The DDD is an acoustic deterrent that effectively prevents marine mammal bycatch thanks to an efficient technique of interaction with their echo-localization system (sonar). To use the DDD is very simple: the DDD must simply be attached to the fishing gear by being hung on the nets or to the longline. In contact with water, the DDD activates. It transmits modulus signals that interfere with the acoustic perception system of the cetaceans and disrupts their hunt for prey in the nets or lines.The level of the DDD emissions doesn’t produce any harm to mammals or fish. These last are insensitive to the frequencies emitted.
DDD03H (High Model)
Usage: short gillnets, trawl and/or purse nets, longlines.
Average battery charge duration: 40 hours.
Horizontal distance between two devices: between 300 and 500 m.
Vertical distance between two devices (on the long lines): from 60 to 80 m.
DDD 03U (Ultra model)
Use: on single longlines.
Average battery life: 8 – 12 hours.
Vertical distance between two devices: from 40 to 60 m.
Transmission frequency: 5 to 500 kHz
Weight: 940gr.
Height: 215mm. Diameter: 62mm.
Internal Rechargeable Battery: 1.6 Ah NiMH (cachetées).
The DiD is the interactive evolution of the standard DDD models. It produces the ultrasounds only when it detects the presence of the dolphins in the area, by means of its “hearing” circuitry, that is activated by the “clicks” emitted by the mammals. The signals produced by the DiD are identical in sequence but random in the intervals in order to prevent the animals from becoming accustomed to the signals. The ability of the DiD to be activated only in the presence of cetaceans improves its efficiency by adding the surprise effect and increases the life of the batteries and the duration of the charge.
Average battery life:
Up to 1000 charging/discharging cycles
Battery charge duration:
Depending on the frequency of cetacean presence.
Transmission Frequency: Random 5 to 500 kHz
Weight: 940gr.
Height: 215mm. Diameter: 62mm.
Internal rechargeable Battery: 1.6 Ah NiMH (cachetées).
