The MAD has been developed as a seabird deterrent for use in situations where integrated weight lines or torrey/streamer lines are not used, or as a supplementary deterrent where bycatch mitigation is particularly challenging. How harmful different laser beams are for seabird eyes is pending scientific review, and the laser add-on for the MAD is thus restricted for controlled trials only for the time being.

Acoustic deterrence of birds has been practiced for a long time, as has laser deterrence of birds at airport and crop fields. The MAD brings together both methods in a single device, yet either solution can be acquired or used separately.

The laser is only effective in darkness or in low light conditions with significant air humidy, where the laser beam can be seen passing through the air. The birds perceive the visible laser beam as a solid object and avoid it - the "laser stick effect" known from airport- and cornfield bird protection. In addition, the laser creates a very bright spot when it is reflected from rough water or foam, which may dazzle and deter the birds. The laser in use in this beta product is classified as a Class 4 laser at its maximum setting of 1200mW. Its power can be reduced in steps of 200mW down to a minimum of 200mW. One of the objectives of on-going trials is to explore how low effects are sufficient. The beam has a wavelength of 532nm and is free from infrared (heat) wavelengths.

A set of field trials were performed in Alaska in October 2015 by Dr Ed Melvin of the Washington Sea Grant, University of Washington. The trials tested this unit side by side with a competing product that has already been released for sale. While the data was limited because of poor fishing, there were indications that the effectiveness of laser may be quite species-specific as well as dependent on the birds' orientation relative to the beam.

Until both the safety of laser for seabird eyes, and effectiveness in deterrence, have been deemed credible by scientists, Fiskevegn restricts applications of laser to controlled trials only.

The acoustic unit builds on a well-proven core that is manufactured by the global market leader in long-range acoustic hailers, LRAD Corporation. It is controlled by an MP3 playback unit that has capacity for hours of recordings or that can loop selected sound files indefinitely.

Fiskevegn's field trials to date suggest that the acoustic unit is as effective or more effective than the laser, and it adds the significant benefit of working in daylight. This is important since there is some risk of seabird by-catch also when hauling the lines, and this operation generally occurs during day-time.

At this stage we focus further development on determining whether seabirds accomodate to the acoustic deterrent, and if they do, to develop transmit patterns that are both effective and unpredictable.

An highly informal preview of the MAD in action in field trials can be seen in the video below. 


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