Protected reefs bring little relief for sharks
Formal protection of the world’s coral reefs is not enough to sustain populations of their largest inhabitants.
A new survey reveals that top predators are missing from all but the most pristine habitats. Biologists have assessed almost 1,800 coral reefs around the world. Inevitably, sharks and other large predators such as snappers were almost entirely absent from reefs exposed to high levels of fishing and pollution. More surprising was that protected reefs close to high levels of human activity were also largely predator-free, even when fishing regulations are properly enforced.
Scientists suspect that such reserves are too small to safeguard large mobile animals, vulnerable when they stray out of the protected areas. The market-value of sharks’ fins make them an attractive target. More remote protected reefs contained four times as many sharks.
“It is in protected areas located where human pressures are generally low that sharks are most commonly found,” says Lancaster University’s Nick Graham. “Clearly these remote protected areas are important for shark conservation.” SB
For grey reef sharks, even protected reefs can be challenging.