Last Thursday I traveled to several rural areas outside of the city of Cochabamba to attend a day-long training in aquaculture systems.

Part of the training involved a trip to the Chapare, that part of Bolivia notorious for illicit coca production and a source of tension between the new Morales government and the United States.

We visited several trout farms of different sizes, from small, family-owned operations to large, semi-industrial trout farms. The experience left me with mixed feelings.

Trout farming has been a lucrative enterprise for many Bolivian farmers and entrepreneurs. Local demand in the nearby city center far outstrips the ability of the farmers’ productive capacity. High demand has created favorable market conditions for impoverished farmers; and trout farming has provided a much needed alternative source of income in a place where the temptation to provide coca to the narcotics market remains high.

Aquaculture experts tell me that this species of Rainbow Trout (Salmo gairdneri irideus) is well suited to production in captivity. The species is very similar to the more common scientific classification for Rainbow Trout (Oncorhynchus mykiss); however, the trout being produced in Chapare are said to be more robust with faster growth and reproduction rates. The taxonomic differences are subtle, and it is possible that we are dealing with different varieties of the same species, as they are capable of cross-breeding.

Unfortunately, this species of trout is not native to the region. After 15 years of trout production in aquatic systems that are directly connected to local watersheds, and ultimately feed into the Amazon river, one can imagine that hundreds, if not thousands, of exotic trout have been released into the environment.

The result has been a disaster for native fish species, and the impact on the ecosystem at large has yet to be assessed. I searched the web in vain looking for information regarding the effects of introduced Rainbow trout into the Amazon watershed.

This paucity of information has several possible explanations. Perhaps the information I am looking for has been gathered by Brazilian researchers, and is therefore in Portugese. Or, the information may be so specialized or obscure that only a small handful of researchers have collected it. More than likely, there is no comprehensive, landscape level research about Rainbow Trout’s impact on aquatic ecosystems in the Amazon. For what it’s worth, Oncorhynchus mykiss is listed on The Nature Conservancy’s invasive species list for the country of Brazil.

I make no claims at being on ichthyologist or an aquatic ecologist, but it is not difficult to imagine that aquatic ecosystem restoration after a massive exotic species invasion is extremely difficult, if not virtually impossible. Still, there is yet hope for a conservationist approach. Now more than ever there is a dire need for experimentation and implementation of mixed, self-regulating aquaculture systems with native species. Such an approach would diversify local economies and diets while providing an economically viable way in which valuable genetic resources can be preserved.

Although there is no shortage of human capacity and ingenuity in rural Bolivia, political will and social organization remain in short supply. For now, it seems, Rainbow Trout will continue to be on the menu in Bolivian restaurants.