The mountain lion known as P-47 survived fires, freeways and hostile ranchers. But in March, the 3-year-old big cat—tracked by California biologists since his kitten days—succumbed to a hidden hazard: an insidious form of food poisoning. Six anticoagulant compounds—chemicals used to kill rodents...

It seemed like a good idea at the time: Buy a house with a two-acre property, let our energetic herding dog have the run of the place and spend blissful summer days digging side by side in the dirt with her. And it was blissful, watching Mattie carve out her napping spots behind the ferns and tall...

Wherever you are in the U.S., a coyote may be taking up residence less than a mile away. If you live in the city, you’re more likely than your rural cousins to encounter raccoons. And regardless of geography, you probably share your home with dozens of species of insects and spiders. These facts...