Researchers say a fourth baby has been born to an endangered population of killer whales found off the British Columbia coast.
Researchers and whale watchers spotted the newborn Monday in Active Pass off Galiano Island, a Gulf Island between Vancouver Island and the mainland.
Michael Harris, executive director for the Pacific Whale Watch Association, said catching a glimpse of yet another baby was a wonderful surprise.
"We were just basking in the glow of having three babies and then we just found this other one."
Scientists say it's the fourth calf to be born among the southern residents this season, with three calves in J pod and another in L Pod.
The southern resident population is made up of three pods — J, K and L — and the latest birth brings the total population to 81 for the rare orcas.
Brad Hanson, a wildlife biologist with Fisheries department of the National Oceanic and Atmospheric Administration in Seattle, said the baby is believed to be just days old.
One of the telltale signs of its age were heavy creases, or fetal folds, on the animal, which are developed in the womb and take a few days to fill out, he said.
Hanson said the new calf's mother still hasn't been identified because the baby was seen with a female that had already had a calf.
Researchers went from depression a few months ago about the potential for the endangered population to optimism after the new additions, Hanson said.
In December, the body of a pregnant female from J pod washed up on a Vancouver Island beach.
"Seeing that much reproductive potential vanish in the population was very distressing. This is encouraging, though obviously the calves have to survive."
Only about half of killer whale calves born in the wild survive the first six months of life.
Although Hanson said all the animals appear to be active and robust he's hopeful the odds for them are better.
The three pods — which are listed as endangered in the United States and as a species at risk in Canada — haven't had a surviving calf for three years.
Researchers can't explain the baby boom, but Hanson said they're very interested in who the father or fathers might be. Earlier studies suggested most of the breeding was done by the biggest, oldest male, but that animal died a few years ago.
For the long term, Hanson said researchers hope all the calves are female because there are only about 30 females in all three pods.
While the whales are one of the best-studied cetaceans in the world, Hanson said researches still have much more to learn about how to help the population rebound.
"It is a little bit frustrating. When we started into this a dozen years ago we were hoping for maybe some easy answers. I guess that's just part of the natural world as it's not necessarily a simple situation."
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