Bullet Proof

Despite ample scientific evidence linking the use of lead ammunition to a host of environmental and public health threats, roughly 90 percent of the 10 billion rounds purchased every year in the United States still contain lead. That, reform advocates say, is absurd — if not downright negligent.

The Claws Come Out

Peter Marra’s new book, “Cat Wars,” makes a convincing case that unconfined felines are taking a major toll on wildlife — and putting the growing ranks of cat lovers and bird lovers on an ugly collision course. The war — call it Big Cat vs. Big Bird — is on. And right now, we’re all losing.

Furry Animals, Fuzzy Science

Turning college team mascots into icons of wildlife conservation seems like a winning strategy, but there is surprisingly little science to suggest that it can really help to protect species — particularly those that are critically endangered. Still, a growing number of schools are giving it a go.

Endangered: A Bird and a Tribe

The Blue-bearded helmetcrest is a vanishingly rare hummingbird, and until March of last year, it hadn’t been seen in the wild for nearly 70 years. I traveled to the high mountains of Colombia to see it for myself, and returned with lessons both unexpected and essential in the complex ethics of conservation.