Terror in the Oceans, Summer of the Shark 200?
Bob: "Why are the sharks suddenly biting people and killing them in the ocean near busy beaches of all places?
Nancy: "We'll have two marine biologists after this break."
Bull sharks have an undeserved reputation for not killing people.
You hear about the great white, tiger, mako, white tip, and hammerhead. At least the nurse shark has an appropriate name. Only #4 (disregarding common sense, below) could get one of those to turn on you.
Bull sharks aren't friendly neighbors. "They're a critical part of the ecosystem...yadda...yadda." That's all true, but we are part of the food chain allowing them to inhabit the ecosystem.
According to the International Shark Attack File (ISAF) bull sharks are historically responsible for at least 69 unprovoked attacks on humans around the world, 17 of which resulted in fatality. In reality this species is likely responsible for many more, and has been considered by many experts to be the most dangerous shark in the world. It's large size, occurrence in freshwater bodies, and greater abundance in close proximity to numerous human populations in the tropics makes it more of a potential threat than either the white shark or tiger shark. Since the bull shark occurs in numerous Third World regions including Central America, Mexico, India, east and west Africa, the Middle East, Southeast Asia, and South Pacific Islands, attacks are often not reported. The bull shark is also not as easily identifiable as the white or tiger shark, so is likely responsible for a large percentage of attacks with unidentified culprits.
Note the "occurrence in freshwater bodies," the only shark to do so. Consider where bull sharks live in the ocean.
The bull shark prefers to live in shallow coastal waters less than 100 feet deep (30 m), but ranges from 3-450 feet deep (1-150 m). It commonly enters estuaries, bays, harbors, lagoons, and river mouths. It is the only shark species that readily occurs in freshwater, and apparently can spend long periods of time in such environs. It is not likely that the bull shark's entire life cycle occurs within a freshwater system, however. There is evidence that they can breed in freshwater, but not as regularly as they do in estuarine and marine habitats. Juvenile bull sharks enter low salinity estuaries and lagoons as readily as adults do, and use these shallow areas as nursery grounds. They can also tolerate hypersaline water as high as 53 parts per thousand.
I've seen shots of surfers on the East Coast of Florida circled by bull sharks as the helicopter films, also circling overhead.
Note #4 below:
#1 Avoid swimming near river mouths or other estuaries with turbid waters where bull sharks are known to occur.
#2 Do not swim near schools of fish in inshore areas. These schools are often pursued by large predators.
#3 Be cautious if spearfishing. Bull sharks are known to approach spearfishermen carrying their catch.
#4 Do not duplicate the practices of some television "adventurers" who flagrantly disregard common sense for showboating around sharks while underwater.
Jeremy, who disregarded common sense as a recreational diver, knows everything about bull sharks after that really exciting macho ecotour he paid for.
"Bull sharks have the most fearsome reputation for shark attacks, yet you can flick a hand at them and they will retreat," observed Jeremy.
Jeremy was able to conduct this experiment once and therefore the full range of bull shark behavior had been analyzed for the purposes of selling more dive trips.
The Bull Shark
It lurks in the shallows, even in fresh water. And it loves to kill.
Loves to eat is more like it. Bull sharks are all muscle.
By Douglas McCollam
Posted Wednesday, July 18, 2001, at 12:00 AM PT
On July 6, as 8-year-old Jessie Arbogast waded in about 2 feet of water along Florida's Gulf Islands National Seashore, a 7-foot-long bull shark ambushed him, tearing off his right arm and a chunk of his right leg. The attack came so near to shore that Jessie's uncle and another beachgoer were able to grab the shark and drag it onto land where park rangers shot it, pried its mouth open, and retrieved the severed arm. The boy almost bled to death and lapsed into a coma. Surgeons reattached the limb, and though Jessie is showing signs of coming to, doctors say it's too soon to know if he'll make a full recovery.
Less than two months later Thadeus Kubinski, a retired businessman living near Tampa Bay, was attacked by a bull shark when he jumped off his backyard dock into five feet of water. His stunned wife ran to call 911. Kubinski died before help arrived. As I finished this story, the Associated Press reports that a man surfing just down the beach from the scene of the Arbogast attack was bitten while sitting on his board. He was taken to the same hospital, but his condition did not appear serious. The culprit wasn't identified, but the attack fit the bull shark's MO.
The mighty Great White would much rather eat an island seal than slum it at your favorite beach.
The bull shark possesses an indiscriminate palate: It will eat just about anything—other sharks, dolphins, and porpoises. (That stuff about dolphins meaning there aren't sharks around? Forget it.) Compared to their cousins the tiger and blue sharks—whose large, dark, disc of an eye make them such efficient sight hunters—the bull shark is as blind as Magoo. They often hunt in murky waters where visual acuity is less of a factor. Like all sharks, they command a keen sense of smell and can detect erratic movements from long distances. When zeroing in on prey, bulls use either a "bump and bite" technique to investigate the target or a more deadly rush attack where it delivers maximum damage immediately. As its stout build is complemented by disproportionally large jaws and teeth, the bull's bite is a deadly, shredding, vise.
Some day this will be a Trivial Pursuit question or maybe even Final Jeopardy so pay attention.
What animal has the highest testosterone levels?
Surprise, did you guess three-toed sloth? Well, it's the bull shark.