Ask an X-Pert: Shark Boi and Lava Pescetarians

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Words || Laura Fitchett

Did you know we have sharks on campus? Yeah, don’t worry, you’re not the only one who just heard the Jaws theme in their head. It is that immediate heart pounding, hand sweating reaction that directs the current of much of our cultural understanding of sharks.

This fear has resulted in shark culling programs across the country, as well as the use of shark nets and drumlines, which are baited hooks used to lure and trap sharks. This has resulted in some troubled waters for our native marine life. According to the Australian Marine Conservation Society, 577 great white sharks and 352 tiger sharks were caught in shark control nets in NSW between 1950 and 2008. Sharks are not the only animals getting caught up though, other marine animals that die in the nets are referred to as ‘by-catch’.

What by-catch really means is non-lethal marine life, such as turtles, whales, dolphins, stingrays, dugongs, and harmless species of sharks. Over the same time period 15,135 marine animals in the by-catch category were caught and killed in nets, including 377 critically endangered grey nurse sharks.

There has been a huge amount of debate about whether or not marine life such as fish and sharks feel pain. The pescetarian diet, which adds seafood to a vegetarian diet, is a popular alternative to vegetarianism that supposedly maintains ethical values. Scientific research has swayed in the direction that fish do not feel pain the way humans do.

However, Associate Professor at Macquarie, Culum Brown, who specialises in the behavioural ecology of fish and marine life, believes that just because they don’t feel pain the way humans do, does not mean they do not feel pain at all. “People tend to forget that the reason we feel pain is because we inherited all the gear from our fish ancestors. There is little doubt that bony fish feel pain in a manner similar to us.”

Culum has been interested in marine animals ever since he was a kid. “A few years back a post doc spent some time in my lab working of cognition in sharks and we have been working on them ever since.”

He works closely with our resident sharks here at Macquarie. His research is motivated by a need to understand their behaviour. “Sharks are reasonably cryptic and can move huge distances, and being marine it’s very hard to observe them for any decent length of time. Sharks are one of the most vulnerable of marine animal groups. They also have a bad rep in the press, even though they are responsible for fewer than one death per year.”

The cultural fear of sharks may be contributing to misconceptions about whether or not sharks feel pain. Culum says that while most of the appropriate experiments have yet to be carried out, pain receptors must exist within the physiology of sharks, since they date back to the annelids.

Even without a specific experiment to test pain reception, there are indicators that sharks have complex social structures, even best friends. “Sharks have complex social lives, far more so than we give them credit,” says Culum. “They preferentially hang out with specific individuals. We analyse this using social network analysis, which is a bit like keeping track of people’s Facebook accounts.”

This is done through acoustic tag technology, which allows researchers like Culum to figure out where the sharks go and what they do. Culum has tracked Port Jackson based sharks as they migrate all the way to Tasmania and back. They return to the same reef every year to breed, and develop complex social relationships with their peers.

These shark bois don’t sound all that different from doggos, well maybe with a few extra teeth. So why do so many people believe that it’s okay to cull so many different types of marine life? “People definitely treat fish as if they are in some way inferior to land animals. They are not,” says Culum.

We don’t know for sure if dogs, cats, chickens, or cattle feel pain the exact same way that humans do, but we are constantly campaigning for more humane and ethical treatment, as well as introducing legal penalties for mistreatment. If animals like fish and sharks are self-aware, in a way that is comparable to a chook, shouldn’t we treat them with just as much compassion? Culum is currently studying sense of self in wild mantas in Indonesia. His findings may well give a swell of support to our misunderstood shark bois and their ethical standing in society.