Farewell Duchess: The country's oldest Bornean orangutan dies aged 52 after cancer battle

North America's oldest Bornean orangutan has died at Phoenix Zoo aged 52, after a weeks-long battle with an aggressive form of cancer.

Duchess, a popular primate considered the matriarch of the zoo since its opening in 1962, was euthanized on Sunday after her condition worsened. She had been suffering from lymphatic cancer.

'The cancer was incredibly aggressive and over the past few days, Duchess became increasingly weak and more lethargic,' Gary West, executive vice president of animal health, said in a statement.

'The veterinary staff, alongside the keepers, made the difficult decision to humanely euthanize her.'

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Loss: Duchess, the oldest Bornean orangutan in captivity in North America, has died aged 52

Duchess had been diagnosed with the cancer two weeks ago after zoo officials noticed she had a loss of appetite and lethargy. An ultrasound test revealed the cancer.



West said efforts were made to make Duchess 'as comfortable as possible' in her final days. She could be seen peeking from underneath her blanket in her enclosure, too weak to get up.

Duchess was born in the Borneo jungle, where she was orphaned at a young age. She arrived at the Phoenix Zoo when she was two, and was one of the park's first animals when it opened in 1962.



In the zoo's early days, she would tour local businesses as part of fundraisers and became comfortable with human contact, officials said.

Beloved: Duchess, pictured in 2010, was one of the zoo's first animals when it opened in 1962

Battle: She was diagnosed with lymphatic cancer two weeks ago and was euthanised on Sunday morning

A mainstay of the zoo and one of its most popular attractions, Duchess was feted with an all-day celebration in March 2010, marking her 50th birthday.

She was given a frozen treat with her favourite fruit inside, a giant birthday card signed by zoo-goers and a 'Happy Birthday' song from visitors.

It kicked off a fundraising campaign for a $4 million orangutan exhibit, which opened in April 2011.

In her life, Duchess gave birth to seven offspring who are now at zoos across the country. She outlived four of her children.



She leaves behind a daughter, Bess, a granddaughter, Kasih, and the lone male, Michael, at Phoenix Zoo. Among her other offspring across the country, she leaves behind a great grandchild.

Favourite: Duchess (pictured) joined the zoo after she was orphaned at a young age. When the zoo first opened, animals would visit local businesses, pictured, to raise funds

Officials at the zoo mourned the passing of Duchess, but noted that it is common for orangutans to live 30 years in the wild and an estimated 40 years in captivity.

'Although we are deeply saddened by Duchess's passing, she long surpassed the number of years that orangutans live in zoos and preserves, as well as in the wild,' the zoo's president, Bert Castro, said in a statement.

Keepers at the zoo became emotional as they talked about their relationship with Duchess.

'I spend more time in a day, in a week, in a month than I do any human in my life,' senior keeper Bob Keesecker told News 12 .



Matriarch: Duchess, who had seven children, lived 22 years longer than the average orangutan in the wild

Intelligent: As zoo-goers flocked to the park's social networking sites, they noted that they often thought Duchess had been observing them, rather than the other way around



'What I remember really is my relationship with her. Everyone that works at the zoo pretty much knows I had a special relationship with her.

'She's the first person I check when I come in every day, she's the last one I check when I leave every day. I like to think she's enhanced my life even more than I did hers.'

Senior keeper Denise Wagner added: ' I take solace in the fact that she's 52, she's not 25. So she's lived a long life, she's live way past the median age .'

Fans flocked to the zoo's Facebook page to pass on their condolences and memories.

'I've been taking my students to observe primates at the zoo for 5 years,' wrote Lisa Marsio, a teacher from Scottsdale.



Family: At Phoenix Zoo, she leaves behind male Michael, granddaughter Kasih and daughter Bess

Home: Duchess lived in a $4 million orangutan enclosure, which opened in 2011 at Phoenix Zoo

'Duchess was always there, often gazing patiently at us as if she was the one doing the observing. Such great intelligence behind those eyes. She will be greatly missed.'

Zoo president Bert Castro added in a statement: 'We have been grateful for the outpouring of memories and stories about Duchess through our social media outlets over the past week.

'It has been a joy to see all of the lives she has touched throughout our community and beyond. She will be deeply missed.'

A celebration to honour Duchess will be held on Saturday between 7 a.m. and 2 p.m. at the zoo.

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