World's oldest known killer whale Granny dies
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| CWR. J2, or Granny, in the Salish Sea in 2010 |
Estimated to be over 100 years old, the matriarch's official name was J2.
She was the focal point of a recent BBC documentary that followed biologists' study of her clan of orcas, an effort to unravel an evolutionary mystery.
Studying female orcas, which live long beyond their reproductive years, has revealed insights into the menopause.
Menopause mystery
Only three mammals are known to experience menopause - orcas, short-finned pilot whales and humans. Even our closest ape cousins, chimpanzees, do not go through it. Their fertility peters out with age and, in the wild, they seldom live beyond childbearing years.
Following Granny and other matriarch killer whales has shown their crucial role within the family group. They guide the pod as it forages, take care of other females' young calves and even feed the larger males.
These post-reproductive female leaders help their families to survive, and the advantage they offer could show what drives a species to evolve to stop reproducing.
This research continues, but an icon of the most well-studied killer whale population on the planet will no longer be part of it.
Prof Darren Croft from the University of Exeter, UK, who leads this evolutionary biology research, 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."
Orca census
The orcas of an area known as the Salish Sea - close to Vancouver and Seattle - have been the subject of a four decades long study led by Dr Ken Balcomb from the Center for Whale Research (CWR).
Dr Balcomb started this work after a period - between 1965 and 1975 - during which killer whales were taken from the Salish Sea to supply marine parks. The predictable habits of these Southern Resident killer whales, as they are called, made them an ideal target for capture,
By observing and cataloguing the killer whales since 1976, when he first photographed Granny, Dr Balcomb exposed just how unsustainable the hunting of the whales was. He and the CWR garnered the Southern Residents protection as an endangered species.
On the centre's website, which first reported Granny's death, Dr Balcomb wrote that he last saw her on 12 October, 2016, as she swam north far ahead of the others.
"Perhaps other dedicated whale-watchers have seen her since then," he wrote, "but by year's end she is officially missing from the Southern Resident Killer Whale population, and with regret we now consider her deceased."
Prof 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 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."
Starving whales
The population of Southern Residents is now estimated to be just 78 animals, as of 31 December 2016.
Numbers of salmon, which these killer whales feed on, are dwindling in the region. This has prompted Dr Balcomb to wonder if there is a future for these animals as their food supply runs down.
RIP 'Granny': World's oldest killer whale, who swam the oceans before the Titanic sank, dies at the age of 105
Born one year before the ill-fated Titanic struck an iceberg, the world's oldest known killer whale is believed to have died after going missing.
The killer whale, who was affectionately known as Granny, is estimated to have been 105-years-old at the time of death.
She was last spotted on 12 October in the Haro Strait - but scientists have now lost hope that they will ever see her again.
Researchers have studied the remarkable cetacean since 1971 when they estimated she was 60 years old and gave her the official name of J2.
Her presence stunned scientists because killer whales, or orcas, typically live to between the age of 60 and 80 in the wild.
Dr Darren Croft from the University of Exeter, who leads this evolutionary biology research, told BBC News: 'It was inevitable that this day was going to come but it is very sad news.'
Granny was a matriarch of a group called the Southern Resident Killer Whales in the Pacific Ocean.
Experts from Ocean EcoVentures Whale Watching were previously able to identify her thanks to a marking on her dorsal fin, as well as as a half-moon-shaped notch.
In 2014, Granny was spotted in the Strait of Georgia, when she was thought to have travelled up from California with her pod.
Her return to the area in July was the first time in years was announced by the Pacific Whale Watch Association (PWWA)
The average lifespan of a wild orca is between 60 and 80 years, but other members of the Southern Residents have lived almost equally as long lives as Granny, including females Ocean Sun and Lummi, who died aged 85 and 98 respectively.
Other Southern Resident orcas including Tokitae, who lives in Miami Seaquarium, and Northern Resident orca Corky in SeaWorld San Diego, are both the oldest killer whales in captivity, aged around 52 years old.
The earliest photo of Granny was taken in 1967 and while experts began to study her pod in 1971, Dr Ken Balcomb, one of the leading orca experts in the world, began studying the Southern Resident Killer Whales in 1976.
Dr Balcomb wrote that he last saw her on 12 October, 2016, as she swam north far ahead of the others.
'Perhaps other dedicated whale-watchers have seen her since then,' he wrote.
'But by year's end she is officially missing from the Southern Resident Killer Whale population, and with regret we now consider her deceased.'
When he first began documenting Granny and her familiy in that year, he saw that the mature female was almost always travelling with a mature bull.
'This mature bull was know as J1 or 'Ruffles' due to the waves in the trailing edge of his dorsal fin,' Mr Pidcock explained.
Because offspring stay with their mothers for life, Ruffles was thought to be Granny's only living offspring in the pod.
Sadly, he died in 2010 at approximately 60 years old.
Granny, the world’s oldest killer whale is missing presumed dead
he world’s oldest killer whale, who was born a year before the Titanic sank, has not been seen in her pod since October, leading to fears that she has died.
The female orca, affectionately known as ‘Granny’ by scientists studying her, was the oldest of a group of whales that researchers have been following for the past four decades.
The family of killer whales lives in an area known as the Salish Sea - close to Vancouver and Seattle - and Granny was first observed and photographed by Dr Ken Balcomb of the Centre for Whale Research since 1976.
Dr Balcomb said he last saw the whale on 12 October, 2016, when she swam north far ahead of the others. It was thought she could be as old as 105, meaning she was born in 1911, a year before the Titanic sank.
"Perhaps other dedicated whale-watchers have seen her since then," he said.
"But by year's end she is officially missing from the Southern Resident Killer Whale population, and with regret we now consider her deceased."
Recently British scientists have been following Granny’s pod to study whale menopause. Only humans, orca and short-finned pilot whales go through the menopause in the entire animal kingdom, and scientists were hoping to find out why.
Granny, whose official name was J2, was one such post-reproductive leader, who help care for young and pass on knowledge of good feeding grounds to young members.
Prof Darren Croft from the University of Exeter who leads this evolutionary biology research, 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.
Prof Croft said that it was "just incredible" to think of what Granny lived through.
"She lived through the live captures and in recent years her world has changed dramatically with dwindling salmon stocks and increases in shipping threatening the survival of this incredible population,” he said.
"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."
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