Shark tank: Florida's mysterious shark migration
Nobody would confuse them with snowbird retirees fleeing frigid northern winters for Florida's sunny shores. But thousands of black tipped and spinner sharks head south from North Carolina each winter for similar reasons: warmth and fresh seafood. If your next Florida getaway coincides with their annual migration, come prepared to share the water with these amazing, and nearly always harmless, creatures.
Picky, picky, picky
Like Goldilocks testing the porridge, black tipped and spinner sharks avoid water that's too hot or too cold. Their "just right" water fluctuates between 69 and 75 degrees F, and they search for those temperatures between Palm Beach and Miami on Florida's coast. In most years, they find them between January and mid-April. When the waters climb above 75 degrees, the sharks turn around and head north.
To the sharks, migration means a dinner date with perks. They reach Florida in time to gorge on schools of smaller fish – mullet, herring, sardines and anchovies are particular favorites. They also mate. Females who mated the previous year leave the males for protected inlets, where they give birth to live babies.
Know before you go: The sharks' prize hunting spots are inlets where their prey enter and exit every day. Choice locations, according to Florida Atlantic University professor Stephen Kajiura, include:
- Jupiter Inlet at the northeastern corner of Palm Beach County
- Port Everglades Inlet, connecting the New River at Fort Lauderdale to the Atlantic
- Baker's Haulover Inlet, connecting the northern end of Biscayne Bay to the Atlantic
- Government Cut, the Port of Miami's harbor entrance
The migration zone
The migrating sharks stake out a corridor extending roughly 600 feet – or about two football fields – beyond the beach water line. Airborne researchers from Florida Atlantic have photographed more than 10,000 sharks spread out between Jupiter and Palm Beach on a single night, and those were just the ones in camera range. Given their tendency to remain within 100 feet of the ocean's surface and their ability to swim in just a few inches of water, the chances of encountering one may be much greater than you'd like to think.
Staying safe in the water
What are the odds of black tipped shark actually harming you? Fewer than 30 of more than 800 identified shark attacks in the world have been blamed on the 5- to 6-foot fish, with just one proving fatal. In Florida, you're 30 times more likely to be the victim of a lightning strike than of being attacked by any kind of shark.
To reduce your risk even more, follow some sensible precautions:
- Stick to clear water. In cloudy water – such as that found along Florida's northern coast – black tipped sharks may confuse paddling hands with the fish they're hunting.
- Stay clear of areas where people are fishing or birds diving. If anglers think fish are around, so do the sharks.
- Swim, snorkel or surf with a group; sharks tend to attack single targets.
- Avoid swimwear with bold, bright patterns and remove jewelry before going into the water. Shiny or high-contrast objects may attract sharks.
- Always swim within sight of a lifeguard.
- Stay out of the water during and after twilight, when sharks are most active.
- Don't swim with an open, bleeding wound.