Coastal residents around the world have heard some far-fetched myths about sharks, but some are actually believed to be common knowledge. In order to preserve the creatures and stay safe while in the ocean, humans need to know the facts about the myths.
Myth: All sharks are the same and hunt humans
Fact: According to oceana.org, there are approximately 500 shark species with variations in size, shape, habitat, diet and behavior. Only 3 sharks (white, tiger and bull) are responsible for the majority of bites. Two of the largest shark species, whale and basking, are filter feeders and eat fish eggs and other tiny organisms. Sharks do not hunt humans and most encounters are mistakes due to poor water visibility or are inquisitive bites, which is why there are more bites than fatalities.
Myth: Sharks prefer human blood
Fact: Most sharks do not appear to be especially interested in the blood of mammals as opposed to fish blood, according to mote.org.
Myth: Sharks must stay in motion to stay alive
Fact: While it is true that sharks must swim to breath and keep water flowing over their gills, some have the ability to pump water across their gills by opening and closing their mouths while resting on the bottom, according to masgc.org.
Myth: To prevent a shark from attacking, punch it in the nose
Fact: According to masgc.org, a shark's nose is a very sensitive organ, but the skin is also very thick. In addition, it is difficult to punch underwater, because of the water resistance. The resistance makes it difficult to use enough force and the act would most likely just upset the shark. Instead, aim for the gill slits or their sensitive eyes to prompt the shark to go elsewhere.
Myth: Black wetsuits make surfers look like seals
Fact: "The typical white shark you will find in the surf zone in NSW [New South Wales] is 2.5 meters or below, but white sharks feed on seals for only a very small part of the year and it does not become part of their diet until the shark is at least 3 meters long," said Dr. Barry Bruce, a great white shark expert for the Commonwealth Scientific and Industrial Research Organisation in Australia.
Myth: Sharks are only found in the ocean
Fact: Many bodies of water are linked to the ocean in some way and sharks have been found in the connecting brackish water areas, which are a mixture of salt and freshwater. Also, according to mote.org, a specialized osmoregulatory system enables the bull shark to cope with dramatic changes in salinity and can even be found in freshwater rivers.
Myth: Shark nets equal safety
Fact: According to sharkattacksurvivors.com, the nets placed among popular beaches to denote a safe swimming are not a barrier from the rest of the sea. They are simply a series of smaller nets that can be moved to certain locations.
Myth: Attacks are more common in specific conditions
Fact: "We have looked at everything -- El Nino, La Nina, water, temps, food sources, the southern ocean oscillation index and nothing really adds up. It's one of those things yet to be explained," said Dr. Vic Peddemors, a leading shark attack investigator.
Myth: Shallow water is safe
Fact: According to masgc.org, a shark attack can occur in as little as two feet of water and tiger sharks especially, have been known to follow prey into shallow water. In general, if the shark is small enough to swim there, it can attack. Also, some shark species use the shallow waters as a nursery for their young.
Myth: Sharks have poor vision
Fact: Sharks' eyes have the ability to distinguish colors, according to masgc.org. They have a lens up to seven times as a powerful as a human's. Some shark species can even perceive a light that is as much as ten times dimmer than the dimmest perceivable light by humans.
Myth: Sharks are stupid and have walnut-sized brains
Fact: Sharks can exhibit complex social behaviors and some species can communicate with body language, according to oceana.org. Their brain-to-body ratio is similar to mammals and birds, and they have some of the largest brains among all fish.
Myth: Urine attracts sharks
Fact: According to sharkattacksurvivors.com, many surfers are declining a morning coffee before hitting the waves in order to eliminate the necessity to urinate in the ocean, but there is no evidence supporting urine magnetizing sharks.
Myth: The great white shark is common and found off most beaches
Fact: Great whites are relatively uncommon large predators that prefer cooler waters, according to mote.org, and in some parts of their range, are close to being endangered.
Myth: Sharks have no predators
Fact: According to oceana.org, human are the greatest threat to sharks, and each year, tens of millions of sharks are killed for their fins, which offer no flavor or nutritional value.
Myth: Sharks are unnecessary and harmful creatures
Fact: Sharks play a vital role in maintaining a balanced and healthy marine ecosystem, according to oceana.org and assist in ecotourism for coastal economies since many people are willing to pay for the expensive opportunity to dive with the sharks.
First Coast News