Gizzard Shad


Gizzard Shad - Dorosoma cepedianum

*Information from FAO Species Identification Guide Western Central Atlantic*

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Size
Maximum 42 cm standard length; commonly to 30 cm standard length.
Habitat, biology, and fisheries

Inhabits mainly freshwaters, found in large rivers, reservoirs, lakes, swamps, temporary floodwater pools, and estuaries; larger fishes tolerating salinities up to 41.3‰. In brackish water populations, young remain in fresh water until reaching about 70 mm total length. Herbivorous, filter-feeding on microscopic plants (at least in fresh water); food is strained by the numerous fine gill rakers, then presumably transferred in a mucus stream in the pharyngeal pouches, concentrated in some way, then everted as abolus into the pharynx.  Spawns in fresh water from mid-March to August in ponds, lakes, and large rivers, usually near surface depths (0.3 to 1.6 m) but sometimes as deep as 15 m;daylight spawning typical, but nighttime spawning observed in Alabama; eggs adhesive and demersal; experience heavy post-spawning mortality. Fecundity 22,400 to 543,900 ova. Prone to large-scale, unexpected die-offs in late summer. Separate statistics not reported for this species. Frequently caught in brackish bays, estuaries, and rivers, mainly with seines. Valued as a forage for various game fishes, not esteemed as food, but sometimes used as fertilizer and harvested for its oil, utilized as a supplementary food for pigs or cattle.

Distribution
Atlantic coast (New York to Florida) and Gulf of Mexico, southward to central Mexico; also Atlantic and Gulf of Mexico drainages of North and Central America, southward to the Mississippi river drainage and smaller rivers affluent to the Gulf of Mexico southward to the Río Pánuco, Mexico.