 Walleye Surfperch (Hyperprosopon argenteum)
 Distribution of walleye surfperch in San
Francisco Bay
Walleye surfperch range from Vancouver Island, British Columbia to Baja California.
They are abundant along sandy beaches, over areas of flat rock, and around piers.
They live to six years and reach a maximum length of 300 mm. Walleye surfperch are
one of the most commonly caught Embiotocids in both the commercial and sport fisheries
along the California coast.
As with all Embiotocids, walleye surfperch are viviparous. Mating occurs in the fall
or winter, with a gestation period of five to six months. In May and June, females
immigrate from the nearshore coastal area to shallow areas of Bay to give birth.
Juveniles apparently rear in the Bay for only two to three months before emigrating
to the ocean. Walleye surfperch mature in the fall or winter of their first year.
Major food items for juvenile and adult walleye surfperch include small crustaceans,
polychaetes and gastropods. They are preyed upon by kelp bass, sculpins, and halibut.
Abundance indices of young-of-the-year (YOY) walleye surfperch have been low since
1990, although indices were also very low in 1985, 1986, and 1988. Although we do not
know what factors control abundance of walleye surfperch in the Bay, low fecundity
combined with the seasonal migration of females to shallow areas to give birth could
make them vulnerable to overfishing.
Annual abundance indices
for YOY walleye surfperch are generated from the San Francisco
Bay Monitoring Program using midwater trawl data.
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