Fewer people at seaside vacation resorts could lower attack numbers, as could cold or rainy weather patterns that kept swimmers out of the water.
Another factor may be the continuing decline of many shark species due to overfishinga major problem that illustrates the human threat to sharks is much greater than vice versa.
While shark attack numbers are relatively small, humans kill perhaps 20 to 100 million sharks each year by fishing activities, according to data from the ISAF. Because of such over fishing, loss of habitat, and other man-made intrusions some shark populations have dropped dramatically, by some 30 to 50 percent.
"Unfortunately, we see shark attacks a lot on televisionbut shark attack is a minor league problem," Burgess told National Geographic News. "The real problem, with regard to sharks, is they are being over fished and also losing their habitat around the world. Many populations are declining at an alarming rate."
Still, Burgess cautions that while declining shark populations greatly threaten the ocean ecosystem they are not necessarily responsible for a decrease in attacks.
"Shark attacks are a function of the number of humans in the water, and of the number of sharks in the water," he explained. "There may be reduced shark populations. But human populations grow so fast, and so many more people are in the water each year, that it probably makes up for the loss of sharks. So human/shark interactions will likely rise as number of humans in the water rises each year."
"Similarly, if we're able to turn the tide with fish management procedures and bring numbers of sharks back up, the fact is that those numbers would still be so small relative to the number of humans that more sharks doesn't mean we'll see a big increase in the number of attacks."
Summer Season Means Shark Worries
As long as any attacks occur, they are sure to create some anxiety on beaches this summer.
"Sharks are fascinating creatures and one of the few animals that can attack, kill, and sometimes consume a human," Burgess said. "That will always make them a draw. We hope that through reasonable efforts at education we can portray them in the manner that they deserve and keep things like shark attack in perspective."
"Memorial Day weekend is the first major holiday weekend of the year for people entering the ocean, and it's almost inevitable that we're going to have a few nips," said Burgess in a statement released prior to the holiday.
"We need to understand that there are millions of people spending a lot of time in the water doing the kinds of things that are provocative to sharkskicking, splashing, and screamingin an area that many species of sharks call home," he said.
The possibility of an attack is real, and swimmers can take precautions such as avoiding dark or dusk hours, swimming in groups, and not going into the water with open wounds.
Still, the chances of even a minor shark attack remain quite remote. In the United States, for example, ISAF calculates that the annual risk of death from lightning is some 30 times greater than that from shark attacks. At the beach itself, incidents such as drowning and cardiac arrest are statistically much more dangerous than sharksas is the hectic Memorial Day traffic you'll likely encounter on the way to any seaside retreat.
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