Out in the Atlantic Ocean, roughly 60 miles off the northwest coast of Africa, lie the Canary Islands. In the 1950s, the boom in package tourism showed promise as a new cash crop. But while the Canary Islands had the sunshine, warm climate and ease of access from Europe needed for this new industry, they were missing a vital element picture postcard sandy beaches.
So the developers on Tenerife in the Canary Islands constructed a breakwater (防波堤) over half a mile long. And then, from the Western Sahara on Africa's northwest coast, they shipped in 270, 000 tons of sand. By 1973, the project was complete. As anticipated, tourists arrived. Along the engineered beach, rows and rows of tourists relax on beach chairs under umbrellas or walk across soft sand to cool down in the water.
Unanticipated was what their presence gave to one of the world's most endangered fish species, angel sharks — visibility. The gentle wind creates tiny waves on the water's surface, a magical cover for what lies beneath — an angel shark nursery. Female angel sharks regularly migrate to these ideally sheltered waters to give birth to pups (幼崽), who remain in the shallows for about a year. Feeding on small fishes, they grow to around the same length as a newborn human baby.
Surveys have shown that other beaches in the Canary Islands are also potential nursery sites. Interestingly, most of them have been remade to make them more attractive to people. Playa Chica has another long sweep of imported sand. It's an attraction for divers as well as angel sharks, so the number of sightings of mature angel sharks of this shoreline is one of highest in the islands.
Normally, massive, environmentally disruptive projects are bad for wildlife. But what's clear is that after the breakwater was built and the sand arrived, people followed, and in the calm, shallow waters they began to see baby angel sharks. And unlike how many an association between humans and wildlife ends-in conflict and dead animals, this time it led to conservation.
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