There are economies that begin with extraction, and others that begin with astonishment. For centuries, humanity looked upon the sea largely through the first of these lenses: the ocean was a vast reserve from which fish could be taken, weighed, sold and consumed, its wealth measured in tonnes landed and prices obtained at auction. But the contemporary sea has complicated that arithmetic. A whale alive may sustain an entire economy of observation across decades; a manta ray moving through clear water can become the reason someone crosses an ocean; a shark, once regarded primarily as quarry or menace, may acquire another kind of value simply by continuing to swim. In the Azores, where the Atlantic has always been livelihood, frontier, mythology and destiny, this transformation is particularly visible. The same oceanic animal can now belong simultaneously to two economies: one that profits from its capture and another that depends upon its survival. Somewhere between the hook and the diving mask lies one of the great ethical and economic questions of our relationship with the twenty-first-century sea.
A scientific study published online in April and included in the August 2026 edition of Marine Policy brings that question directly into Azorean waters. Titled Watching or Catching Sharks: Tracing the Emergence of a Marine Resource Conflict in the North Atlantic, the study, by Björn Eriksson of Uppsala University and Wendell Medeiros-Leal, a researcher associated with OKEANOS at the University of the Azores, examines the relationship between shark-diving tourism in the archipelago and the high-seas fisheries that target—or encounter—the same highly migratory species in the North Atlantic. At the centre of the research are two animals: the blue shark (Prionace glauca) and the shortfin mako (Isurus oxyrinchus). The findings differ significantly between them. Blue-shark encounters have fluctuated but appear to have remained comparatively stable. The mako tells a darker story. Since shark diving began developing in the Azores around 2011 and 2012, operators interviewed for the study describe a striking decline in encounters with a species whose speed, elegance and rarity make its appearance one of the Atlantic’s most extraordinary gifts.
The figures are unsettling precisely because they translate ecological change into human memory. One Pico operator recalled that during the early years of the activity, makos appeared on approximately 72 percent of dives; within two years, the success rate had fallen to roughly 45 to 50 percent. By the more recent years covered in the interviews, the same operator reported seeing only three or four makos annually. Other professionals spoke of no more than four or five encounters per guide during an entire season. Operators on both Pico and Faial described the same broad impression: the mako that once appeared with some regularity has become an increasingly exceptional visitor. What disappears from an ecosystem often disappears first not from statistics but from expectation. There comes a moment when something once anticipated becomes something hoped for, and then another when what was once ordinary acquires the aura of an event.
The researchers are appropriately careful about what these observations can and cannot establish. This is not a new scientific census of Azorean shark populations conducted in 2026. The local component of the research is based on semi-structured interviews undertaken in July and August 2022 with eleven diving operators—three on São Miguel, four on Faial and four on Pico—combined with historical North Atlantic catch data, assessments of stock conditions and the evolution of fisheries-management measures. The authors themselves acknowledge the absence of systematic long-term observational series maintained by diving operators and recognise the inevitable limitations of human recollection. Memory is evidence, but it is not instrumentation. Yet when the testimony of those who repeatedly enter the same waters begins to correspond with what broader fisheries science is documenting across the Atlantic, anecdote becomes more difficult to dismiss. The authors conclude that the decline in mako sightings is consistent with the condition of the North Atlantic stock and identify overfishing as the probable causal explanation for the pattern observed in the Azores.
And here the story becomes larger than sharks.
For what the research describes is, fundamentally, a conflict between competing definitions of value. A shark caught on a longline becomes a commodity once. A shark encountered alive may become an economic resource repeatedly, without being removed from the ecosystem that produced it. According to the figures used in the study, the average first-sale value of blue-shark meat was approximately US$1.90 per kilogram. A single participant in an Azorean shark dive, by contrast, paid between €165 and €195, with as many as eight clients entering the water simultaneously under the supervision of a guide. The authors wisely resist converting these numbers into a simplistic equivalence. Fishing and tourism have different costs, labour structures, markets and economic chains. Yet the juxtaposition remains intellectually provocative because it asks us to reconsider an ancient assumption: must the economic value of a wild animal necessarily begin with its death?
In Faial and Pico, the question is no longer theoretical. At the time of the interviews, six of the eleven operators surveyed—four on Faial and two on Pico—actively offered shark-diving experiences, while another Pico operator had previously done so. One Faial entrepreneur estimated that shark diving generated approximately 30 percent of the company’s revenue. Blue sharks, in particular, offer something essential to wildlife tourism: a relatively high degree of predictability, with some businesses able to advertise sighting probabilities approaching 90 percent. Tourism built around wild nature always contains uncertainty; indeed, part of its beauty lies precisely in the fact that the animal owes us no appearance. But commerce requires some measure of expectation. People will cross continents for the possibility of wonder, but businesses cannot indefinitely sell an encounter that almost never happens.
The growing rarity of the mako therefore introduces a subtle form of impoverishment. For now, according to the study, there was no demonstrated evidence up to 2022 that high-seas fishing had caused direct economic losses to Azorean diving operators. That qualification is important and should not be lost amid the temptation to make the conclusions more dramatic than the evidence allows. The effects identified were principally operational: longer periods searching for or attracting sharks and the consequent possibility of higher fuel and associated costs. The researchers’ concern is prospective rather than retrospective. If the decline continues, particularly for makos, the Azores may gradually lose part of their capacity to offer the predictable encounters upon which this specialised sector of marine tourism depends.
Yet economics alone seems inadequate to describe what is at stake. The shortfin mako is not merely a unit of potential tourism revenue moving beneath the surface. Nor is it merely biomass belonging to a fisheries stock. There is something impoverishing in a language that can imagine nature only after assigning it a price. Economic arguments are necessary because public policy inevitably deals in livelihoods, employment and competing uses of resources. But the deeper achievement of marine conservation is not that it discovers that an animal may be more profitable alive than dead. It is that it slowly teaches societies to understand that life possesses forms of value that markets can reveal only imperfectly.
The Azores occupy an unusually compelling place within this conversation. These islands have spent centuries learning the Atlantic through necessity. The sea fed families, carried emigrants away, returned others home, isolated communities and connected them to the world. Whaling once occupied an important place in that relationship. Men launched narrow boats from island shores to pursue animals considerably larger than themselves, and an entire culture of labour, danger, craftsmanship and courage grew around that pursuit. When commercial whaling ended, the whales did not disappear from Azorean cultural and economic life. The relationship changed. Observation replaced pursuit. The animal that had once been hunted became the animal people travelled thousands of kilometres to encounter alive.
There is a lesson there whose significance extends far beyond whales.
The history of human relationships with the natural world is not condemned to repetition. Economies can evolve. Cultures can preserve their memory without preserving every practice. An archipelago can honour generations who lived from extraction while imagining forms of prosperity based upon conservation. Indeed, perhaps islands understand this more urgently than continental societies because limits are visible here. An island teaches finitude simply by existing: land ends, water begins, resources are bounded, and dependence cannot indefinitely disguise itself as abundance.
The sharks complicate this lesson because they do not belong to the Azores in any conventional territorial sense. Blue sharks and makos are pelagic wanderers, inhabitants of an ocean that refuses the neat boundaries through which human beings organise political authority. The shark encountered by a diver near Pico may later move through waters where another regulatory regime applies; the animal protected in one jurisdiction can encounter a fishing line beyond it. Conservation of highly migratory species therefore exposes one of the central paradoxes of ocean governance: ecosystems are continuous where sovereignty is fragmented.
A shark does not know when it has crossed a border.
That simple biological fact makes international cooperation indispensable. The economic interests of an Azorean diving operator may depend upon fisheries decisions made far beyond sight of the islands. A community can behave responsibly toward a marine resource and still suffer from decisions taken elsewhere along that animal’s migration route. The Atlantic joins what politics divides.
This is why the study by Eriksson and Medeiros-Leal deserves attention beyond the specialised worlds of shark science, fisheries management or diving tourism. It describes an emerging marine-resource conflict, but beneath that conflict lies a much larger question about the kind of Atlantic economy the twenty-first century will construct. Will oceanic wealth continue to be measured predominantly through what can be removed from the sea, or will increasing importance be given to what remains alive within it? Can fisheries, tourism and conservation be governed not as inevitable enemies but as different participants in an ecosystem whose biological limits ultimately determine the survival of them all?
There is also another form of knowledge embedded in this research that should not be overlooked: the testimony of those who work repeatedly in the same waters. The diving guides of Faial and Pico are not substitutes for marine biologists, just as fishermen are not substitutes for stock assessments. But sustained human observation has scientific and cultural importance. A person who has entered the same ocean hundreds of times develops an archive of experience: when animals arrive, how they behave, what changes, what becomes uncommon. The absence of something can itself become knowledge. One notices the bird that no longer visits the garden, the fish no longer caught near shore, the whale whose migration shifts, the shark whose silhouette becomes rare beneath the boat.
Ecological decline frequently begins as a sentence spoken quietly by someone who remembers:
We used to see more of them.
The danger is waiting until that sentence becomes: We used to see them.
For the Azores, therefore, the mako’s disappearance from more and more dives should not yet be written as catastrophe; the evidence does not justify such rhetoric. It should be read as warning, invitation and responsibility. The study itself insists upon caution, acknowledging the limitations of its interview-based local data while placing those observations within the wider evidence of pressure on the North Atlantic stock. That intellectual restraint strengthens rather than weakens its central message. Conservation does not require exaggeration. Sometimes the gradual disappearance of an encounter is eloquent enough.
And perhaps this is ultimately a story about the meaning of encounter itself.
Anyone who enters the open Atlantic to meet a shark does something profoundly different from observing an animal behind glass. There is no guarantee, no curtain rising at an appointed hour. The human being enters another creature’s world and waits. Then, perhaps, a shape materialises from the blue—the unmistakable geometry of a shark moving with that ancient economy of motion perfected long before humanity appeared. For several minutes, two species occupy the same water. Nothing is taken. The animal eventually disappears again into the ocean.
And yet something has been gained. A memory. An economy. A reason to protect a place. Perhaps even a different understanding of the sea. The old arithmetic counted what returned to harbour. The new arithmetic must also learn to count what is still swimming. Because the true wealth of an oceanic society may ultimately reside not only in what the sea allows us to take from it, but in everything we possess the wisdom to leave alive.
Based on a story in Diário dos Açores–Photos from Wickpedia and National Geographic.