Case Study 5.2-Trammel net fishery in Majorca Island (Western Mediterranean) Beatriz Morales Nin, IMEDEA Majorca

Majorcan small-scale fisheries The artisanal fishery represents 0.01% of the total economy of the island. The Administration considers there is no fleet overcapacity. This fishery includes 496 boats in the whole Archipelago and 164 in Majorca Island. Managed by effort control. Trammel nets are used by around 62.55% of the boats in Majorca targeting a large pool of commercial species or categories. The boats employed in this fishery correspond to group C (minor gear with engine), as defined by the Scientific Advisory Committee of the CGFM. Commercialisation on a main wharf How is the exploitation of the trammel net fishery? What determines prices? Are there better management measures? 5 years of daily sales registers by boat for the target species Personal interviews with fisherman and administrators 1year of monthly visits to the wharf for length frequency estimations of the total catch by boat

Types of fisheries and their relative importance/volume Cuttlefish trammelnet (used by 29.19% of the boats) - Used from November to July - Inner mesh size of the trammelnet between mm Red mullet trammelnet (18.18 %) - Used from June to December - Inner mesh size between mm down to 36 mm Lobster trammelnet (18.18 %) - Used from March to September - Inner mesh size of the trammelnet 133 mm Scorpaena spp is caught in the three trammelnets The species are sold in different commercial categories: small and large size m depth. 60 m depth.

RMTN is more selective for cm individuals while CTN catches a wide range of red mullet ages.

CTN catches mainly 9-13 cm individuals. RMTN almost does not fish cuttlefish,

The red mullet trammel net (RMTN) fishes younger S.scrofa and older S.porcus but less individuals than the cutlefish net (CTN)

Current knowledge of the 4 analyzed species (landings and effort data; priors) was used in Bayesian surplus production models (Meyer and Millar, 1999) with no satisfactory results. Thus, a simple production function was used to approach the case study. The parameter estimation of Schaefer’s model was carried out with CEDA 3.0 (Kirkwood et al., 2001). The results of the parameter estimation, the fitted models, and the relation between observations and estimated equilibrium curves showed an exploitation near MSY status for the main species analyzed (black scorpionfish, red scorpionfish, red mullet and cuttlefish). A short time series can be used in surplus production estimation when there are not big changes in the fishery and the effort is directed to target species. Production model

Blue point data for 2006 used for model validation r = 0.36; K = ; q = ; B(2002)/K = 0.5

r = 1.056; K = ; q = ; B(2002)/K = 0.5

r = 0.5; K = ; q = ; B(2002)/K = 0.5

daily sales registers 2006 sales registers and length composition Annual offer and demand Seasonal variation in price and mean length Catch-price trends Monthly catch and price trends Prices

Red mullet Mullus surmuletus

Red mullet Mullus surmuletus

Cutlefish Sepia officinalis

Cutlefish Sepia officinalis

Black scorpionfish Scorpaena scrofa

Black scorpionfish Scorpaena scrofa

Red scorpionfish Scorpaena porcus Red scorpionfish Scorpaena porcus

Red scorpionfish Scorpaena porcus

Interviews I. Vessels technical characteristics: Overall length, TRB (or GT), crew size. II. Fishing tactics. 1) Type of trammel net used and season. 2) Landings of black and red scorpionfish associated to the trammel nets used. 3) Targeted secondary species. III. Socioeconomics: 1) Hours working in the sea and in the harbour. 2) Fuel consumption. 3) Cost and durability of a trammel net, manufactured or home made, origin. 4) Equipment investments, engine renewal. IV. Commercialization and management. 1) Price formation, key factors determining products’ selling price. 2) Which management actions would a fisher propose to improve artisanal fisheries in Majorca. 26% of the fishermen interviewed

Interviews analysis The mean crew 1.3 people artisanal vessel size 8.55 m average gross tonnage 2.88 t and TRB 5.45 t. Time working at sea 8 h+4.5 at harbour Fuel 300 l/week 40% revenues invested Fishermen complaints and suggestions for management. Vessels first number indicate their harbour (1 Alcúdia; 2 Cala Ratjada, 3 Colònia de Sant Jordi, 4 Palma, 5 Pollença and 6 Portocolom). Management options proposed by fishermen Conflicts with recreational fishing and dolphins Increase subsidies Increase effort control Improve commercialization Reduce effort for 1 day

Future developments Aim of management to improve gains Based on the commercial aspects (Fishing Wharf closed on Mondays) and the 30 h weekly consecutive closure (normally on Saturdays), one main question was raised according to fishermen’s interviews: What can be the effect of effort reduction with a weekly 48 h closure from Saturday to Monday? To be explored using MEFISTO bioeconomic model Improve the price analysis exploring the commercial categories (size effects)