摘要 |
<p>System for surveying uptake or feed by fish wherein the feed particles are detected by the sonar-principle in a horizontal zone without fish around a transducer/sonar. The zone about the transducer is established by using a cylindrical net and the sound waves being reflected from the feed particles are emitted in the frequency interval about 670 kHz to distinguish between feed particles and possibly other material in the measurement zone. A device is also described which is suited for such detection of feed uptake.</p> |