Orca numbers up

A year after researchers feared a drop in the American Northwest's endangered killer whale population meant disaster, the number of orcas has bounced back with six new babies and no whales lost.

Though scientific evidence is skimpy, some whale experts say the good news might be the result of enough salmon for orcas to eat. Others say so little is known about orcas that the baby boom could be because of any number of factors, or simply a statistical fluke.