Soupfin Shark - Galeorhinus Zyopterus
Soupfins are recognizable by the pronounced spiracles behind each eye and
the over sized terminal caudal tab. It reaches a length of about 6' feet
and is a coppery-bronze to brownish gray in coloration, paler below.
Common off the California coast. Range extends from British Columbia to
Soupfins are a coastal species usually captured in 10-50 fathoms, except in
nursery areas which are believed to be in large sheltered bays. Some
evidence suggests that they have deep water capabilities, as there are
recorded commercial captures at 225 fathoms. Feeds on wide variety of prey
items. Soupfins have been described as benthic blue sharks. They are known
to feed on squid, sardines anchovies as well as flat fish like sand-dabs
and halibut. Soupfins appear to move north in the summer and southerly in
the fall and winter but this is very tentative. In the north males are
more abundant throughout the year while females are predominant in the
Reproductive development is oviparous. Males are believed to mature at
approx. 60" inches, females at around 70" inches. Some mating is known to
take place in the spring and gestation is believed to be about 12 months.
Pups are born around 1 foot in length. Litters can range from 6 to 50 pups
with the average being 25 to 30. While most of the nursery areas are
believed to be south of Pt conception there are important nursery areas in
the San Francisco, Humbolt and Tomales bays.
Historically regarded as California's #1 shark fishery there is a well
established market for soupfin shark as a source of thick steaks and dried
fins, moreover, there was a long standing liver market which crashed due to
resource depletion shortly after world war II.