Dr. Marcus Drymon with the Dauphin Island Sea Lab seems pretty sure he knows what type of sharks they are.
"I'd feel pretty certain that they are bull sharks. Their pectoral fin base is very wide along with their dorsal fin base very wide and also just the shape of their nose very blunt," he said.
Robust-bodied and having a blunt, rounded snout, these are solid animals and are easily bulls of the ocean. The name also comes from them head-butting their prey.
I can’t tell if it would be less painful from the bowmouth, seeing as they don’t have spines… but those bull shark teeth…
The first dorsal fin is large and broadly triangular; the second dorsal fin is very small. The pectoral fins are large and angular. These animals are usually a dark gray, fading to white on the ventral side. These sharks don’t get as big as others (the largest being recorded at 3.5 meters or 11.5 feet), but they’re hefty in weight. They can weigh over 230 kg (500 lbs)! Dr. Neil Hammerschlag, research assistant professor at University of Miami, and the director of its R. J. Dunlap Marine Conservation Program and his team pulled up a 1,000 lbs giant up back in 2012.
“Did that say freshwater?”
You betcha it did.
Yep. I’ve now turned you off to taking baths, huh? Plug up your drains, friends!
Note: I’m 100% joking, by the way. About the drains, I mean. They really do go into fresh water. Sorry.
These sharks can be found in bays, harbors, lagoons and river mouths- they’ve been found up the Mississippi! Bull sharks have also been found very well into the Amazon River, and in Nicaragua been seen leaping into rapids to reach inland Lake Nicaragua.
The mental image I have in my mind is glorious. I’ll give you a hint: it reminded me of salmon, so I imagined a pink bull shark leaping into the air with a smile, crashing back into the glittery water.
Although many people think rays and sharks are solely salt-water animals, quite a few are found to frequent freshwater habitats. In fact, there are more than 30 species of shark or ray that spend some or all of their time in fresh water. It isn’t completely known why these animals developed freshwater tolerance, but one theory is that bull sharks needed a competitive edge for resources found in both freshwater/salt water (e.g. habitat, food). Ichthyologist Thomas Thorson studied bull sharks of Lake Nicaragua and discovered that these sharks regularly swam the Rio San Juan that connects Lake Nicaragua to the Caribbean Sea (remember the pink bull shark image). In this report, Thorson and his colleagues tested blood/body fluids of bull sharks for internal concentration of solutes (sodium, chloride, urea and TMAO). What they found was a loss of osmotic pressure due to a reduction of sodium, chloride and urea.
So THAT’S the secret. These animals adapt to freshwater by reducing concentration gradients! Neat, huh?
You also see that bull sharks have the third highest unprovoked human attacks (and here are 20 things that kill more people than sharks). According to Florida Museum of Natural History, there have been 67 non-fatal unprovoked attacks since 1580, with 26 proving fatal and 93 in total. This video is one of the more famous bull shark “attacks,” mainly because it was televised.
That this man states, “There was nothing I could have done” is false. The thing you could have not done is stand in the middle of a cluster of sharks.
But, go look at yourself in the mirror while working out at the gym. You and the person next to you are both at the gym, but that doesn’t mean you both have the same life histories. Example: your blood might be fine and they might be anemic. Both the same animal, bodies are just running differently.
Personally, I think more research should be done before anything definitive is said (although the bull shark raging testosterone levels is something that is widely said/accepted). I can see both points of the argument for/against saying this. After all, other sharks have shown high levels- Sphyrna tiburo had levels in the 300-400 ng/ml range.
Bony fishes and small sharks make up the vast majority of the bull shark’s diet. Other food items include sea turtles, dolphins, crabs, shrimp, sea birds and squid. Due to their large size, occurrence in fresh water, variety of prey and being known as aggressive, these sharks should be treated with respect and caution.
"[Bull shark] presence [in Alabama] shouldn't be an alarm to us at all. In fact, it should relieve us. We should be glad to see that shark populations are doing well. Relatively speaking in our area an ecosystem that lacks sharks is a very sick ecosystem, so we are very fortunate to have a thriving system in this part of the world," said Dr. Drymon.
What SHOULD worry you? A two headed bull shark.
According to reports, roughly six two-headed sharks have been documented over the years, but this was the first multi-headed bull shark to ever be officially recorded and documented.
Very cool, even if the baby died (realistically it couldn’t have lived)! Makes you think about all the spectacular things nature is hiding.
Thank you Reddit user sm3rsh for your “Submit a shark” submission! Bull sharks are one of the most interesting of the “charismatic” sharks and I absolutely love them. I got to witness a big one get measured up by Doc Gruber while I worked in his lab.
Here are a few pictures from that day: