Happy Shark Week!
Sharks are the center of a lot of stories and urban legends, but you might be surprised by the truth behind some of the most common myths about sharks. In honor of Shark Week, we’re going to dispel some of the major myths surrounding sharks and shark behavior.
MYTH #1: All sharks are voracious predators, looking to attack anything in sight, including humans.
FACT: While some shark species do have aggressive tendencies, most hunt only to find food (and humans aren’t on the menu). Just like other top predators, sharks make a meal out of animals lower in the food web, keeping the ocean habitat in balance. Only a few species have been known to attack humans unprovoked, and that’s often because of poor visibility or inquisitive bites. There are even species, like the whale shark and the basking shark, that are filter feeders that eat fish eggs, krill, and other microorganisms in the water.
MYTH #2: Sharks do not attack at midday.
FACT: It’s true that there are fewer attacks in the middle of the day, but that’s not because sharks aren’t active then—it’s because everybody’s out of the water eating lunch. Sharks are most active at dawn and dusk, but it’s possible to encounter at shark at nearly any time of day.
MYTH #3: Sharks have walnut-sized brains.
FACT: Sharks are actually pretty smart! They have some of the largest brains in the fish world (along with their close relatives, rays), and their brain-to-body size ratios are similar to birds and mammals. Sharks have been known to exhibit complex social behavior, curiosity, and play in the wild. Many species live in groups and hunt in packs.
MYTH #4: In order to stay alive, a shark must constantly be moving.
FACT: The movement of swimming allows water to pass over a shark’s gills so that they can breathe, but some species have adaptations that allow them to stay still and breathe at the same time. When resting, some sharks can lie on the sea floor and actively pump water over their gills.
MYTH #5: Sharks have no predators.
FACT: Yes it’s true that sharks are at the top of the food chain, but they have a very powerful predator: humans. Each year, tens of millions of sharks are killed for their fins, sport, or caught and killed as bycatch. By removing so many of these important predators without allowing them time to restore their populations, we’re disrupting the balance of the marine food web.
The great white shark, the most iconic shark in the ocean, faces serious threats off the West coast of the United States. Only a few hundred are left, and their populations aren’t recovering quickly — unless we do something. Sign today to help improve protections for great white sharks in the Pacific.
We often tell you about the threats facing sharks globally -- finning, bycatch, overfishing -- but we don’t regularly shine a spotlight on the individual species affected.
To continue our ongoing shark-themed posts in honor of Shark Week, here are 10 of the most threatened shark species in the world:
1. Basking sharks are the second largest shark, easily distinguished by their huge, filter-feeding mouths. Basking sharks are caught in target fisheries around the world for their oil, meat and fins, and they are also caught as bycatch in other fisheries.
2. Blue sharks are one of the most previously abundant shark species. Now they are the most heavily fished shark in the world. An estimated 10-20 million individuals are killed by fisheries annually, mostly as bycatch. Blue shark meat is beginning to replace swordfish in many Mediterranean countries and the fins are commonly used in shark fin soup.
3. Deep-sea sharks have huge livers that contain high amounts of oil to regulate their buoyancy at depths. As a result, they are caught by deep-sea trawls, gillnets and longlines for an oily substance found in their livers called squalene. Squalene, or its derivative squalane, is found in many cosmetic products.
Only one more week until Shark Week!
So in preparation for the upcoming shark fest, today we will talk about the basking shark. Basking sharks are the second largest fish in the world. (Pop quiz - what is the largest fish in the world? I’ll give you a hint: I have already written a FOTD about this kind of shark.)
These sharks are filter feeders so they just swim around with their mouths open, collecting plankton and other tiny creatures while filtering out hundreds of thousands of gallons of water every hour. The water is filtered through the shark’s characteristically large gill slits on the sides of its head.
Check out Oceana.org/Explore for more shark info and see you tomorrow for another FOTD!
