Family Clupeidae - herrings
The herring family is very important to commercial fishers and the oceanic food web. Herring once caught are processed by pickling, smoking, canning or salting. Although most species are marine, some spawn in fresh water and others only occur in fresh water. This widely distributed family can be found in all seas except the Arctic and Antarctic.
American shad- Alosa sapidissima
Remarks: This is the largest herring of the Pacific; introduced to the west coast during the late 1800s. Anadromous in nature and forms large schools especially when migrating. Although it is never found in abundance within the bay and does not migrate up bay tributaries.
Identification: Unmistakable by itÍs bright silver coloration and deep body form. There is a row of strong sharp scutes along the belly. A line of spots from the top edge of the gill cover to the end of the dorsal fin adding to the uniqueness of this fish.
Range: Alaska to southern California; making strong runs into the Sacramento and San Joaquin river systems.
Pacific herring- Clupea harengus pallasii
Remarks: This was one of the last fish to become commercially important but has remained valuable. First taken in the bay as an experimental catch which proved excellent smoked. Soon large catches of herring were made and became an important export. Today the herring is still fished but most recently for itÍs highly desirable roe. The fish are caught for their roe in the winter months when they come into the bay to spawn on the eel grass beds. Timing is most important in this fishery because the fish must be caught when they are in thick schools and laden with eggs.
Identification: Spots are absent on this herring and it is bluish above with silvery sides leading to a paler belly. Body is elongate and compressed side to side. May reach a length of 46cm.
Range: Common in coastal zones but forms larger schools in the offshore zones from Alaskan waters to northern Baja.
Threadfin shad- Dorosoma pentenense
Remarks: This herring-like the American shad was introduced into California in the 1950s primarily as a forage fish in reservoirs. Seldom seen in the bay but its occurrence may increase as itÍs range expands.
Identification: Distinct by having a very compressed body with a long trailing dorsal fin ray. A single spot behind the upper edge of the gill operculum and an overall silver color make this fish identifiable.
Range: While it mostly inhabits freshwater environments the threadfin shad is found in many bays and estuaries throughout California and Oregon.