Sharks and rays, which are members of the elasmobranches species, have long exerted a fascination as some of the planet’s fiercest predators.
Now Scripps Institution of Oceanography has launched a new organization to study sharks. Its goal is to bring together scientists, policy managers and the public to help increase knowledge and awareness, and coordinate resources for a better understanding of sharks that are native to Southern California coastal waters.
The consortium also hopes to elevate public awareness for protecting and conserving the shark.
The group was unveiled July 31 during a public lecture on the region’s sharks by Dr. Jeffrey Graham and graduate students Dan Cartamil and Nick Wegner at Birch Aquarium.
Graham is a research physiologist and marine biologist at Scripps Institution of Oceanography and a principal player in the new team.
Recently, members of Graham’s laboratory tagged adult thresher sharks so that they could track and communicate with the animals.
“The past century has seen marked reductions in shark populations in the Southern California Bight due to the impacts of commercial and recreational fisheries and changes to critical shark nursery habitats,” Graham said. “There is a great need for information to properly manage shark and ray resources, which are vital to the economic and ecological health of the region.”
The Southern California region extends 450 miles along the Pacific Ocean coast, from Point Conception north of Santa Barbara southward to Cabo Colonet in Baja California, Mexico.
Graham said he has been putting this effort together over the past four to five years. The consortium is based at his lab at Scripps.
“I have been looking more closely at some of the ecological, biological and natural history questions about sharks and rays that can be answered through research in my laboratory,” he said. “To do this, members of my laboratory are using shark tagging through satellite and acoustic devices to help us understand shark activities and their habitats.”
As a main visionary for the project, Graham also becomes a facilitator for linking shark-related resources in the region. His goal is also to educate and involve the public in issues vital for shark and ray conservation.
“Outreach activities will be conducted through the Birch Aquarium at Scripps,” Graham said. “Also, we seek sponsors and scientific grants that have educational funding set aside so that we can organize shark symposia for teachers, who can in turn teach their students. Every kid, it seems, has a fundamental interest in sharks, and it is possible to imagine ways to teach about sharks that can also stimulate kids to apply skills in mathematics and critical thinking.”
Currently, at least 40 species in the shark/ray group exist off the coast of Southern California, Graham said. Some migrate here while others make the Southern California “Bight” their permanent home.
An additional goal of the group is to raise the level or awareness for sharks and rays through research and outreach activities, he said.Cartamil added that under routine conditions in Southern California, fisheries managers, scientists and public officials rarely have worked together.
Now, this group will add to increased knowledge sharing, understanding and communication for a common goal.
The consortium will also work closely with Mexican representatives that include Mexican fisheries, so that the U.S./Mexico perspective will include the Southern California Bight ecosystem.
Both Graham and Cartamil say this effort is crucial, because commercial and recreational fisheries are catching sharks at greater rates than ever before.
“Recreational fisheries used to be small in number off the San Diego coast in the summer,” Cartamil said. “Now, we see hordes of boats taking thresher, mako and blue sharks. We don’t know what the impact of that is on the overall population.”
Although thresher is typically offered at many fish markets, most sharks have little appeal as a commercial human food.
“Rather, sharks are trophies, signifying the coming of age or a mastery of the environment,” Graham said. “Fishing for this purpose at the expense of sharks is problematic for me in this time of decreasing numbers, and harkens back to a time when food gathering by hunters was really essential for survival.”
In the case of sharks that have appeal as a food supply or for some other use, history shows that no shark fishery has proved sustainable. It must be carefully regulated, and this requires base information of the kind our consortium will help acquire.
Those familiar with Southern California coastal waters are aware of the potential for danger.
“Most residents of La Jolla know about the potential for a great white shark attack,” Graham said. “There was one in 1959 and another incident involving a kayaker about five years ago. Both of these are controversial and may or may not have occurred. It is frequently debated.”
Then there are the harbor seals that make the Children’s Pool at La Jolla Cove their home.
“This is controversial, to say the least, and one aspect of the presence of harbor seals is the possibility that great white sharks will come in there to feed on seals and mistakenly eat a swimmer or surfer,” Graham said. “That would be a tragic event.”
To help increase public access, a Web site is being developed that will present catch rate data for both the academic and public realms.
Other areas will be studied, including juvenile shark activity and the locations of nursery grounds that are vital to the health of shark populations, Graham said.
“Each summer, there is a large presence of leopard sharks in the waters inside of La Jolla Bay, near the area of the rock slide and the Marine Room,” he said. “These sharks are harmless and can be seen by kayakers who often snorkel with them in shallow water. Why these sharks aggregate there is really unknown, and the kind of thing that, with sponsors and grants, a Scripps graduate student may be able to study.”
A related problem faced by all beachgoers is the potential for stingray stings.
“These occur often and seem to be more frequent at certain times,” Graham added. “Data on stingray abundances is another subject that is ripe for study.”
For several years, Graham’s laboratory has focused on sharks both in the physiological and biological perspectives. Studies started expanding when shark populations began shrinking.
The group’s association with TimeWarner Cable and the Discovery Channel is based on an annual dedication to the Birch Aquarium at Scripps.
“We offer a range of shark-related activities and events,” Graham said. “For now, the major question for shark biologists is defining the nursery grounds for sharks and determining to what extent sharks migrate from one habitat to another to have their offspring.”
Defining these areas and identifying them as nursery grounds could then make it possible to work with some of the commercial and recreational fishers to better protect those areas.
“This would give the younger sharks a chance to grow up and be part of the next generation,” Graham said.
For further information, visit www.aquarium.ucsd.edu. For information from the data tracking efforts about shark habitat and populations, go to http://explorations.ucsd.edu/shark.