The method of fishing probably is older than modern humans. In fact, there probably would not be modern humans if ancestors had to outsmart the wily trout with a royal coachman dry fly plunked in the middle of a mayfly hatch.
The bipedal hominids somehow learned of the efficiency and method to poison fish. This is not unsportsmanlike. The early human was trying to feed the wife and kids back in the cave. The method is not unsportsmanlike today in remote areas, either, although government officials are not impressed.
That is why Fuerza Pública officers flew to the banks of the Río Telire near Bajo Bley, Talamanca, to dismantle a dam presumably erected by natives there.
The Ministerio de Seguridad Pública said that some in the area are accustomed to make a plant-based poison that affects fish but not humans. They pour this potion upstream and let the disoriented fish accumulate at makeshift dams. Similar techniques are employed by Amazonian natives. Environmentally sensitive locals said that such dams are a frequent occurrences. The case has been reported to the environmental ministry, said officers.