PALM BEACH, Florida Several beaches in South Florida have reopened to the public after thousands of sharks were spotted swimming close to the shoreline.
For the last two days, three beaches in Palm Beach County were declared off-limits to swimmers after the shark migration.
The beaches reopened Thursday, though unseasonably chilly temperatures likely will keep most swimmers away anyway.
When sharks are spotted near shore, lifeguards close beaches for at least a half-hour.
CBS 4 Miami reported the marine predators, mostly blacktip and spinner sharks, had been spotted from Boca Raton to Jupiter since the start of the month.
Shark sightings off South Florida are not uncommon this time of year.
Once a shark appears near the shore, a lifeguard will close the beach and keep it closed until half hour after the last shark is spotted.
If you're swimming at a South Florida beach, be sure to swim along beaches where lifeguards are present. Also, leave your jewelry on the shore. Scientists say sharks are attracted to silver, along with the colors yellow and gold.
Shark expert George H. Burgess cautions that recent overcast skies may have made it more difficult to spot the sharks in some areas, according to The Palm Beach Post.
''The sharks are in the water all the time,'' Burgess said. ''You don't see them, but they're there.''
Intermittent closures are still possible.