Gizzard Shad (Dorosoma cepedianum) - Native
A 19-inch adult gizzard shad.
Identification. Deep body. Small head and mouth. Snout short and blunt. Last dorsal ray greatly elongated. Single faint spot on shoulder. Scales small and irregular in places. Long anal fin (25-36 soft rays). Typically gray to brown on back fading on sides to almost white on belly. Tends to be very slimy. Typically not as silvery as other herring; some adults very dark overall.
A 6-inch juvenile gizzard shad displays the short snout and elongated dorsal ray that are characteristic of the species.
Size. Commonly 6 to 18 inches. State survey max. size 21 inches. Max. reported size 22 inches. World Record 4.4 pounds.
Distribution. Widespread in fresh waters of the United States from the Mississippi drainage eastward. Anadromous populations exist along the Middle Atlantic Coast, but none have been documented in Connecticut. Freshwater populations are established in all three of Connecticut’s major river systems (Housatonic, Connecticut and Thames) and fish are using some fishways to expand upstream of barrier dams.
All maps created in 2009. See CT DEEP Fish Community Data for updated distributions.
Habits. Like all herring species, gizzard shad are schooling fish. They prefer quiet areas of large rivers and estuaries, but may occasionally enter marine waters. They are typically common where found. Gizzard shad feed almost entirely by filtering phytoplankton from the water. For this reason, anglers rarely and only accidentally catch them. They spawn near the surface during mid- to late spring. Little is known of their life history in Connecticut.
Comments. Gizzard shad were first observed in Connecticut during the late 1970s, apparently the result of a natural range expansion, probably from Hudson River stock. The species became well established in all of our larger coastal rivers during the 1980s, and populations may still be increasing. It is unclear how this recent expansion may be affecting other fish communities. Because adult gizzard shad are large, they are probably not as heavily preyed upon by striped bass as are other herrings.
Text and images adapted from Jacobs, R. P., O'Donnell, E. B., and Connecticut DEEP. (2009). A Pictorial Guide to Freshwater Fishes of Connecticut. Hartford, CT. Available for purchase at the DEEP Store.