Stillhead
Posts: 3377
Joined: 12/19/2003 Status: offline
|
Herrings Family Clupeidae Family overview: The herrings are primitive, bony fish. The family Clupeidae dates back 120 million years. Worldwide the family includes about 200 species, including sardines, anchovies, menhaden, shad and herrings. Most herring family species are ocean-dwelling or anadromous, living in salt water as adults, but returning to fresh water to spawn, and spending the early part of their lives in fresh water. Other herring family members are strictly freshwater fish. Pennsylvania is known to have, or have had, six species of herrings. Skipjack herring have been reported by creel checks in angler catches. This species occurs in the Ohio River, near Pittsburgh. The skipjack looks much like the uncommon hickory shad, which has been reported in the lower Delaware River. Other herrings in Pennsylvania are the blueback, alewife, American shad and gizzard shad. The herrings can be found in the Delaware River and its estuary, especially during the spawning migration. Some (especially the American shad) are appearing in the Susquehanna River watershed because of fish lifts on dams and stocking. Other herring family members live in western Pennsylvania, in the Lake Erie and Ohio River watersheds (gizzard shad). The alewife has been introduced into larger reservoirs in the state as a forage species for large game fish. Identification: Very young herring are long and slender, much different from the adults. Adults of the herring family are deep-bodied when viewed from the side. They are extremely compressed and flattened when viewed head-on. They have large, brilliant-silver scales, which are cycloid, smooth to the touch, and easily shed when touched. There is one soft-rayed dorsal fin in the center of the back, and the tail is deeply forked. The eye is large. There are no scales on the head, and no lateral line on the sides. The scales on the midline of the belly are modified and have sharp points. These “scutes” give the belly a rough, saw-toothed edge. They account for several herring species’ common name of “sawbelly.” Life history: Most herrings are pelagic–they are midwater forms not associating with bottom structure. Herrings are school fish and can occur in very large concentrations. All spawn in the spring, some migrating great distances from the adult’s marine home, swimming upstream many miles into freshwater rivers. Other herrings spawn in tidal, brackish bays, or in the shallows in freshwater lakes. Herrings produce a large number of eggs for their size. A 12-inch, one-pound gizzard shad, for example, can hold 250,000 eggs at maturity. Schools of herring, the males and females pairing, scatter adhesive, fertilized eggs over various bottom types, including the rocky riffles of rivers and the pebbled shoals of reservoirs. There is no nest-building or parental care. Herrings eat mostly zooplankton, tiny aquatic animal life. The larger species may also eat shrimp, fish eggs and fry. Herrings grow rapidly and are not long-lived. http://www.fish.state.pa.us/pafish/fishhtms/chap10.htm
|