There's the distinguishing cut in her fin, all that acrobatic breaching, and the fact that she was always out front, cruising through the Pacific Northwest and slapping her tail whenever other whales went astray. There was just no mistaking Granny.

The southern resident killer whale believed to be the world's oldest known orca was already an adult in Washington State's Puget Sound in the late 1960s when these creatures were corralled and captured for marine aquariums around the world. Even then she was likely postmenopausal and was considered too old to be shipped off and sold to some park. So wranglers let her keep swimming in the wild.

The always lively whale went on living another five decades after that, until finally disappearing sometime last fall. J2, the orca known as Granny, has not been seen since October and is now considered likely dead.

That brings that endangered population of killer whales down to 78 from a likely high in the 1800s of 200 or more.

"She was exuberant. She was fun to watch," said Deborah Giles with the Center for Whale Research. "It's a heartbreaking thing for many of us."

How Old Was She?

No one really knew Granny's age. In the 1970s, when scientists were first discovering that they could use markings to distinguish killer whales from each other, J2 already was without calves. Scientists at the time presumed she was at least 40.

A paper published in 1987 suggested she was likely born in 1911, making her an astounding 105 years old. A recent biopsy of J2 that analyzed fatty acids and other chemicals suggested her age range more likely fell between the mid-60s and early 80s.

"We're still stumped as to why males don't seem to survive as long," said Brad Hanson, a killer whale expert with the National Oceanic and Atmospheric Administration. "We know that the median age of male survivorship is 10 years less. But why is that?"

And it's not that killer whales (which technically are dolphins) live longer than other cetacean species. Inupiat hunters in Arctic Alaska have found stone harpoons inside the blubber of bowhead whales that date to the 19th century.

But for an orca, Granny lived remarkably long and had managed over the past half century to become one of the most recognized killer whales in the world.

Famous Animal

For starters, Granny was commanding. The resident killer whales that occupy the waters of Puget Sound and the Strait of Georgia form the J, K, and L pods, and Granny was always the one out in front of J pod.

"I have notes from my own fieldwork in 2007 and 2008 where I'd watch her get to these junctions where whales could either go left or right," Giles says. "Some whales would head one way, and she'd go another and eventually stop and pound her tail on the water. They'd turn around and come back to her."

Among killer whales, matriarchs help determine where the rest of the pod should travel and eat, seeking out the richest sources of Chinook salmon even as the numbers of fish dwindle.

"She was the counselor, the guide, the teacher of traditions," said Howard Garrett of the Orca Network.

She also had such peerless strength that even within a few months of her last sighting she was known to regularly vault completely out of the water. One scientist called her "the Energizer Bunny of whales."

And she was for years so associated with J1, a well-known old male known as Ruffles who died in 2010, that many believed she was J1's mother. Research published in 2011 suggests that was not the case, but Granny was also known to pick up stray males, helping care for them when their own mothers died. A young orphaned male from a neighboring family, L87, had been following Granny around of late, leaving scientists now to worry about his fate, too.

"He was almost always stuck like glue to J2," Giles said. "The stats and studies show that males are eight times more likely to die within a year of their own mothers dying, so we're concerned."

In fact, that, ultimately, is how the Center for Whale Research—which keeps a census of southern resident killer whales for the federal government—ultimately determined J2 was probably dead.

"At this time of year, the whales are really spread out and the swells are big, so it's easy to miss them," Giles said. "Our policy is that we want to have three encounters with the pod before we determine that an animal is gone."

By late December J pod had been seen several times. And L87 was always traveling without Granny by his side.