Due to sensationalised stories and movies (we all know JAWS) sharks have become a feared killer within our oceans. But are we misjudging them? For Shark Awareness Day, 14 July, Griffith Shark Ecologist Johan Gustafson busts five common myths about sharks and tells us why he is so passionate about shark research and education programs in Australia.
Shark Myth #1: Sharks are man-eaters
Sharks don’t hunt humans. Sharks are very curious creatures. Where we use sight, touch and smell, sharks will bump, observe and take an inquisitive bite. It is common for sharks to bump, test bite and investigate driftwood floating in the ocean. This is why there are so many more bites than fatalities. These bites look more aggressive than they are because shark teeth point inwards, human skin is very fragile compared to shark skin and our natural response is to pull away.
Shark Myth #2: Sharks aren’t vital to our ecosystem
Sharks play a vital role in keeping marine ecosystems balanced and healthy. As the apex predators of the oceans, sharks control other marine animal populations and remove weak and sick species. This helps to keep ecosystems healthy and regulates grazing pressure on coral reefs and seagrass.
Sharks also help the economy, ecotourism and fisheries.
Shark Myth #3: Shark attacks are common
Shark attacks are not common. In 2019 Ocean Conservancy listed a few things that are more likely to happen to you than getting attacked and killed by a shark (1 in 3,748,067):
- Being hit by lightning (1 in 700,000)
- Being killed by fireworks (1 in 340,733)
- Becoming a millionaire (1 in 55 for millennials)
- Being dealt a royal flush in poker (1 in 649,740)
- Winning an Olympic Gold medal (1 in 662,000)
Here is a great infographic that compares other animals that account for more fatalities than sharks, with the main culprit being the mosquito!
Shark Myth #4: Sharks have no predators
Humans pose the greatest threat to sharks, killing around 100 million sharks each year. Sharks are fished for their meat, liver oil, cartilage and valuable fins, and for sport. With slow growth and reproductive rates, it can be tough for shark populations to recover.
The Orca is the top predator of sharks, they actively hunt and kill large white sharks. They are even able to surgically remove just the liver from white sharks. You can read more about this in the Smithsonian Magazine.
Shark Myth #5: We can never be safe from sharks
We can minimise the risks associated with shark attacks if we educate ourselves about our environment and make informed decisions:
- Be aware of environment cues – for instance, Bull sharks travel upriver after significant rainfalls of 60mm or more, as they are attracted by the refreshed river
- Know the most common species in the area
- Understand migration habits – like whales and dolphins, sharks have migratory patterns
- Swim at patrolled beaches
- Check local area alerts / reports
- Don’t enter water near commercial fishing vessels such as trawlers – fish in distress and the on-board processing of fish attracts sharks
- Don’t go surfing or spear fishing in murky water
- If really concerned, use repelling devices
- Follow the data rather than the myth.
Shark research and education are vital for reducing fear and understanding how to coexist with these sea creatures. Johan Gustafson shares his insights and experiences with sharks and shares advice on those interested in studying Marine Science.
Q&A with Johan Gustafson
What sparked your passion for shark research?
I was studying Medical Science. At high school I used to read medical encyclopaedias and I loved science, particularly biology. One of my early assignments was on the Ebola virus and the genetics behind it. So going into medicine seemed logical.
Volunteering at university however really helped me decide what I wanted to do. And it is a recommendation I give to all students. Volunteer – go beyond the words in the university guide and talk to people, try different paths. My volunteering work led to work in marine science and 12 hours shadowing doctors in an ambulance. I discovered that medicine felt quite repetitive for me whilst science was more challenging.
Sharks provide the biggest challenge as they are much understudied in Australia. Sharks also are hard to study because they move vast distances and live in great depths, open pelagic zones (open ocean) and even under the ice.
Why did you focus on Hammerhead sharks?
My PhD on Hammerhead sharks in Queensland was initiated by the Fisheries Department asking questions about catch numbers in their shark control program. They were puzzled as to why shark numbers oscillate so dramatically, decreasing by 50% one year then increasing the next two.
There is a distinct lack of shark data in Australia but also the data is different along Australia’s coastline. With no reliable method of monitoring or understanding sharks, how do we know whether or not more people are being bitten or whether or not there are more sharks in our oceans.
Why is shark education so important?
Because like the crocodile and the box jelly fish, it is really important to view sharks in context; sharks are wild, curious animals and we are all interlinked. Before massive educational programs crocodiles and the box jelly fish were viewed with fear and as dangerous creatures. Now, through education, we have a better understanding and live with them through informed choice. Their place in our environment has been ‘normalised’. It is this sort of educational program that will ‘normalise’ the existence of sharks for us.
Besides delivering online talks on the Hammerhead shark, I also educate through ‘Science on the Go’ events and Department of Education talks to school students across Queensland. For National Science Week this year I am holding online chats for female STEM students. I also feature on multiple programs such as National Geographic and Discovery.
What advice do you have for students interested in marine science?
My advice to students is to:
- Ensure you take the time to really articulate what you want to do or achieve – you can’t just say that you like animals
- Be prepared for a long road ahead– even with a PhD it is a very competitive field
- Diversify for longevity – I have a Masters degree in fish behaviour and oceanographics and recently conducted an ecological survey for the new cruise ship terminal at the Gold Coast
- Be aware that you will need to be a multi-talented scientist – commercial licences for boating and diving, instrumentation technician eg. satellite tracking systems, tradesman, statistician, computer software and coding expert, writer, educator, media guru
- Acknowledge the reality – only 10% of your time will be in the field
- Volunteer – expand your knowledge and your network
- Have passion
Johan Gustafson is a marine ecologist, looking at the entire ecosystem and the species interaction within the ecosystem. He studied medical and biological sciences at Griffith University and has consulted for the University as well as private and government departments. Read more about his projects and research or check out his work in the media.
Learn more about sharks through our open access research on Griffith Research Online:
Decline of coastal apex shark populations over the past half century
Future Research Directions on the “Elusive” White Shark
Rainfall and sea surface temperature: key drivers for occurrence of bull shark, Carcharhinus leucas, in beach areas
Nearshore movement ecology of a medium-bodied shark, the creek whaler Carcharhinus fitzroyensis
Non-lethal assessment of reproductive characteristics for management and conservation of sharks
A global perspective on the trophic geography of sharks
Habitat Ecology of the Bull Shark, Carcharhinus leucas, on Urban Coasts in Eastern Queensland, Australia
Habitat features influence catch rates of near-shore bull shark (Carcharhinus leucas) in the Queensland Shark Control Program, Australia 1996-2012
Access Griffith Research Online for more research on sharks.