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
Curlfin sole Curlfin sole The curlfin sole ("Pleuronichthys decurrens") is a flatfish of the family Pleuronectidae. It is a demersal fish that lives on soft bottoms at depths of between . Its native habitat is the subtropical waters of the eastern Pacific, from Prince William Sound, Alaska in the north to San Quintín, Baja California in the south. It can grow up to in length, and reach weights of up to , with females generally being larger than males. The curlfin sole is a right-eyed flatfish with large, closely set eyes and a small mouth. The upper surface is reddish brown to