Two male polar bear cubs, born last November at Hogle Zoo, are doing well but will not go on display until spring, at a coming-out party possibly in early April.
"It depends on how the bears are progressing. They're now so small (that to put them on public display) would pose some hazards. The moat as well as the pool (in the polar bear exhibit) would cause" potential harm for the cubs, said zoo spokesman Andrew Wallace.The cubs, which were born to Chinook the evening of Nov. 18 or the morning of Nov. 19, each weighed an estimated half-pound to one pound at birth. Last week they weighed 16 and 17 pounds.
Delaying the time for their display is a preventive measure, giving the animals time to increase in size. Officials hope the cubs will weigh 40 pounds by the time they are placed on exhibit.
"They're still in the baby stage and getting their feet underneath them, similar to being in a playpen. It's a secured area to where (zoo officials) don't have to worry about the hazards associated with a public exhibit," Wallace said.
He said 20-year-old Chinook, who came to Hogle Zoo from a Memphis, Tenn., zoo, is a very good mother. Removing the cubs from her constant, watchful care would cause stress for the mother, Wallace said.
It's unusual for a polar bear, he said, to raise her cubs to maturity. Often the mother eats her young. And a father polar bear will sometimes eat his offspring if given the opportunity, particularly in the wild, Wallace said.
Andy, the father of the cubs, is a 6-year-old male who was brought to the Utah zoo in 1995 from the Buffalo, N.Y., Zoo. Andy is being kept away from the mother and cubs because he could pose a threat to the baby bears. Andy replaced Bubba, who died of pancreatitis in 1993.
"In most cases when we are loaned a male or other partner in a breeding agreement, we typically give the loaning institution one of the cubs," Wallace said. The Buffalo zoo may receive one of the new cubs.
He said some polar bear mothers reject their newborn, as illustrated in the birth of two cubs a couple of years ago at the Denver Zoo. That zoo placed the cubs on display at an earlier time because of the mother's rejection. The cubs had to be hand raised by zoo staff.
The new Hogle Zoo cubs were seen by zookeepers for the first time early on Nov. 19, with the use of a surveillance video camera installed in the top of Chinook's cave. Chinook entered the cave around the first part of the month and went into a state of semi-hibernation. She has lived solely on her own body fat and has provided milk for her nursing cubs.
Wallace said the video camera was set up in preparation for Chinook giving birth. Zookeepers wanted to monitor the mother's condition. Polar bears are secretive when they're about to give birth. Without the video camera, zoo workers would not have been able to monitor Chinook's progress.
As is the case with other polar bear cubs born at Hogle Zoo, the pair will be kept at the zoo until about age 2, when they will be sold to another institution. Denali, Chinook's last cub who was born in 1993, was shipped to a zoo in Japan.