Researchers from WCS’s Bolivia Program have documented a natural phenomenon new to science: the mass migration of a small, obscure fish known locally as the “chipi chipi.” WCS Conservationist Guido Miranda recently captured footage of the tea-colored Beni River virtually boiling over with millions of 1-inch long juvenile fish.
“It’s amazing that this natural wonder has gone unnoticed by science for all this time,” said Miranda, who is publishing a study on the new finding. “The new footage will help us better understand the migratory movements of these fish and to protect the population, which is utilized by local communities as a food source.”
Miranda and his colleagues in the Greater Madidi-Tambopata Landscape are not yet sure why the fish are migrating, but it appears that juvenile chipi chipis migrate upstream to complete their development into adult fish. Once in the foothills—it is thought—the adult fish breed, after which the fertilized eggs end up downstream where the next generation of chipi chipis hatch. After two weeks of development, the next wave of chipi chipis (which means “smallest” in the local Takana language) then migrate approximately 217 miles back into the foothills.
“The presence of this migratory event in the Beni River hints at the surprises that still await researchers in these biologically rich waterways,” said Dr. Julie Kunen, Executive Director of WCS’s Latin America & the Caribbean Program. “Conserving Amazonian waters is vital in protecting both the migrations of fish populations on which local peoples rely and the health of the Amazon River basin system at its source.”
The chipi chipi—also known by its scientific name Trichomycterus barbouri –is a member of the pencil catfish family, a group containing more than 100 species and ranging in size from 2-6 inches in length. Other members of the pencil catfish genus include a blind species that lives in deep caves, a member living in hot thermal springs, and one that lives up to 15,000 feet above sea level in the Andes (the highest occurring fish species in South America).
Every year in the months of February and March, the Beni River in northern Bolivia is filled with millions of juvenile chipi chipi fish, on their way into the Andes foothills to mature into adults and spawn.