(NEW YORK) -- As you head to the beach this week along with hoards of other Americans, you have more to be cautious of than the heat. There have been shark sightings on both coasts, leading to panic in some areas.
Just like a scene out of the movie Jaws, California beach-goers spotted a 14-foot Great White shark off the coast of San Diego on Monday, prompting the immediate closure of the beach. The La Jolla Shores beach re-opened in time for the Fourth of July holiday after there was no sign of the shark overnight.
Area lifeguards told ABC News that while shark sightings are fairly common there, they should be taken seriously.
Another shark was caught just north of La Jolla Shores the same day. A fisherman reeled in what is believed to be a shortfin mako shark 15 miles off the coast of Marina Del Rey.
“It’s been at least a couple of years since I’ve seen anything that big,” Tony Velardez, an assistant manager at Del Rey Landing, told ABC News' Los Angeles affiliate KTLA.
The fisherman said he believed the shark was around 800 pounds -- their scales only go up to 750.
Meanwhile, the next day, all the way on the other side of the country, fishermen in Massachusetts spotted two more Great Whites off Cape Cod.
And this wasn’t the first sighting in that area -- a 12- to 15-foot shark was seen over the weekend in Chatham, the state’s first of the season.
Authorities issued an advisory telling beach-goers to stay away from seals -- one of sharks’ favorite snacks.
Back over on the West Coast, Lt. Andy Lerum reiterated the advice from Cape Cod authorities.
“Humans are not normal prey for sharks and so every time there is an attack it’s assumed it’s a mistaken identity, so it’s better not to look like a seal if you can avoid it,” Lerum told ABC News' San Diego affiliate 10News.
So enjoy the beach weather, but stay alert if you’re planning to cool off in the water this week.
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