On a longline fishing boat off the Galapagos Islands, a concerned biologist working undercover as a cook films a horrifying scene. As the camera rolls, a blue shark is dragged upside down out of the water, a sharp hook piercing it through the roof of the mouth and out through the side of the face...

India leaps into his pool, pouncing on a purple plastic egg—his favorite toy, according to his caregivers. After a few minutes, the tiger ambles over to his watering tub. Instead of taking a drink, he plops in and closes his eyes in contentment. Although he’s young—roughly 10 months old on this June...