The previous two calves were born to the J pod, whereas this new orca was spotted within the L pod, by biologists with the U.S. National Oceanic and Atmospheric Administration off the coast of Washington state.
"We were about 15 miles west of Westport this morning when we re-sighted the whales and observed a new calf —L94 appears to be the mother," a statement from the NOAA says.
"The calf looked very energetic. We have five more days on the cruise and look forward to additional observations."
Though the births are considered encouraging, Dr. Lance Barrett-Lennard, head of the Vancouver Aquarium Cetacean Research Program, says this orca population remains under threat.
"At only 80 individuals, it still has a long road ahead of it on the way to recovery," she said in a statement.
The southern population spend their summers in the waters around southern Vancouver Island and northern Washington, but can travel much farther in the winter.