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The Mediterranean Sea is among the most vulnerable semi-enclosed seas to climate change. Multiple oceanic changes occur besides warming that can generate numerous ecological, social, and economic risks, challenging fisheries management at various spatial scales—from local to international. In this study, we applied a semi-quantitative climate risk assessment (CRA) to the Mediterranean small pelagic and demersal fisheries in relation to a diversity of climate-related drivers and impacts. We assessed the risks of climate change effects on demersal and small pelagic fisheries resources, fishing operations, livelihoods, and wider social and economic implications in seven sub-regions of the Mediterranean Sea. Ocean warming, an increase in extreme weather events, and changes in vertical stratification resulted in the most important climate drivers. Overall, climate drivers present higher risks to fishing resources and livelihoods than to fishing operations and wider social and economic impacts. The study puts into evidence geographic differences in terms of the drivers and impacts, with the south-eastern Mediterranean being the sub-region with higher risk levels for both fisheries, while the north-central Mediterranean also showed important risk levels for the demersal fisheries. The study furthermore discusses the most plausible adaptive measures in management, policy, research, and livelihoods to be potentially applied to address high priority risks, as well as various implementation concerns and technical effectiveness issues. Enhancing adaptive fisheries management needs to be the primary strategy for this region to reverse the high number of overfished stocks and build resilience to climate change.

At present, the assessment and management of Adriatic Sea fishery resources are based on data that do not fully account for the complex spatial patterns arising from fleet behavior and/or species' behavior and biology, mainly because logbooks do not guarantee adequate coverage of the fishing activity exerted by the fleet. For data collection, the Adriatic Sea is divided into two management areas (namely {FAO} Geographical Sub-Areas-GSAs). To account for these spatial patterns while using the data available, we propose a method for estimating the monthly landings of Italian trawlers operating in the Adriatic Sea at a higher spatial resolution than the GSA. We use a stepwise approach based on the combined analysis of questionnaire-derived vessel-specific landings and the spatial activity of the vessels with respect to a set of fishing grounds. Thus, we sequentially 1) analyze the available vessel monitoring system data, 2) partition the study area into fishing grounds (the origin of the landings), 3) cross analyze vessel-specific fishing efforts with the available vessel-specific monthly landings to estimate the {LPUE} of each fishing ground, and 4) estimate the monthly landings (by vessel, fishing ground, and harbor) for the whole fleet and the monthly fluxes between fishing grounds (origin) and landing harbors (the destination of the landings). We apply the method to two species: the Norway lobster and the European hake. For both species, we find a few fishing grounds to be consistently more productive than others and the landings per harbor to vary greatly but with few harbors regularly receiving a significant share. In particular, the results suggest that the Pomo/Jabuka pit area represents a critical area for both species. Additional outcomes include a detailed characterization of the activity of the Adriatic bottom trawling fleet, highlighting the strengths and shortcomings of the official data available. We discuss the results in the context of the current management paradigm.

The article reviews the most recent findings on the interdisciplinary characteristics of the Mediterranean Sea shelf areas, from the Northern to the southern shelf regions. First of all a classification of the shelves is carried out in terms of shelf extension, sedimentary and physical flow field properties. Secondly, the ecosystem functioning in the pelagic compartment is described as a function of the hydrodynamic regimes, as well as in relationship to land derived river inputs, if present.

Allozyme electrophoresis and morphometric analyses were used to investigate the stock structure of European anchovies (Engraulis encrasicolus L.) captured by Italian vessels in the Adriatic Sea. Twenty four putative enzyme loci were studied, all of which exhibited genotypic proportions in accordance with Hardy-Weinberg predictions. Two loci, IDHP-2 * (isocitrate dehydrogenase, 1.1.1.42) and G3PDH-2 * (glycerol-3-phosphate dehydrogenase, 1.1.1.8), showed significant allele-frequency differences among samples. IDHP-2 * 100 frequencies ranged between 0.35 and 0.88, with lower frequencies recorded in northern waters and areas close to the Italian coastline, while G3PDH-2 * 100 frequencies followed a similar, if less distinct, pattern. For both loci, the trends observed were spatially stable over a 2 yr sampling period. A putative stock-boundary was superimposed onto a map of IDHP-2 * 100 frequencies, and a bootstrapped dendrogram confirmed the genetic separation of the two putative stocks, one located around the north-western Adriatic and the other in the central-southern region. Canonical variate analysis (CVA) of morphometric data collected using a “truss network” indicated that the two putative stocks were morphologically distinct; 89.6 and 88.3% of north-western and central-southern anchovies, respectively, were correctly assigned by discriminant-function analysis. This variation may be related to the presence of two anchovy colour phenotypes, silver and blue, in the Adriatic Sea. Silver anchovies are characteristic of northern areas, while the larger blue fish are found mainly in the deeper southern waters. Current assessment models for the fishery are based on the concept of a consistent identity between consecutive catches at single ports, which our data reject. We discuss the possibility of partitioning fishing effort based on the proportions of the two stocks landed at individual ports.

Ontogenetic variation in the diet of Engraulis encrasicolus (L.) was examined in the northern Adriatic Sea, off the River Po delta, by stomach contents analysis. Anchovy (10 to 130 mm to- tal length) were collected during a 1 wk cruise in October 2002. Feeding activity was mainly diurnal in all the length classes: stomach fullness, calculated for each 10 mm size class, was always higher during the day than at night, with maximal values measured for the 40 to 49 and 50 to 59 mm size classes. All analysed life stages of E. encrasicolus had a strictly zooplanktivorous diet based on a few species of copepods. The principal prey of E. encrasicolus were small-sized copepods, measuring about 0.2 to 0.3 or 0.5 to 0.6 mm in prosoma length. The copepods Euterpina acutifrons and Oncaea spp. dominated anchovy diet during the day, both in terms of frequency, number and biomass, in all anchovy size classes. During the night, bivalve larvae were also important dietary items, with Oncaea spp. and E. acutifrons making up >69% of total prey number for all anchovy size classes. Within the considered size range, the dimensions of particles does not seem to be a limiting factor in food selection, and no re- lationship was found between anchovy length and the maximal dimension of ingested prey. Ivlev's electivity index confirmed that European anchovy was able to select specific food items and preferred small copepods such as E. acutifrons and Oncaea spp., and bivalve and decapod larvae.

The three-dimensional (3-D) shape and density distribution of a cod otolith was determined using a newly developed micro X-ray tomograph. The technique requires no special treatment of the otolith and could yield the entire 3-D growth history in a single analysis. 999 The Fisheries Society of the British Isles

The growth of two commercially important flatfish. turbot (Psetta maxima) (L.) and brill (Scophthalmus rhombus) (L.), was investigated in the Adriatic using whole otoliths (sagittae) and stained otolith sections. At variance with the pattern usually observed in temperate seas, the opaque zone was found to be laid down in autumn and winter. and the translucent zone in spring and summer. Growth rates differed according to sex. with the females attaining greater body lengths. The von Bertalanffy growth parameters were: L(infinity) = 66.2 cm, K = 0.31 years (1), and t(0) = - 0.14 years for turbot males. L(infinity) = 81.5 cm, K = 0.21 years(-1), and t(0) = -0.48 years for turbot females: L(infinity) = 40.2 cm. K = 0.49 years(-1), and t(0) = 1.03 years for brill males: L(infinity) = 50.1 cm, K = 0.27 years(-1), and t(0) = - 1.75 years for brill females. Growth rates and maximum age recorded for turbot were comparable to those reported in the North Sea.

During early development, the left and right sagittae of European hake Merluccius merluccius showed dimorphism in both size and shape due to the different number and size of accessory primordia. Juvenile hake reached the total length (L(T)) of 15 cm in c. 1 year, with monthly growth rates ranging from 1·6 cm month-1 in the third month of life to 1·1 cm month-1 towards the end of the first year. Back-calculated hatch-date distribution indicated continuous spawning with a peak in summer and a second, less evident, peak in February-March. The presence of early demersal juveniles (16-30 mm L(T), c. 40 days old) very close to the Pomo pit area (Central Adriatic Sea) at c. 140 m depths indicates that the change from the pelagic to the demersal phase takes place at c. 40 days close to the area of concentration of juveniles. The daily-increment hypothesis was validated indirectly. (C) 2000 The Fisheries Society of the British Isles., This study was partially supported by the European Union (contract XIV/C/1 MED 1991/003) and by a bilateral agreement between Consiglio Nazionale delle Ricerche (Italy) and Consejo Superior de Investigationes Cientificas (Spain).

Lo studio sulle attività alieutiche nei secoli dell'età moderna consente di ricostruire una specifica storia del Mediterraneo che trova nel Cinquecento un'epoca di transizione tra antiche e nuove maniere di pescare. La ricerca sulle fonti archivistiche ha restituito un quadro assai efficace dell'evoluzione della pesca dal XVI al XIX secolo che permette di seguire il passaggio dalla pratiche piscatorie svolte prevalentemente in prossimità della costa, a tecniche di pesca a strascico in alto mare esercitate con l'ausilio di tipi navali e attrezzature fino a quel momento mai sperimentati. L'aumento della produzione sollecita anche una migliore organizzazione dello smercio del pesce con l'utilizzo di ghiaccio per bloccare il facile deperimento del prodotto (conserve, neviere) e favorirne il trasporto sulle lunghe distanze. Nonostante le non poche problematiche sociali e organizzative del settore si avvia la trasformazione del commercio ittico che porta fra Sette e Novecento, in virtù del significativo allargamento della rete distributiva del prodotto fresco, anche un radicale cambiamento nelle abitudini alimentari.