At up to 10 feet and 440 pounds, the arapaima fish is an important source of food for people of the Amazon and other locations where the fish lives, According to National Geographic.
Based on a recent discovery by Dr. Ronald Stewart of the SUNY College of Environmental Science and Forestry (ESF), fishermen will now have quality and variety in their arapaima fish. Quantity, however, remains an issue.
Since the 1860s, scientists have accepted the presumption of British scientist Aflred Gunther that only one species of arapaima fish existed, even though previous to Gunther's research four species had been recognized, reported ESF. After studying the giant fish in Guyana and Brazil, however, Stewart suspected - and eventually proved - otherwise.
"Until this year, no taxonomist has questioned Günther's opinion about these iconic fishes," Stewart wrote in his report.
In addition to Stewarts' visits to other countries, he studied preserved specimens of arapaima at the Natural History Museum. He would eventually distinguish five species of the fish, according to ESF.
Stewart's fifth and most recent discovery (at the Instituto Nacional de Pesquisas da Amazônia in Manaus, Brazil) goes by the scientific name A. leptosome, which references its slender body, according to ESF.
"Everybody for 160 years had been saying there's only one kind of arapaima. But we know now there are various species, including some not previously recognized. Each of these unstudied giant fishes needs conservation assessment," Dr. Stewart said.
Indeed, the importance of Stewarts work extends beyond a scientist's need for classification. Because of their size and taste, arapaimas are farmed commercially in the sensitive environment of stock ponds, ESF reported.
"Failure to recognize that there are multiple species has consequences that are far reaching," Stewart said. "For example, there is a growing aquaculture industry for arapaima, so they are being moved about and stocked in ponds for rearing. Eventually pond-reared fishes escape and, once freed, the ecological effects are irreversible. A species that is endangered in its native habitat may become an invasive species in another habitat. The bottom line is that we shouldn't be moving these large, predatory fishes around until the species and their natural distributions are better known. Given the uncertainties, precaution is needed."
Arapaimas are also heavily fished in the Amazon so their numbers are constantly low, according to the study. If all of them are lumped into one category, how can game managers determine which variety is most at risk?
Watch a fisherman catch an enormous arapaimas (doesn't look to be the A. lepotosome) below:
