1733 



Stewart, James E.,and H. E. Power. 1963. 



A sea water aquarium for marine animal experiments. J. Fish. Res. Bd. Canada 

 20(4): 1081-1084. 



The aquarium is suitable for holding shellfishes. - J.L.M. 



1734 



Stickney, Alden P., and Louis D. Stringer. 1957. 



A study of the invertebrate bottom fauna of Greenwich Bay, Rhode Island. 

 Ecology 38(1): 111-122. 



Clam investigations of U.S. Fish and Wildlife Service were established by 

 Congress in 1948 under legislation sponsored by Atlantic States Marine 

 Fisheries Commission to study populations of My a arenaria and Venus mercenaria. 

 Water depth in Greenwich Bay is almost uniform at 10 to 14 ft, except for the 

 channel. Bottom is silt to sandy-silt to sand, with shell in some places. 

 Water conditions are typically uniform top to bottom. Max water temp was 26°C. 

 Salinity varied from 27 to 30°/°°. Tidal currents were relatively slow. The 

 Bay proper was relatively unpolluted. Samples were taken with a "clamshell" 

 construction bucket. Venus mercenaria was present in each sector sampled. 

 Abundance varied from 2 to 22 clams/m^ in 1951 and 1 to 24 clams per m* 2 in 

 1952. Hard clam was present in the Ampelisca community, but was present 

 almost everywhere in the Bay. It was less abundant in mud than elsewhere. 

 V. mercenaria also was present in the Crepidula-Nereis-Neopanope community 

 and was more abundant in sand-silt-shell type sediment favored by this 

 community than in any other type of bottom. Mean numbers of fenws/sample 

 (clams over 20 mm) in 1951 were: silty sand plus shell 12 clams; silty sand 6; 

 pure sand 2; and mud 2. A chart shows the distribution and density of Venus 

 in the areas sampled. In the sand bottom community numerous juveniles of 

 Venus and other bivalves settled in certain places in 1952, forming substantial 

 temporary populations. The drill Eupleura caudata was reducing these 

 populations at the time of sampling. Venus also was present in the intertidal 

 zone. It was among the predominant species on stony beaches. A substantial 

 spatfall of Venus was found on most parts of the shore each year. Eupleura 

 caudata, Urosalpinx cinerea, and Neopanope texana are very destructive of 

 young. Eupleura is broadly distributed and does not necessarily congregate 

 where young Venus are numerous, but in 1951 and 1952 the greatest numbers 

 appeared in sector 10, where newly set bivalves of several species were 

 abundant. In 1951 34% of all juvenile Venus taken had been drilled, and in 

 1952 all had been drilled. Drilling is most destructive to the 2 to 7 mm size 

 group of Venus. Those above 15 ran are seldom attacked. Other important 

 predators of Venus were Limulus polyphemus , Callinectes sapidus, Ovalipes 

 ocellatus , Libinia emarginata, Polynices duplicata, and Busycon c anal i cul a turn. 

 Young Venus do not set uniformly over all parts of the bottom ostensibly 

 suitable for them. They may colonize different areas of the Bay each year. 

 This may be caused by concentration of larvae by currents, but to some 

 extent also may be influenced by voluntary movement of newly set juveniles. 

 The muddy central part of the Bay is relatively barren of Venus. No 

 association was observed between distribution of Venus and other species. 

 Some similarity in distribution was noted between Venus and Nereis, but the 

 centers of population of the two did not coincide exactly. Venus and 

 7 other species, by reason of their abundance and broad distribution, were 

 termed characteristic of Greenwich Bay. Venus mercenaria, like Pectinaria 

 gouldii, is distributed intermittently along the New England coast, 

 although the 2 species showed no particular similarities in distribution 

 in Greenwich Bay. In 13 localities between Portland, Me. and Milford, Conn, 

 the 2 species were present in 6 and absent in 6. One locality had Venus but 

 no Pectinaria. At Salem, Mass. lives the only recent population of Venus 

 mercenaria between Boston and Portland, Me. This is also the location of 

 the only population of Pectinaria gouldii known to the authors along the 

 same section of coast. - J.L.M. 



479 



