Sueur and colleagues David Mackie and Windmill, engineers at the University of Strathclyde in Glasgow, Scotland, began to investigate. They published their results in the journal PLoS ONE.
"We had a bit of trouble to start with because we thought the sounds were coming from relatively larger insects because the sounds were so loud," Windmill told Discovery News. "After bringing insects into the lab, we figured out it was this one."
The fact that people along the water's edge can hear the sounds indicates just how loud they are. Only 1 percent of sound released in water is transferred into the air above.
The researchers recorded the boatman making a series of chirps that peaked at 99 decibels. Adjusted for the insect's tiny size, this is the loudest sound produced by any animal.
Typically, larger animals make louder sounds.
"This small aquatic insect constitutes a major exception to this rule," said Fernando Montealegre of the University of Bristol, U.K.
The loudest sound ever recorded in an absolute sense was a 236-decibel burst from a sperm whale.