Parents know that Pacific Palisades is a great place to raise kids, yet who among us knew that the waters off Will Rogers State Beach are also hospitable to juvenile great white sharks? According to experts from the Monterey Bay Aquarium and the Marine Conservation Science Institute (Marine CSI), the area offshore is a playground for young great whites who are mostly under 10 feet in length and non-threatening to local swimmers and surfers. ’This is a nursery ground,’ said John O’Sullivan, Curator of Field Operations for Monterey Bay Aquarium. ‘In August, we saw seen five 4- to 7-ft. sharks within 200 yards of the beach. Lifeguards have told us if they had to close the beach every time they saw a shark, they’d be closed every day. The sharks are there whether people like it or not.’ The 5-foot female shark in the adjacent photo was captured off Will Rogers in August and is currently on exhibit in the million-gallon Outer Bay Exhibit at the Monterey Bay Aquarium. She’s the fifth one to go on display since 2002. Before she was transported north, she was kept in a large ocean pen off Paradise Cove in Malibu and observed to see if she would feed, which she did. ‘She’s doing the best of any previous sharks,’ said O’Sullivan, noting that the previous great white wouldn’t eat, possibly because it was stressed, and was released back into the ocean after 11 days. Additional ‘Palisades’ great white sharks were filmed in September by Fisher Productions, when the Marine CSI came to this area to tag adolescents. ’We were looking for 10-ft. sharks, but we didn’t tag any,’ said marine biologist Nicole Nasby-Lucas, whose boat was located off Gladstone’s and The Chart House restaurants. ‘We know that juveniles are found along the Southern California coast and that adults are found at aggregation sites off the Farallon Islands near San Francisco and Guadalupe Island off the coast of Baja California, so we’re trying to fill in the gap between these two life-stages.’ O’Sullivan and Nasby-Lucas say that surprisingly little is known about the great white population size, where pups are born, where the juveniles come from or migrate to, and where adolescents are found. Researchers are trying to answer those questions about a species that is protected in California waters and is listed as threatened in the Pacific. Research is not easy because of the difficulty of capturing and handling great whites, as well as their vast habitat. One theory is that the great white females, which can reach 22 feet in length, give birth, or pup, in June somewhere between Point Conception and central Baja, but there is no data to support that speculation. ’In all of our history of research, we have never caught a near-term female in the Eastern Pacific,’ O’Sullivan said. He explained that sharks, which are at the top of the food chain, with no known predators other than man, have internal fertilization and give live birth to a litter of four to 12 pups. Once the juveniles, who can be up to five feet in length, are released in the ocean there is no maternal care. The pups live off small schooling fish, grunions and sardines, until they are large enough to begin consuming the likes of elephant fur seals, sea lions and whale carcasses.”””””’ ’After age seven, the shark can move to colder water,’ said O’Sullivan, who noted that it is challenging to estimate the age of the shark by its length, because they have individual differences, much like humans do. ’Researchers are studying the older and younger sharks,’ O’Sullivan said. ‘But no one knows about the adolescents.’ Tagging, tracking, photographing and aerial surveillance are all tools that scientists use to answer questions about great whites. ‘We still do not have a clear understanding of the population,’ O’Sullivan said. ‘Historically they disappear in September, returning in June.’ Tagged adult sharks have been known to travel to Hawaii, and have been seen swimming and congregating in an area in the central Pacific dubbed ‘SOFA’ (Shared Offshore Foraging Area). ‘One theory is that there’s a food source that draws them there,’ said Nasby-Lucas of the Marine CSI. She said the boat spotted off shore in September belonged to Fischer Productions, which was filming Institute scientists as they tagged sharks. To do the tagging, a spotter plane first identifies a shark, the boat approaches and a baited hook is placed in the water, and then the shark is caught and brought on board. A Smart Positioning Transmitting Tag is attached to the dorsal fin, which will provide real-time tracking data every time the shark’s dorsal fin comes out of the water and a satellite is overhead. ’We have our theories about sharks,’ Nasby-Lucas said, ‘but we’re still trying to answer the questions.’ The National Geographic Channel will air ‘Expedition Great White,’ produced by Fisher Productions, on November 16 at 9 p.m. The program will feature tagging of great white sharks off Guadalupe Island by Marine CSI. For blogs about the juvenile great white on display at the Monterey Bay Aquarium, visit:www.montereybayaquarium.org.
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