FORT LAUDERDALE, Fla. — A new shark-repellent device demonstrated in a viral YouTube video is drawing attention for what appears to be its ability to drive away dozens of sharks with a single blast.

For decades, sharks have been the unintended victims of longline fisheries aimed at tuna and swordfish. Rising accidental catches have contributed to population declines and created serious challenges ...

Eric Stroud is in the business of spoiling appetites. His clients include some of the most voracious creatures on the planet—the tiger shark, the reef shark and the southern stingray, to name a few.