Retention probability of purse seine grating sieve based on fish morphology

The retention-releasing patterns of the double-grid grating sieve placed on the deck of the purse seiners were revealed for four case species (Sardina pilchardus, Sardinella aurita, Engraulis encrasicolus and Boops boops) using a simulated data predicted from total length (TL) – maximum height (Hmax) and TL – maximum width (Wmax) regressions. To calculate these relationships, samples were collected during commercial purse seine operations between 3 April 2017 and 21 March 2018 in Izmir Bay, Aegean Sea (Turkey). Optimal Bar Spacing (OBS) values corresponding to minimum landing sizes or the length at first maturity were calculated separately for each species. OBS values were found 10.97 mm for sardine (Sardina pilchardus), 11.29 mm for round sardine (Sardinella aurita), 7.78 mm for anchovy (Engraulis encrasicolus) and 17.89 mm for bogue (Boops boops). The bar spacing regulations may constitute a promising management measure to release undersized fish for the purse seine fishery in the Aegean Sea.

[1]  A. Sala,et al.  Predictive models for codend size selectivity for four commercially important species in the Mediterranean bottom trawl fishery in spring and summer: Effects of codend type and catch size , 2018, PloS one.

[2]  B. Herrmann,et al.  CREELSELECT—A method for determining the optimal creel mesh: Case study on Norway lobster (Nephrops norvegicus) fishery in the Mediterranean Sea , 2018, Fisheries Research.

[3]  G. Gökçe,et al.  Fish Morphology and Barrier Trap Bar Spacing in Lagoon Fisheries along the Aegean Coast of Turkey , 2018 .

[4]  Nina A. H. Madsen,et al.  Predicting size selection of cod (Gadus morhua) in square mesh codends for demersal seining: A simulation-based approach , 2016 .

[5]  L. Krag,et al.  Understanding the size selectivity of red mullet (Mullus barbatus) in Mediterranean trawl codends: A study based on fish morphology , 2016 .

[6]  O. Soykan,et al.  Growth and reproduction of Boops boops, Dentex macrophthalmus, Diplodus vulgaris, and Pagellus acarne (Actinopterygii: Perciformes: Sparidae) from east-central Aegean Sea, Turkey , 2015 .

[7]  Cüneyt Suzer,et al.  THE AEGEAN SEA MARINE BIODIVERSITY FISHERIES CONSERVATION AND GOVERNANCE , 2015 .

[8]  A. Sala,et al.  Scientific, Technical and Economic Committee for Fisheries (STECF) - Landing Obligation - Part 6 (Fisheries targeting demersal species in the Mediterranean Sea) (STECF-15-19) , 2015 .

[9]  A. Campos,et al.  Relationships between opercula girth, maximum girth and total length of fish species caught in gillnet and trammel net selectivity surveys off the Portuguese coast , 2006 .

[10]  H. Özbilgin,et al.  Body shape and trawl cod end selectivity for nine commercial fish species , 2003, Journal of the Marine Biological Association of the United Kingdom.

[11]  H. Özbilgin,et al.  Determination of the Appropriate Hanging Ratios to Ease the Escape of Juvenile Red Mullet (Mullus barbatus L., 1758) and Annular Sea Bream (Diplodus annularis L., 1758) from a Trawl Codend , 2003 .

[12]  K. Stergiou,et al.  Comparative fixed gear studies in the Cyclades (Aegean Sea): size selectivity of small-hook longlines and monofilament gill nets , 2002 .

[13]  H. Lassen,et al.  Manual on estimation of selectivity for gillnet and longline gears in abundance surveys , 2000 .

[14]  Y. Matsushita,et al.  Investigation of trawl landings for the purpose of reducing the capture of non-target species and sizes of fish , 1997 .

[15]  M. Ben-Yami,et al.  Purse Seining Manual , 1994 .

[16]  A. K. Beltestad,et al.  Size-selection of mackerel and saithe in purse seine , 1994 .

[17]  D. MacLennan,et al.  Gear selectivity and the conservation of fish , 1990 .