WASHINGTON -- The National Zoo is celebrating the birth of a pair of Sumatran tiger cubs, a critically endangered species. There are only 500 Sumatran tigers both in captivity and in the wild, so these two additions are extra special.
The zoo announced Thursday that the cubs born to 4-year-old Damai on Monday appear to be healthy and the new mother has been seen grooming and nursing them.
This is Damai's first litter, sired by 12-year-old Kavi. Damai arrived at the zoo in 2011 from the San Diego Zoo and Kavi came a year ago from Zoo Atlanta.
The zoo confirmed Damai's pregnancy in June through an ultrasound after she gained weight and exhibited behaviors indicating she could be pregnant. Though they weren't sure how many cubs she'd be having. Her first ultrasound showed two spinal cords, but the second was different.
"The second ultrasound we saw one definitive clear heartbeat. So, we were hoping for two or more, but we were happy and thankful to just see indications of the one," says Dell Guglielmo, animal keeper at the National Zoo's Lion/Tiger department.
Mother and cubs are away from the public eye in what's called a cubbing den. Guglielmo says since tigers are solitary in the wild, not a pride species like lions, they try to mimic the den Damai would choose in the wild.
"So to be able to separate them, they are used to being solitary. That's ideal for her and we want to set her up to succeed as best we can," Guglielmo says.
This is Kavi's second litter. He has had more breeding experience and zookeepers were concerned about the two successfully mating.
"Luckily, he was a patient dad because introductions can be dangerous. They've had severe injuries if not worse introducing tigers together. If it doesn't work out, things can go wrong," Guglielmo says.
Damai is being remotely monitored to allow her to bond with her cubs who zookeepers describe as energetic. The cubs won't be exhibited until November, but fans can watch them on webcams.
WTOP's Megan Cloherty contributed to this report.
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