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Deepseawaters Home Deepsea
AnimalsAngel Shark
Angel Shark
Common Name: Angel Shark
Scientific Name: Squatina Spp
Description
 With
its exceptionally flat body and large pectoral fins, the angel
shark resembles a large ray more than a shark. Its skin is
grey to reddish or greenish-brown,
scattered with small white spots and blackish dots. Young
angel sharks may also have white net-like markings and large,
dark blotches, whilst adults are plainer. The dorsal fins
have a dark leading edge and a pale trailing edge. It possesses
simple, whisker-like projections near the nostrils, (nasal
barbels), which are used to taste and feel. Large, round eyes
with vertical slit pupils provide good all-round vision, enabling
the angel shark to be an efficient ambush predator.
Diet
Angel
sharks to eat small fishes, crustaceans, mackerel,
croaker and molluscs.
Behaviour
Pacific
angel shark are usually found lying partially buried
on flat, sandy bottoms and in sand channels between rocky
reefs during the day, but they may become active at night.
Tagged specimens near Santa Catalina Island
were found to move from a few feet to four nautical miles
per night. However, individual sharks have been observed to
remain in the same place with no apparent movement for up
to 10 days.
Sexual
maturity in both males and females occurs between 35 and 39
inches total length. Embryos present per female range between
one and 11, with a mean of six pups produced annually from
March to June. A 10-month gestation period was estimated for
this species.
Habitat
Pacific
shark, in difference to many species of sharks, is
bottom dweller. It buries itself in sand or mud bottoms during
the day, coming out to vigorously search for food at night.
It is frequently found on the continental sill and littoral
areas, and sometimes hang out near rocks, canyons and kelp
forests. The adults are semi-nomadic, moving to new locations
after expenditure days in a partial area. Although they normally
occur alone, this species may be found in cumulative
Special
Features or Habits
Several
techniques have been utilized in an effort to age angel sharks,
but to date aging this species has been unsuccessful. Researchers
have observed that angel sharks are born with six to seven
bands in their vertebral centra, but growth curves based on
size and band counts were found to be atypical. Both centrum
edge histology and size-frequency analyses have proven inconclusive.
Sharks grown in the laboratory, along with field-tagged, tetracycline-
injected returns, indicated no periodic basis for band deposition
in the vertebrae, but indicated that calcified band deposition
is more related to rapid somatic growth
Location
or Region Found
The
Pacific angel shark is reported to occur
only in the eastern Pacific Ocean from southeastern
Alaska to the Gulf of California and from
Ecuador to Chile. A gap in distribution
separating subpopulations of S. californica occurs between
the equator and 20° North latitude. The southern population
was earlier reported as a separate species, S.armata.
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