Chayan, a Huitoto guide, with the day's catch in Parque Nacional Chiribiquete.

Strangely, the noxious swarm of mosquitos intent on doing me harm had ebbed, and the growl of the Chiribiquete waterfall (below) no longer sounded, as if its familiarity to my ears after a few hours had dulled the incessant tumble of water. The sky opened, revealing an unforgettable jungle panorama here in the department of Caquetá.

By the looks of things, a hard rain was coming our way. Off in the distance lightning flashed menacingly. I looked back at where I had slung my hammock. Even beneath the thick-set foliage, there was no way I was going to remain dry after an Amazonian downpour. I felt envious of my expedition companions and their compact tents; I had neither a bivouac nor a large-enough waterproof. Rather than fret, I just secured my camera.

Butterflies at Chiribiquete waterfall.

For what it was worth, only one day previous I had been christened "Rambo" by our guides, and now their hammocks were strung up in an arc about my campsite. They knew best and I was amongst them.

Last night I was ridiculing German, another of our expedition group, for pitching his tent on the river’s beach – putting himself in favored boa hunting territory. Upon learning this, I had sought out the highest, smoothest flat-topped boulder I could find on which to settle down for the night. Surely the boas would get German first, and then perhaps other members of the expedition, before they got to me.

The misnomer "Rambo" came about when halfway through the first day of our three-day river trip, our guides Adán and Chayan spotted a family of floating peccaries that had come out the losers in a battle with the nearby rapids of Gapitana. Adán, with a few deft and expert swipes of his razor-edged machete – his skill turning all of us seasoned expeditioneers green with envy – had the hog’s entrails out on the rock and ready to use as fishing bait. The rest was for our consumption.

Chayan, Ibrahim and Pedro carved hunks of meat while we looked on, a little concerned. Finally, once it was well boiled, I took out my knife, slashed a branch to make a skewer and started to grill my portion over the fire.

Apparently it was my ability with the knife rather than my bulging muscles or headband that led to my baptism as Rambo. (I'm happy to add that the name stuck with my ability to light fires and strike camp.)

Sunset over the river.

To get this far to the almost unvisited National Park of Chiribiquete required major logistical planning and a slight foolhardiness on our part. Nobody really knew how long the journey would take; information ranged from anywhere between 11 hours to several days. At 15,000 pesos ($7.50 US) a gallon of gasoline, we had to be sure and prepare well.

Rambo-esque Colombian military billboard.

So, in actual fact, Rambo was a reality to the people of the Huitoto tribe now guiding us.

Up until our arrival in Chiribiquete, the journey up the Caquetá, Yari and Pesai rivers had been defined completely by food. This was jungle living, after all – just as the jungle provides, she needs to be respected.

Everything was to be smoked or moqueado, in particular the chamo (or fish), as Adán put it in the local dialect. And when Adán wasn’t casting a line, and embarrassing us with his more-than-prolific hook-to-catch rate, he managed to snare one with a machete. It sounds unbelievable, but an unsuspecting sábalo drifted in close enough for this true jungle survivor man to catch it with a machete blow to the back of its head.

Gazing at the storm in the distance, my imagination wandered back to troubled times here. It's this kind of experience, and that which was to follow, that struck a chord in my soul. Here I was, in the distant hinterlands of my adopted country, seeing attitudes to the long running-conflict in Colombia up close and personal.

For now, though, I was Rambo.