Cocaine gangs used to have this land on lockdown – but the new war in the vanishing Amazon is all too clear to see
Former Science Editor
From the air you can see why they call Chiribiquete National Park the jewel in the crown of Colombia's Amazon rainforest.
Giant columns of rock break through the tree canopy.
Tremendous waterfalls spill off the table-top mountains, or "tepuis", each with their own unique microclimates, plants and animals.
The park is nearly 17,000 square miles, the largest piece of protected rainforest in the world.
It was created to preserve the way of life for indigenous tribes living within it, and the unique wildlife with which they share the forest.
But it also serves as a giant barrier against the encroaching deforestation that threatens the Amazon rainforest from all sides.
But the barrier is in danger of crumbling.
Deforestation is encroaching.
The Amazon stores 20% of the carbon on Earth.
Water, trillions of tonnes of it, evaporating from its trees every year cools the atmosphere.
But a fifth of the Amazon has already been lost and thousands of square miles are still being cleared each year.
At some point, and climate scientists are unsure when, the Amazon could stop functioning as a sink for carbon and start becoming a source, as deforested areas start releasing more carbon than they store.
It's a climate change tipping point that we get closer to with each tree that is felled, and the planet continues to warm.
And as if that wasn’t enough, the animals and plants of the rainforest - which make up the greatest biodiversity on the planet - are disappearing.
Monday sees the publication of a new report by conservation charity WWF which has assessed the status of animals living in tropical forests around the world.
It finds populations of forest vertebrates - that’s mammals, birds, reptiles and amphibians - have declined by more than 50% since 1970.
And since then deforestation has only been accelerating.
The civil war protected much of Colombia’s rainforest - it was simply too dangerous for anyone to access the region - unless they were involved in the cocaine trade.
But since the 2016 peace agreement, for the first time in more than 40 years, the forest became up for grabs.
The peace has led to a new war on trees.
The people doing the logging have close ties to organised crime and remnants of the guerrilla group FARC, which refused to sign the peace agreement.
The deforestation frontline is around the town Calamar.
It’s too dangerous to visit independently.
We accompanied WWF-UK, which has been working closely with Colombian colleagues to protect the Chiribiquete National Park.
From the helicopter we filmed an illegally logged area just metres from the border of the national park.
The fringes of Chiribiquete have become some of the most rapidly deforested parts of the Amazon.
It’s a seemingly impossible challenge.
But one that some of the bravest local people have decided is worth taking on.
Maricela Silva is working with WWF to help organise teams of ‘Forest Explorers’.
They’re being trained in mapping techniques and are surveying the forest that surrounds their communities.
She used to work growing coca — the raw ingredient for cocaine.
But now, she tells me, she wants to protect the forest for her children and grandchildren.
And it’s not like humans can’t live in harmony with the rainforest.
The few expeditions there have been deep into the Chiribiquete National Park have been discovering some of its iconic rock faces decorated with pictograms some 20,000 years old or more.
They show the animal deities of the tribes which still inhabit the park - like jaguars, capybaras and anacondas - but also show small patches of farmland used to grow staple crops for humans.
The Colombian government says it is committed to protecting the Chiribiquete National Park and there are signs deforestation could be slowing in some parts of the country.
However globally, the pressure on tropical forests, for timber and farmland, is only increasing.
To ensure a comfortable climate for humanity, and a home for some of the most incredible wildlife on Earth, tropical forests can’t continue to disappear.
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