Updated: March 1, 2014 at 1:30 pm
PITTSBURGH (AP) — Pittsburgh's lone male polar bear is working to make his species a little less threatened.
That is, if six straight months of mating with three female polar bears can be considered work.
"What Koda is doing is very important for the future of polar bears," said Dwayne Biggs, curator of aquatic life at Pittsburgh Zoo & PPG Aquarium.
Koda, 9, is expected to spend the first half of the year mating with his exhibit mate in Pittsburgh, Kobe, 13, and two 18-year-old bears flown in from SeaWorld San Diego, Szenja and Snowflake.
Szenja also came to Pittsburgh last year. Szenja and Kobe each showed signs of pregnancy during the fall, including weight gain and denning behavior, but they turned out not to be pregnant. Such "false positives" are common in polar bears.
If breeding is successful this year, the resulting cubs could become attractive promotional tools that draw more visitors to the Pittsburgh and San Diego facilities. Although that could provide a boost for their bottom lines, officials see a bigger opportunity.
"It gives us an opportunity to talk about the threats that polar bears are facing in the wild," said Maria Franke, curator of mammals at Toronto Zoo.
Toronto is home to North America's youngest polar bear in captivity. The cub, born Nov. 9, quickly became a celebrity. A YouTube video of the cub's first steps has been watched more than 6 million times since being posted on Jan. 8. Its photo — along with the message "You can visit our cub!" — is on the home page of the zoo's website.
"There were lines to come see him," Franke said of events held Thursday in conjunction with International Polar Bear Day.
The Pittsburgh zoo's International Polar Bear Day event is Saturday from 11 a.m. to 3 p.m.
Eric Otjen, assistant curator of mammals at SeaWorld San Diego, said the California facility will spend "in the six figures" to send its two polar bears to Pittsburgh for the breeding season. The costs include shipping the bears back and forth via FedEx. The move forced SeaWorld San Diego to close its polar bear exhibit until Szenja and Snowflake return.
"We feel the commitment is well worth it. This isn't just a way for SeaWorld or the Pittsburgh Zoo to get more bears. It's about learning how polar bears breed and how we can take what we learn from captive polar bears and apply it to real-world situations," Otjen said.
Biggs said Koda, 9, is one of 13 male polar bears in captivity across the United States that is considered a good candidate to produce offspring. Another is Koda's twin brother Nuka, who lived in Pittsburgh before moving to Detroit several years ago.
Biggs said 15 females in captivity are deemed "breedable," including the three in Pittsburgh.
This is Koda's third breeding season. Biggs said the 900-pound bear "is not proven yet, but he's acting more confident every day."