Editor’s Note: Earlier this year, we used social media to post condolences about the death of Rob Stewart (1979-2017), a marine conservationist and documentary filmmaker who died in a diving accident off the coast of Florida, at Alligator Reef. Stewart was best known for his 2006 documentary Sharkwater.
I recently watched Sharkwater, a documentary about sharks, and was immediately captivated by the beauty of the world under sea that Rob Stewart captured—as well as the devastation caused by the commercial shark fin industry.
Stewart once said, “Conservation is the preservation of human life on earth, and that, above all else, is worth fighting for.” In the course of the documentary, it’s clear that he believed this, because viewers witness some (though not all) of the challenges he faced while making the film—including risks to his life. He created Sharkwater as a way of raising awareness about sharks (and how, despite what the creators of Jaws and Sharknado might have us believe, they are not all that dangerous. In fact, you’re more likely to be killed by a vending machine than a shark.).
There’s a memorable scene where Stewart is on the ocean floor, cuddling a shark. There’s a breath-taking view of hundreds of hammerhead sharks schooling. There are also multiple scenes depicting the brutality of the shark fin industry, and statistics that will break your heart.
In the documentary, Stewart makes the compelling argument that sharks play a vital role in the survival of humankind, and life on earth as we know it. An understanding of how predators change landscapes indicate he’s probably right (think: reintroduction of wolves into Yellowstone).
Sharks, as Stewart points out, are apex predators and have existed for millennia almost unchanged. As apex predators, they provide evolutionary pressure to fish (and are likely the reason that some fish form tight schools, much as herd animals on land evolved to tighten up to avoid predation) and help maintain fish populations at a state that can be supported by the marine ecosystem.
This in turn helps ensure that plankton, which produce the majority (estimated 70%) of the oxygen we rely on, are not overconsumed. With fewer higher level predators, primary and mid-level consumers that include a heavy diet of plankton could cause the plankton population to crash.
That would not spell good things for the planet, or for us.
When Stewart died, he was reportedly making a sequel to Sharkwater. He also made the 2012 film Revolution and the 2015 film The Fight for Bala.
If you haven’t seen Sharkwater yet, and have the ability to access it (it’s available on a number of streaming services, including ones that do not require a subscription), take the time to watch it. The Sharkwater website also contains a teacher’s guide for teaching this film to secondary school students, which may also be useful for home viewing, especially if you watch the film with teens.