The walk in the rainforest (Sunday June 11)

Today we're heading into the forest for an 'explanatory' walk, where Felipe will show us a variey of trees and explain their uses and properties. We've been told to wear long pants tucked into socks and boots, and in addition we're given special leg shields, to protect us from both ticks and snake bites.

The first part of the journey is in the boat, which glides over the still water, until we suddenly bump against the edge of the dense forest.

We all climb out and struggle up a bank covered in twisted roots and we're relieved when Joab, Felipe's collegue, hands us each walking stick he's just made from hacking off the leaves of a sturdy branch. Felipe warns us not to touch any tree trunks, which may be coveed in spines or hide snakes - he also says to walk lifting our feet rather than sliding them on the ground, which could startle a snake, "and then she bites," he says cheerfully. We ask him if he's ever been bitten, "Oh, yes," he says and then shows a big gouge on his arm where a crocodile took hold, but let him go.

The trees hold many secrets known to indiginous people, such as Felipe, who learnt them as a kid with walking through the forest with his dad. The sap of one has healing properties and can be used to treat a snake bite, the bark of another helps with respiratory problems. A deliciously scented bark, called a 'preciosa' (precious) is used, he explains, to 'calm the women'. Finally we see the innocent looking milky sap, known as curare, which the indians use for hunting, but is also employed for intubating patients. The trees also form natural sculptures, a parasite twisted around a tree trunk and the giant felled castanheira, whose roots could not hold its weight.

The vegetation is closing in around us on all sides and the heat and humidity are quite overwhelming. It is difficult to breathe and we're soaked through with sweat. "How long to the river?" I ask. As soon as we near the water the atmosphere changes considerably, and, once on the water, we relish the fresh breeze drying all our olive green dry-fit clothes.

- and admire the amazing reflected landscapes in the dark acidic Rio Negro.

We feel pretty done for the day, and after lunch we amble the 500 steps to our far away cabin and have our first Cayman sighting - a quiet ap. 2 meter long specimen with a yellow face and focused dark eyes. When we continue and round the last corner to our cabin we hear a rather frightful crunching sound. Turns out there's another, larger, Cayman chomping on a branch just beneath us.

After a rest we feel the wisest thing is to go to the (wire-mesh protected) pool and order caipivodkas. I teach the bartender to make one with pitaya (dragon fruit) and one with kiwi - both fruits are served at breakfast. Delicious!