The sick orca scientists have been trying to save is presumed dead.

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The Center for Whale Research delivered the message on Thursday afternoon. The last known sighting of J50, also known as Scarlet, was on Friday, Sept. 7. Scientists have spotted other members of her pod since then.

The death is a major blow for the Southern Resident killer whales.

“The message brought by J50, and by J35 and her dead calf a few weeks ago, is that the SRKW are running out of reproductive capacity and extinction of this population is looming, while the humans convene task forces and conference calls that result in nothing, or worse than nothing, diverting attention and resources from solving the underlying ecological problems that will ultimately make this once-productive region unlivable for all.”

– Ken Balcomb, Center for Whale Research

NOAA, however, is not ready to give up their rescue response and will continue looking for the 3-year-old orca to make sure she’s not stranded.

They’re asking all boaters and pilots around the San Juan Islands to keep watch until further notice.

If NOAA finds Scarlet, they’ll likely try to capture her and perform a physical examination with the hope that new treatments might save her life.

NOAA Fisheries released this statement about the orca:

Unfortunately, J50 has not been seen in several days of favorable conditions and sightings of her pod and family group, including J16, her mother. Teams were on the water searching yesterday and are increasing a broad transboundary search today with our on-water partners and counterparts in Canada. We have alerted the West Coast Marine Mammal Stranding Network, which is a tremendous resource in such situations. Airlines flying in and out of the San Juan Islands are also on the lookout. We greatly appreciate all the help and concern.

“She was very emaciated; she was showing signs of what we call ‘peanut head,'” Balcomb said. “We’ve never seen a whale recover from that condition.”

“J Pod has been around the area for a number of days, probably four or five days,” Balcomb said. “The family of J50, J16 is also there. But nobody has seen (J50).”

Federal wildlife experts have been planning to capture the sick orca, then treat her medically. That action is considered a “last resort.” Orca have strong family bonds and researchers have not wanted to disrupt the unit.

Researchers believed that J50 was suffering from worms. Scientists have been trailing the sick whale for weeks, gathering samples to determine her condition. They even attempted to feed her salmon dosed with medicine and shot a dart at her with antibiotics.

There has been great interest in the health of the pod and J50 because the Puget Sound area’s orca population has been suffering. J50 is a female and it was hoped she would recover.

“Because she’s an important part of the population,” said Lynne Barre, NOAA Fisheries Marine Mammal Authorization Program. “A young female has the potential to be a functioning part of her family and contribute to the recovery of the population.”