Unsung Heroes of the Deep
If all of your knowledge about sharks comes from Hollywood movies like Jaws and Deep Blue Sea, then you know nothing about them. Hollywood movies tend to depict sharks as pure evil monsters having an insatiable hunger for human flesh which drives them to devour dozens of ‘innocent’ human victims one after the other. While being violent and gory (in other words, satisfying… as a movie I mean), these movies are the complete inverse of reality. What’s even worse is that people generally don’t have a positive view of sharks. And why is that a bad thing?
Well, to put it in straight terms, the actual victims are sharks and the real monster is humankind.
Is that even a new thing for anyone?
Sharks have a long history; these magnificent creatures first appeared in oceans some millions of years ago. Over time, they have evolved as the ultimate predator of the aquatic ecosystem. They possess all the physiological attributes worthy of an apex predator. For starters, they have three rows of hundreds of serrated teeth in their jaws (the middle row is in use, the outer one contains worn out teeth and the inner one contains new teeth, ready to replace the ones in the middle row) to rip off the flesh of their prey. Another noteworthy ability of sharks is their sense of smell or olfaction: it is said that an average hammerhead shark can sense the presence of a single drop of blood (and even pinpoint its location) in ten swimming pools’ volume of water (maybe even more). Their heterocercal tail (having a bigger upper fin) provides extreme force to accelerate at high speeds underwater (any swimmer can appreciate this as it is harder to move underwater because of the viscosity of this medium). They can also sense the heartbeat of their prey! Yes, their heartbeat… sharks have a unique form of sense called electroreception, allowing them to sense the small electrical voltages generated when a heart beats, meaning that the prey cannot hide even if it is invisible to the eye. But does all of this mean that sharks are dangerous or evil? Or are they man-eaters? The answer is no.
Generally, sharks don’t eat humans. As a matter of fact, sharks were never even meant to be man-eaters (biologically) as they are millions of years older than humans (if they were supposed to eat humans, as a regular part of their diet, then how did they survive all those years?). Naturally, smaller sharks feed on fish and invertebrates whereas bigger sharks feed on seals, sea lions, smaller sharks, and fish. It is true that some sharks are known to attack humans but those are just about a dozen out of more than 375 shark species. A provoked attack is understandable; someone messes with a shark and pays for it (as it should be). But what about unprovoked attacks? Well, these attacks usually occur due to confusion or curiosity on the side of the shark which may see a human splashing in the water and try to investigate, leading to an attack.
Before blaming sharks for these attacks, let’s just consider how these attacks usually happen. One fact mostly ignored by shark haters is that it is very rare for sharks to actually repeatedly attack an individual and/or to devour him completely, usually, these attacks are hit and run. The shark bites off a part of its victim and then leaves, but why? The answer lies in the reason for attacking in the first place and that is usually food, as mentioned above, sharks like to eat seals and other aquatic animals, and a swimmer swimming on a surfboard or a water float appears just like a seal or turtle from underneath. The rest is simple to understand, the shark thinks of its human victim as its natural prey and attacks, it takes a bite and realizes that it tastes different from the usual and once it has realized that it is a completely different animal, it leaves. Sharks, like all other animals, follow their instincts and as predators, they have to hunt down prey. The reason that humans get attacked is that they are intruding in a place where they don’t naturally belong. Humans are terrestrial beings hence sharks are not acquainted with them; they simply mistake them for just some other seal or turtle. Most human deaths that happen as a result of shark attacks are not because the victims were eaten but because of excessive blood loss.
That being said, how often do these attacks happen? Or what are the chances of being attacked by a shark?
Before answering this question, ask yourself this: how many times have you or people you know been attacked by sharks? For most readers, the answer would be never. As a matter of fact, the chances of being attacked by a shark are one in three million (some say: one in eight million). In 2017, there were 88 unprovoked shark attacks and five of them proved to be fatal. But another factor to consider is the number of people who enter the sea every year and that is in the billions. Out of billions of people who enter marine waters every year, only a handful are attacked. In fact, it is more likely for one to be injured by a toilet seat than being attacked by a shark. Being struck by lightning, being hit by an asteroid, being involved in a car accident, or being legally executed are more likely to kill a human than a shark attack.
People, in general, tend to be scared of sharks and consider them evil and that is because they don’t understand them very well. People don’t think that sharks even serve a purpose in their environment, but as a matter of fact, they do. Sharks are the apex predators of the marine food chain. This means that they are responsible for maintaining healthy marine ecosystems by controlling the population sizes of other organisms directly (by hunting them) or indirectly (by hunting their predators). Every ecosystem has a ‘saturation’ point, which is the maximum population size that it can sustain; apex predators are responsible for making sure that the population sizes of various species never exceed the saturation point.
The bitter irony is that the actual victims are sharks and man is the offender. Sharks are blamed for attacking humans and while it is true that they do so, the exact reason has already been explained. Man on the other hand kills about a hundred million sharks on average every year! Sharks have suffered immensely from overfishing (for their body parts, i.e. where do you think cod liver oil comes from?), many lose their life by being entangled in a fishing net as by-catch, and the worst and most painful death comes from finning. Sharks are caught, their fins are removed (cut off to be exact) and the carcass is tossed back into the sea (while the shark is still alive!). The shark's body sinks to the bottom where it dies a slow and painful death (if it is lucky, it’ll be eaten by other sharks, to make death quick). Finning is more devastating than fishing because the fins don’t occupy as much space as the complete body, which means a lot of sharks can be finned in one go. And why do we need the fins? For a soup! Shark fin soup uses shark fins for texture, yes texture: the fins don’t even add any taste to that pathetic thing! What makes this even more destructive than it already is, is the fact that sharks mature very slowly (sometimes as long as 15 years, as is the case with the lemon shark — Negaprionbrevirostris) and their reproductive rate is not impressive, as a matter of fact, most sharks give birth to just one or two babies and then they skip a year before reproducing again.
The overexploitation of sharks is leading to a steep drop in their population as the death rates of sharks are exceeding the capacity of shark populations to replenish the lost individuals. All of this is meaningless killing and yet we think of these innocent beings as devils. Do think for a moment, how many people die because of other people… The answer is: “many;” it is man who is bloodthirsty, man who destroys for no reason, and man who kills without mercy.
Sharks need saving, because, without them, the entire marine ecosystem will collapse. It is a rule of nature that bigger animals eat smaller ones and it applies to sharks as well. Sharks eat small fish which in turn eat smaller fish, the ones that feed on algae and phytoplankton. So if there were no sharks then the smaller fish (algae feeders) would be wiped out because their predators were prey to sharks. This would lead to the uncontrolled growth of algae and other plankton. This population explosion of algae (algal bloom) would lead to the deaths of aquatic animals in massive amounts, and that would mean an end to seafood. Some sharks such as hammerheads (Sphyrna species) feed on rays which in turn feed on scallops, so if there were no hammerheads, the rays would finish off all scallops leaving none behind for them and us to feed (scallops are a seafood delicacy in many countries). Sharks also feed on sick fish (usually these are easier to hunt), hence preventing disease outbreaks in the marine populations of fish, so if there were no sharks, fish would suffer from disease outbreaks and we wouldn’t have any marine fish to feed on.
Despite all that the sharks do in order to maintain a healthy marine ecosystem, they are never accredited for their services; they are the unsung heroes of the deep. The notion that sharks should be feared can be easily proven wrong by taking a look at the International Union for Conservation of Nature’s (IUCN) ratings of the three most ‘feared’ sharks: The great white shark (Charcharodoncarcharius) is listed as vulnerable, whereas the bull shark (Carcharhinusleucas) and the tiger shark (Galeocerdocuvier) are listed as near threatened.
Sharks have been in the oceans and seas and guarded them for millions of years, and we are on the verge of wiping them from the face of the Earth in a hundred years. A world without sharks would be a world with dead seas and oceans. Sharks are the true sentinels of the marine biota and they deserve saving, they deserve our attention because the Earth has been their home for millions of years before we (humans) even came into existence.
Originally Published: WWF-P’s Quarterly Natura, Vol. 42, Issue #2, 2018.
