October 13, 2006—Elephants, rhinos, hippos, and giraffes wandering the savannas and steppes is for many people the iconic image of African wilderness. But Africa's largest animal doesn't roam the continent on land—it inhabits the oceans.

Humpback whales, once hunted nearly to extinction, have recently returned off the coast of Gabon in West Africa (Gabon map). Conservationists are now working to protect migration routes for the sea creatures, which travel from India to Africa to breed.

Join scientists as they ply the waters in search of these singing giants, and watch as one researcher employs an usual tool in his effort to collect information about the whales—a crossbow.