PESQUERÍA DE PATUDO O TUNA (BIGEYE TUNA)

SUMMARY The main objective of this study is to carry out a detailed analysis of the bigeye tuna fishery (Thunnus obesus) in the Canary Islands during the period 1926 to 2020. The existence of this fishery dates back to the early 19th century on the island of La Gomera. Fishing effort has varied throughout the period under study. Catches of this species are analysed for the period 1965 to 2020. In the 1970s and 1990s, the maximum historical levels were reached i.e. 6,991 t and 9,325 t, respectively. The method of fishing on associated schools has modified the exploitation pattern. Catch seasonality has changed, shifting from the first and second quarters in the first period to the third and fourth quarters currently. The sizes of the catch taken on free schools and associated schools are different. In the 1980s and 1990s, the fishing areas were closer to each other. In the 2000s, the main fishing areas are located in the South, West and North of the islands, until Madeira and the Azores. RÉSUMÉ L'objectif principal de cette étude est de réaliser une analyse détaillée de la pêche du thon obèse (Thunnus obesus) dans les îles Canaries pendant la période 1926 à 2020. L'existence de cette pêche remonte au début du XIXe siècle à l'île de La Gomera. L'effort de pêche a varié tout au long de la période d'étude. Les captures de cette espèce sont analysées pour la période de 1965 à 2020. Dans les années 1970 et 1990, les niveaux historiques maximums ont été atteints avec 6.991 t et 9.325 t respectivement. La modalité de pêche sur mattes associées a modifié le schéma d'exploitation de l'espèce. La saisonnalité des captures a changé, passant du premier et deuxième trimestre de la première période au troisième et quatrième trimestre actuellement. Les tailles de capture réalisées sur bancs libres et mattes associées sont différentes. Dans les années 1980 et 1990, les zones de pêche étaient plus proches les unes des autres. Dans les années 2000, les principales zones de pêche se situent au sud, à l'ouest et au nord des îles, jusqu'à Madère et aux Açores. RESUMEN El principal objetivo de este estudio es realizar un análisis detallado de la pesquería de patudo (Thunnus obesus), también llamado tuna, en las islas Canarias, durante el período 1926 a 2020. La existencia de esta pesquería se remonta a principios del pasado siglo XIX en la isla de La Gomera. El esfuerzo pesquero ha variado a lo largo del período de estudio. Se analizan las capturas de esta especie para el período 1965 a 2020. En los 70 y 90 se produjeron los máximos históricos con 6991 t y 9325 t respectivamente. La modalidad de pesca “ a mancha” ha modificado el patrón de explotación de la especie. La estacionalidad de las capturas ha cambiado desde el primer y segundo trimestre de la primera época hacia el tercer y cuarto trimestre actualmente. Las tallas de captura son diferentes a banco libre y en mancha. En los 80 y 90 los caladeros de pesca estaban más cerca. En los 2000 las principales zonas de pesca están al sur, al oeste y al norte de las islas, llegando hasta Madeira y Azores.Versión del edito

Data Provision for Science-Based FAD Fishery Management: Spanish FAD Management Plan as a Case Study

The use of fish aggregating devices (FADs) in tropical tuna fisheries has increased significantly during recent decades. Concurrently, concern about juvenile tuna mortality, bycatch, and marine debris associated with FAD fisheries increased, and this led to the implementation of FAD management measures and more sustainable designs (e.g., non-entangling or biodegradable FADs, limits on active FADs, etc.). This document reviews data collection and reporting requirements of tuna-Regional Fisheries Management Organizations (t-RFMOs) on drifting FADs and summarizes the work carried out since 2010 under the Spanish FAD management plan to create an adequate standard data collection aimed at improving science-based decision making. The aim of this study is to assist in the strengthening of data collection systems through: (1) a review of the existing data requirements, (2) a review of the status of FAD data collection worldwide and identification of data gaps, and (3) recommendations aimed at improving FAD management through the strengthening of FAD data requirements. Due to the complexities of data collection, we summarize the difficulties faced when processing the data and propose concrete and practical solutions to improve both the data collection system and information quality.Postprin

A NOVEL INDEX OF ABUNDANCE OF JUVENILE YELLOWFIN TUNA IN THE ATLANTIC OCEAN DERIVED FROM ECHOSOUNDER BUOYS

The collaboration with the Spanish vessel-owners associations and the buoy-providers companies, has made it possible the recovery of the information recorded by the satellite linked GPS tracking echosounder buoys used by the Spanish tropical tuna purse seiners and associated fleet in the Atlantic since 2010. These instrumental buoys inform fishers remotely in real-time about the accurate geolocation of the FAD and the presence and abundance of fish aggregations underneath them. Apart from its unquestionable impact in the conception of a reliable CPUE index from the tropical purse seine tuna fisheries fishing on FADs, echosounder buoys have also the potential of being a privileged observation platform to evaluate abundances of tunas and accompanying species using catch-independent data. Current echosounder buoys provide a single acoustic value without discriminating species or size composition of the fish underneath the FAD. Therefore, it has been necessary to combine the echosounder buoys data with fishery data, species composition and average size, to obtain a specific indicator. This paper presents a novel index of abundance of juvenile yellowfin tuna in the Atlantic Ocean derived from echosounder buoys for the period 2010-2018

Biodegradable DFADs: Current status and prospects

Until recently, dFAD structure, materials and designs have remained quite rudimentary and virtually the same since their discovery, characterized by the increase of the dimensions and prevailing heavy use of plastic components. Biodegradable materials are called to be an important part of the solution, as they can faster degrade in the environment, free of toxins and heavy metals, reducing their lifespan, and preventing them from accumulating in sensitive areas once they are abandoned, lost or discarded. During last decades, regulatory measures at tRFMOs have advanced in the gradual implementation of biodegradable materials in dFAD constructions together with other measures limiting the number of active dFADs and the use of netting materials. However, more clarity is needed starting with a standardised definition of biodegradable dFADs among tRFMOs, to provide operational guidance. Research with those natural and synthetic materials is required, along with updated data collection for monitoring standards, as well as alternative and complementary actions need to be explored to contribute to minimising dFAD adverse effects on environment. Acknowledging the current difficulties for the implementation of fully biodegradable dFADs a stepwise process towards the implementation of fully biodegradable dFADs should be considered.Postprin

Best standards for data collection and reporting requirements on FOBs: towards a science-based FOB fishery management.

A major concern for tropical tunas, on these last years, has been the worldwide increasing use of drifting FOBs by purse seiners, which are equipped with satellite buoys and echo-sounders. The use of these floating objects has contributed to increase the catch of skipjack tuna, but also of juveniles of yellowfin and bigeye tunas. Moreover, it has increased the amount of by-catch (including some species classified as vulnerable or endangered) and has likely resulted in adverse effects on the ecology of fish and on vulnerable areas (e.g. beaching events on coral reef areas). Despite the increasing FOB use and concerns, little information is available on FOB use worldwide for an appropriate monitoring and management. Thus, FOB monitoring has become a priority in all tuna t-RFMOs. However, the data collection and reporting requirements around FOBs are not standardized and there are significant data gaps. The aim of this document is to review current requirements and procedures in place and propose standards for data collection and submission on FOBs to tRFMOs. The proposals included in this document are the result of a collaborative work between scientists and the fishing industry

Biodegradable drifting fish aggregating devices: Current status and future prospects

The structure, materials and designs of drifting Fish Aggregating Devices (dFADs) have generally remained rudimentary and relatively unchanged since they first came into use in the 1980 s. However, more recently, dFADs have been increasing in dimensions and the prevailing use of plastic components. Abandoned, lost or discarded dFADs can therefore contribute to the global marine litter problem. Transitioning to biodegradable and non-toxic materials that have a faster rate of decomposition, and are free of toxins and heavy metals, relative to synthetic materials, has been prescribed as an important part of the solution to reducing marine pollution from industrial tuna fisheries that rely on dFADs. This review of the current state of dFADs considers aspects related to the use of biodegradable materials in their construction, including; regulations related to dFAD materials, trials of biodegradable designs and materials and future alternatives. During the last decade, regulatory measures at tuna Regional Fishery Management Organizations (tRFMOs) have gradually moved towards the clear recommendation to use biodegradable materials in dFAD construction together with other measures limiting the number of active dFADs and the use of netting materials. However, to provide operational guidance, more clarity is needed, starting with a standardised definition of biodegradable dFADs among tRFMOs. Research involving dFAD natural and synthetic materials is required, along with improved data collection for monitoring the transition of dFAD materials against specified standards for biodegradable dFADs. In addition, alternative and complementary actions need to be explored to contribute to minimising adverse effects of dFADs on the environment. Acknowledging the current difficulties for the implementation of fully biodegradable dFADs in tuna fisheries, a stepwise process towards the implementation of commercially viable biodegradable dFADs should be considered.Peer reviewe

Large Asymmetric Hypertrophy of Rectus Abdominis Muscle in Professional Tennis Players

Purpose: To determine the volume and degree of asymmetry of the musculus rectus abdominis (RA) in professional tennis players. Methods: The volume of the RA was determined using magnetic resonance imaging (MRI) in 8 professional male tennis players and 6 non-active male control subjects. Results: Tennis players had 58 % greater RA volume than controls (P = 0.01), due to hypertrophy of both the dominant (34% greater volume, P = 0.02) and non-dominant (82 % greater volume, P = 0.01) sides, after accounting for age, the length of the RA muscle and body mass index (BMI) as covariates. In tennis players, there was a marked asymmetry in the development of the RA, which volume was 35 % greater in the non-dominant compared to the dominant side (P,0.001). In contrast, no sideto-side difference in RA volume was observed in the controls (P = 0.75). The degree of side-to-side asymmetry increased linearly from the first lumbar disc to the pubic symphysis (r = 0.97, P,0.001). Conclusions: Professional tennis is associated with marked hypertrophy of the musculus rectus abdominis, which achieves a volume that is 58 % greater than in non-active controls. Rectus abdominis hypertrophy is more marked in the non-dominant than in the dominant side, particularly in the more distal regions. Our study supports the concept that humans can differentially recruit both rectus abdominis but also the upper and lower regions of each muscle. It remains to b

Caracterización del Sur de Fuerteventura

Se integra información hidrográfica, geomorfológica, sedimentológica, biológica, sobre hábitats marinos y pesquera, para establecer las bases ecológicas necesarias para la protección y conservación del Sur de Fuerteventura (Montes de Amanay y El Banquete)El proyecto INDEMARES ha permitido utilizar amplios medios económicos y personales para estudiar en detalle y desde múltiples perspectivas la zona del Sur de Fuerteventura (montes de Amanay y El Banquete). Se han aplicado metodologías para el estudio de la hidrografía, caracterizando la región, describiendo sus principales masas de agua y la hidrodinámica de las corrientes. También se ha abordado la geología de la zona, incluyendo levantamientos batimétricos, perfiles sísmicos, muestreos de sedimento y petrológicos, obteniendo modelos digitales del terreno, mapas de tipos de fondo, geomorfológicos. Se han caracterizado las comunidades bentopelágicas, demersales, epibentónicas y endobentónicas, prestando especial atención a aquellas que conforman o estructuran los hábitats sensibles cuyo inventariado y cartografía era objeto principal del proyecto. Los trabajos de identificación de hábitats se han realizado con muestreadores directos, pero también con muestreadores visuales, que han permitido hacer un mayor esfuerzo de muestreo sin aumentar el impacto sobre los fondos de la zona. Por otro lado se ha estudiado la huella pesquera de la zona por medio del análisis de los datos VMS y los cuadernos de pesca proporcionados por la SGP, además de una ardua labor a pie de puerto de entrevistas y encuestas. Toda la información ha sido gestionada y analizada por diferentes grupos de investigación de diferentes centros (Universidad de La Laguna, Instituto Universitario de Ciencias Políticas y Sociales, Universidad de Las Palmas de Gran Canaria, Instituto de Ciencias del Mar de Barcelona, Universidad de Barcelona, Centro de Investigaciones Medioambientales del Atlántico, Centro Oceanográfico de Santander y Centro Oceanográfico de Málaga del Instituto Español de Oceanografía, …), aunque el grueso de esta labor, además de la coordinación, se ha llevado a cabo en el Centro Oceanográfico de Canarias del Instituto Español de Oceanografía. Los resultados permiten tener un conocimiento profundo y multidisciplinar de la zona de estudio comparable a pocos proyectos de investigación marina en la Macaronesia. El estudio oceanográfico, el geológico, y el de las comunidades biológicas, ha permitido la caracterización de los hábitats de la zona, y su cartografiado mediante el intenso muestreo y la aplicación de análisis de idoneidad de hábitats.Abstract: INDEMARES Project made possible to bring together economic and staff resources to study in detail, and from multiple perspectives, the area of South of Fuerteventura (Amanay and El Banquete Semounts). Methodologies have been applied to study hydrography, making a regional characterization, depicting main water masses, and current hydrodynamics. Geology has been tackled including bathymetric uplifting, seismic profiles, sediment and petrological sampling, obtaining digital terrain models, type of bottom maps, geomorphological maps, as an output. Benthopelagic, demersal, epibenthic and endobenthic communities have been characterized, paying special attention to sensitive habitats which inventory and mapping was the project’s main aim. Habitat identification has been made with direct and visual samplers, the latter making a major sampling effort possible without an increase of bottom impact. Moreover, fisheries footprint has been identified by Vessel Monitoring System data, together with logbooks from Secretaría General de Pesca (Fisheries Ministry), as well as a hard interviewing and surveying task at landing points. Information has been managed and analysed by different research groups from different Centres (Universidad de La Laguna, Instituto Universitario de Ciencias Políticas y Sociales, Universidad de Las Palmas de Gran Canaria, Instituto de Ciencias del Mar de Barcelona, Universidad de Barcelona, Centro de Investigaciones Medioambientales del Atlántico, Centro Oceanográfico de Santander y Centro Oceanográfico de Málaga del Instituto Español de Oceanografía), although the main body of the work, plus coordination, has been made by the Canary Islands Oceanographic Centre, from the Spanish Institute of Oceanography. Results let us have a multidisciplinary profound knowledge of the study zone, comparable to few other marine research projects off Macaronesia. The study about oceanography, geology and biologic communities has allowed the habitats characterization and mapping by means of intensive sampling and habitat suitability analysis.Instituto Español de Oceanografía, Comisión Europea Programa LIFE+, Fundación Biodiversida

Caracterización del Banco de La Concepción

Se integra información hidrográfica, geomorfológica, sedimentológica, biológica, sobre hábitats marinos y pesquera, para establecer las bases ecológicas necesarias para la protección y conservación del Banco de La ConcepciónEl proyecto INDEMARES ha permitido utilizar amplios medios económicos y personales para estudiar en detalle y desde múltiples perspectivas la zona del Banco de La Concepción. Se han aplicado metodologías para el estudio de la hidrografía, caracterizando la región, describiendo sus principales masas de agua y la hidrodinámica de las corrientes. También se ha abordado la geología de la zona, incluyendo levantamientos batimétricos, perfiles sísmicos, muestreos de sedimento y petrológicos, obteniendo modelos digitales del terreno, mapas de tipos de fondo, geomorfológicos. Se han caracterizado las comunidades bentopelágicas, demersales, epibentónicas y endobentónicas, prestando especial atención a aquellas que conforman o estructuran los hábitats sensibles cuyo inventariado y cartografía era objeto principal del proyecto. Los trabajos de identificación de hábitats se han realizado con muestreadores directos, pero también con muestreadores visuales, que han permitido hacer un mayor esfuerzo de muestreo sin aumentar el impacto sobre los fondos de la zona. Por otro lado se ha estudiado la huella pesquera de la zona por medio del análisis de los datos VMS y los cuadernos de pesca proporcionados por la SGP, además de una ardua labor a pie de puerto de entrevistas y encuestas. Toda la información ha sido gestionada y analizada por diferentes grupos de investigación de diferentes centros (Universidad de La Laguna, Instituto Universitario de Ciencias Políticas y Sociales, Universidad de Las Palmas de Gran Canaria, Instituto de Ciencias del Mar de Barcelona, Universidad de Barcelona, Centro de Investigaciones Medioambientales del Atlántico, Centro Oceanográfico de Santander y Centro Oceanográfico de Málaga del Instituto Español de Oceanografía, …), aunque el grueso de esta labor, además de la coordinación, se ha llevado a cabo en el Centro Oceanográfico de Canarias del Instituto Español de Oceanografía. Los resultados permiten tener un conocimiento profundo y multidisciplinar de la zona de estudio comparable a pocos proyectos de investigación marina en la macaronesia. El estudio oceanográfico, el geológico, y el de las comunidades biológicas, ha permitido la caracterización de los hábitats de la zona, y su cartografiado mediante el intenso muestreo y la aplicación de análisis de idoneidad de hábitats.INDEMARES Project made possible to bring together economic and staff resources to study in detail, and from multiple perspectives, the area of Banco de La Concepción. Methodologies have been applied to study hydrography, making a regional characterization, depicting main water masses, and current hydrodynamics. Geology has been tackled including bathymetric uplifting, seismic profiles, sediment and petrological sampling, obtaining digital terrain models, type of bottom maps, geomorphological maps, as an output. Benthopelagic, demersal, epibenthic and endobenthic communities have been characterized, paying special attention to sensitive habitats which inventory and mapping was the project’s main aim. Habitat identification has been made with direct and visual samplers, the latter making a major sampling effort possible without an increase of bottom impact. Moreover, fisheries footprint has been identified by Vessel Monitoring System data, together with logbooks from Secretaría General de Pesca (Fisheries Ministry), as well as a hard interviewing and surveying task at landing points. Information has been managed and analysed by different research groups from different Centres (Universidad de La Laguna, Instituto Universitario de Ciencias Políticas y Sociales, Universidad de Las Palmas de Gran Canaria, Instituto de Ciencias del Mar de Barcelona, Universidad de Barcelona, Centro de Investigaciones Medioambientales del Atlántico, Centro Oceanográfico de Santander y Centro Oceanográfico de Málaga del Instituto Español de Oceanografía), although the main body of the work, plus coordination, has been made by the Canary Islands Oceanographic Centre, from the Spanish Institute of Oceanography. Results let us have a multidisciplinary profound knowledge of the study zone, comparable to few other marine research projects off Macaronesia. The study about oceanography, geology and biologic communities has allowed the habitats characterization and mapping by means of intensive sampling and habitat suitability analysis.Instituto Español de Oceanografía, Comisión Europea Programa LIFE+, Fundación Biodiversida

STANDARDIZED BIGEYE TUNA CPUE INDEX OF THE BAITBOAT FISHERY IN DAKAR (2005-2017)

The tuna baitboat fishery in Dakar (Senegal) has been operating permanently in the area off Senegal since the beginning of the 1950s. Details of the activity of this fleet can be found in Fonteneau & Diouf (1994), Hallier & Delgado de la Molina (2000) and, more recently, in several ICCAT documents (e.g., Pascual-Alayón et al., 2017, 2018). The number of vessels peaked at the end of the 1950s with 85-90 baitboats. Vessel productivity increased in the 1980s when a new technique was developed, the associated-school fishing method, whereas the baitboat maintains a permanent association with the tunas it fish. This method was described for the first time by Fonteneau & Diouf (1994). The Dakar-based fleet currently consists of 14 vessels: six Senegalese-flagged, seven Spanish-flagged, and one French-flagged. Annual catches of skipjack, yellowfin and bigeye are around 15,000 mt. In this document we have analysed the data corresponding to the seven Spanish flagged baitboat vessels. The activity of this fleet has traditionally taken place in the coastal areas between 14ºN and 21ºN (Figure 1). Their catch is composed mainly by skipjack and, to a lesser extent, by yellowfin and bigeye. In the last 5 years they represented 84%, 10% and 6% of the total catches, respectively. Over the period analysed in this document (2005-2017) the proportion of bigeye has oscillated without tendency between a maximum of 16% in 2006 and a minimum of 3% in 2013; the proportion of bigeye in the last year of this analysis, 2017, was 10%. The annual average catch of bigeye during this period has been 741.8 MT with a standard deviation of 313.8 MT (Figure 2). The average weight of the three tropical tuna species in the catches of this fleet is around 2-3 kg, 4-10 kg and 6-12 for skipjack, yellowfin and bigeye respectively. They have oscillated around these values without tendency during the last 25 years (Figure 17 of Delgado de Molina, A., et al. 2014). The Tropical Tuna Workplan adopted by the SCRS in 2017 included the update of standardized bigeye CPUE indices until 2017 for the European baitboat fleet operating in Dakar. In this working document we present the analyses carried out with detailed VMS and logbook data from this fleet for the most recent period for which both sources of information were available