Acronym BRD
Category
Fisheries
Title Experimental by-catch reducing devices in the demersal purse-seine fishery and evaluation of survivorship Programme Nat. Programme (supported by ESIF)
Instrument (FP6)
Contact Type (FP7)
Strand (Interreg)
NA
Theme (FP7)
Activity Area (FP6)
Regional Area (Interreg)
Action (COST)
NA
Specific Programme (FP7)
NA
Funding source National-European Coordinator Jorge Goncalves Coordinator email jgoncal@ualg.pt
Coordinator institution
CCMAR - Centre for Marine Sciences (Portugal)
Institutions involved
NA
Start year 2002 End year 2004 Funding (€) € 73,000 Website NA Summary The main objective of this study was to evaluate the efficacy of different selectivity devices in reducing by-catch and consequently of discards in the Algarve demersal purse seine fishery. While the demersal purse seine may have the same target species as the pelagic purse seine, it can also target high commercial value demersal species such as sea breams (Diplodus spp.) and the European sea bass (Dicentrarchus labrax). In this case it is largely the low value pelagic species such as chub mackerel and sparid juveniles that are discarded. The study consisted of the experimental deployment of a selectivity device: the use of a panel of diamond-shaped mesh netting of 70mm, in the posterior part of the purse seine, known as the "cuba de vante". As the net is pursed, the catch is concentrated near the fishing vessel and the pelagic species, along with small-sized individuals of other species are forced against the device and are thus able to pass through and escape. An 18 mm mesh cover was used to evaluate the selectivity of the by-catch reducing device. The condition and survival of fish that passed through the selectivity device were evaluated. Individuals of the main discard species were collected during normal fishing operations and maintained alive in tanks on board. After an adaptation period in 500 and 1000l tanks, contact with the selectivity device was simulated. For the sardine (Sardina pilchardus), the most important species in economic terms, stress was studied by cortisol radioimmunoassay, loss of scales and long-term mortality. The experimental fishing trial data allowed the evaluation of discards.
The main objective of this project was to evaluate the efficacy of different selectivity devices in reducing by-catch and consequently of discards in the Algarve demersal purse seine fishery.
Keywords
Purse seine;
Environmental impact;
Bycatch;
Fishing technology;
Gear selectivity;
Marine Region
38
Portuguese Waters (27.IXa,27.IXb)
1
Marine Region Map
