WASHINGTON—The U.S. Senate just passed the Big Cat Public Safety Act (H.R. 263, Senate companion bill S. 1210) by unanimous consent. This follows the bill’s passage by the U.S. House of Representatives on July 29. The legislation prohibits keeping tigers, lions and other big cat species as pets, and...

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...