The great hammerhead shark is a magnificent animal. It's also one of 24 shark species illegal to harvest in Florida waters, up to 9 miles off the coast.
Sadly, four of them washed up on Sarasota beaches in late June and July, according to the Bradenton Herald.
What happened to them? Most likely, they were caught and released, but didn't survive the trauma of the fight and handling.
"This particular species of hammerhead is just so fragile that they go into physiological stress," said Robert Hueter, director of shark research at Mote Marine Laboratory.
One of those stressors during this time of year is the temperature.
Whether shark, catfish, or bass, a fish's metabolism speeds up in warm water because it is cold-blooded. That means it burns more energy and, as a consequence, must consume more food to fuel sustain itself. It also means that its oxygen needs are intensified. But . . .
"The hotter the water is, the less oxygen it can hold," Hueter said.
Now factor in the energy and oxygen expended in a struggle to escape once hooked, and fish die, especially larger fish, which simply cannot recover no matter how carefully they are handled once they are brought to the shore or boat. In essence, they die of exhaustion, unable to gain the oxygen they need to recover.
That's why delayed mortality increases for bass tournaments during summer. And that's why those great hammerheads did not survive.
Hueter added that hammerheads likely are especially vulnerable because their mouths are so small in comparison to their bodies.
“As soon as it’s obvious that it is a hammerhead, the better thing to do would be just to cut the line or cut the leader, get as close as you can to the animal without spending a lot of time pulling it in,” he said. “Cut it and let it go.”
Dragging a shark, or any other large fish, such as a Goliath grouper, onto shore always is stressful for the animal, but especially so during summer. Meanwhile, inshore and beach fishing for sharks is more popular than ever.
"We're seeing more (sharks) than we've seen before washing up on beaches," Hueter said.
The fish is much more likely to survive if kept in shallow water for dehooking and photos.
In addition to hammerheads, bull and black tip sharks also are especially vulnerable to stress. At the other extreme, nurse and lemon sharks are among the hardiest.
Here are some handling tips to help ensure survival. They apply specifically to sharks, but are good tips for handling big fish of many species when caught on bait.
- Use heavy tackle and non-stainless circle hooks
- Use a dehooker
- Cut the leader or line quickly, leaving as little as possible attached to the hook
- Do not bring sharks out of water
- Leave shark in enough water so that it can breathe through its mouth and gills
- Shoot photos in process of releasing