Now, marine scientists have shown for the first time that juvenile great white sharks select warm and shallow waters to aggregate within one kilometer from the shore. These results, published in Frontiers in Marine Science, are important for conservation of great white sharks—especially as ocean temperatures increase due to climate change—and for protecting the public from negative shark encounters. Baby great white sharks ("pups") don't receive any maternal care after birth. In the studied population off Padaro Beach near Santa Barbara in central California, pups and juveniles gather in "nurseries," unaccompanied by adults. "This is one of the largest and most detailed studies of its kind. Because around Padaro Beach, large numbers of juveniles share near-shore habitats, we could learn how environmental conditions influence their movements," said senior author Dr. Christopher Lowe, a professor at California State University. "You rarely see great white sharks exhibiting this kind of nursery behavior in other locations." In 2020 and 2021, Lowe and his team used darts to tag a total of 22 juveniles with sensor-transmitters. These were females and males aged between one and six years old. Great white sharks can live for up to 40 to 70 years. The sensor-transmitters measured local water pressure and temperature in real time, and tracked each juvenile's position by sending acoustic "pings" into an array of receivers, spread out over approximately 5.5 sq km along the shoreline. These methods had been approved by the university's Animal Care and Use Committee and California's Department of Fish and Wildlife. Tracking was halted during the winter months, when juveniles temporarily left for offshore waters. The researchers gathered further data on the temperature distribution throughout the local water column with an autonomous underwater vehicle. They then used artificial intelligence to train a 3D model of the... |