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-Unsuitable management of fisheries may lead to overexploitation of marine resources. Oceanic islands with narrow continental shelves, in particular, are sensitive to unsustainable levels of fishing intensity. Fish traps are the modality of artisanal professional fishing more important in the coastal waters of the Canary Islands (eastern Atlantic) to capture demersal resources, which are deployed all year-round and allow a release of undersized captures. We aimed at studying the structure of nearshore fish assemblages through deployment of benthic bottom traps carried out at Gran Canary Island. A quantitative description of catches, in terms of abundance, biomass and sizes, of traps deployed from May to October 2009, between ca. 20 to 50 m depth, was carried out. We used this information to test whether the structure of nearshore fish assemblages at the island scale varied between three zones located at the NW, NE and E of the island with varying habitat structure. A total of 58 species (22 families) were collected for the overall study from a total of 2568 deployed traps. The species Sparisoma cretense (25% of the total biomass), the family Sparidae (16 species, 44%) and Mullus surmuletus (4%) accounted for more than 73% of the total catch in terms of biomass. The parrotfish, S. cretense, was the fish with the largest catches in terms of number of individuals, followed by Dentex gibbosus, Diplodus vulgaris, Stephanolepis hispidus, Chromis limbata and Mullus surmuletus. Differences in the structure of the fish assemblage at the island scale were not predicted by differences in the type of bottom. Fishing yields were similar between the NW (0.16 ± 0.02 kg trap −1 day −1 ) and NE side of the island (0.19 ± 0.01 kg trap −1 day −1 ), being lower at the E zone (0.15 ± 0.01 kg trap −1 day −1 ). The most abundant species, the parrotfish S. cretense, had a mean size close to its first maturity sizes (SFM 50 ), while both D. gibbosus and D. vulgaris were below SFM 50 . In general, the mean size of Sparids was well below SFM 50 , an indication of overexploitation, while M. surmuletus and S. hispidus reached a mean size beyond their first maturity sizes.

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During the past 20 years, experimental cruises have been conducted around the Canary Islands (North-West Africa) to investigate the biodiversity of the deep-sea ecosystem and to explore new fisheries resources. Although pandalid shrimps were shown to be very abundant in this region, information is lacking regarding the best fishing method for catching the different species of shrimp. Here, two types of traps were tested, a semi-floating shrimp trap and a traditional bottom trap, in an effort to improve the fishing gear effectiveness and to reduce the capture of non-target species. In total, nine species were captured, which were categorised into three main groups based on their depth of capture: Plesionika edwardsii, P. narval and P. holtuisi (100-400 m); P. ensis, P. martia, P. williamsi and Heterocarpus ensifer (400-800 m); and H. grimaldii and H. laevigatus (800-1 300 m). Significant differences were found in the capture of the different species: P. narval, P. ensis, P. edwardsii and H. ensifer were captured more readily using the semi-floating traps, whereas P. martia, P. williamsi, H. grimaldii and H. laevigatus were caught more efficiently with traditional bottom traps. This intra-specific difference in their capture was considered to be due to the differential motility of the species in the water column. There were indications that P. edwardsii and H. ensifer are an unexploited resource that has the potential to support a viable and sustainable fishery using semi-floating shrimp traps. Furthermore, the deeper-dwelling pandalid shrimps, H. laevigatus and H. grimaldi, could be a secondary target species using bottom traps.

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Summary:Similiparma lurida is a common fish inhabiting shallow-water rocky bottoms of the northeastern Atlantic oceanic archipelagos, and the coasts from Portugal to Senegal. This study was conceptualized to integrate information relative to key population traits of S. lurida, including length and age structure, growth, reproduction and length at maturity, with a description of abundance patterns on shallow reefs, including temporality of recruitment and habitat preferences by juveniles, sub-adults and adults. We then hypothesized that seasonal cycles of spawning and recruitment were synchronized. This species reaches a total length (TL) of up to 15.7 cm and an age of 18 years. Males grow faster and longer (K=0.28 years -1 , L ∞ =14.487 cm TL) than females (K=0.23 years -1 , L ∞ =13.461 cm TL), which affects the overall ratio of males to females (1:0.26). The size at which 50% of sexual maturity is reached was 10.344 cm TL for males and 8.471 cm TL for females. Fish increase growth during the spawning season, which occurs from November to March, including a maximum in February. After two months of this peak, juveniles reached maximum abundances (April) in high relief reef areas. Adults, however, show a preference towards rocky bottoms covered with algae interspersed with sand patches, suggesting ontogenetic changes in microhabitat preferences when juveniles turn into adults.Keywords: Pomacentridae; Similiparma lurida; life history; recruitment; coastal fish; spatial distribution; northeastern Atlantic.Estrategias de vida de un relevante pez de arrecife, la fula negra Similiparma lurida (Pomacentridae) en el Noroeste Atlántico Resumen: Similiparma lurida es un pez común que habita en aguas poco profundas de fondos rocosos someros de los archipiélagos oceánicos del Atlántico Norte, y las costas desde Portugal a Senegal. Este estudio se conceptualizó para integrar información relativa a atributos poblacionales clave de S. lurida, incluyendo: estructura de tallas y edad, crecimiento, reproducción y talla de primera madurez con la descripción de los patrones de abundancia en arrecifes poco profundos, incluyendo la temporalidad en el reclutamiento y preferencias de hábitat por juveniles, sub-adultos y adultos. Esta especie alcanza hasta 15.7 cm de longitud total (LT) y 18 años de edad. Los machos crecen más rápido y son más largos (K=0.28 years -1 , L ∞ =14.487 cm LT) que las hembras (K=0.23 years -1 , L ∞ =13.461 cm LT), lo que afecta a la sex ratio de machos y hembras (1:0.26). El tamaño en el que se alcanza el 50% de la madurez sexual fue 10.344 cm (LT) para los machos y 8.471 cm (LT) para las hembras. El crecimiento es mayor durante la temporada de desove, que ocurre de noviembre a marzo, incluyendo un máximo reproductivo en febrero. Dos meses después de este pico (abril), los juveniles alcanzaron abundancias máximas en zonas de arrecifes de gran relieve. Los adultos, sin embargo, muestran una preferencia hacia los fondos rocosos cubiertos de algas intercaladas con parches de arena, lo que sugiere cambios ontogené...

Ribeiro P.A., Gonçalves J.M., Chavan G., Fricke R., García-Mederos A.M., Tuset V.M., Barreiros J.P. 2017.First record of the cubera snapper, Lutjanus cyanopterus (Actinopterygii: Perciformes: Lutjanidae), from the Azores (NE Atlantic) and possible range extension for the east Atlantic. Acta Ichthyol. Piscat. 47 (3): 259-263. Background.A lutjanid recently captured in Flores Island represents the first documented record of a snapper for the Azores Islands. Since this specimen was not made available to us besides photographs and a muscle sample, a genetic study approach was necessary in order to accurately describe and discuss this somewhat unexpected occurrence. The main objective of this paper was to explain and discuss the presence of this single specimen in this part of the north-eastern Atlantic. Materials and methods. The specimen was caught by spear fishers on 30 July 2014 off Flores Island. We analysed all available photographs and a sample of muscle tissue that was taken and preserved frozen to be used for DNA barcoding.Results. The specimen was a reproductively mature female with a total length of 108.7 cm and weighing 14.84 kg. The body depth of the specimen from the Azores was 2.9 in SL and the analyses conducted showed no divergence from the Canary Islands specimen reported by García-Mederos and Tuset (2014) as Lutjanus dentatus (Duméril, 1861) with the body depth of 2.5 in SL, which demonstrates that this character is highly variable and not useful for species identification. Conclusions. The snapper specimen from the Island of Flores is a Lutjanus cyanopterus (Cuvier, 1828) and confirmed as first record for this part of the north-eastern Atlantic. Comparisons with a L. dentatus from the Canary Islands point towards synonymy although the available molecular evidence is too scarce and by no means conclusive.

The present study provides fisheries biology knowledge which will allow the implementation of regulatory measures contributing to the sustainability of the fisheries and the conservation of the stout beardfish Polymixia nobilis Lowe, 1838 off the Canary Islands, north eastern Atlantic Ocean. Males ranged between 16.5 and 38.4 cm fork length (FL) and females from 14.2 to 46.5 cm FL. Sex ratio by size classes provided significant differences in classes higher than 36 cm, being clearly unbalanced in favour of females. Individuals in maturing and mature stages were present during all months sampled, although a spawning peak is evident between April and June. Size at first maturity was estimated as 26 cm FL for females and 30 cm FL for males. Age was determined from annuli in whole otoliths. Age range was found to be 0-14 years for fish measuring 14.2 to 46.5 cm FL. It is a slow-growing and long-lived species. Significant differences in the growth parameters between sexes were detected. The von Bertalanffy growth parameters estimated for females (n = 213) were L ¥ = 45.92 cm LF, k = 0.16 years )1 and t 0 = )2.84 years; and for males (n = 186) L ¥ = 36.44 cm LF, k = 0.26 years )1 and t 0 = )2.16 years. Stomach analysis indicated some variations in the feeding habits with growth: individuals of small and medium sizes preyed on crustaceans and fishes, while large specimens preyed mainly on fishes.