2016 took far too many lives, and one of them was Granny, the world's oldest known orca.

J2, known as Granny, had been spotted thousands of times over 40 years of orca surveys but has not been seen since October, according to the Center for Whale Research on San Juan Island, a nonprofit group that keeps the federal government’s annual census of the whales, and is assumed to have passed, bringing the toll of dead or missing whales to seven in 2016, the researchers say.

Center for Whale Research

“With regret we now consider her deceased,” researcher Ken Balcomb wrote in a post on the center’s website Saturday.

She was typically seen at the head of the J pod, one of three family groups of whales that travel with their mothers or grandmothers. Other members of her family have been photographed and counted.

The Seattle Times reports that "despite a decade of research, protection and recovery efforts, the orcas continue to struggle primarily due to a lack of food, pollution and disturbances by marine vessels."

Center for Whale Research

The whales were listed as endangered in 2005. While there were more than 140 animals decades ago, that number declined to a low of 71 in the 1970s when dozens of the mammals were captured to be displayed at marine parks and aquariums across the nation. The numbers have fluctuated in recent years, and are currently said to be at just 78.

Professor Darren Croft from the U.K.'s University of Exeter, told BBC News: "It was inevitable that this day was going to come but it is very sad news and a further blow to this population."

He explained that in her later years she had "been helping her family group to survive by sharing her knowledge of when and where to find food."

Croft added that it was 'just incredible' to think of what Granny lived through over the last century and how the world and her environment had changed over that time - she is believed to have been born a year before the Titanic sank in 1912.

Center for Whale Research

"She lived through the live captures," he told BBC News, "and in recent years her world has changed dramatically with dwindling salmon stocks and increases in shipping threatening the survival of this incredible population.

"Although J2 is gone we will continue to benefit for many decades to come, from the incredible data collected on her life over the last 40 years by the Center for Whale Research."

You can view more images and read more about Granny and the southern resident whale community at the Center for Whale Research.

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