I was born on the small island of Faial, one of nine islands in Portugal’s Azores archipelago in the middle of the north-eastern Atlantic. Having grown up just a few steps away from the ocean, I have been in the water since I can remember. My first steps as a naturalist and marine ecologist probably started when I was five or six, when I learned to use my brother’s snorkel. I would spend as much time as possible in the ocean, sailing, free-diving, fishing, swimming, playing, observing and learning. After graduating from high school, I moved to mainland Portugal to study marine biology and fisheries at the University of Algarve. During this period, I returned every summer to volunteer at the local marine research institute on my native island, where I did my final dissertation on the fascinating reproductive strategies and mating repertoire of the Azorean damselfish. Since then I have been involved in fundamental and applied scientific research, ranging from marine reserve science and fish ecology to artisanal fisheries, while developing diving and underwater photography skills. In 2009 I finished my PhD in marine ecology at the University of the Azores/University of California, Santa Barbara, where I investigated the implications of natural patterns of fish replenishment/recruitment on the design and sustainability of marine reserves. I have combined my background in marine technology and marine ecology to develop non-invasive tagging methods coupled with novel bio-telemetry tools that can be applied in the research into the ecology of marine megafauna.
Most of my work focuses on the Azores islands, an archipelago associated with the Mid-Atlantic Ridge in the north-eastern Atlantic, where the nine islands are the top of large sea mounts that have emerged from the sea floor at a depth of about 3,000 metres (9,840 feet). At a distance of about 1,400 kilometres (870 miles) from continental Europe and 2,000 kilometres (1,243 miles) from North America, the Azores is the most remote oceanic archipelago in the North Atlantic, where the oceanography is highly influenced by the Gulf Stream. This archipelago is a hotspot and a migrations crossroad for marine megafauna – including cetaceans, birds, turtles and more than 60 species of benthic and pelagic sharks and rays – that links eastern and western Atlantic margins and productive boreal waters and tropical seas.
Some of the animals visit mostly during the warmer months of June to November (such as tropical tuna and billfish, mobulid rays and whale sharks), but others apparently use the area throughout their lives (groupers and several deep-water sharks) or as a long-term nursery ground in which their juveniles can grow (blue, smooth hammerhead and tope sharks). Taken together, these taxa constitute by far the most vulnerable and protected group of animals in the region, including the terrestrial realm. Respectively 80%, 29% and 17% of the sea turtles, sharks/fish and marine mammals that occur in the region are classified as Critically Endangered, Endangered or Vulnerable by the IUCN and a large number of cetaceans and sharks/fish are still Data Deficient.
The presence of whale sharks in the Azores, the northern limit of the species’ distribution, has increased significantly in warmer summers over the past 14 years. Whale sharks and tuna normally occur together, as the large, slow sharks rely on the fast tuna to help them herd the small fish they feed on. In turn, the local pole-and-line fishers target these aggregations because they catch more fish when tuna are associated with whale sharks. Pole-and-line and other line-and-hook methods used in the Azores are highly selective, but the impact of targeting these feeding aggregations is unclear. We will use a multidisciplinary approach, coupling the analysis of historical data (from fisheries observer programmes and environmental remote sensing) with state-of-the-art biologging technology to investigate the trophic overlap and the fidelity and dynamics of the whale shark–tuna associations and to evaluate the potential impact of human activities. This project is expected to shed light on the impact of fishing on megafauna and contribute relevant information to support ecosystem-based management of fisheries and activities and to encourage smart decision-making for the conservation of the globally Endangered whale shark.