middle, southern, and gulf coasts of eastern North 

 America (Megrey 1979). Landlocked freshwater 

 populations are known from the Mississippi River 

 drainage (Miller 1956; Megrey 1979) and the Great 

 Lakes (Miller 1956, 1960). On the North American 

 Atlantic coast, the gizzard shad has been reliably 

 reported north to northern New Jersey and New 

 York Harbor (Breder 1938; Miller 1956) (Fig. 1). 

 Recent evidence indicates that the gizzard shad 

 has ventured into the estuaries of certain major 

 rivers draining into Long Island Sound. Dew (1974) 

 reported that the species was first observed in the 

 lower Hudson River estuary at Indian Point (river 

 km 64.5) between 1969 and 1971 (Fig. 1). Subse- 

 quent surveys suggested that the lower Hudson 

 River population is increasing and that reproduc- 

 tion was possibly occurring in the estuary (Dew 



1974). However, George (1983) believed that the giz- 

 zard shad in the lower Hudson River are derived 

 from fish which migrated through the Erie Canal 

 to the Mohawk River and down the Hudson River. 

 If George's (1983) theory is correct then the lower 

 Hudson River population would have been founded 

 by landlocked freshwater animals, and not by mi- 

 grating "anadromous" adventives from New York 

 Harbor. 



Results and Discussion 



In the Connecticut River, adult gizzard shad were 

 first observed near the mouth (river km 2.4, Fig. 

 1) in 1976 by commercial fishermen using gill nets 

 set for American shad, Alosa sapidissima, (Whit- 

 worth et al. 1980). In 1984 and 1985, gizzard shad 



Figure 1.— Recent reports of the gizzard shad, Dorosoma cepedianum, in New England: 1. Whitworth et al. (1980), Connecticut River, 

 river km 2.4. 2. Gephard (text fn. 2), Connecticut River, river km 26. 3. O'Leary and Smith (this paper), Connecticut River, river 

 km 139.4. 4. Gauthier (text fn. 3), Millstone nuclear power plant. 5. S. Henry (Assistant Aquatic Biologist, Massachusetts Division 

 of Fisheries and Wildlife, Field Headquarters, Route 135, Westboro, MA 01581), Lawrence fishway, Merrimack River. 6. O'Leary and 

 Smith (this paper), Connecticut River, Northampton Oxbow, river km 150. 



381 



