caa a22 4500 397550855 CHVBK 20180308164749.0 cr unu---uuuuu 161202e199604 xx s 000 0 eng 10.1006/jmsc.1996.0040 doi (NATIONALLICENCE)oxford-10.1006/jmsc.1996.0040 Mutlu Erhan Institute of Marine Sciences, Middle East Technical University, PO Box 28, 33731 TR, Erdemli, Icel, Turkey [tel: +324 521 2406; fax: +324 521 2327] Target strength of the common jellyfish (Aurelia aurita): a preliminary experimental study with a dual-beam acoustic system [Elektronische Daten] [Erhan Mutlu] An enclosure was designed for experiments estimating the target strength (TS) of the common jellyfish (Aurelia aurita) in the Black Sea. A BioSonics echosounder (Model 102) equipped with 120 and 200 kHz dual-beam transducers was used for the measurements. The average acoustic cross-section for each size class was used in functional regression equations to relate the mean TS (dB) of jellyfish to its disc diameter d (cm) and wet weight W (g). These were found to be as follows: TS=14.72 log d−74.63 and TS=5.71 log W−69.41 at 120 kHz; TS=39.65 log d−104.38 and TS=14.53 log W−88.07 at 200 kHz. The TS values were found to fluctuate periodically with time. The results showed a variation of −54 to −67 dB at 120 kHz for 15.5 cm diameter individuals, with a period of 7.5 to 10 sec; and a variation of −58 to −68 dB for 11.5 cm individuals at 200 kHz, with a period of 6 to 12.5 sec. © 1996 International Council for the Exploration of the Sea Regular Articles nationallicence Black Sea nationallicence jellyfish nationallicence target strength nationallicence ICES Journal of Marine Science Oxford University Press 53/2(1996-04), 309-311 1054-3139 53:2<309 1996 53 icesjms https://doi.org/10.1006/jmsc.1996.0040 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1006/jmsc.1996.0040 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Mutlu Erhan Institute of Marine Sciences, Middle East Technical University, PO Box 28, 33731 TR, Erdemli, Icel, Turkey [tel: +324 521 2406; fax: +324 521 2327] NATIONALLICENCE 773 0- ICES Journal of Marine Science Oxford University Press 53/2(1996-04), 309-311 1054-3139 53:2<309 1996 53 icesjms Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford