Castanha do Brasil

Its dry season here in Amazonas now, the tropical downpours are few and far between, but when they do randomly appear they are spectacular. The flood waters have passed their seasonal height and are now receding. The people who live near the rivers say the fishing is good from September onwards as abundant amounts of fish including the popular Tambaqui have been feeding on fallen fruit and insects from the trees and they are flushed out of the flooded forest along with the water so they are easier to catch.

As for me, I am currently living in a disused basement, sleeping in my hammock at a house on the outskirts of Manaus city that backs on to the rainforest. Its remoteness from the city is probably beneficial as I am keeping my spending to a minimum. Also it’s nice to still be in touch with the jungle. I had to evict large nests of termites, spiders, cockroaches, bees and bats then clean and paint before i could sling my hammock there. It doesn’t take long for the jungle creatures to reclaim their space. I have seen monkeys, bats, large snakes, Iguanas, frogs, marmosets and many different insects and colourful birds but nowhere near as many as i saw and heard on that last remote leg to Rio Purus.

I’m keeping busy doing various chores in return for the accommodation and some food, and I keep fit running, walking and swimming (I estimate I’ve probably covered close to 1000 kilometres since I’ve been here). I’m also reviewing the route ahead and replenishing broken kit, as well as learning a new Portuguese word every day.

I plan to continue my trek in a few weeks time, as soon as water levels drop sufficiently for me to continue. By early September, river levels should have dropped just about enough to enable me to cross on foot to Coari then on to Tefe. It will still be a difficult traverse because there is still a significant amount of flooded forest and the rivers won’t be at their lowest until December, but I will have to take the risk though, as I am desperate to get moving again!

The spare time has given me the opportunity to reflect more deeply on the global importance of this incredible rainforest and its unparalleled biodiversity and how it plays its part in helping to keep our planet healthy and the vital connectedness of all its residents, trees and rivers.

After losing two of my teeth on that last traverse to Rio Purus trying to open the shell of a brazil nut, I thought I should write about this great example of how all life here is interdependent and connected. Brazil nut trees (Bertholletia excelsa) are among the giants of South America’s Amazon. They tower up to 200 feet high, and their spreading canopy, branches and flowers provide habitat and food for a multitude of forest creatures. It is mind-boggling that a brazil nut seed can lay dormant in the soil for years, and retain all the information sealed within its shell to grow into this giant of the rainforest with a lifespan of up to a thousand years – all with such a limited supply of sunshine and soil. The Brazil nut, known here as “Castanha do Brasil’ or “Castanha do Pará”, is also the foundation of a global business worth many millions of dollars a year. The pods crash to the forest floor during the wettest times of the year (December – March), and collectors (castanheiros) harvest the nuts by gathering the fallen pods cutting them open with machetes and sometimes walking many kilometres along jungle tracks to a boat for transportation carrying up to 60 kilograms at a time in a woven basket. A single mature tree can produce more than 250 pounds of Brazil nuts a year. In the past Brazil nut trees presented a puzzle to biologists. They couldn’t figure out what kind of animal was able to break open the rock-hard pods so that the nuts could grow into new trees. Also it wasn’t clear why only trees in undisturbed tropical forests bear fruit.

So how do the nuts get free from their rock-solid pods in the rainforest, when it seems that no animal has jaws powerful enough to break open the thick solid pods? The answer, it turns out, is the Agouti — a small rodent that looks a bit like a large, tailless squirrel. Agoutis have small, chisel-like teeth that can penetrate the Brazil nut’s seed case. They eat some of the nuts, but they also carry away and bury others for future meals. If forgotten, these seeds can stay dormant in the soil for years, waiting for the perfect conditions to germinate and grow into a new Brazil nut-tree.

The Agouti isn’t the only animal that Brazil nut trees need to survive. They also rely on specific bees, and even other plants. Orchid bees (Euglossini) visit flowering Brazil nut trees to collect nectar, and transport the pollen from tree to tree, fertilising the flowers and helping the trees produce the seed pods. In turn, the bees depend on a specific orchid to survive, as the male bee needs fragrance from a particular orchid to attract females… so If the surrounding forest is damaged and the orchids disappear, so will the bees — and the incredible Brazil nut-tree. (See video clip below)

Brazil nuts are what I would consider to be a ‘Super-food’ Read about the nutritional, medicinal and culinary uses here.

Watch the amazing BBC TV video clip below to see this process in action (Copyright © BBC). Click on the image, not the white arrow, to play it!


You can find out more about the series at the BBC website, and you can purchase the BBC Earth DVD series Secrets of our Living Planet here at


The Amazon’s biogeochemical exchanges are important on multiple fronts. For starters, the region’s immensity, unparalleled biodiversity, and critical role in the planet’s carbon and water cycles means that what happens in the Amazon doesn’t stay in the Amazon. The fates of this and other tropical forests are intimately connected to the fate of the rapidly changing planet in the Anthropocene, the current geological age in which humans have become a dominant force affecting Earth’s climate and environmental processes. As increases in global temperatures unleash ecological and meteorological mayhem around the planet, understanding how this iconic biome works has become more important than ever”.
Source BioGraphic

And on a last note, if anyone reading this blog from the UK happens to be visiting Manaus in August and wouldn’t mind bringing a few small items of kit here for me, please get in touch via my contact page, i would really appreciate it.


Header photo. Resting in my Hennessy hammock. Room with a jungle view. (Amazonas Brazil)


“And above all, watch with glittering eyes the world around you because the greatest secrets are always hidden in the most unlikely places” (Roald Dahl)

A towering brazil nut-tree (Pará Brazil)



An Agouti, The only animal able to open the brazil nut pod. (Marajó Brazil)


Photo 13-11-2009 07 10 20 (1)

Opening a pod of brazil nuts (Amazonas)



A giant beetle – one of many interesting insects I’ve photographed here. (Amazonas Brazil)



Water receding, rushing through flooded forest. (Amazonas Brazil)







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