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Marine protected areas (MPAs) are a conservation tool that are increasingly commonplace around the world. MPAs have the potential to benefit both ecosystems and human communities if well-designed and implemented. Achieving effective implementation and governance of MPAs, however, is complicated because they deal with systems that overlap with both non-human environments and human economies and societies. As a result, MPA success is thought to be primarily dependent on socioeconomic factors, particularly the behavior of stakeholder groups involved in the MPAs. Using the theory of relational coordination, we designed surveys that we delivered to members of four stakeholder groups implicated in five MPAs in the Spanish Mediterranean to investigate their habits of inter- and intra-group communication and relations. Relational coordination posits that high-quality communication and relations results in positive stakeholder behaviors and an effective system, which makes it a useful tool to investigate the effectiveness of the MPAs involved in this study. Our results demonstrate that a high degree of relational coordination leads to higher satisfaction on the part of the participants in the system. The exploratory model constructed here also supports the notion that each stakeholder group adopts particular beliefs and behaves in particular ways in terms of relational coordination and satisfaction. We found patterns that indicated poor communication and relations amongst the four stakeholder groups, which in turn has grave implications for management outcomes of these MPAs. Cumulatively, these conditions could precipitate management failure. To remedy these concerns, we recommend establishing channels of communication between the four stakeholder groups, and investigating means to cultivate good relations amongst these groups. Doing so will help assure management success.
Austin Miles; José Manuel Perea Muñoz; Just Tomàs Bayle-Sempere. Low satisfaction and failed relational coordination among relevant stakeholders in Spanish Mediterranean marine protected areas. Journal of Environmental Management 2020, 272, 111003 .
AMA StyleAustin Miles, José Manuel Perea Muñoz, Just Tomàs Bayle-Sempere. Low satisfaction and failed relational coordination among relevant stakeholders in Spanish Mediterranean marine protected areas. Journal of Environmental Management. 2020; 272 ():111003.
Chicago/Turabian StyleAustin Miles; José Manuel Perea Muñoz; Just Tomàs Bayle-Sempere. 2020. "Low satisfaction and failed relational coordination among relevant stakeholders in Spanish Mediterranean marine protected areas." Journal of Environmental Management 272, no. : 111003.
We assess the impact of recreational boat traffic on sensitive habitats in the Western Mediterranean using passive acoustics. We compared underwater sounds in three regulated mooring locations vs a pristine location; and temporal differences in the pristine location vs the nearest mooring between high and low touristic seasons. We measured the number of pulses/minute, fish pulse patterns, and percentage of boat noise occurrence and its relative average power level. At the pristine location, the call rates and their complexity were significantly higher and the motorboat noise was significantly lower. The temporal trend of biophonic sounds decreased significantly in the pristine location. In contrast, in the mooring sites, the motorboat noise decreased significantly and the fish calls remained at low levels in both seasons. In conclusion, motorboat noise negatively affects the complexity of the fish assemblages but could be conditioned to their historic uses.
José Miguel González Correa; Just-Tomás Bayle Sempere; Francis Juanes; Rodney Rountree; Juan Francisco Ruíz; Jaime Ramis. Recreational boat traffic effects on fish assemblages: First evidence of detrimental consequences at regulated mooring zones in sensitive marine areas detected by passive acoustics. Ocean & Coastal Management 2018, 168, 22 -34.
AMA StyleJosé Miguel González Correa, Just-Tomás Bayle Sempere, Francis Juanes, Rodney Rountree, Juan Francisco Ruíz, Jaime Ramis. Recreational boat traffic effects on fish assemblages: First evidence of detrimental consequences at regulated mooring zones in sensitive marine areas detected by passive acoustics. Ocean & Coastal Management. 2018; 168 ():22-34.
Chicago/Turabian StyleJosé Miguel González Correa; Just-Tomás Bayle Sempere; Francis Juanes; Rodney Rountree; Juan Francisco Ruíz; Jaime Ramis. 2018. "Recreational boat traffic effects on fish assemblages: First evidence of detrimental consequences at regulated mooring zones in sensitive marine areas detected by passive acoustics." Ocean & Coastal Management 168, no. : 22-34.
Gilthead sea bream (Sparus aurata L.) aquaculture has rapidly spread around the Mediterranean Sea. Fish escapes from sea cages are one of the major problems for the industry and also represent a threat to the marine environment. Fishery catches are also influenced by escape events, being mirrored in increased landings of cultured species. However, within the Mediterranean, studies shedding light on the incidence of escaped individuals in fisheries landings are scarce. Firstly, the present study describes a simple scale-examination methodology to distinguish escaped from wild S. aurata landed by coastal fisheries. Secondarily, the incidence of escapees is assessed within landings of the species in the western Mediterranean. The scale readings revealed a monthly incidence of escapees between 11.2 and 20.8%, representing 6.8% of the total income derived from these landings. Moreover, morphological differences between wild fish captured near and far from fish farms point towards escape events as a source of potential genetic admixture between cultured and wild genotypes. Socio-economic and ecological implications of escapees are discussed, and a set of management guidelines proposed, to prevent and/or mitigate the negative influences of escaped fish on the ecosystem and traditional users of the coast such as fisheries.
D. Izquierdo-Gómez; P. Arechavala-Lopez; Just T. Bayle-Sempere; Pablo Sanchez-Jerez. Assessing the influence of gilthead sea bream escapees in landings of Mediterranean fisheries through a scale-based methodology. Fisheries Management and Ecology 2017, 24, 62 -72.
AMA StyleD. Izquierdo-Gómez, P. Arechavala-Lopez, Just T. Bayle-Sempere, Pablo Sanchez-Jerez. Assessing the influence of gilthead sea bream escapees in landings of Mediterranean fisheries through a scale-based methodology. Fisheries Management and Ecology. 2017; 24 (1):62-72.
Chicago/Turabian StyleD. Izquierdo-Gómez; P. Arechavala-Lopez; Just T. Bayle-Sempere; Pablo Sanchez-Jerez. 2017. "Assessing the influence of gilthead sea bream escapees in landings of Mediterranean fisheries through a scale-based methodology." Fisheries Management and Ecology 24, no. 1: 62-72.
Coastal ecosystems put up a number of impacts from human activities in the sea; the most recent is fish farming, interacting synergistically with the other impacts and with the natural structure and dynamics of the coastal ecosystem. In the Mediterranean Sea, the number of fish farms has increased dramatically from early ‘80s in coastal waters, releasing a substantial amount of organic matter, modifying the habitat and communities beneath cages and changing the spatio-temporal distribution of species. Among all the effects derived from fish farming, escape events of cultured fish are a relevant issue for management given their potential impact over wild counterparts in terms of habitat and food competition, genetic flow, biodiversity, spread diseases or parasites, and interaction with local fisheries, decreasing the price of the catches. This paper shows the first approach to model the temporal trends of biomass and yields of escapes from aquaculture by means of an EwE model. Three levels of escapes (×1, ordinary level: 5000 ind year−1 fish farm−1, corresponding to 1.31 t year−1; massive event: ordinary level × 91; total destruction of fish farm: ordinary level × 1800) and four levels of fishing effort (ordinary E, ×2, ×5, ×10) were modelled as mechanism to recapture escapees. Temporal variation of biomass and yield is used to define how long should be maintained the effort to catch escapees. The total destruction of a fish farm generates the higher increase of escapees' landings, dissapearing in less than 6 months if fishing effort reach 10-fold the ordinary fishing effort. Differences among revenues from recaptures and derived expenses were always negative but tending to be greater for low levels of fishing effort and/or levels of escapes which means no fishery can be expected to be maintained by escapes. In general, fleets benefit from escapees in terms of yield but gains will depend on how escapees affect either positively or negatively the value of the catch. Simulations using EwE models may result a useful tool to design suitable recapture plans of escapees.
David Izquierdo-Gomez; Just T. Bayle-Sempere; Francisco Arreguín-Sánchez; Pablo Sanchez-Jerez. Modeling population dynamics and small-scale fisheries yields of fish farming escapes in Mediterranean coastal areas. Ecological Modelling 2016, 331, 56 -67.
AMA StyleDavid Izquierdo-Gomez, Just T. Bayle-Sempere, Francisco Arreguín-Sánchez, Pablo Sanchez-Jerez. Modeling population dynamics and small-scale fisheries yields of fish farming escapes in Mediterranean coastal areas. Ecological Modelling. 2016; 331 ():56-67.
Chicago/Turabian StyleDavid Izquierdo-Gomez; Just T. Bayle-Sempere; Francisco Arreguín-Sánchez; Pablo Sanchez-Jerez. 2016. "Modeling population dynamics and small-scale fisheries yields of fish farming escapes in Mediterranean coastal areas." Ecological Modelling 331, no. : 56-67.
David Izquierdo Gomez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; N.J. Loader; C. García De Leániz. Effects of coastal fish farms on body size and isotope composition of wild penaeid prawn. Fisheries Research 2015, 172, 50 -56.
AMA StyleDavid Izquierdo Gomez, Pablo Sanchez-Jerez, Just T. Bayle-Sempere, N.J. Loader, C. García De Leániz. Effects of coastal fish farms on body size and isotope composition of wild penaeid prawn. Fisheries Research. 2015; 172 ():50-56.
Chicago/Turabian StyleDavid Izquierdo Gomez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; N.J. Loader; C. García De Leániz. 2015. "Effects of coastal fish farms on body size and isotope composition of wild penaeid prawn." Fisheries Research 172, no. : 50-56.
Coastal fisheries and sea cage aquaculture coexist along the coastal zone, and it has been suggested that wild fish feed on excess feed around farms. If this occurs, the condition of wild fish can increase and their lipid profile can become modified. However, the influence of fishfarming on coastal fisheries has not been described in detail. Four targeted species of different trophic gilds, Sardinella aurita, Caranx rhonchus, Mullus barbatus, and Pomatomus saltatrix were studied and the lipid profiles of individuals captured by coastal fisheries and around fish farms were compared. Results show that fish captured at farms showed increased levels of total lipids and/or the terrestrial fatty acids contained in feed pellets. Individuals with increased terrestrial fatty acid proportions were detected in the catch of small-scale artisanal fisheries but not among trawled fish. Consequently, this study demonstrates the influence of fishfarming on coastal fisheries through the exportation of excess feed in the shape of wild fish biomass.
David Izquierdo-Gómez; Daniel González-Silvera; Pablo Arechavala-López; José Ángel López-Jiménez; Just T. Bayle-Sempere; Pablo Sánchez-Jerez. Exportation of excess feed from Mediterranean fish farms to local fisheries through different targeted fish species. ICES Journal of Marine Science 2014, 72, 930 -938.
AMA StyleDavid Izquierdo-Gómez, Daniel González-Silvera, Pablo Arechavala-López, José Ángel López-Jiménez, Just T. Bayle-Sempere, Pablo Sánchez-Jerez. Exportation of excess feed from Mediterranean fish farms to local fisheries through different targeted fish species. ICES Journal of Marine Science. 2014; 72 (3):930-938.
Chicago/Turabian StyleDavid Izquierdo-Gómez; Daniel González-Silvera; Pablo Arechavala-López; José Ángel López-Jiménez; Just T. Bayle-Sempere; Pablo Sánchez-Jerez. 2014. "Exportation of excess feed from Mediterranean fish farms to local fisheries through different targeted fish species." ICES Journal of Marine Science 72, no. 3: 930-938.
Groupers species are extremely vulnerable to overfishing and many species are threatened worldwide. In recent decades, Mediterranean groupers experienced dramatic population declines. Marine protected areas (MPAs) can protect populations inside their boundaries and provide individuals to adjacent fishing areas through the process of spillover and larval export. This study aims to evaluate the effectiveness of six marine reserves in the Western Mediterranean Sea to protect the populations of three species of grouper, Epinephelus marginatus, Epinephelus costae and Mycteroperca rubra, and to understand in which circumstances MPAs are able to export biomass to neighbouring areas. All the studied MPAs, except one where no grouper was observed, were able to maintain high abundance, biomass and mean weight of groupers. Size classes were more evenly distributed inside than outside MPAs. In two reserves, biomass gradients could be detected through the boundaries of the reserve as an indication of spillover. In some cases, habitat structure appeared to exert a great influence on grouper abundance, biomass and mean individual weight, influencing the gradient shape. Because groupers are generally sedentary animals with a small home range, we suggest that biomass gradients could only occur where groupers attain sufficient abundance inside MPA limits, indicating a strongly density-dependent process.
Carlos Werner Hackradt; José Antonio García-Charton; Mireille Harmelin-Vivien; Angel Pérez-Ruzafa; Laurence Le Diréach; Just Bayle-Sempere; Eric Charbonnel; Denis Ody; Olga Reñones; Pablo Sanchez-Jerez; Carlos Valle. Response of Rocky Reef Top Predators (Serranidae: Epinephelinae) in and Around Marine Protected Areas in the Western Mediterranean Sea. PLoS ONE 2014, 9, e98206 .
AMA StyleCarlos Werner Hackradt, José Antonio García-Charton, Mireille Harmelin-Vivien, Angel Pérez-Ruzafa, Laurence Le Diréach, Just Bayle-Sempere, Eric Charbonnel, Denis Ody, Olga Reñones, Pablo Sanchez-Jerez, Carlos Valle. Response of Rocky Reef Top Predators (Serranidae: Epinephelinae) in and Around Marine Protected Areas in the Western Mediterranean Sea. PLoS ONE. 2014; 9 (6):e98206.
Chicago/Turabian StyleCarlos Werner Hackradt; José Antonio García-Charton; Mireille Harmelin-Vivien; Angel Pérez-Ruzafa; Laurence Le Diréach; Just Bayle-Sempere; Eric Charbonnel; Denis Ody; Olga Reñones; Pablo Sanchez-Jerez; Carlos Valle. 2014. "Response of Rocky Reef Top Predators (Serranidae: Epinephelinae) in and Around Marine Protected Areas in the Western Mediterranean Sea." PLoS ONE 9, no. 6: e98206.
The study was financed by the EU-project “Prevent Escape” (Project Nr: 226885 http://www.preventescape.eu/)
P. Arechavala-Lopez; D. Izquierdo-Gomez; P. Sanchez‐Jerez; J. T. Bayle‐Sempere. Simulating escapes of farmed sea bass from Mediterranean open sea-cages: low recaptures by local fishermen. Journal of Applied Ichthyology 2013, 30, 185 -188.
AMA StyleP. Arechavala-Lopez, D. Izquierdo-Gomez, P. Sanchez‐Jerez, J. T. Bayle‐Sempere. Simulating escapes of farmed sea bass from Mediterranean open sea-cages: low recaptures by local fishermen. Journal of Applied Ichthyology. 2013; 30 (1):185-188.
Chicago/Turabian StyleP. Arechavala-Lopez; D. Izquierdo-Gomez; P. Sanchez‐Jerez; J. T. Bayle‐Sempere. 2013. "Simulating escapes of farmed sea bass from Mediterranean open sea-cages: low recaptures by local fishermen." Journal of Applied Ichthyology 30, no. 1: 185-188.
El cultivo de peces en mar abierto La piscicultura en mar abierto en la actividad económica que más ha crecido durante los últimos años entre las industrias marítimas y con perspectivas de seguir creciendo al mismo ritmo durante los próximos 10 años, hasta suplir las 23 millones de toneladas de pescado necesarias para mantener el nivel de consumo actual de pescado durante los próximos 20 años (FAO, 2012). España produjo en 2011 algo más de 42.000 toneladas de peces de crianza, con un valor total de 246.133.020 euros (APROMAR, 2012). Para ello se consumieron un total de 89.900 toneladas de pienso, materia orgánica que en una parte importante entra a formar parte del ecosistema marino. La piscicultura en mar abierto se desarrolla tanto en latitudes frías como tropicales, normalmente en zonas costeras ya de por sí ocupadas por otras actividades humanas, lo que supone una presión más sobre el ambiente marino litoral. La piscicultura en mar abierto genera, desde el punto de vista ecológico, varios procesos. En primer lugar, supone la creación de una estructura artificial que modifica el espacio y favorece la generación de recursos ecológicos (inicialmente espacio que aporta refugio, referencia espacial, alimento, etc; Dempster y Taquet, 2004) que atraen y agregan diferentes tipos de especies. Por otra parte, genera una cantidad de nutrientes importante tanto en forma de pienso como de materia orgánica, que desencadenan efectos en bentos, plancton y necton asociados a las piscifactorías (ver Cromey y Black, 2005, para una revisión). Los efectos pueden transcender fuera de los límites de la piscifactoría, ya sea a través del movimiento de los peces salvajes agregados que ingieren parte del pienso y contribuyen a incrementar la dispersión de los aportes de nitrógeno y compuestos orgánicos en la columna de agua (Fernández-Jover et al., 2007), variando la composición de las capturas de la pesca comercial mediante los individuos escapados (Arechavala-López et al., 2012); o generando interacciones con otras especies (Sánchez-Jerez et al., 2008) u otras actividades (Bayle-Sempere et al., 2013). En definitiva, tenemos todo un entramado formado de elementos interconectados que interaccionan entre sí, cuya respuesta global no tienen porque estar reflejada en las respuestas parciales de cada una de las partes, y que requiere de aproximaciones analíticas que permitan obtener indicadores medibles y cuantificables que reflejen el estado de la actividad en su conjunto, y su comparación con sistemas equivalentes para conseguir una gestión óptima. La piscicultura como un sistema integrado en el ecosistema costero Las piscifactorías en mar abierto pueden verse como un sistema formado por subsistemas (p.e., comunidad bentónica) o componentes singulares (p.e., peces pelágicos) interdependientes, cuya estructura y dinámica responde a las interacciones entre todos ellos. Ciertos componentes tienen mayor significación que otros en el funcionamiento del sistema según sea su papel como procesador de materia y energía. Este sistema, además, tiene una componente humana esencial, que es la fuerza motriz que desencadena la propia existencia de la actividad y que, además, debe dar las respuestas necesarias para que los efectos sean positivos a todos los niveles. En conjunto podemos considerar que el sistema formado por la piscifactoría seguirá unos principios y tendrá ciertas propiedades generadas por la suma de sus partes y la forma en que estas se relacionan entre si, permitiendo ser descrito, modelado, analizado y comparado con otros sistemas equivalentes o similares. Este enfoque es útil porque permite abordar de forma conjunta el funcionamiento de esta actividad y huir de los sesgos generados al considerar sólo ciertas partes de manera aislada o definir grupos ecológicos de manera genérica, pudiendo adoptar plenamente el enfoque ecosistémico para la gestión de la piscicultura en mar abierto. Los modelos de masas balanceadas elaborados con Ecopath (Christensen et al., 2008) son útiles para conseguir el estudio ecosistémico de las piscifactorías. Permiten el estudio tanto de los efectos directos (entre grupos o compartimentos ecológicos vinculados directamente con la piscifactoría) como de los efectos indirectos (entre piscicultura y otras actividades humanas, o grupos ecológicos no vinculados directamente a la piscifactoría). Esto último es esencial para conseguir equilibrar objetivos ecológicos y socio-económicos dentro de unos márgenes beneficiosos para todos, y es la base para desarrollar estrategias para el desarrollo sostenible de la piscicultura en mar abierto y la gestión integrada de las zonas costeras. Por otra parte, y frente a otras opciones de modelización, Ecopath es relativamente más sencillo de aplicar y ha llegado a constituirse en un marco de trabajo lo suficientemente extendido como para ofrecer una metodología de estandarización de la modelización y sus resultados, haciendo más fácil la comparación entre piscifactorías y con otros sistemas sin requerir conocimientos de programación avanzados. El modelo de Ecopath se arma con la definición de las relaciones tróficas y el flujo de energía entre los grupos ecológicos definidos a priori. Suele incluir las principales especies -autótrofas y heterótrofas- de manera individual o agregada en grupos funcionales con un rol ecotrófico similar. El modelo asume la premisa...
Just T. Bayle-Sempere; Francisco Arreguín-Sánchez; Pablo Sanchez-Jerez; Damian Fernandez-Jover; Pablo Arechavala-Lopez; David Izquierdo Gómez. Análisis y evaluación ecosistémicos de la piscicultura marina con "Ecopath with Ecosim" (EwE). Aplicaciones de modelos ecológicos a la gestión de recursos naturales 2013, 39 -65.
AMA StyleJust T. Bayle-Sempere, Francisco Arreguín-Sánchez, Pablo Sanchez-Jerez, Damian Fernandez-Jover, Pablo Arechavala-Lopez, David Izquierdo Gómez. Análisis y evaluación ecosistémicos de la piscicultura marina con "Ecopath with Ecosim" (EwE). Aplicaciones de modelos ecológicos a la gestión de recursos naturales. 2013; ():39-65.
Chicago/Turabian StyleJust T. Bayle-Sempere; Francisco Arreguín-Sánchez; Pablo Sanchez-Jerez; Damian Fernandez-Jover; Pablo Arechavala-Lopez; David Izquierdo Gómez. 2013. "Análisis y evaluación ecosistémicos de la piscicultura marina con "Ecopath with Ecosim" (EwE)." Aplicaciones de modelos ecológicos a la gestión de recursos naturales , no. : 39-65.
Based on the fact that farmed fish experience different environments, stocking densities and feeding regimes compared with wild fish, several techniques have been developed to discriminate the wild or farmed origin of fish. These techniques quantify differences between genetics, chemical characteristics, fatty acid compositions, trace elements, pollutants, stable isotopes, morphology and organoleptic characteristics. Gilthead sea bream and European sea bass are the most important marine fish in Mediterranean aquaculture and are highly appreciated by commercial and recreational fisheries. A total of 60 studies that used techniques to discriminate farmed from wild fish for sea bream and sea bass form the basis of this review. The most common technique used differences in the lipid and fatty acid composition of fish. Many of these studies dealt with food science and product quality, rather than tracing escapees. A wide range of identification tools is useful in determining the correct origin of captures and proper labelling of marketed fish. External appearance and morphometry are useful for rapid assessments and can be achieved with high accuracy and little cost, especially for sea bream. This makes these methods suitable for detecting large and recent escape events, applicable in fisheries studies, and for ensuring that wild and farmed fish are separated in the marketplace. Techniques using differences in chemical or genetic composition are more useful for environmental monitoring, as they have higher accuracy and can detect escapees long after the escape incident. Regulatory bodies should legislate protocols that describe the technique(s) that must be applied in specific circumstances.
Pablo Arechavala-Lopez; Damian Fernandez-Jover; Kenneth D. Black; Emmanuel Ladoukakis; Just T. Bayle-Sempere; Pablo Sanchez-Jerez; Tim Dempster. Differentiating the wild or farmed origin of Mediterranean fish: a review of tools for sea bream and sea bass. Reviews in Aquaculture 2013, 5, 137 -157.
AMA StylePablo Arechavala-Lopez, Damian Fernandez-Jover, Kenneth D. Black, Emmanuel Ladoukakis, Just T. Bayle-Sempere, Pablo Sanchez-Jerez, Tim Dempster. Differentiating the wild or farmed origin of Mediterranean fish: a review of tools for sea bream and sea bass. Reviews in Aquaculture. 2013; 5 (3):137-157.
Chicago/Turabian StylePablo Arechavala-Lopez; Damian Fernandez-Jover; Kenneth D. Black; Emmanuel Ladoukakis; Just T. Bayle-Sempere; Pablo Sanchez-Jerez; Tim Dempster. 2013. "Differentiating the wild or farmed origin of Mediterranean fish: a review of tools for sea bream and sea bass." Reviews in Aquaculture 5, no. 3: 137-157.
Pablo Arechavala Lopez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; I Uglem; I Mladineo. Reared fish, farmed escapees and wild fish stocks—a triangle of pathogen transmission of concern to Mediterranean aquaculture management. Aquaculture Environment Interactions 2013, 3, 153 -161.
AMA StylePablo Arechavala Lopez, Pablo Sanchez-Jerez, Just T. Bayle-Sempere, I Uglem, I Mladineo. Reared fish, farmed escapees and wild fish stocks—a triangle of pathogen transmission of concern to Mediterranean aquaculture management. Aquaculture Environment Interactions. 2013; 3 (2):153-161.
Chicago/Turabian StylePablo Arechavala Lopez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; I Uglem; I Mladineo. 2013. "Reared fish, farmed escapees and wild fish stocks—a triangle of pathogen transmission of concern to Mediterranean aquaculture management." Aquaculture Environment Interactions 3, no. 2: 153-161.
A fish farm in Southeastern Spain was described using an Ecopath mass-balanced model, aimed at characterising its structure, the interactions among ecological groups and the impact of fish farms and fisheries. The model comprised 41 functional groups (including the artificial food input). Comparing consumption and respiration to total system throughput suggests lower energy use in the fish farm, resulting in an accumulation of detritus. The production to total system throughput ratio was low due to the low efficiency of the modelled ecosystem. The connectance and system omnivory indexes were low, typical of a simple or immature food web in terms of structure and dynamics. Artificial food pellets provided energy and nutrients to sustain system function and generate a considerable reserve from which it can draw to meet unexpected perturbations. The study shows the substantial effect the artificial food pellets have on the wild aggregated fishes, which could act to buffer the ecosystem and hence prevent environmental degradation.Conselleria d’Educació, Generalitat Valenciana. MARTORRES. The study forms part of the ACUFISH project (Department of Marine Science and Applied Biology, University of Alicante) and was funded by Spanish Ministry of Science Grant MYCT-REN2003-00794
Just T. Bayle-Sempere; Francisco Arreguín-Sánchez; Pablo Sanchez-Jerez; Luis Antonio Salcido Guevara; Damián Fernandez-Jover; Manuel J Zetina-Rejón. Trophic structure and energy fluxes around a Mediterranean fish farm. Ecological Modelling 2013, 248, 135 -147.
AMA StyleJust T. Bayle-Sempere, Francisco Arreguín-Sánchez, Pablo Sanchez-Jerez, Luis Antonio Salcido Guevara, Damián Fernandez-Jover, Manuel J Zetina-Rejón. Trophic structure and energy fluxes around a Mediterranean fish farm. Ecological Modelling. 2013; 248 ():135-147.
Chicago/Turabian StyleJust T. Bayle-Sempere; Francisco Arreguín-Sánchez; Pablo Sanchez-Jerez; Luis Antonio Salcido Guevara; Damián Fernandez-Jover; Manuel J Zetina-Rejón. 2013. "Trophic structure and energy fluxes around a Mediterranean fish farm." Ecological Modelling 248, no. : 135-147.
The present study compares fin damages in gilthead seabream (Sparus aurata) and European seabass (Dicentrarchus labrax) according to their wild, escaped or farmed origins. In addition, the potential applicability of fin condition indices (Fin Erosion Index ‘FEI’ and Fin Splitting Index ‘FSI’) as identification tools is discussed. Farmed seabream fins evidenced more erosion and splitting (FEI ± SD: 2.1 ± 0.3; FSI ± SD: 1.9 ± 0.6) than wild seabream fins (FEI: 0.8 ± 0.6; FSI: 1.2 ± 0.9), a result of farming conditions in open‐sea cages. Escaped seabream fin erosion was between that of farmed and wild seabream (FEI: 1.6 ± 0.4), which could indicate that fins in farmed fish recover over time from farming abrasions once they are in the wild. However, the fins of escaped seabream seem to be weaker than those of the wild fish, and therefore might be more susceptible to suffer other types of erosion such as splitting or nipping (FSI: 2.3 ± 0.7). No significant differences were found in seabass FEI according to their origins, although wild seabass presented significantly more split caudal fins (FSI: 3.3 ± 2.8) than the farmed seabass (FSI: 1.2 ± 1.1) and escapees (FSI: 2.5 ± 1.6). Therefore, FEI for seabream could be used as tools not only to distinguish between wild and farmed fish, but also to identify recent escapees, improving further assessments on the contribution of seabream escapees in fishery landings. However, the healing potential of damaged fins must be considered for the proper identification of escapees. Use of fin condition indices from both species could be helpful for aquaculture management, to assess fish welfare in fish farms stocks, and improve the knowledge of handling, stock densities and open‐sea cage environment conditions.
Pablo Arechavala Lopez; Pablo Sanchez-Jerez; David Izquierdo Gomez; Kilian Toledo-Guedes; Just T. Bayle-Sempere. Does fin damage allow discrimination among wild, escaped and farmed Sparus aurata (L.) and Dicentrarchus labrax (L.)? Journal of Applied Ichthyology 2012, 29, 352 -357.
AMA StylePablo Arechavala Lopez, Pablo Sanchez-Jerez, David Izquierdo Gomez, Kilian Toledo-Guedes, Just T. Bayle-Sempere. Does fin damage allow discrimination among wild, escaped and farmed Sparus aurata (L.) and Dicentrarchus labrax (L.)? Journal of Applied Ichthyology. 2012; 29 (2):352-357.
Chicago/Turabian StylePablo Arechavala Lopez; Pablo Sanchez-Jerez; David Izquierdo Gomez; Kilian Toledo-Guedes; Just T. Bayle-Sempere. 2012. "Does fin damage allow discrimination among wild, escaped and farmed Sparus aurata (L.) and Dicentrarchus labrax (L.)?" Journal of Applied Ichthyology 29, no. 2: 352-357.
Invasion of algal habitat by the alien alga Caulerpa racemosa results in changes to habitat structure, part of which may be due to accumulation of large amounts of detritus. In turn, such changes lead to alterations in the assemblage structure of associated invertebrates. The present study was aimed at testing the hypotheses that (i) invasion by C. racemosa will influence the assemblage structure of amphipods associated with vegetated habitats, since colonisation by the invertebrates will differ between native algal habitat and habitat invaded by the alien alga, and (ii) differences in colonisation are mainly due to accumulation of detritus by the alien alga. To test these hypotheses, field experiments on habitat colonisation were undertaken at two sites within each of two Mediterranean localities (Malta and Spain). Using mesh bags, 3 different habitats were introduced at each site: habitat with the native alga Halopteris scoparia, habitat with C. racemosa, and an artificial habitat resembling algal habitat. Additionally, empty mesh bags were deployed as controls. Mesh bags containing plant material were defaunated prior to deployment. For each of the three habitat types, three supplement treatments were used: (i) no detritus, (ii) low detritus, and (ii) high detritus. The bags were placed on a rocky substratum at a water depth of 4.5–5 m for a period of 14 days, after which they were collected and the amphipod assemblage was assessed. The results showed that, overall, amphipod species richness and abundance were higher in bags containing H. scoparia but some amphipods exhibited a broad capability to colonize new habitat such as C. racemosa. Accumulation of detritus by the alien alga may play an important role but small-scale physical or biological habitat features can affect its ecological role.
Maite Vázquez-Luis; Joseph A. Borg; Pablo Sanchez-Jerez; Just T. Bayle-Sempere. Habitat colonisation by amphipods: Comparison between native and alien algae. Journal of Experimental Marine Biology and Ecology 2012, 432-433, 162 -170.
AMA StyleMaite Vázquez-Luis, Joseph A. Borg, Pablo Sanchez-Jerez, Just T. Bayle-Sempere. Habitat colonisation by amphipods: Comparison between native and alien algae. Journal of Experimental Marine Biology and Ecology. 2012; 432-433 ():162-170.
Chicago/Turabian StyleMaite Vázquez-Luis; Joseph A. Borg; Pablo Sanchez-Jerez; Just T. Bayle-Sempere. 2012. "Habitat colonisation by amphipods: Comparison between native and alien algae." Journal of Experimental Marine Biology and Ecology 432-433, no. : 162-170.
Escapes of cultured gilthead seabream (Sparus aurata L.) have been recorded throughout the Mediterranean Sea. In the current study we simulated escape incidents of seabream tagged with acoustic transmitters (N = 38) or external tags (N = 2191). Tagged individuals showed both a high dispersion within the first 5 days after release and a high mortality rate (>60%) where the fish appeared to be predated at the release farm. However, some individuals remained not only at the release farm but also at the nearby farm facilities for long periods, surviving up to 4 weeks with a clear diurnal swimming depth behaviour related to farm activity. Local fisheries contributed largely recapturing tagged individuals that disperse from farm facilities (7.25%), being professional trammel-netters the major contributors (71.5%). Those recaptured individuals were caught on usual fishing grounds and habitats where their wild conspecific live (seagrass, sand or rocky bottoms), feeding on natural preys such as crustaceans and molluscs after one week in the wildness. Therefore, our findings emphasize the negative ecological consequences that escapees might entail to nearby cultured and wild stocks, and the importance of local fisheries to reduce the potential effects of escape incidents on natural stocks.
Pablo Arechavala Lopez; I. Uglem; Damian Fernandez-Jover; Just T. Bayle-Sempere; Pablo Sanchez-Jerez. Post-escape dispersion of farmed seabream (Sparus aurata L.) and recaptures by local fisheries in the Western Mediterranean Sea. Fisheries Research 2012, 121-122, 126 -135.
AMA StylePablo Arechavala Lopez, I. Uglem, Damian Fernandez-Jover, Just T. Bayle-Sempere, Pablo Sanchez-Jerez. Post-escape dispersion of farmed seabream (Sparus aurata L.) and recaptures by local fisheries in the Western Mediterranean Sea. Fisheries Research. 2012; 121-122 ():126-135.
Chicago/Turabian StylePablo Arechavala Lopez; I. Uglem; Damian Fernandez-Jover; Just T. Bayle-Sempere; Pablo Sanchez-Jerez. 2012. "Post-escape dispersion of farmed seabream (Sparus aurata L.) and recaptures by local fisheries in the Western Mediterranean Sea." Fisheries Research 121-122, no. : 126-135.
Ecological interactions involving introduced seaweeds constitute an important research gap, since they could alter the trophic dynamics of native populations, but indirect effects on trophic levels are poorly known. The seaweedCaulerpa racemosais one of the most notable invaders in the Mediterranean Sea. It is well known thatC. racemosamodifies the amphipod community with respect to native habitats, but nothing is known regarding the common use of the same trophic resources. Therefore, the aim of this study was to assess if the feeding habits of amphipods associated with algal habitats are affected by the spread of the invasiveC. racemosa, through stomach content analysis of amphipods living in both native and invaded seaweed assemblages. A total of 240 specimens of 14 species of amphipods were examined. Ten species were present in both studied habitats (native and invaded), while two were exclusive to native and invaded habitats, respectively. Ten individuals of each species at each habitat were selected and their gut contents were examined. A total of 11 different items was found in the gut contents: detritus; vegetal detritus; algae; animal tissue; Oligochaeta; Polychaeta; Foraminifera; Crustacea; Sipuncula; diatoms; and non-identified items. The expansion ofC. racemosainto the native algal community changes the feeding habits of herbivorous amphipods, since their preferred food (epiphytic algae) is not available in the new habitat produced byC. racemosa. This community change occurs because of the presence of caulerpenyne inC. racemosa, which retards the growth of epiphytic algae. Nevertheless, other species are not affected or benefited by the invasion, such as detritivorous species whose main food source and habitat remains available. Altogether, slight changes in the trophodynamism of amphipod assemblages have been detected, which are not seen as relevant in an initial stage. However, they might be promoting some indirect effects in the energetic budget of populations, which may affect the life history. Further studies on food-web interactions in the ecosystems affected by invasive species are necessary.
Maite Vázquez-Luis; Pablo Sanchez-Jerez; Just T. Bayle-Sempere. Does the invasion ofCaulerpa racemosavar.cylindraceaaffect the feeding habits of amphipods (Crustacea: Amphipoda)? Journal of the Marine Biological Association of the United Kingdom 2012, 93, 87 -94.
AMA StyleMaite Vázquez-Luis, Pablo Sanchez-Jerez, Just T. Bayle-Sempere. Does the invasion ofCaulerpa racemosavar.cylindraceaaffect the feeding habits of amphipods (Crustacea: Amphipoda)? Journal of the Marine Biological Association of the United Kingdom. 2012; 93 (1):87-94.
Chicago/Turabian StyleMaite Vázquez-Luis; Pablo Sanchez-Jerez; Just T. Bayle-Sempere. 2012. "Does the invasion ofCaulerpa racemosavar.cylindraceaaffect the feeding habits of amphipods (Crustacea: Amphipoda)?" Journal of the Marine Biological Association of the United Kingdom 93, no. 1: 87-94.
The study of mass and standard length (LS) relationships showed that farmed individuals had higher values than wild fishes for both gilthead sea bream Sparus aurata and European sea bass Dicentrarchus labrax. Such differences were more pronounced in larger individuals than smaller ones and were more noticeable in S. aurata than in D. labrax. Additionally, differences in external characteristics of scales were detected between origins. A high proportion of farmed S. aurata had a regenerated nucleus (98%) and scale malformations (73%), and there were no annual rings in the farmed D. labrax (100%). Variation in otolith morphology was examined through shape descriptors such as area, perimeter, circularity, roundness, mass, height and length relationship and elliptic Fourier descriptors (EFDs). Important differences were found within geographical origins according to each shape descriptor separately, but no clear patterns distinguished wild and farmed fish. Discriminant analysis with either all shape descriptors together or EFDs was able to classify with high accuracy both S. aurata (89·5–95·7%) and D. labrax (93·2–95·2%) according to their origin. Hence, this study suggests the use of scale characteristics as the easiest and quickest way to distinguish farmed or escaped fishes, and secondly, the usefulness of EFDs or shape descriptors to improve such separation.
P. Arechavala-Lopez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; D. G. Sfakianakis; S. Somarakis. Discriminating farmed gilthead sea bream Sparus aurata and European sea bass Dicentrarchus labrax from wild stocks through scales and otoliths. Journal of Fish Biology 2012, 80, 2159 -2175.
AMA StyleP. Arechavala-Lopez, Pablo Sanchez-Jerez, Just T. Bayle-Sempere, D. G. Sfakianakis, S. Somarakis. Discriminating farmed gilthead sea bream Sparus aurata and European sea bass Dicentrarchus labrax from wild stocks through scales and otoliths. Journal of Fish Biology. 2012; 80 (6):2159-2175.
Chicago/Turabian StyleP. Arechavala-Lopez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; D. G. Sfakianakis; S. Somarakis. 2012. "Discriminating farmed gilthead sea bream Sparus aurata and European sea bass Dicentrarchus labrax from wild stocks through scales and otoliths." Journal of Fish Biology 80, no. 6: 2159-2175.
Gilthead seabream (Sparus aurata L.) and European seabass (Dicentrarchus labrax L.) are important commercial marine fish species both for aquaculture and fisheries in the Mediterranean. It is known that farmed individuals escape from farm facilities, but the extent of escape events is not easy to report and estimate because of the difficulty to distinguish between wild and farmed individuals. In this study, significant differences provided through morphometry evidence that the cranial and body regions of seabream and seabass are different regarding their farm or wild origin at different scales. Morphological variations have been shown to be a valuable tool for describing changes in shape features. Therefore, the biomass contribution of escapees to local habitats could be determined by identifying escaped individuals from fisheries landings as a first step to assess the potential negative effects of fish farm escapees on the environment, and their influence on wild stocks and local fisheries.
P. Arechavala-Lopez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; D. G. Sfakianakis; S. Somarakis. Morphological differences between wild and farmed Mediterranean fish. Hydrobiologia 2011, 679, 217 -231.
AMA StyleP. Arechavala-Lopez, Pablo Sanchez-Jerez, Just T. Bayle-Sempere, D. G. Sfakianakis, S. Somarakis. Morphological differences between wild and farmed Mediterranean fish. Hydrobiologia. 2011; 679 (1):217-231.
Chicago/Turabian StyleP. Arechavala-Lopez; Pablo Sanchez-Jerez; Just T. Bayle-Sempere; D. G. Sfakianakis; S. Somarakis. 2011. "Morphological differences between wild and farmed Mediterranean fish." Hydrobiologia 679, no. 1: 217-231.
Fatty acids (FA) have been applied as indicators of the influence of coastal sea-cage fish farming on wild fish communities in several recent scientific publications. Due to the relatively high conservation of FA composition throughout the food web, they are useful for characterizing trophic relationships. The increasing utilization of vegetable or alternative animal oils in the production of aquafeeds results in cultivated fish exhibiting higher levels of terrestrial FAs in their tissues. As previously reported, wild fish ubiquitously aggregate around fish farms as a consequence of the introduction of new habitat and the easy availability of food—fish farms act as enhanced fish aggregation devices (FADs). The influence of food pellets on the composition of wild fish has been detected in recent studies on salmon, sea bass and sea bream aquaculture, with increased levels of linoleic acid (18:2n-6) and a low n-3/n-6 ratio as clear indicators of the consumption of food pellets from the farms. The potential ecological and physiological effects on wild fish are presently unknown. In the present article, guidelines are proposed for the investigation and use of terrestrial FAs to track the effects of coastal aquaculture on wild fish communities and local fisheries, as well as the benefits or limitations of this technique.This review forms part of the FATFISH project (Dept. of Marine Sciences and Applied Biology of the University of Alicante, Dept. of Physiology of the University of Murcia and Institute of Aquaculture of the University of Stirling) and was funded by the Spanish Ministry of Science. Project Reference CTM2009-14362-CO2-01/2
D Fernandez-Jover; P Arechavala-Lopez; L Martinez-Rubio; Tocher; Just T. Bayle-Sempere; Ja Lopez-Jimenez; Fj Martinez-Lopez; Pablo Sanchez-Jerez; Douglas Tocher. Monitoring the influence of marine aquaculture on wild fish communities: benefits and limitations of fatty acid profiles. Aquaculture Environment Interactions 2011, 2, 39 -47.
AMA StyleD Fernandez-Jover, P Arechavala-Lopez, L Martinez-Rubio, Tocher, Just T. Bayle-Sempere, Ja Lopez-Jimenez, Fj Martinez-Lopez, Pablo Sanchez-Jerez, Douglas Tocher. Monitoring the influence of marine aquaculture on wild fish communities: benefits and limitations of fatty acid profiles. Aquaculture Environment Interactions. 2011; 2 (1):39-47.
Chicago/Turabian StyleD Fernandez-Jover; P Arechavala-Lopez; L Martinez-Rubio; Tocher; Just T. Bayle-Sempere; Ja Lopez-Jimenez; Fj Martinez-Lopez; Pablo Sanchez-Jerez; Douglas Tocher. 2011. "Monitoring the influence of marine aquaculture on wild fish communities: benefits and limitations of fatty acid profiles." Aquaculture Environment Interactions 2, no. 1: 39-47.
P. Arechavala-Lopez; I. Uglem; D. Fernandez-Jover; J. T. Bayle‐Sempere; P. Sanchez‐Jerez. Immediate post-escape behaviour of farmed seabass (Dicentrarchus labrax L.) in the Mediterranean Sea. Journal of Applied Ichthyology 2011, 27, 1375 -1378.
AMA StyleP. Arechavala-Lopez, I. Uglem, D. Fernandez-Jover, J. T. Bayle‐Sempere, P. Sanchez‐Jerez. Immediate post-escape behaviour of farmed seabass (Dicentrarchus labrax L.) in the Mediterranean Sea. Journal of Applied Ichthyology. 2011; 27 (6):1375-1378.
Chicago/Turabian StyleP. Arechavala-Lopez; I. Uglem; D. Fernandez-Jover; J. T. Bayle‐Sempere; P. Sanchez‐Jerez. 2011. "Immediate post-escape behaviour of farmed seabass (Dicentrarchus labrax L.) in the Mediterranean Sea." Journal of Applied Ichthyology 27, no. 6: 1375-1378.