What is a Quantitative Echosounder?
A “Quantitative echosounder” or “Scientific echosounder” is an acoustic instrument designed for scientific research, utilizing the principle of backscattering acoustic signals (ultrasonic wave) to detect and assess the quantity of aquatic organisms, such as fish biomass, and spatial distribution.
From the Tragedy of the Titanic to the Rise of Echosounder Technology
The origin of the echosounder was begin from the sinking of the Titanic, which struck an iceberg off Newfoundland, Canada in 1912. This accident sparked the development of an iceberg detector from a long distance. During experiments, researchers accidentally discovered sound reflections from the sea bottom, which eventually led to the development of the fisheries echosounder for locating school of fish – hugely beneficial for capturing fishery resources.
By 1968, this technology evolved into the scientific echosounder for aquatic resource surveys. Since then, it has continued to advance and remains a critical instrument in fisheries research today.
Principle of echosounder
Echosounders operate based on fundamental acoustic pulse-echo principles, particularly;
The efficient propagation of sound over a long distance in water – it has an advantage in underwater exploration compared with so-called electromagnetic waves, such as light and radio waves, underwater sound propagates over significantly longer distances.
The reflection of sound waves when they encounter underwater objects – sound speed at
a much higher speed in water—approximately 1500 meters/second, compared to 340 meters/second in air, making it ideal for underwater sensing.
