MONTEREY, Calif. - There is a dramatic increase in the number of great white sharks swimming in Monterey Bay, including an area off Santa Cruz County where a surfer was killed last year, according to a new study published Tuesday.The study found younger great white sharks that are between 5 and 9 feet long and traditionally concentrated in warm waters off northern Mexico and Southern California have moved north since 2014 as water temperatures have warmed, the Mercury News reported.Where once there were no juvenile white sharks spotted in the ocean between Aptos and Capitola, now there are dozens seen every year, according to research from scientists at the Monterey Bay Aquarium, Duke University and California State University Long Beach..