485 



Dow, Robert L. 1952. 



Shellfish survey methods. Convention addresses, Natl. Shellf. Assn.: 

 1-9. 



Three Venus surveys made by plane table gave an average production of 

 1,508.83 bu/acre, with a range of error of minus 3.7 to plus 9.0%. Total 

 acres was 15.4, and averaged estimated volume/acre was 1,563.83 bushels. 

 - J.L.M. 



486 



Dow, Robert L. 1953. 



An experimental program in shellfish management. Maine Dept. Sea Shore 

 Fish., Fish. Circ. 10, 11 p. 



Describes in some detail the steps followed in a successful clam management 

 program in the Town of Wells, Maine. Social-political actions, scientific 

 surveys and studies, and management measures are detailed. The species is 

 not identified, but the name clam in Maine means My a arenaria . - J.L.M. 



487 



Dow, R. L. 1954. 



Problems of polluted shellfish growing areas. Paper presented to Am. Soc. 

 Civil Eng., 5 Nov. 54, 8 mimeo . p. 



488 



Dow, R. L. 1955. 



Infra and intra-tidal sets of Venus in Maine. U.S. Fish Wildl. Serv. , 5th 

 Ann. Conf. Clam Research: 33. 



Commercially important sets of hard clam in intra-tidal areas have not 

 often survived in Maine. The commercial fishery is limited to a portion 

 of Casco Bay in the intra-tidal zone. Evidence from dredging operations 

 showed that clams of all year classes from 1940 to 1951 inclusive, except 

 19 50, had survived below low tide in Maquoit Bay, and those of all year 

 classes from 1942 to 1951 inclusive, except perhaps 1945, had survived in 

 Middle Bay. - J.L.M. 



489 



Dow, Robert L. 1958. 



Sanitary criteria for shellfish by species and by area. Proc. Natl. Shellf. 

 Assn. 48: 23-29. 



To implement recommendations of the 19 54 National Shellfish Sanitation 

 Conference studies were conducted in Maine to evaluate the relative 

 importance of hydrographic, geological, and biological factors in their 

 influence on sanitary quality of shellfish growing areas. Among biological 

 factors it was noted that where soft clam and hard clam (Mercenaria 

 mereenaria) occurred in commercial concentrations in an area, hard clams 

 were invariably found in places where the overlying waters were of high 

 salinity. Thus, quahogs are less subject to contamination than soft clam 

 in the same growing area. Because it can close its valves completely, 

 whereas soft clam cannot, hard clam is less exposed to contamination from 

 brief exposure to polluted fresh water. Soft clams stored alive will live 

 only from 1/2 to 1/5 as long as hard clams. These biological differences 

 mean that the same sanitary requirements should not apply to different 

 shellfish species. - J.L.M. 



135 



