http://www.digitaljournal.com/news/environment/great-white-sharks-making-a-splashy-comeback-off-usa-coasts/article/387636

Great white sharks making a splashy comeback off U.S. coasts

Posted Jun 25, 2014 by Megan Hamilton
A New Jersey man fishing with friends off the coast of Cape May has startling evidence that great white sharks are making a comeback after one of the huge fish bit the outboard motor on his boat.
Photos of Great White Sharks taken by Daniel Botelho
Photos of Great White Sharks taken by Daniel Botelho
Dive Photo Guide/Daniel Botelho
Fisherman Steve Clark, owner of the 35-foot boat, was shocked at the size of the 16-foot shark, which he estimated to weigh a ton, the Inquistr reports.
"Obviously, I was a little bit stunned. I didn't say anything to anybody, I was looking at it, trying to process the information, 'cause it was quite a big fish," he said.
The great white continued to circle the boat for 20 minutes, sometimes poking its' head out of the water to look at him, he said. In one nerve-wracking moment the shark grabbed a basket that was loaded with bait bags of chum. The men had intended to use the bait to attract mako sharks, but the wily fish made off with the prize. The men were left with an awesome video.
Clark and his friends work with the National Oceanic and Atmospheric Administration (NOAA), as part of the Apex Predator Program, and as such, they work to tag sharks, Inquistr reports. It's likely that the men didn't have much to worry about, as shark attacks on humans are rare. Only 106 unprovoked white shark attacks have been reported in U.S. waters since 1916.
Two recent studies show that the numbers of these magnificent sharks are on the rise on the Pacific and Atlantic coasts of the U.S.
Scientists had feared that great white sharks were in decline, but the research from the studies suggests that conservation efforts have given the creatures a boost, Mashable reports.
"It's a good news story and one we don't hear often enough with sharks," said researcher George Burgess, of the Florida Museum of Natural History at the University of Florida in Gainesville.
Great white sharks are rather mysterious creatures, and relatively little is known about them. Therefore, it's challenging for scientists to assess how large their populations are, Mashable reports.
Being solitary creatures, these sharks spread out widely in the vastness of the ocean. As a rule, large numbers of great whites don't aggregate around established feeding areas, especially along the east coast. Adults can reach lengths of 20 feet (six meters), making them difficult to capture. Also, unlike whales and other marine mammals, sharks don't need to breach the surface to breathe.
"They're rare animals," said Tobey Curtis, a shark researcher at the NOAA's Greater Atlantic Regional Fishers Office in Gloucester, Massachusetts. "They're not commonly seen, and it takes a lot of effort to track down verified records of sightings and fishery captures."
Curtis led a study on great whites off the east coast, which was published this month in the journal PLOS ONE, Mashable reports.
Rising numbers in the east
Curtis and his colleagues pored over 649 confirmed records of western Atlantic great white sharks spanning the years 1800 through 2010, using sources as varied as commercial catch data, fishing tournament results and even newspaper articles. The records make up the largest dataset of great white sharks ever collected for the region, the group noted.
While the team didn't have enough information to make an estimate of the real numbers for the area's shark population, they were able to establish a trend. What they found suggests that populations of great white sharks took a nosedive in the 1970s and 1980s due to the expansion of recreational and commercial shark fishing, Mashable reports. With the advent of conservation and management efforts in the 1990s, sightings of the big fish began to rise once again.
Interestingly, the study also found patterns that show where great whites tend to move throughout the seasons. Like humans, they preferred Florida waters in the winter and moved further north in springtime — sometimes even winding up as far north as Newfoundland and the Gulf of St. Lawrence in Canada.
Rising numbers in California
Burgess was also involved in Curtis' study and led a separate investigation that was also published this month in PLOS ONE, Mashable reports. In this case, the investigation estimated great white shark populations off the coast of California. In a departure from their east coast counterparts, west coast great whites do gather around feeding hot spots where seals and sea lions congregate.
Earlier reports about the demise of great whites have been overstated, Burgess said. The data he collected suggested that populations in California are rising, with perhaps some 2,000 sharks. An earlier study from researchers at Stanford University suggested that only 219 great whites lived in the region.
Nevertheless, researchers remain cautious about declaring victory. Sharks, along with stingrays and skates, are elasmobranchs, and each share biological traits that make it difficult for their populations to recover from steep declines. They grow slowly and reach maturity at a late age. Unlike many other fish, females are fertilized internally and only have a few offspring at a time, according to Mashable.
Since there is a lack of historical data, this makes it difficult for scientists to establish a baseline that they can use to measure their conservation success.
"They're back on the way up, but to be honest, I don't think any of us know what 'up' is," Burgess said, according to Mashable. "The fact is, we have no real idea what [the population] was before we started screwing around with the environment on both coasts."
Sharks are definitely survivors and they have a long history that stretches out well before the time of the dinosaurs, the Smithsonian reports. They have, in fact, been here for at least 400 million years. However, like so many other species, they are impacted greatly by our actions. Sharks are frequently killed by fishermen's longlines and trawlers; they are poached illegally for shark fin soup and hunted illegally for sportsfishing so that their jaws can be used as trophies. Sharks are also killed by nets that are placed along coastlines to keep them away from beaches, and pollution also takes a toll because toxins and heavy metals can build up in a shark's body.
The fact that populations of great white sharks are increasing on the Pacific and Atlantic coastlines of the U.S. gives scientists the hope that despite all of this, these most remarkable creatures will survive.