Prince William's work protecting wildlife rangers is more than a passion project - analysis by Cameron Walker

Last week, I attended a secret screening to watch the first three episodes, and the Prince unexpectedly joined us.

The future King gave an enthusiastic introduction and then took part in a Q&A session alongside wildlife presenter Michaela Strachan.

None of it was scripted; he appeared to be speaking from the heart and had a deep knowledge of the subject.

I understand the Prince was heavily involved in both the pre-production of the series and the edit process, but did not have an official "executive producer" role.

Royal sources tell me, however, that the docuseries was his idea - his "brainchild". Prince William told us: "I've been dying to do something around this sort of space for a while."

He continued: "The feedback I'm getting from [rangers I have met] is just how much more dangerous the job has become.

"I don't think that's because it's more reported. That's obviously something we discussed. I think it's actually because it's becoming more real, and unfortunately, the permutations of local areas and all the community conflicts or civil wars or illegal fishing or poaching, whatever it might be, are just spreading further and further across the globe.

"At some point, we have to say enough is enough and highlight all the bravery that these men and women do on a daily basis to protect the natural world."

The Prince of Wales claims being a wildlife ranger is "one of the most dangerous jobs on the planet" - on par with soldiers and emergency services.

1,400 rangers have been killed in the last 10 years, and the Prince was keen to emphasise the lack of incentive for people to become rangers nowadays, citing poor pay, lack of equipment, and dangerous conditions.

Leading conservationists estimate 1.5 million more rangers are needed to reach the 2030 target of protecting 30 per cent of the world's land and sea.

I was with Prince William in Cape Town last November, when he announced a brand new support package at the United for Wildlife Global Summit.

10,000 rangers will have access to affordable medical evacuation insurance and opportunities for training and leadership development.

For the families of loved ones tragically killed in the line of duty, they now have access to life insurance coverage, ensuring the bereaved are not left without any income.

As great as this is for the individuals benefiting, the support package only goes so far; Prince William's impassioned pleas are unlikely to go much further by themselves.

It is up to Governments, the private sector and local communities to fund and support the 1.5 million extra rangers needed to protect nature.

The Prince of Wales has deep pockets, but certainly not big enough to fund all this by himself. He is also above politics and cannot force Governments to take action.

What he can do, however, is use his convening power to bring key players around the table to come up with solutions. The main aim of the docuseries is arguably an early step in his long-term mission - raising as much awareness as possible about the plight of rangers around the world.

Choosing a digital-first platform (BBC Earth YouTube has a global audience of 13 million subscribers), as producers have done, could also be more effective than a domestic linear audience in the 21st century.

Let's see if Guardians gains the public profile needed to spark the change Prince William wants to see. The series premieres across all of BBC Earth's channels on Friday, May 23, with a new episode landing weekly. Episodes will also be screened at Adventure Cinema locations across the UK.