When to Go
River levels are high during the rainy season (December to May), making for swifter travel. At this time mosquitoes, black flies and other insects are at their highest concentrations; definitely cover up at dawn and dusk when they come out in full force.
Even during the rainy months, mornings are often clear. Up to 5000mm of rain has been reported in some of the more inland areas, although San Miguel is somewhat drier. The drier months of September to the start of December are usually less buggy, and you have a better chance of seeing wildlife, although river navigation may be limited.