Southern resident orca population declines even further

By Jami Makan

Three adult orcas are missing and presumed dead, bringing the Southern Resident orca population down to 73.

According to a press release from the Center for Whale Research (CWR), the missing adult orcas are from the endangered Southern Resident killer whale population that historically frequents the Salish Sea almost daily in the summer months.

“Due to the scarcity of suitable Chinook salmon prey, this population of whales now rarely visits the core waters of its designated critical habitat: Puget Sound, Georgia Strait and the inland reach of the Strait of Juan de Fuca,” said CWR’s release.

Michael Weiss, a field biologist with CWR, said there are several reasons for the scarcity of suitable Chinook salmon prey. This includes historical overfishing, although he noted that fisheries management has slowly improved over time.

“The main issues now have to do with the lack of quality spawning habitats for Chinook salmon,” said Weiss. “They spawn in the rivers and the spawn come back out to the ocean. A lot of the issues have to do with spawning rivers being obstructed or degraded.”

Salmon spawning rivers along the west coast have been degraded in a number of ways. One major issue has been the clear-cutting of forests along streams where the salmon travel. “It’s removing a lot of shade that these young salmon need to keep cool,” said Weiss. “They will literally cook in the water.”

Other problems include pollution of the spawning rivers from pesticide runoff, as well as obstruction from inadequate culverts, or tunnels that carry streams under roads. Dams are another form of obstruction that make it harder for salmon to get up the rivers.

According to CWR, the Southern Resident killer whales, or orcas, are a large extended family or clan comprised of three pods, named J, K and L. Within each pod, families form into sub-pods centered around older females, usually grandmothers or great-grandmothers. Both male and female offspring remain in close association with their mothers for life.

CWR’s most recent data goes up to July 1. As of that date, the Southern Resident orca population totaled 73 whales – 22 in the J pod, 17 in the K pod and 34 in the L pod.

According to CWR, each pod is missing a whale. The missing whales are known as J17, K25 and L84.

J17 was a 42-year-old matriarch and mother of Tahlequah (J35), who carried her dead calf for an unprecedented 17 days last year. CWR reported that J17 was not in good body condition last winter, perhaps from stress. J17 is survived by two daughters and a son.

K25 was an adult male in the prime of his life who was not in good body condition last winter. He is survived by two sisters and a brother.

L84 was a 29-year-old male, who was missing all summer in encounters conducted by the Canadian Department of Fisheries and Oceans along the west coast of Vancouver Island. L pod has not come into the Salish Sea yet this summer, said CWR. L84 was the last of a matriline of 11 whales, 10 of whom died previously.

Weiss said he expects a further reduction in the number of Southern Resident orcas, which peaked at nearly 100 in the 1990s. “Until we get the salmon population back up to what they need to be, I think we’re going to continue seeing a decline,” he said. “But this isn’t a moment to panic, and they are not a lost cause. There is still time to take action that is meaningful.”

An example of meaningful action would be breaching the four dams on the lower Snake River, a topic that has been discussed for years. “We’ve done the work and we know what has to happen, and there seems to be this political bureaucracy that wants to continue studying and discussing it without taking any action,” said Weiss, who also called for greater funding of general habitat repair efforts in Washington state and B.C.

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