Saguaro National Park, Arizona–It’s reptile country here on the outskirts of Tucson, the site of the 2011 BioBlitz. As I write this, the 2,000 people who have fanned out across Saguaro National Park to identify all the species in the preserve have identified some dozen species of reptiles. I spotted one myself, right outside this very tent — a magnificent black snake with a bright yellow eye that a park ranger told me was a coachwhip.
Across from where I am sitting is perhaps the most popular table in the science tent. U.S. Geological Survey herpetologist Cecil Schwalbe has brought some live specimens, including a giant pink venomous lizard called the Gila monster, two tortoises, and a couple of non-venomous snakes.
In the video interview above, Schwalbe talks about all these reptiles, which are commonly found in Saguaro National Park. Some of the highlights:
— The Gila monster does not use its venom to kill prey, but rather as a defense against predators. Nonetheless, it’s not an animal you’d want to handle. According to Schwalbe, a bite from a Gila monster is like being sliced with a razor blade, and profuse bleeding is likely to ensue.
— How do desert tortoises prevent themselves from being baked by the sun inside their shells? Schwalbe says these animals are adapted to the harsh conditions and are masters at preserving every scrap of moisture. They can even retain their pee and poop to avoid voiding even the slightest bit of water.
— The king snake is so-called because it eats rattlesnakes. When a rattler encounters a human, it will often coil itself and be threatening. But if it sees a king snake it gets away as fast as it can. “They know the king preys on them,” he says.

David Braun is director of outreach with the digital and social media team illuminating the National Geographic Society’s explorer, science, and education programs.
He edits National Geographic Voices, hosting a global discussion on issues resonating with the Society’s mission and major initiatives. Contributors include grantees and Society partners, as well as universities, foundations, interest groups, and individuals dedicated to a sustainable world. More than 50,000 readers have participated in 10,000 conversations.
Braun also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship.