Missing killer whale's calf also feared dead

Another orca is missing off the coast of B.C.,a researcher on Vancouver Island says, bringing the number of killer whales feared dead to six.

Five adult orcas were reported missing and feared dead last week by the federal Department of Fisheries and Oceans.

One of the missing whales had a four-month-old calf, and now that baby is nowhere to be found, said Paul Spong, who runs the OrcaLab whale research station near Alert Bay on Vancouver Island.

Baby orcas can sometimessurvive without their mothers,Spong told CBC News, but that doesn't seem to have happened in this case.

"In some cases,the baby is able to hook up with another female who essentially takes over the role of the mom. It seems in this case unfortunately that hasn't happened."

Spong said it's likely that all six of the missingwhales are dead.

Researchers saythe B.C. whales could be going hungry because of fewer salmon, or could be getting poisoned by toxic chemicals.