Stock Assessment of Sharks in the Northern Part (Iranian Waters) of the Persian Gulf
Agriculture, Forestry and Fisheries
Volume 3, Issue 5, October 2014, Pages: 397-400
Received: Sep. 28, 2014;
Accepted: Oct. 21, 2014;
Published: Oct. 30, 2014
Views 2587 Downloads 157
Nassir Niamaimandi, Iran Shrimp Research Institute, P.O.Box: 1374, Bushehr-Iran
Toraj Valinassab, Iranian Fisheries Research Organization, Tehran-Iran
Gholam-Abbas Zarshenas, Iranian Fisheries Research Organization, Tehran-Iran
This study was analyzed the annual catch and trawl survey data of sharks in the northern part of the Persian Gulf (26˚30΄ to 30˚00΄N and 49˚00΄ to 56˚00΄E) from 2004 to 2009. Trawl survey was conducted by research vessel Ferdous, equipped with bottom trawl nets in meshes 400mm and 80mm at body and cod-end respectively. Ten stratums were selected in the study area and 199 stations were randomly trawled. The density (CPUA) of shark resources was estimated based on swept area method. Annual total catch was obtained from Iranian fisheries organization (Shilat). The results of catch per unit area showed 250.7 kg/nm2 in 2004 to 49.7 kg/nm2 in 2009. There was a high degree of variability of CPUA among different areas and the maximum was estimated 1870.8 kg/nm2 in Nayband and Mogham. In catch composition data, sharks have a decreasing trend from 4.2% in 2004 to 2.9% in 2009 that shows a decline with an annual average 1.3% during 2004-2009.This results suggesting that the shark resources are overexploited and the current effort is far higher than the effort required harvesting optimum yields.
Stock Assessment of Sharks in the Northern Part (Iranian Waters) of the Persian Gulf, Agriculture, Forestry and Fisheries.
Vol. 3, No. 5,
2014, pp. 397-400.
Abella, A. 2010. Stock assessment models and their application to skates. In: Serena F., Mancusi C., Barone M. (eds). Field identification guide to the skates (Rajidae) of the Mediterranean Sea. Guidelines for data collection and analysis Biol. Mar. Mediterr., 17 (Suppl. 2): 204 p.
Clarke, S.C., McAllister, M.K., Milner-Gulland, E.J., Kirkwood, G.P., Michielsens, C.G.J., Agnew, D.J., Pikitch, E.K., Nakano, H., Shivji, M.S., 2006. Global estimates of shark catches using trade records from commercial markets.Ecological letter, Vol. 9. 1115-1126.
McAuley, R., Newbound, D., Ashworth, R., 2002. Field identification guide to western Australian sharks and shark-like rays. Department of fisheries, Pert, Western Australia. Fisheries occasional publication, No. 1
Moore,, A.B.M., Ward, R.D and Peirce, R. 2012. Sharks of the Persian Gulf: a first annotated checklist (Chondrichthyes: Elasmobranchii). Zootaxa 3167: 1–16.
Simpfendorfer, C.A., Freitas, G.F., Wiley, T.R., Heupel, M.R. 2005. Distribution and habitat partitioning of immature bull sharks (Carcharhinusleucas) in a Southwest Florida Estuary. Estuaries 28:78–85
Simpfendorfer, C.A., Cortés, E., Heupel, M., Brooks, E., Babcock, E., Baum, J., McAuley, R., Dudley, S., Stevens, J.D., Fordham, S. and Soldo, A. 2008. An integrated approach to determining the risk of overexploitation for data-poor pelagic Atlantic sharks. ICCAT SCRS/2008/140.
Sparre, P., Venema, S.C. 1992. Introduction to tropical fish stock assessment, part 1-manual. FAO fisheries technical paper 306/1. 311-314.
Worm, B., Davis, B., Kettemer, L., Ward-Paige, C.A., Chapman, D., Heithaus, M.R., StevenT.Kessel, S.T., SamuelH.Gruber, S.H. 2013. Global catches, exploitation rates, and rebuilding options for sharks. Marine policy 40. 194-204.