For a new project, National Geographic's Joel Sartore has photographed over 6,000 species held in zoos, sanctuaries and other captive institutions across the world because they're "the animals we have."
Starting Thursday, the Dallas Zoo will have a selection of Sartore's work from his "Photo Ark" on display through September. The Dallas Zoo is one of three zoos in the country hosting the traveling exhibition.
Sartore stopped by the KERA studios to talk about his project.
On photographing animals in captivity:
There are about 12,000 to 13,000 animals in human care around the world at zoos, aquariums, wildlife rehab centers, captive breeders. And they represent a really good cross-section of what biodiversity looks like at this point in time because zoos high-graded; they collected and started breeding the animals that are fabulous in terms of what they do and what they look like and how they sound.
On connecting with these creatures:
I feel very honored, and there’s a lot of pressure, actually, because I’m often the only one that ever gives them the time of day. Most of the animals I photograph are photographed dead alongside a ruler, maybe by the biologist that described the species, putting it in a museum. But there’s not really been anybody since. And I may be the first and only one that photographs them alive and looking normal. Especially when I travel abroad, I’m looking at the very last of their kind in a captive setting, the very last of them.

On how he got started:
My mother cared about wildlife, and so did my dad. My mom got me a Time Life picture book, and in that book was a picture of Martha, the last passenger pigeon, who died at the Cincinnati Zoo in 1914. And those birds numbered in the billions, and people market-hunted them to extinction. And I stared at that picture a lot as a kid — like really concentrated on that, would go back to that book over and over again just wondering how we could reduce something to extinction. How could we take a species like that and reduce it to rubble? And that is what drives me today.
Watch Dallas Zoo experts talk about their animals in studio
This interview has been edited for brevity and clarity.