Seahorse Acoustic Reflection on Active and Passive Moving Condition : A Prelyminary Observation in Watertank

Dony Apdillah, Indra Jaya, Henry Munandar Manik, Totok Hestirianoto, Try Febrianto

Abstract


Identification and estimation of seahorse population in the marine environment are difficult to obtain. Nowadays, the observations use visual techniques, biologic and statistics. Bio-statistics approach has some limitations, such as times consuming and low accuracy. An approach was required to provide more accurate information, comprehensive, and based on telemetry (underwater acoustic). Acoustic reflection is an important information to observe underwater objects that can be used for stock assessment and behavioral studies. This research is a preliminary observation and measurement of seahorse Target Strength (TS). The results show that there are differences in TS value of seahorse at the active and passive moving condition. The fluctuations of TS values in active conditions are higher than those in passive conditions.  This study has also found that the average TS value of seahorse in active moving conditions is -54.49 dB (± 3 dB). It is greater than the mean TS value in passive moving conditions -59.64 dB (± 3 dB). The approach of immobile fish (the passive moving condition) on the seahorse is better to increase the correlation value between TS to size. The relationship between TS and the size of the seahorse are discussed in the results of this study

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References


Balk, H., Lindem, T., 2015. Sonar 4 and Sonar 5-Pro post-processing systems, Operator manual version 6.0.3, 494 p, Lindem Data Acquisition Humleveien 4b. 0870 Oslo, Norway

Burczynski J J, Johnson R L. 1986. Application of dual-beam acoustic survey techniques to limnetic populations of juvenile sockeye salmon (Oncorhynchus nerka). Canadian Journal of Fisheries and Aquatic Sciences, 43(9): 1776–1788.

Correia, M., Palma J., Koldewey H., Andrade J.P. 2014. The use of a non-invasive tool for capture–recapture studies on a seahorse Hippocampus guttulatus population. Journal of Fish Biology. 84(4). 872-884.

Curtis, J.M.R. 2007. Validation of a method for estimating realized annual fecundity in a multiple spawners, the long-snouted seahorse (Hippocampus guttulatus), using underwater visual census. Fishery Bulletin 105, 327–336.

Dawson, J.J and W.A. Karp. 1990. In situ Measures of target strength variability of individual fish. Rapp. P.V. Reun. Cons. Int. Explore. Mer. 189: 264-273.

Ehenberg, J.E. 1984. The biosonic dual beam target strength measurement system.. FAO Fish. Circ. 778: 71-78.

Foster, S.J., Vincent A.C.J. 2004. Life history and ecology of seahorse: implications for conservation and management. Journal of Fish Biology 65: 1-61.

Horne J.K. 2003. The influence of ontogeny, physiology and behaviour on the target strength of walleye pollock (Theragra chalcogramma). Ices Journal of marine science. 60: 1063-1074.

IUCN Red List of Threatened Species. Version 2014.3. . Accessed 22 December 2014.

Ona E. 1990. Physiological factors causing natural variations in acoustic target strength of fish. Journal of the Marine Biological Association of the United Kingdom, 70(1): 107-127.

MacLennan, D. N., Fernandes, P. G., and Dalen, J. 2002. A consistent approach to definitions and symbols in fisheries acoustics. – ICES Journal of Marine Science, 59: 365–369.

Manik, H.M. 2009. Quantification of Tuna Fish Target Strength Using Quantitative Echo Sounder. Ilmu dan Teknologi Kelautan Tropis. Juni 2009. vol. 1 (1) : 33-38

Medwin, H., and Clay. C.S. 1997. Applied Ocean Acoustics: Fundamentals of Acoustical Oceanography. Academic Press, New York. 712 pp.

Project Seahorse, 2014. http://www.projectseahorse.org/ accessed December 2014

R Core Team. 2016. R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria. URL https://www.r-project.org/

Sánchez, V.R., L.E. Encina, A.R. Ruiz, A Monteoliva, R.S., Carmona. 2016. Horizontal target strength of Cyprinus Carpio using 200 kHz and 430 kHz split-beam systems. Fisheries Research 174 (2016) 136–142.

Simmonds, E.J., Maclennan D.N., 2005. Fisheries Acoustic Theory and Practice. Second Edition. Oxford: Blackwell Science Ltd. Oxford, UK, 437pp.

Simrad, 2012. Installation manual, Simrad EK15 Multi purpose scientific echosounder, Kongsberg Maritime AS, ISBN 978-82-8066-147-0.

Yip, M., Lim, A., Chong, V., Lawson, J., & Foster, S. (2015). Food and feeding habits of the seahorses Hippocampus spinosissimus and Hippocampus trimaculatus (Malaysia). Journal of the Marine Biological Association of the United Kingdom, 95(5), 1033-1040.




DOI: http://dx.doi.org/10.20884/1.oa.2018.14.1.387

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