The newest calf born to the endangered southern resident killer whales is presumed dead, researchers say.
J60, a young male born in late December, was not seen during an encounter with all members of J Pod near the San Juan Islands on Saturday, according to the Center for Whale Research based in Friday Harbor, Washington.
Researchers used telephoto lenses and a permitted drone to document the 25-member pod of salmon-eating orcas in the San Juan Channel for nearly two hours, but the little one wasn’t there.
Researchers said photos of both potential mothers — J42 and J46 — showed they were not with the calf. While the Center for Whale Research usually does three full surveys of the group to confirm mortality, it believes J60 is “likely deceased.
“Given his young age, it is extremely unlikely that J60 was off on his own during the entire duration of the encounter,” the group said in an Instagram post.
Scientists were not entirely sure which orca gave birth to J60. Both J42 and J46 were pregnant late last year and the calf spent time with both females. It would have been the first observed calf for either orca, the centre said.
“Given the calf’s association patterns and the pregnancy status of J Pod females in late 2023, J42 was the calf’s most likely mother,” said the centre. “However, given the calf’s varied social partners in early life this will enter our data set as a ‘probable’ relationship.”
Researchers said J46, was “not as consistently associated with the calf as J42.”
The Center for Whale Research said the mortality rate for young calves, especially those born to first-time mothers, is very high among the southern residents. “This is due both to the generally poor nutritional status of southern residents and the transfer of toxins from mother to calf during gestation and lactation,” said the centre. “The southern residents need abundant, large chinook salmon if they are going to be able to raise their calves to maturity and keep the population going.”
The latest population survey of the southern residents, conducted last July, listed the total number as 75 animals in three pods. L-Pod had 34 orcas, J-Pod 25 and K pod 16.
