Castor, the Denver Zoo’s 11-year- old Komodo dragon, scored a little love action with the help of a small band of humans.
Beth Jo Schoeberl, the zoo’s curator of primates and carnivores, joined the group just as Castor’s last clutch hatched in 2003. And Schoeberl will get to help decide if he mates again.
Schoeberl is the “studbook” keeper for Komodo dragons in zoos across North America, and her job – with the help of a committee – is to pair up male and female lizards.
This is, however, more than the reptilian version of “The Dating Game.”
The Komodo dragon is the world’s largest lizard; at 10 feet long and up to 500 pounds, an adult Komodo can take down a 1,000-pound buffalo. One bite from the Komodo’s bacteria-coated teeth can be deadly.
Despite their prowess, the lizards are endangered in their native range on the northern islands of Indonesia, where the population is estimated to be 1,000 to 5,000 animals.
The American Zoo and Aquarium Association is trying to keep their populations alive through a “species survival plan.”
The plan is a cooperative effort among zoos to increase genetic diversity and to guard against extinction through captive breeding.
Part of Schoeberl’s job is to log records on dragons in zoos across North America.
“It’s improved over the old way, where no one knew what anyone else was doing,” said Schoeberl. “It’s an evolving system.”
From the moment the dragons hatch or are captured in the wild, information goes into the studbook.
Armed with this record, the Komodo dragon management committee plugs the numbers into a computer program geared to maximize diversity.
The committee makes recommendations about which animals should mate. Then, participating zoos swap animals.
More than 100 captive species are covered by the survival plans.
Participating zoos agree to abide by the management committee’s recommendations. But matchmaking can be complex.
What looks like a good match on paper doesn’t always work.
“Clouded leopards are a prime example of a species that is just very difficult,” Schoeberl said.
When clouded leopards mate, they often use their large canine teeth to bite the neck of their partner, she said.
“Sometimes they bite right through the spinal cord,” Schoeberl said.
The committees learn from past mistakes, Schoeberl said. For example, animals nearing old age that hadn’t yet reproduced were once given priority for mating.
The fear was that those animals’ genes would be lost forever. But usually there’s a reason these older animals haven’t reproduced, she said.
“What happens is they probably have bad semen; they’re cranky and they don’t get along with others; they kill their mates,” Schoeberl said.
Castor and mate Odoe came from the National Zoo in Washington, D.C., in 1994 as part of the survival plan.
Odoe bore two sets of young, two in 2002 and five in 2003 before dying in 2004.
Castor and his offspring live in the zoo’s Tropical Discovery, where Dad is known to chase zookeepers out of his enclosure – even when they are bringing breakfast.
Staff writer Michelle Wallar can be reached at 303-820-1201 or mwallar@denverpost.com.
