Alosa sapidissima

Common Name

American Shad

Year Described

Wilson, 1811

Identification

Dorsal Fin: 14-21
Anal Fin: 18-25
Pectoral Fin: 13-18
Pelvic Fin: 8-10
Vertebrae: 55-57
Scales: 52-62 (transverse rows)
Ventral Scutes: 35-38
Gill Rakers: 59-73 (lower limb first arch)

Body fusiforme and compressed. Depth of body quite variable with size. Ventral profile extremely convex from pelvic fin to lower jaw. Head moderate. Snout equal to eye diameter. Mouth large, extending to rare margin of eye. Upper jaw distinctly notched (unique to Brevoortia, Alosa, and Dorosoma. Lower jaw fits into upper jaw notch, does not project beyond upper, and does not rise steeply within the mouth. Teeth absent in jaws (adults). Dorsal fin at midbody with a strongly concave margin. Anal fin origin well behind last dorsal ray. Pelvic fin under dorsal fin. Pectoral fin low on side. Tail forked. Body fully scaled. Pre-dorsal scales not enlarged, modified, or fringed. Axillary scale of pelvic fin about half fin length. Belly scutes keeled.

Color

Metallic green to blue above, grading to bright silvery on the sides and belly. A dark blotch is present posterior to the upper opercular margin. Several smaller, fainter spots may be present posterior to this blotch. The dorsal and anal fins may be dusky or clear.

Size

Maximum size 60cm SL, but common to 50cm SL.

Habitat

Adults found at sea in coastal waters. Anadromous: spawns in freshwater and young return to saltwater.

Range

Newfoundland to east-central Florida.

References

Hildebrand, S.F. 1964. Engraulidae and Clupeidae (pp. 152-454). In: Fishes of the Western North Atlantic. Mem. Sears Fnd. Mar. Res. 1 (Vol. 3): 1-630.

Munroe, T.A. & M.S. Nizinski. 2002. Clupeidaeidae (pp 804-830). In: Carpenter. 2002. The living marine resources of the Western Central Atlantic. Vol. 2: Bony fishes part 1 (Acipenseridae-Grammatidae). FAO Species Identification Guides for Fisheries Purposes. American Society of Ichthyologists and Herpetologists Special Publication No. 5.

Other Notes

A related species living on the Gulf coast is Alosa alabamae.