The oldest known orca is considered dead, according to The Center for Whale Research.

In the summer of 2016, whale researchers considered “J2 Granny” of the Southern Resident Killer Whale (SRKW) group J pod to be in high spirits after she was spotted near San Juan Island, but by the end of the year she was missing from the population.

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“Perhaps other dedicated whale-watchers have seen her … but by year’s end she is officially missing from the SRKW population, and with regret we now consider her deceased,” wrote The Center for Whale Research Executive Director Kenneth C. Balcomb. “We have now seen J2 thousands of times in the past forty years, and in recent years she has been in the lead of J pod virtually every time that she has been seen by anyone.”

The SRKW population is now estimated to be 78 as of Dec. 31, 2016, and J pod contains only 24 individuals plus the wandering L87.

The Orca Network reported last year that Granny was said to be around 105 years old, but there is a 12-year margin around her age, meaning she could have been as young as 90.

The average lifespan of a wild orca is between 60 and 80 years.

The Southern Residents -- despite being listed under the U.S. Endangered Species Act -- have some extraordinary longevity stories, including the female K7, or Lummi, who died in 2008 at the age of 98, according to the Pacific Whale Watch Association (PWWA).

Another Southern Resident female, L25, or Ocean Sun, is thought to be 85 years old.

According to Pacific Whale Watch Association:

“Wild orca researchers use an extrapolation scheme to estimate ages of orcas. It’s a well-accepted technique used by both U.S. and Canadian scientists, based on the fact that offspring stay close to their mothers all their lives.”