Prince William Secretly Helps the Families of Murdered African Park Rangers

Oxford Films/Neil Harvey/Discovery+ Prince William

Prince William is helping the families of African park rangers killed in the line of duty.

The Duke of Cambridge, 38, has made a secret donation to the Thin Green Line Foundation, which provides lifeline grants to families of the estimated 150 conservation rangers murdered while protecting wildlife each year.

The donation — described by a Kensington Palace spokesperson as "a private matter" — was made in direct response to the killing of six rangers at the 3,000-square-mile Virunga National Park in the Democratic Republic of Congo on Jan. 10.

"We are very grateful to The Duke of Cambridge for his recent support through our Fallen Ranger Fund for the families impacted by the devastating loss of six Rangers at Virunga National Park in January," The Thin Green Line Foundation tweeted on Friday.

We are very grateful to The Duke of Cambridge for his recent support through our Fallen Ranger Fund for the families impacted by the devastating loss of six Rangers at Virunga National Park in January.

For information and to donate please visit: https://t.co/YtexDdZGWY

— The Thin Green Line Foundation (@ThinGreenLine_) February 19, 2021

William publicly spoke out about the "horrendous attack" at the UNESCO World Heritage Site in January, via a Kensington Palace release.

"I condemn the actions of those responsible in the strongest terms," he stated. "Rangers who work tirelessly to protect both the national park and the neighboring communities should be honored not attacked. They should never find themselves in a position where their lives are on the line."

The plight of Africa's frontline conservation rangers is extremely close to the heart of William, who is president of the anti-poaching initiative United for Wildlife, which he spearheaded in 2014 to fight the $50-150 billion illegal wildlife trade.

Oxford Films/Tim Cragg/Discovery+ Prince William

In January 2019, the Duke also launched the multimillion-dollar Earthshot Prize to champion new ways of addressing the twin challenges of climate change and conservation. The Prize aims to award its first raft of five, $1.3 million grants at the end of 2021.

"I felt very much that there's a lot of people wanting to do many good things for the environment and what they need is a bit of a catalyst, a bit of hope, a bit of positivity," William said in an October interview alongside iconic naturalist Sir David Attenborough.

"I think that urgency with optimism really creates action."

Kensington Palace Sir David Attenborough and Prince William

The Thin Green Line is supported by the equally iconic naturalist Dr. Jane Goodall. Speaking exclusively to PEOPLE in July to celebrate the 60th anniversary of her groundbreaking research on wild chimpanzees in Tanzania, Goodall described how the security of working in what is now Gombe Stream National Park revolutionized how we think of chimpanzees — and ourselves.

She also opened up about her friendship with William's brother, Prince Harry, who is president of the NGO African Parks and previously called the continent his "second home."

Kirsty Wigglesworth/AP/Shutterstock Prince Harry and Dr. Jane Goodall

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"Prince Harry is great. Really great," she told PEOPLE. "And Meghan too."

Harry also famously invited Goodall for an impromptu dance — and reenacted a sweet "Chimpanzee Greeting" she taught him – at the 2019, Global Leadership Meeting for the Jane Goodall Institute's Roots & Shoots youth program at Windsor Castle.

"She is a woman of kindness, warmth, immense knowledge, and a softness that's needed by mankind just as much as it is chimpkind," Harry told the group that day. "I've been admiring her work since I was a kid, and it was so wonderful to find that she was even more amazing in person."