Coastal Post Online
MARIN COUNTY'S NEWS MONTHLY - FREE PRESS
(415)868-1600 -
(415)868-0502(fax) - P.O.
Box 31, Bolinas, CA, 94924
October, 2004
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Shark Season Arrives In gulf Of The
Farallones
Late summer and
fall are the "Season of the Shark" in the Gulf of the Farallones
National Marine Sanctuary off San Francisco,
as each year white sharks (Carcharodon carcharias) target the waters around the
Farallon Islands to feed on elephant seals and sea lions. The Farallones
sanctuary hosts a significant population of reproductive-age white sharks.
„ Population Status: Due to an extremely low reproductive rate, with only
two to fourteen pups born in alternate years, white shark populations are
regarded as vulnerable, with low numbers worldwide. Fewer than 100 whites may
live in California waters. Since the mid-1980s
scientists at the Farallones have gained valuable knowledge about the species'
hunting strategies, biology and behaviors.
„ Legal Protection: Recognizing white sharks' role in limiting seal and sea
lion populations, a coalition of sea urchin divers, surfers, scientists and
conservationists obtained legal protection of white sharks throughout
California waters. Hunting or fishing for them is prohibited, but they still
face threats from human disturbance. The sanctuary may consider legislation to
prevent the use of attractants by dive operators or other disturbances that
could have negative impacts on this important population.
„ Human attacks: Although white sharks attack humans, rarely fatally,
scientists believe they mistakenly confuse a swimmer's or surfer's silhouette
for that of the seals and sea lions the sharks prefer. There have been 106
shark attacks on humans in the last 50 or so years off California, 10 fatal, according to the
Department of Fish and Game.
„ Prey or Predator? The only animals known to hunt white sharks are killer
whales and humans. The sole documented attack on a white shark by a killer
whale occurred in the Gulf of the Farallones National Marine Sanctuary at the Farallon Islands in fall, 1997.
„ "Shark Bus:" To promote awareness of sharks and the conservation
issues which affect them, the Farallones marine sanctuary is offering a new
mobile public outreach program, the Shark Bus. For information, contact
Education Specialist Christy Walker at 650/ 712-8948 or at
Christy.walker@noaa.gov. For other sanctuary programs and issues, visit the
websites at
www.farallones.noaa.gov and www.farallones.org, or call 415/ 561-6625.
White Shark Bites
Scientific name: Carcharodon carcharias
Maximum length: 20+ feet (6 meters)
Maximum weight: approximately 7,000 pounds ( 2,613 kg)
Lifespan: Estimated 50 to 100 years, possibly longer
Distribution: Coastal and offshore waters, in surface waters and to depths
of 2,275 feet (700 meters).
Concentrations are found off South Africa, Southern
Australia and California.
Diet: Bony and cartilaginous fishes when young. On reaching 10-12 feet in
length they begin to prey on seals, sea lions, dolphins and porpoises, and to
scavenge dead whales.
Conservation Status: Unknown; but due to an extremely low reproductive rate
(only two to fourteen pups every other year), the species is regarded as
vulnerable, with low populations worldwide. Fewer than 100 whites may live in California waters. Although protected against
"take" under the California Code of Regulations/CDFG ¤28.06, because
of their wide-ranging habits they are vulnerable to hunting outside State
waters.
NOTE: White sharks are warm-blooded; their body temperature can reach
50-62.6 degrees F. above ambient sea temperatures.
Media contact: Mary Jane Schramm, 415/ 561-6622 ext. 205; <maryjane.schramm@noaa.gov>