Evansville’s Mesker Park Zoo built an artificial stream designed to fool a rare salamander species into using it for breeding.
The stream includes chillers and pumps to mimic a natural flowing river.
“We actually have to keep this water at a, not a constant temperature, unlike like the juveniles,” says Bryan Plis, a reptile and amphibian zookeeper. “We actually make it so that it goes up and down with the season. So, in the middle of summer, this water is 74, 75 degrees. The dead of winter, it’s hopefully going to be down into the 40s. And, at that time of year, they don’t eat, they don’t hunt, they don’t move much. They just kind of hunker down.”
The hope is that captive Eastern hellbenders will breed and lay eggs in the stream.
If they do, that would be a first for the species that’s North America’s largest salamander. Hellbenders can grow two or more feet long and live up to 30 years, but their numbers are shrinking in the wild. Dams and human habitats are segmenting their populations and making it so males and females can’t meet each other.
“They’ve been identified because they can’t be found,” Plis says. “So, their population was once high. And, they’re what we call an indicator species. So, if this species does well in the wild, that means the water quality’s good, the environment’s good, there’s an equilibrium between predator-prey, humans don’t have that much influence on them, things like that.”
Plis says there’s likely fewer than 50 Eastern hellbender salamanders living in the wild in Indiana.
The salamanders at the zoo aren’t full grown yet. The zoo plans to release them back into the wild as soon as they’re able to breed enough.