Have you ever heard of a rattlesnake without a rattle? The Catalina Island rattlesnake is the only known species of rattlesnake to not have a rattle, and it can only be found in the wild in one place – the tiny Isla Catalina off the coast of Baja California Sur, Mexico.
“A rattlesnake’s rattle is an adaptation they developed to let larger animals know they’re there and not to step on them,” explains Jessi Krebs, curator of reptiles and amphibians at Omaha’s Henry Doorly Zoo and Aquarium. “With the Catalina Island snake, for reasons we don’t know, the rattle became more of a detriment so they actually de-adapted it.”
It’s the not knowing why that worries Krebs. The Catalina Island rattlesnake is critically endangered, and one catastrophic flood on the island could wipe out the entire species in the wild, taking everything we could learn about it with it. “We think these snakes have a lot to teach us about adaptation,” Krebs says, noting that, in addition to the lack of a rattle, Catalina Island rattlesnakes have evolved to be one of two colors, cream or gray, but that the island itself is relatively monochromatic. Krebs says that the scientific community would love to know how this particular snake developed these two colors.
Along with the potential to unlock some of the mysteries of evolution, snakes have made vast contributions to the field of medicine. There are FDA-approved drugs derived from snake venom for high blood pressure, blood clotting and heart disease, with many others being developed for conditions such as prostate cancer, HIV and multiple sclerosis.
“When it comes to snakes, honestly we don’t know what we don’t know,” Krebs says – but he’s working on finding out a lot more. Thanks to a generous donor to the Omaha Zoo Foundation, the zoo has recently embarked on a rattlesnake behavioral study that involves 24-7 surveillance in the Western Diamondback enclosure. Each day, an intern or a keeper spends two-to-three hours reviewing the footage to understand the way the snakes interact with each other and their environment. Krebs and his team are hoping to gather information and compare notes with field studies about how the snakes in their care breed (courtship isn’t necessarily just male-female), take care of their young (in many cases, a second female will stay with the babies while the mother forages) and interact with the throngs of zoo visitors who pass by their enclosure every day (they are mostly unfazed, which Krebs says highlights how well they’ve adapted to the glass that separates them from people).
Krebs and his team also study male aggression in the snakes, which is a fairly common occurrence, although you’d never know it from their names. Marshmallow is the most aggressive of the bunch – to the point where he even inserts himself into combat between other toughies like Muffin, Rich and Guppy. “In the old days, they would have had names like Fang or Viper, but now we give them softer names to disarm them,” Krebs says. “We know not everyone is going to fall in love with snakes, but it’s our hope to educate people to the point where they see their value.”
And if you do fall in love with the Catalina Island snake (they’re quiet, rare and cute… what’s not to love?), you can be a ZooMama or ZooDaddy to one by clicking here.