RV Corella Fisheries Laboratory cooperated with the Admiralty Research Laboratory to identify fish detected by long-range sonar equipment installed at the Admiralty Experimental Station, Perranporth. The RV "Corella" was directed from the shore to an area some 65 km distant, that was returning a strong and extended echo. The "Corella" was able to correlate this target with shoals detected on a conventional echo sounder, and substantial catches of sprats were taken in the area using a midwater trawl. The RV "Corella" was used throughout the 1970s for pioneering studies on fish migration. Individual plaice ("Pleuronectes platessa") fitted with 300 kHz acoustic transponding
Teleost or deceive, while others such as lionfish have aposematic coloration to warn that they are toxic or have venomous spines. Flatfish are demersal fish (bottom-feeding fish) that show a greater degree of asymmetry than any other vertebrates. The larvae are at first bilaterally symmetrical but they undergo metamorphosis during the course of their development, with one eye migrating to the other side of the head, and they simultaneously start swimming on their side. This has the advantage that, when they lie on the seabed, both eyes are on top, giving them a broad field of view. The upper side is