89 



Infection by Monas may seriously reduce a culture in a short time, but when 

 a Phaeodaotylum culture is f ast-growing, Monas is not a problem. Harvesting 

 and direct use of the phytoplankton crop presents problems, but feeding the 

 culture to Meroenaria (Venus) meroenaria, which can filter up to 2 liters 

 of water/hr, and is high priced, may solve the problem. - J.L.M. 



Ansell, Alan D. 1963. 



Seafood from industrial waste. Sea Frontiers 9(3): 178-185. 



In England, CO2 from flue gas of an electric generating plant, water, simple 

 inorganic salts, and sunlight were being used to grow cultures of Phaeo- 

 daetylum trioornutum as food for Venus meroenaria in laboratory experiments. 

 Most efficient use of phytoplankton was obtained when it was added to the 

 water in low concentrations. Questions still needed to be answered before 

 full-scale pilot plant operations would be feasible. - J.L.M. 



Ansell, A. D. 1963. 



The biology of Venus meroenaria in British waters, and in relation to gen- 

 erating station effluents. Ann. Rept. Challenger Soc. 3(15): 38 (abstract). 



V. meroenaria is distributed throughout Southampton Water in southern England 

 and has been recorded from Portsmouth Harbor and the Newtown estuary. Isle of 

 Wight. Centers of maximum population density are Netley, Marchwood, and 

 Millbrook Point. Annual growth in length and weight is greatest in warm 

 water from Poole generating station. Clams there begin growth earlier in the 

 season and continue later. Differences in salinity or substrate type did not 

 appear to affect growth. In warm effluents clams came into condition earlier 

 in the season and reached spawning potential earlier. The peak was main- 

 tained slightly longer than at other sites, but spawning potential fell off 

 in July, remaining high elsewhere. In British waters V. meroenaria behaves 

 like an animal near the northern limit of its range. Effects of warm 

 effluents change this response to one typical of more southerly areas. Great 

 potential advantages were seen in controlled use of warm effluents. - J.L.M. 



90 



Ansell, Alan D. 1963. 



Venus meroenaria (L) in Southampton Water. Ecology 44(2): 396-397. 



Venus meroenaria had been known to occur in Southampton Water, the estuary 

 of the River Test in southern England. It also is found in the Solent, the 

 strait between Southampton Water and the Isle of Wight, and in Portsmouth 

 Harbour to the east. It is well established in the area, growth is rapid 

 in some places, and the species produces a spatfall in some years. The 

 detailed distribution is described. Clams placed in a laboratory tank, 

 from an ambient natural temp of 16°C to 18.6°C, spawned. Clams have 

 spawned in the laboratory at temps between 17.8 and 26.9°C with and without 

 stimulation by sperm suspension. Clams which spawned at 17.8°C had never 

 been in temps higher than 18°C and had been exposed to a rise of only 2°C 

 before spawning. This is lower than ever before reported and suggests that 

 the species has become acclimated to local temps, which rarely exceed 22°C. 

 Fertilized eggs have developed into straight-hinge veliger larvae within 

 48 hrs at 19° to 21°C and have been brought to setting, typically in 13 

 days after fertilization. Clams have been estimated from shell rings to be 

 5+, 9+, and 12+ yrs old, suggesting setting in 1955, 1951, and 1948. Age 

 distribution varies somewhat with locality. Size -frequency distributions are 

 given for three areas. The origins of these clams are obscure. Experimental 

 introductions have been made in Great Britain, but none is known in the 

 Southampton area. It is suggested that accidental introductions via the 

 galleys of transatlantic vessels is most likely. The time of introduction 

 is not known, except that it was prior to 1948. Successful establishment 

 and spreading may have been assisted by warm water from many industrial sites 

 in the area. - J.L.M. 



24 



