(CNN) — Jeffrey Heim woke up on May 30, 2021, with one thing on his mind: Sharks.
Specifically, shark teeth. They're his passion and his business. An unsuccessful attempt the day before to find any of them only fueled his obsession to find some on his next outing, he told CNN Travel recently.
So on a hot, sunny Sunday in Sarasota County, Florida, the 25-year-old Heim proceeded to the Myakka River on a spot about 45 minutes from the Gulf of Mexico.
He had been there numerous times and was comfortable with plunging into its murky waters to find the teeth of extinct megalodons in the riverbed.
He put on his wetsuit, mask, fins and snorkel and entered the water from the shore, not far from a restaurant along the riverbank.
Heim slipped beneath the surface. He was under no more than one minute when he felt something. Something bad.
"I didn't hear anything, didn't see anything. I just felt like a blunt force object -- like someone ... swinging a baseball bat and just whacking my head. But mostly what I felt was what I thought was a huge boat just slamming into me and just pulling me down."
To his shock, it wasn't a boat.
He was in the water, alone and face-to-face with an alligator.
Gator attacks: Rare but fascinating
Alligators sun themselves in Florida City, Miami-Dade County. Every county in Florida has gators.
Luca Nichetti/EyeEm/Getty Images
Heim was in a situation many people probably fear but very few actually experience: an attack by an alligator.
An estimated 5 million wild American alligators are spread out across 10 states in Southeast and beyond, including parts of North Carolina and even the extreme southeastern tip of Oklahoma.
Louisiana has an estimated 2 million wild gators in a state of about 4.65 million people. Florida sports roughly 1.25 million alligators (and more than 1,000 American crocodiles). Georgia has about a quarter of a million.
Some of these gators inhabit places where lots of people live and many others vacation, such as lakes and rivers all across Florida and coastal South Carolina.
Yet gator attacks aren't that frequent and deaths even more infrequent (deadly attacks from dogs and horses and other mammals are more common). It turns out gators, in natural conditions, simply aren't that interested in people, according to Kimberly Andrews, a gator and snake expert with a doctorate in ecology from University of Georgia's Marine Extension and Georgia Sea Grant and who manages its Coastal Ecology Lab.
"We are not their prey. If you think about it, we're quite dangerous to attack. We've got arms and legs. We can stand upright. We can walk, we can swim. ... We're not a good animal to pick a fight with."
"Unless they're confronted, they're going to stay on their own turf."
Nonetheless, people continue to be fascinated by such possible encounters.
Gators and people co-mingle, particulary around Southeastern golf courses like these little ones at the April RBC Heritage tournament on Hilton Head Island, South Carolina. Experts say just leave them alone, and they'll leave you alone.
Stephen B. Morton/AP
Andrews wants to dispel the notion of gators as aggressive, ravenous menaces on the move. "They're called ambush predators. We also call these 'sit-and-wait' predators," she said.
They're large, so it's "energetically costly for them to be really active. ... We would be considered an active forager. We go out and find our food." Not so with gators.
"When you come down to it, they're not that maneuverable. Large body. Small legs. And this also plays into why the perception of their danger is exaggerated from the actuality."
Nonetheless, caution is advised when you're in gator territory, be that at golf courses, swamps, lakes, rivers and hiking and bike trails and fishing spots along waterways.
Best defense: Avoid an attack
Fragrant water lilies are common in Okefenokee Swamp National Wildlife Refuge in southeast Georgia. Always be alert in areas where vegetation might obscure alligators.
Education is key to avoiding a bad encounter, Andrews said. Start with knowing when gators are most active.
Courtship season starts as spring warms up; mating extends in early summer; and in Okefenokee Swamp in southeastern Georgia, "we start to see eggs hatch out starting in September and October. ... And that's when the females are most protective when they feel someone is threatening their babies," Andrews said.
Your best season is winter: If it's cold, "they're not doing whole lot."
When temperatures start settling into the 80s (27 Celsius), gators become mostly nocturnal. So it's best to avoid that refreshing night dip in unknown waters when it's hot.
Don't provoke, don't feed, don't panic
A man paddles in the Florida Everglades. If you spot a gator while on the water, respect its space.
jimfeng/iStock Unreleased/Getty Images
Unprovoked attacks are rare, Andrews said. People are usually the provocateurs, not the gators. Gators can be disturbed or confused when folks have been known to try to grab them by their tails or go in for close-up photos of sunning gators
Even worse, people will feed them. Then the reptiles start to associate humans with food. That's when gators can be most dangerous -- when they've lost their natural fear or disinterest in people.
"They're more likely to take the easy way out and get our food than to do the work to fight for it," Andrews said. "In areas where we have high rates of tourism but not a lot of education and oversight of how people are interacting with alligators, we see feeding issues."
If you do have a gator encounter, she suggests staying calm and respecting its territory
A kayaker navigating the Waccamaw River in North Carolina had a close call with a nearby alligator.
"Say you're kayaking, and you see an alligator, just keep going past it. Give it a wide berth, as much as the space will allow," Andrews said.
"Don't take the paddles and slap the water. Sometimes people do that to scare the alligator off," but you're actually indicating you're a direct threat.
"If for some reason they start to swim toward you ... usually try to go in the other direction and just show you're not interested. Or paddle right on by and ignore the animal."
Also, never mess with the reptiles' children.
"We always tell people that those one-foot baby alligators, even though they're so cute, they're the most dangerous sized alligator to mess with." That's because there's possibly a nearby mother ready to protect her young.
More ways to avoid an attack
An alligator crosses a road on Merritt Island at sunset near the Kennedy Space Center in Florida. Watch out for alligators crossing roadways, especially at dusk during mating season.
Gregg Newton/AFP/Getty Images
• Don't feed ducks, turtles or other animals that share waters with alligators.
• Stay about 60 feet (18 meters) or more away from an adult alligator. If an alligator hisses or lunges at you, you are too close.
• If you're driving, let an alligator cross the road. They move across roadways the most often in spring and summer.
• Supervise pets and children when you're in gator territory. "Large alligators do not recognize the difference between domestic pets and wild food sources," the SREL says.
• Avoid heavy vegetation in and near the water's edge.
Two enormous alligators were spotted in the city of Venice, Florida taking a stroll through residential neighborhoods.
• Never swim outside of posted areas, and swim only during daylight hours. Alligators are most active between dusk and dawn.
• Get rid of fish scraps in garbage cans at boat ramps and fish camps; don't toss them in the water.
Experts also advise people to call local or state authorities if you see alligators roaming around neighbors and other places you wouldn't expect. Do not try to handle the reptiles yourself.
As for Jeffrey Heim, these tips were more than theory.
A diver searching for prehistoric shark teeth in Florida's Myakka River is recovering after an alligator bit him on the back of his head. WFTS' Ryan Smith reports
Heim was in serious trouble, and he knew it.
The gator had already bit him in the skull and on the hand. And it was coming toward him again.
The gator "pulled my mask off and pulled my head down towards my stomach. And then I come up, head above water. I no longer have the mask with the GoPro that's filming. And we're both looking at each other, and we both sit there for about two or three seconds, and I feel my head."
He wasn't sure what he was feeling at the time, but he learned later it was his scalp, partially torn off his skull and flapping in the water.
Then "she lunges at me and I back away calmly ... like I would with my experience with sharks, you don't want to act like prey. So I just backed away to keep my space."
"And then she really aggressively lunged at me ..."
What to do if you're attacked
Would you know how to defend yourself if an alligator started coming for you in the water?
Harry Collins/Adobe Stock
Heaven forbid you're that person like Heim who is being attacked by an alligator. Would you know what to do?
If the gator is trying to drag you under the water, "you have to assume at this point you're fighting for your life, and you've got to give it all you've got," Andrews said.
"We recommend trying to poke them in the eye, hitting them in the top part of the skull or the side of the jaw. Those points are sensitive on alligators just like they are on us," she said.
In a water attack, the danger is more from drowning than the bite, Andrews said. So get to land if possible. "We're better on land than they are. They're better in the water."
But don't assume all is safe if you're on land. And the alligator has more in its arsenal that a fearsome set of teeth.
You can be injured if you're hit by the tail. Gators can also whip around with their skull and use it like a battering ram. Andrews knows first-hand how dangerous that can be.
She was part of a capture team once that had a gator taped up and its mouth secured when it unexpectedly whipped its head around.
"It actually hit me broad with the side of its head across my shins ... and I blacked out. And I wondered, 'Oh my gosh, did I fracture my shin bone?' I had a lump the size of a tennis ball. It is amazing how muscular and powerful they are," Andrews recalled.
The gator uses its mouth. Use yours.
"Scream, make as much noise [as you can], not only fight back but make yourself as big and as much a pain in the rear end as you possibly can."
If people are nearby, they should call 911 for help, Andrews said. If a pole is nearby, someone can beat on the gator and give it another target.
"Another person in an attempt to rescue you should never come in the water after you and the alligator. They can help you most by being on the ground and helping you get to the ground," Andrews said.
Other ways to fend off an attack
An alligator moves through the waters of the Wakodahatchee Wetlands in Delray Beach, Florida. If you're ever attacked, try to get out of the water and on land.
Bruce Bennett/Getty Images
Here are some more survival tips from various wildlife departments and other experts:
• If you can escape on land, run away in a straight line. Experts debunk the advice to zig-zag. Gators can move really fast on land, but only in short bursts and distances before they tire out.
• Try to cause a gag reflex by jamming any objects you can reach into the back of the alligator's mouth.
• Sometimes a gator will reposition its prey in its mouth. With its jaw back open, that is your chance to escape.
• "Alligators clamp down with powerful jaws, then twist and roll. If an alligator bites your arm, it may help to grab the alligator and roll with it to reduce tearing of the arm," according to advice from the South Carolina Department of Natural Resources.
This is an American crocodile (Crocodylus acutus). Note the more slender V-shaped snout versus the broader, U-shaped snouts of gators. They are found only in coastal areas of southern Florida.
Arterra/Universal Images Group/Getty Images
All of this is specific to American alligators, Andrews emphasizes.
Other crocodilian species in places such as Africa and Australia can be more aggressive. We're actually prey-sized for some of these, she said.
But the relatively few crocodiles in southern Florida aren't known for attacking people.
This photo shows Jeffrey Heim recuperating after his attack and the extent of the injuries to his head.
One of Andrews' survival tips came in very hand handy as the female gator lunged yet again at Heim.
"I really backed away. Got out of that river as quickly as I could. I climbed out of the six-foot bank and stumbled over to the parking lot."
He was about to pass out, but he was able "to yell over to some people over at that restaurant."
Fortunately, they heard his cries for help and were able to assist him with a first aid kit from the restaurant and call 911.
While waiting for the paramedics, he wasn't in pain. But "the whole time I'm sitting down just super loopy and exhausted. That's when I thought I was going to die."
He ended up in the ICU in a hospital for two days but was back at work the next week "with staples in my head."
A happy co-existence: Blue skies are reflected in the still waters of the Everglades while tourists take airboat rides to visit alligators in the wild.
Alan Hill/Adobe Stock
Heim has now had time to reflect on what he did that day and on what others can learn from his attack.
"I knew there were gators there. This day, I basically did everything wrong," he said. "I was aware it was gator mating season, but I went to the river with too much confidence, especially being alone, and free diving, which I had never done in that river before."
"That cockiness, or confidence, led to the bite, honestly, even though this was an uncharacteristically aggressive alligator apparently. It was still the wrong time of year to go."
Like other young people who have spent time in the watery wilds in the Southeast, he was lulled into a false sense of security because he had been around gators before with no ill results.
"I was casually looking around for gators, but if I had even seen one, I had dove with them before and it hadn't caused an issue."
"I think the difference was this was near a restaurant, and fed gators are the most aggressive gators. So that's what the gator professionals believe contributed to this attack, too," Heim said.
"If you're going to dive in a river like that, which I don't suggest anymore, don't free dive. You're going to go up and down like their prey. And you're going to look much smaller that you actually are."
"Weigh all risks. Anything can happen at anytime to anyone. None of us are invincible. And I think it was the youth in me being a little too confident."
Heim has been chastened, but not chased off. He continues to search for shark teeth and has ramped up operations for his business, SHRKco.
His approach is different now. He's more cautious. He said he has more and better equipment. He's even been diving back in the Myakka twice since the attack. However, he now goes with other people, including gator experts.
Andrews said it's crucial for people to co-exist with alligators because they're an Indispensable part of the ecology as an apex predator keeping populations of other animals in check.
"In the South, they're part of our heritage. What a charismatic and iconic feature of our landscapes. It should be: We like our sweet tea. We like our grits. We like our alligators. This is part of who we are."