Who I amAccording to my mother, the first time I saw the sea I froze in awe and cried ‘Too much water, Mom! Too much water!’ I was two years old, city-born, and we were on the shore of the Gulf of Mexico, in that country’s Veracruz state. As she took me into the waves I began to cry. But all that changed when I was eight and had the opportunity to live by the same sea for a whole year. I fell in love with the ocean and used to daydream about being a scuba diver with my cousin Juan, while we played by the sea with toy submarines, divers and sea creatures. Sharks were always the biggest thrill, majestic, mysterious and, in a child’s mind, mortally dangerous. It wasn’t until I was about 11 that I saw my first real shark in an aquarium in San Diego. Sharks remained fascinating to me throughout my studies in marine biology at the Autonomous University of Baja California in Ensenada. However, I never thought it would be possible to become a shark scientist.
But life has lots of surprises. For my first job after graduation I was charged with generating the basic information needed for the sustainable management of the shark fishery of Yucatán – the defining moment of my career! Although I knew basically nothing about sharks, I immediately fell in love with them and spent nearly five years teaching myself all I could about shark biology, ecology and fisheries.
Now, 30 years, an MSc and a PhD later, I have become a shark expert. My passion for sharks and rays has taken me around the globe conducting field research projects, attending science, management and conservation meetings, acting as a consultant and providing training courses. Perhaps most rewarding of all was working with live great white sharks. I was responsible for initiating research into the migrations and movements of great white sharks in South Africa and New Zealand, in collaboration with local scientists and government organisations. During this time I made the greatest discovery of my career: we tagged ‘Nicole’, a female great white shark that travelled from South Africa to Australia in the first recorded transoceanic return migration for any shark species. Interestingly, that’s when I met my friend and the Save Our Seas Foundation’s current CEO Michael Scholl, who collaborated with us in the project and whose own research was instrumental in completing the cycle of Nicole’s return migration.
Although learning about this misunderstood, threatened and fantastically imposing fish was the highlight of my career, I have also worked in elasmobranch taxonomy and identification, fisheries data and assessment training, ecology and fisheries modelling, conservation and management.
Where I workI have been lucky enough to work with sharks and rays while living in nine different countries (talk about a gypsy lifestyle!). However, my current gig has me dividing my time between Brazil and my native Mexico.
Our main study site in Brazil is an amazing, remote and inhospitable place of great beauty. The Archipelago of St Paul and St Peter sits right on top of the Mid-Atlantic Ridge, almost halfway between the easternmost tip of Brazil and West Africa – literally in the middle of nowhere! This equatorial rocky outcrop hosts a great diversity of marine life: dolphins, whales, tunas and jacks, billfishes, sharks and at least two, if not three, species of devil rays (Mobula tarapacana and M. thurstoni) and one of manta ray (Manta birostris).
The islets’ barely 15,000-square-metre jagged surface of pure volcanic rock offers no easy footing for walking around and no protection from wind or sun. There is no fresh water and we have to bring every single piece of life-support and research equipment and all our food and water on a gruelling three-day boat trip from the Brazilian port of Natal. But the research station and accommodation built here by the navy has incredible facilities, including electricity, satellite phone and of course Internet (slow and iffy, but Internet nonetheless!).
With its abundant and pristine marine wildlife, this is a unique place for research – and adventure. Just a few metres from the shoreline, the sea floor drops to a depth of more than 4,000 metres. There are numerous pelagic species, including marine turtles, which are a common sight around the islets and in the inlet, the archipelago’s only shallow section. Working here and studying the majestic devil rays is truly a thrill and a privilege!
Our Mexican field site is another fabulous place: the Whale Shark Biosphere Reserve at the edge of the Gulf of Mexico/Caribbean transition zone, just off the north-eastern coast of the Yucatán Peninsula. Every summer, this very special place hosts the largest known aggregation of whale sharks in the world. Because of this it also attracts large numbers of ecotourists – and they in turn bring additional threats to the ecosystem. The area is also known for its great biodiversity, which includes marine mammals, manta rays, devil rays, spotted eagle rays, various shark species, rock lobster, shrimp, four marine turtle species, many seabird species and large schools of sardines and anchovies, as well as hundreds of species of reef, pelagic and bottom fishes, and echinoderms, polychaetes and other marine invertebrates.
What I doOur project combines ecological and biological research with conservation efforts. We are hoping to unveil the mysteries of devil rays: how they use different parts of the ocean and where they migrate to. We also compare the behaviour of ray species in each site and contribute to a global study led by the Manta Trust into the number of species, the relationships between different populations of devil and manta rays, and how these are exploited to supply the trade in their gill plates.
In recent years, the belief has arisen in China and eastern Asian countries that manta and devil ray gill plates possess magical powers to cure all kinds of human ailments. The trade driven by this dubious ‘traditional Chinese medicine’ is fuelling a huge increase in the fishing of these beautiful marine giants around the world. Brazil and Mexico have passed legislation protecting all manta and devil rays from fishing, but there are many other countries that have not joined this important conservation movement. We need to gather enough scientific evidence to convince these countries, as well as international conventions that regulate trade (such as CITES) and exploitation, that all manta and devil rays should be protected with as many types of legislation as are needed. This is why it is crucially important for their conservation that we discover where the rays go during each phase of their life cycle; how many species there are and how to recognise them; and where and which populations of each species are being overexploited.
During our field trips we deploy cutting-edge electronic satellite tags that measure depth, water temperature and light levels every few seconds. The information from the tags is relayed to us via satellites, enabling us to follow the movements of each individual ray for several months at a time. Both difficult and exhilarating, tagging the devil rays involves free diving with them in order to attach the tags to their backs by means of small darts. The tags detach automatically after a pre-programmed period and relay the information to our laptops at home. During our field trips we also try to measure and sex each individual and obtain small samples of its muscle and skin. These samples will enable us to conduct population genetic and taxonomic studies that are essential for mapping how many different species exist, their physical differences and which populations are being exploited for the gill-plate trade.
As I go to sea during each expedition, I am always filled of joy and awe at the spectacle of swimming alongside these beautiful ‘flying’ sea creatures. I truly hope that with the combined efforts of everyone, we will preserve them for future generations to admire.