A member of the Clupeidae family of herring and shad, the gizzard shad is important forage for large ﬁsh. However, its rapid growth rate causes it to exceed a consumable size for most predators early on in its life. It is often labeled a nuisance ﬁsh by anglers and biologists, due to large die-offs, which happen because the species is especially susceptible to drastic changes in temperature and low concentrations of oxygen.
IdentificationThe gizzard shad is one of two freshwater members of the herring family that has a distinctively long, slender last ray on its dorsal ﬁn. The body is silver blue on the back and silver white underneath, with either blue-and-green or gold reﬂections on the head and the ﬂanks.
Occasionally, there are six to eight horizontal dark stripes on the back, starting behind a large purple blue or black shoulder spot (which is faint or absent in large adults). The gizzard shad also has dusky fins, a blunt snout, a subterminal mouth, and a deep notch at the center of the upper jaw.