Submersible acoustic transmitter, low frequency transducer, loudspeaker, sounder, developed to attract fish

FishCall

Overview

Sensor: Acoustic transmitter
Frequency: Programmable from 200 Hz to 250 Hz
Transmitting range: ~1.5 km in radius
Beam transmitted pattern: Omnidirectional
Transmission interval: User programmable
Operational depth: Up to 50 meters
Battery life: 1 week (rechargeable). Option for external power supply instead of battery.
Control chassis material: Stainless steel and aluminium

Description

FishCall is a submersible acoustic transmitter (sounder) developed for sending low frequency sound underwater to attract fish to the sound source. It is made of watertight plastic cylinder containing transducer (underwater loudspeaker), two 12V batteries and electronics required to start and program the sound signals. The user can define transmitting range to be from 200 Hz to 250 Hz. It is also possible to define intervals of sound transmissions.

Examples of Application

The main objective with the FishCall was to develop a new and environmentally friendly fishing technique where sound signal is used to attract fish to the sound source platform. In a study using FishCall it was shown that it's possible to use the acoustic transmitter to send sound signals at low frequency to caged fish, train them to respond to the sound and lead them to the sound source where they are rewarded with food.  It was also shown that fish quickly learn from trained fish and follow the leader to the sound source.

Although it has only been tested in a sea cage, it should also be possible for a trained fish to lead a school of wild fish into a trap and thereby facilitating capture or ranching of wild fish. Read more about the scientific study here.

Nature magazine published an aricle in the April 2011 issue about the FishCall.  Read the article in Nature.

With the unique technology of a powerful loudspeaker low frequency sounder it also opens up doors for various other applications that marine biologists may have.