Reducing the short-term mortality of juvenile school prawns (Metapenaeus macleayi) discarded during trawling

doi:10.1016/j.icesjms.2006.03.008

ICES Journal of Marine Science: Journal du Conseil 2006 63(5):831-839; doi:10.1016/j.icesjms.2006.03.008

This Article

	Full Text
	FREE Full Text (PDF)
	Alert me when this article is cited
	Alert me if a correction is posted

Services

	Email this article to a friend
	Similar articles in this journal
	Alert me to new issues of the journal
	Add to My Personal Archive
	Download to citation manager
	Request Permissions

Google Scholar

	Articles by Macbeth, W. G.
	Articles by Wooden, M. E.L.
	Search for Related Content

PubMed

	Articles by Macbeth, W. G.
	Articles by Wooden, M. E.L.

Social Bookmarking

	What's this?

Reducing the short-term mortality of juvenile school prawns (Metapenaeus macleayi) discarded during trawling

William G. Macbeth^a^,b^,c^,_*, Matt K. Broadhurst^a^,b^,c, Brian D. Paterson^d and Michael E.L. Wooden^a^,b^,c

^a NSW Department of Primary Industries (NSWDPI), The University of New England, National Marine Science Centre (NMSC) PO Box J321, Coffs Harbour, New South Wales 2450, Australia
^b Fisheries Conservation Technology Unit (FCTU), The University of New England, National Marine Science Centre (NMSC) PO Box J321, Coffs Harbour, New South Wales 2450, Australia
^c School of Environmental Sciences & Natural Resource Management, The University of New England, National Marine Science Centre (NMSC) PO Box J321, Coffs Harbour, New South Wales 2450, Australia
^d Bribie Island Aquaculture Research Centre, Department of Primary Industries and Fisheries PO Box 2066, Bribie Island, Queensland 4507, Australia

^_*Correspondence to W. G. Macbeth: tel: +61 2 9527 8411; fax: +61 2 9527 8567. e-mail: will.macbeth{at}dpi.nsw.gov.au.

A field experiment was carried out in southeastern Australiato assess the short-term mortality and stress incurred by juvenileschool prawns (Metapenaeus macleayi) discarded from an estuarinetrawler. Some 35% of the prawns died up to 72 h after beingcaught in a trawl, exposed to air during sorting and separationfrom the retained catch (as per normal commercial procedures),then discarded into replicate cages. Total mortality was partitionedinto that caused by trawling (about 16% of mortalities), andby subsequent sorting and grading (about 19%). Assuming thatthe majority of the non-penaeid bycatch is excluded from trawls(by the use of bycatch reduction devices), the latter mortalitiescould be almost eliminated by sorting and separating unwantedschool prawns in water-filled compartments. Emersion stresswas measured as concentrations of L-lactate in the haemolymph,which were elevated for at least 40 min following capture, butsimilar among all trawled treatments. L-lactate levels decreasedwithin the first 24 h post-capture, then remained constant overat least the next 48 h, and were greater than baseline levels.The potential benefits associated with subtle changes to handlingpractices onboard estuarine trawlers are discussed.

Keywords: discard, estuarine fisheries, L-lactate, Metapenaeus macleayi, mortality, penaeid, prawn, square-mesh codend, stress, trawl

Received 11 November 2005; accepted 11 March 2006.

Add to CiteULike CiteULike Add to Connotea Connotea Add to Del.icio.us Del.icio.us What's this?

This article has been cited by other articles:

M. K. Broadhurst, R. B. Millar, and S. S. Uhlmann
Using a double codend to reduce discard mortality
ICES J. Mar. Sci., December 1, 2009; 66(10): 2077 - 2081.
[Abstract] [Full Text] [PDF]