Who I am
I am a native New Zealander, born in a country known for the progressive conservation of its wildlife, forests, coasts and oceans. Many summer days were spent on the beach, playing in the surf with my cousins. I am not sure how much of my interest in sharks is encoded in my DNA or how much arose from early experiences, but either way my family had a lot to do with it. We were always told to watch for sharks while we were in the water and those warnings seeded my fascination. Both my grandfathers shared my interest and we would spend hours talking about sharks. For their part my parents hunted down dusty, out-of-print shark books for my Christmas presents.
At university I studied zoology and ecology, subjects that hooked me. On the advice of a New Zealand-based shark researcher and friend, after my degree I set off to The Bahamas to work with a world-famous shark researcher and learn the trade from him. Having met my wife and research partner there, I decided that the USA would be my base. By then a friend had inspired me to study shark DNA, but I was also alarmed that sharks were disappearing as a result of overfishing to supply the Asian fin trade. As I obtained a PhD and started a faculty position at Stony Brook University in New York, I resolved that my research should be used to improve shark conservation.
Where I work
My research and outreach efforts take me all over the world and into diverse settings. Sometimes I find myself in Hong Kong’s dried seafood district, surrounded by bleached shark fins. A few weeks later I could be in a room somewhere in the Middle East, Latin America or Oceania teaching border control personnel how to identify dried shark fins. At other times I am in my office in New York, staring at DNA sequences on my laptop as I try to decipher the information hidden within the As, Ts, Cs and Gs on the screen. But I am probably happiest when I am on the water, savouring a slight scent of salt and bait on the breeze, waiting for sharks to find me – and hoping that I have selected a site where sharks are still to be found.
To research oceanic whitetips I have returned to The Bahamas, a nation comprising hundreds of low-lying islands that sit on top of a shallow bank and are bathed by the warm, clear waters of the subtropical Atlantic. With an economy intimately tied to ocean-based tourism, the people of The Bahamas pioneered diving with sharks as a maritime parallel of the African safari. They never established a large shark fishery and over the past two decades they have taken unprecedented steps to protect their sharks. It is perhaps these efforts that now allow my friends and me to conduct our studies of the iconic oceanic whitetip.
What I do
The oceanic whitetip is a shark among sharks. Built like a barrel and growing to more than three metres long, it is a true apex predator. As its name suggests, it has been forged by evolution to live in the open ocean, gliding through the empty blue on long, white-tipped pectoral fins. The vastness of the open ocean and the patchy distribution of prey make finding food a challenge, and early ocean explorers like Jacques Cousteau quickly learned how this endless search affected the oceanic whitetip’s disposition. Described as ‘the most dangerous of all sharks’ by Cousteau himself, the oceanic whitetip is bold and inquisitive and readily approaches divers. I have personally been in the water with many large shark species, including tigers, bulls and great hammerheads. None have approached me closer or with greater assurance than the oceanic whitetip.
Reports about oceanic whitetips written before the age of industrial fishing almost always commented on how abundant they were in offshore waters all over the world. As humans began setting baited hooks by the mile to capture tuna, roving oceanic whitetips became a common accidental catch, one that provided an unexpected bonus as the demand in Asia for shark fins to make soup grew. Oceanic whitetip populations began a downward spiral and the sharks, once common, suddenly became difficult to find. Worse still, they had never been researched in detail, which left us without key information – such as their migration and reproductive patterns – necessary to develop an effective plan to protect them.
In the past few years a team of scientists from universities, research institutions and private companies have come together in The Bahamas to learn about the oceanic whitetip. Having cobbled together a pilot expedition to Cat Island in the central Bahamas, we found that the species was still common in the deep water surrounding this island. This high-density ‘pocket’ of oceanic whitetips may still exist as a side effect of local policies designed to protect shallow-water sharks that were the subject of shark dive operations. With funding from the Save Our Seas Foundation (SOSF) and others, our team started in earnest to collect as much information about these sharks as we could.
As in most shark field research, most of our time is spent waiting. Once a shark arrives, however, we catch it, bring it alongside our vessel and fit it with a PSAT tracker. This small device measures light, temperature and depth for several months before self-detaching from the shark, floating to the surface and transmitting its data to orbiting satellites. From this data we are able to reconstruct where the sharks go throughout the year and what temperatures and depths they prefer. We also give them a physical examination to find out if the females are pregnant. By tracking pregnant females we hope to learn where the sharks of Cat Island give birth.
Although we have much still to learn, even our earliest results have helped shape international policies aiming to better protect these sharks. In 2013 the species was listed under an international treaty that restricts trade in wildlife products, which will hopefully choke off the trade in oceanic whitetip fins. Among my proudest moments as a scientist was when delegates from The Bahamas spoke out in favour of this trade restriction, citing our research results as the reason for their support. As more nations follow the lead of The Bahamas, I am becoming more and more hopeful that the oceanic whitetip will one day reclaim its position as the premier blue-water apex predator.