Adam Brown, White Shark Biologist with Point Reyes Bird Observatory, has been studying white sharks on Southeast Farallon Island since 2000. He will be Beth and Mike's guest on Coastal Currents on Feb. 8 at noon on KHUM, 104.3 and 104.7 FM.
White sharks (Carcharodon carcharias) are the ocean's largest predatory sharks. The occasional encounter with humans (and movie producers) has made them the most famous. Although they can grow to almost 21 feet (7 meters), the length of an average shark is closer to 15 feet (5 meters); they weigh about 1,500 pounds (700 kg). White sharks, like some other fish such as salmon sharks and tuna, are warm-bodied -- that is, parts of their bodies can be warmer than the cold water in which they swim.
In the eastern Pacific, white sharks can be found from Alaska to Mexico, but you don't often see them north of Washington State. They hang out near haul-out sites for marine mammals, their main food. People used to believe they roamed only along the California coast. But our tags show that they travel regularly from California to Hawaii. Juvenile white sharks are found in the Southern California Bight, which appears to be an important nursery ground.
The World Conservation Union lists white sharks as vulnerable. Concerns for white shark populations have led to their protection in Californian and Mexican waters. To ensure their long-term survival, we need much more information about where they go to feed and breed. The recent tagging results indicate how little is actually known about white sharks. Also, white sharks will also provide a valuable comparison to results from salmon and mako sharks that are also capable of elevating their body temperature.
To view the white shark tagging map by Tagging of Pacific Predators (TOPP), click HERE.
Tagging of Pacific Predators (TOPP) began in 2000 as one of 17 projects of the Census of Marine Life, an ambitious 10-year, 80-nation endeavor to assess and explain the diversity and abundance of life in the oceans, and where that life has lived, is living, and will live.
