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
RV Platessa in survey logbooks, collected in 1931, 1937, 1946–50, and 1968. These historical measurements have revealed that the ‘sechhi depth’ was much deeper (and therefore water more transparent) in the past compared to today, and thus that the North Sea has become much more turbid. The Suffolk Record Office holds a photograph captioned ""survey ship "Platessa" LT 205 in Lowestoft harbour after being escorted back by the Gorleston lifeboat Khami having sprung a leak whilst working in the Smiths Knoll area"", dated 5th October 1968 (after leaving MAFF service). RV Platessa RV "Platessa" (LT205) was a fisheries research vessel that was