Sunday 14 February 2016

Orca vs. Great White

Orca vs. Great White? You're truly desperate for blog posts now, Andrew!

I know, but whatever I'm truly into at one time, I like to write about. Call it hypergraphia, my friends. Marine biology has always interested me, and despite conflicting decisions over whether or not to study it and develop it as a career, I always enjoy looking at the latest facts regarding aquatic life.

Whales and sharks rank amongst my favourites, and arguably the most famous of each species are the Orca and Great White, respectively. The Orca is a remarkably intelligent, powerful beast that ranks as one of the strongest predators in the ocean, whilst the Great White is a much feared, infamous creature that garnered a reputation as a ferocious man eater after the release of the 1974 novel Jaws and it's 1975 film adaptation.

So, in another random blog post that just serves no purpose other than to write stuff that interests me, let's do a farfetched yet interesting comparison between two mighty beasts of the sea.

Flying sharks? No thanks.
The key difference is that Orca's are marine mammals (under the cetacean genus) whilst Great White's are, of course, fish. They look similar on the outside, but when it comes to their anatomy and behaviour, there are many massive differences. As we all know, cetaceans cannot breathe underwater - they lack gills, which fish use to filter oxygen out of the water so long as they keep moving. Cetaceans, on the other hand, have blow holes on their heads, which are connected to their lungs inside. These blowholes are used to inhale fresh air and allow the animal to maintain oxygen levels whilst swimming. Cetaceans need to hold their breath when diving for prey, which Orca's can do for up to 15 minutes, but they seldom submerge for more than five. Some others can manage much longer, notably Sperm whales, which can hold their breath for as long as 90 minutes.

Another noticeable difference between whales and fish is the tail - fish have a vertical tail whilst whales have a horizontal one, and this all relates to the evolutionary history of these animals. Mammals have always evolved to flex their spines in an up and down motion to move, which is why a horizontal, flat tail is far more beneficial for whales to navigate this way within the sea. Fish, including sharks, evolved from seabed creatures that slithered along the ocean floor, hence why their side to side movements require a vertical tail. Sharks rely on their fins for balance and movement, with the main pectoral fins helping with directional movement and the dorsal fin controlling overall stability when rolling and turning. Orca's have similar dorsal fins, but their frontal fins are known as "flippers", though they basically have the same function as pectorals.

Let's face it, as kids, we all thought that was it's actual eye.
Orca's are far larger than Great Whites, with adult males reaching up to nine meters and weighing up to four tonnes; their dorsal fin alone can exceed human height at around two meters. In contrast, the Great White usually gets to six meters upon reaching adulthood, and the average weight is usually just over one tonne, though some significantly larger specimens have been reported. Great Whites are solitary creatures, seeking prey in a stealthy manner and usually conducting surprise attacks to make quick, easy kills. They are commonly seen leaping upward to snatch unbeknownst victims, such as seagulls and seals, from the surface, in a dazzling act known as breaching. They are responsible for many unprovoked attacks on humans, further worsening their reputation as man eaters, and have also been known to resort to scavenging when the opportunity arises.

Orca's hunt in groups, communicating with a number of complex verbalizations and "clicks", unlike sharks which have no organs to produce sound and so remain silent but deadly in any situation. They typically feed on seals and, in rare cases, have even been known to hunt and kill Great Whites. Using their remarkable intelligence and problem solving skills, these whales have been seen pulling off all sorts of tricks to capture even the most stubborn victims, meaning there is little escape for those who are trapped. Such tactics can vary from making waves to wash prey off of ice flows, to literally throwing their victims sky high via their tails, sending them plummeting back down to a grizzly death. It's not easy to watch, but demonstrates a seriously admirable level of tenacity and skill.

Is it weird that I actually find their neutral expression kinda cute?
Great White's have never survived in captivity and cannot be accommodated by any aquarium, with the many experiments having the shark survive for a matter of weeks; most have ended with the shark being released back into the wild before it's too late. Many reasons for this have been explored: they require so much space as they naturally swim hundreds of miles a day, yet they will need a sizeable tanks all to themselves as they will kill any other animals who share it with them. They also refuse to be manually fed, are extremely dangerous to handle for even the most experienced people, and often become very depressed and weakened if aquarium water is not at the correct chemical balance or if their tanks, as previously mentioned, are too small to accommodate their lust for freedom and exploration. This in turn leads to self harm by headbutting their own tank walls and a severe loss of appetite.

Orca's are polar opposites in many ways, and have become both an enjoyable and controversial product of captive life. As we all know, SeaWorld is home to a collection of Orca's under the stage name of Shamu, which perform all sorts of shows alongside their trainers in front of hundreds of guests. It's truly impressive to watch, with the talent and strange sense of humour they show off continuing to remind us how much we take animals for granted when it comes to their mental abilities. However, these practices are also the subject of severe backlash - many deem it cruel and undermining to capture such exotic creatures and force them into performing tricks for entertainment, which is an understandable argument, and one that was further supported with the release of the 2013 documentary film Blackfish. Orca's have, on some occasions, attacked and killed their trainers, either on purpose during aggressive phases or while playing with them and not realising their own strength. 

But this is equally as cute to be fair.
Comparing them in terms of a head to head fight is both crude and pointless, but if you were to match up their stats, generally Orca's have a significant advantage. They are larger, stronger, more agile, and also much more intellectually equipped. Whilst both are considered apex predators, the Orca is noted by some to be, on rare occasions, the only predator of the Great White. The Great White has a monstrous bite force of over 600PSI, the strongest of any predatory fish, while the Orca's has yet to be officially measured. Some estimates, based on incidents with captive specimens, predict an absurd PSI of over 19,000 - which rivals that of the T-Rex, hence why such a figure is often debunked as a myth for beyond obvious reasons.

The conservation status of Orca's is referred to as Data Deficient, meaning that we do not know enough about their overall habitat, breeding status, and population to assess their natural wellbeing and security. In contrast, the Great White is listed as Vulnerable, mainly due to a history of shark finning that has grossly affected many other species as well. This involves capturing sharks and slicing off their fins before tossing their mutilated yet still conscious body back into the sea, where it dies from either suffocation, blood loss, or consumption by other predators. Slowly but surely, more countries are banning this practice, and many restaurants have been forced to remove Shark Fin Soup from their menus after aggressive protests and boycotts. Great Whites are also vigorously protected in some countries, mainly New Zealand, where the unlawful killing of one can result in a $250,000 fine and up to half a year in prison.

So leave the little guys alone.

Thanks for reading!