Currents and pressure are part of the danger, but many animals ... of sea urchins are snorkelers who step on them thinking they are corals. One more reason to keep your hands and feet off reefs.

The return of apex predators such as sharks can restore critical ecological balance to coral reefs, creating healthier ...

In fact, their iconic streamlined form belies a homebody nature: They rarely stray more than a handful of miles from the reefs ... shark ecotourism can provide a lifeline to locals who depend on ...