A design study of an acoustic system suitable for differentiating between orange roughy and other New Zealand deep-water species

Using the simple slab-cylinder acoustic model for fish, developed by Clay and Horne [J. Acoust. Soc. Am. 96, 1661–1668 (1994)], the target strengths of three of New Zealand’s deep-water fish species, namely orange roughy, black oreos, and smooth oreos, have been derived. The target strengths derived for the model fish have been found to be in reasonable agreement with currently accepted target strength values. These three model fish were used in a study to test the species discrimination of a chirp sonar system. Chirps of center frequencies 40, 80, and 160 kHz and bandwidth of 10, 20, and 40 kHz have been used to acoustically illuminate the three fish species listed above and the matched, filtered responses to the chirps determined. The effect of the response of transducer or system bandwidth has also been investigated. It has been found that the bandwidth of the chirp is much more important for resolving detail in a fish target than the chirp center frequency. A bandwidth of at least 20 kHz, and preferab...

[1]  Jane Doonan Quentin Blake, The Children's Laureate: Selected Picture Books , 2000 .

[2]  K. Foote Importance of the swimbladder in acoustic scattering by fish: A comparison of gadoid and mackerel target strengths , 1980 .

[3]  W. C. Leggett,et al.  Hydroacoustic Signal Classification of Fish Schools by Species , 1988 .

[4]  Rudy J. Kloser,et al.  Avoidance of a camera system by a deepwater fish, the orange roughy (Hoplostethus atlanticus) , 1995 .

[5]  C. Clay,et al.  Ray representation of sound scattering by weakly scattering deformed fluid cylinders: Simple physics and application to zooplankton , 1993 .

[6]  C. Clay Composite ray‐mode approximations for backscattered sound from gas‐filled cylinders and swimbladders , 1992 .

[7]  Dezhang Chu,et al.  Application of pulse compression techniques to broadband acoustic scattering by live individual zooplankton , 1998 .

[8]  S. McClatchie,et al.  Target strength of an oily deep-water fish, orange roughy (Hoplostethus atlanticus) II. Modeling , 1999 .

[9]  Z. Ye Low-frequency acoustic scattering by gas-filled prolate spheroids in liquids , 1997 .

[10]  John K. Horne,et al.  Acoustic models of fish: The Atlantic cod (Gadus morhua) , 1994 .

[11]  M. Clark EXPERIENCE WITH MANAGEMENT OF ORANGE ROUGHY (Hoplostethus atlanticus ) IN NEW ZEALAND WATERS, AND THE EFFECTS OF COMMERCIAL FISHING ON STOCKS OVER THE PERIOD 1980-1993 , 1995 .

[12]  Sam McClatchie,et al.  Consequence of swimbladder model choice and fish orientation to target strength of three New Zealand fish species , 1996 .

[13]  M. Grigor,et al.  Role of wax esters in determining buoyancy inHoplostethus atlanticus (Beryciformes: Trachichthyidae) , 1990 .

[14]  Rudy J. Kloser,et al.  Acoustic assessment of the biomass of a spawning aggregation of orange roughy (Hoplostethus atlanticus, Collett) off south-eastern Australia, 1990-93 , 1996 .

[15]  K. Mackenzie Nine‐term equation for sound speed in the oceans , 1981 .

[16]  Alain Hillion,et al.  Narrowband acoustic identification of monospecific fish shoals , 1996 .

[17]  W. M. Haynes CRC Handbook of Chemistry and Physics , 1990 .

[18]  Rodney D. Hale,et al.  Acoustic species identification in the Northwest Atlantic using digital image processing , 2000 .

[19]  R. F. Coombs,et al.  Acoustic measurements of the population of orange roughy (Hoplostethus atlanticus) on the north Chatham Rise, New Zealand, in winter 1986 , 1989 .