on 

 the crab have included observations of the condition 

 of the ovary as seen through the carapace, condition 

 of eggs of ovigers, and occasion of spawning by 

 certain individuals. The crabs which ovulated were 

 successfully induced to attach their egg mass, some- 

 thing not previously reported for the blue crab. At- 

 tempts to date to isolate La^enidiiim callinectes or 

 other fungal parasites of crab eggs have 

 been unsuccessful. 



In laboratory studies at Texas A&M University 

 with young blue crabs (5-40 mm), a sand plus oyster 

 shell substrate supported significantly better survi- 

 val than did either sand alone or bare glass. The 

 suitability of various temperatures and salinity levels 

 were also evaluated. 



Lobster 



One of the most highly prized seafood organisms 

 in the world, the American lobster, Homcinis 

 anii'iicuniis, is being studied by geneticists at the 

 University of California at Davis. The intent is to 

 develop the technology necessary to grow large 

 numbers of edible quality lobsters, to marketable 

 si/.e, in a short period of time, at less cost than the 

 market value. The project is being conducted in 

 cooperation with the State of Massachusetts Lob- 

 ster Hatchery on Martha's Vineyard Island. The 

 work includes the improvement of culture facilities; 

 development of an economically feasible form of 

 tood; studies of the effect of selected environmental 

 parameters on growth; application of genetics tech- 

 niques for the selection of fast growing lobsters: 

 cvakialion of biochemical methods for controlling 

 cannibalism, mating, molting, and disease ; and phys- 

 ical methods to control cannibalism. Research, al- 



ready completed has shown that it is possible to 

 produce a 1 pound (0.45 kg) lobster in 2 yr time 

 instead of the 7-8 yr it takes in the sea, by growing 

 them at 20°C and feeding them daily. 



Work on the American lobster at the University of 

 Rhode Island is also directed toward reducing the 

 time required to grow the animal to market size. 

 Here the effort has resulted in the development of 

 methods for accelerating the hatching of eggs and the 

 mass culture of larvae to juveniles under controlled 

 conditions. Work is now in progress for maximizing 

 the growth rate of juveniles to market size under 

 optimum conditions. 



Several parts of a multifaceted program of re- 

 search at San Diego State College on spiny lobster, 

 Pdniiliriis iiuerniptiis, and American lobster involve 

 aquacultural work. Juveniles of spiny lobster have 

 been studied with respect to the effects of elevated 

 temperatures (20°. 22°, 26°, and 28°C) on growth and 

 metabolic energy budget. Studies of American lob- 

 ster in progress are providing a comprehensive evalu- 

 ation of the biological and economic feasibility as 

 well as the potential benefits and dangers of estab- 

 lishing this species as a fishery resource in California 

 waters. Part of this work is concerned with develop- 

 ing and evaluating lobster culturing techniques, with 

 the primary aim of producing large numbers of young 

 suitable for stocking. 



Crayfish 



In a project to develop crayfish culture in the 

 Pacific Northwest, biologists at Oregon State Uni- 

 versity are developing husbandry methods in con- 

 trolling environments. A system for holding and 

 breeding adult crayfish in captivity has been de- 

 veloped. 



Juveniles are raised singly in small cells to avoid 

 cannibalism of soft-shelled animals. Several natural 

 and artificial diets have been tested and research on 

 nutrition is now centered around a simulated natural 

 diet versus a high protein vegetable pellet diet. The 

 role of temperature and salinity on growth and sur- 

 vival is also under study. 



MOLLUSCS 



Oysters 



In a large multidisciplinary effort, scientists at the 

 L'niversity of Delaware are working to improve our 

 techniques in shellfish culture. .\ variety of prob- 

 lems are being attacked in both open and closed 

 'ulture systems. Over 500 million oyster larvae were 



44 



