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Sponges (phylum Porifera) are benthic filter-feeding animals that play an important role in nutrient cycling and habitat provision in the deep sea. Sponges collected between 2010 and 2014 during annual multispecies trawl surveys conducted by Fisheries and Oceans Canada (DFO) in Baffin Bay, Davis Strait and portions of Hudson Strait were taxonomically examined. In total ~2500 specimens were identified, comprising over 100 sponge taxa. Sponges from the order Poecilosclerida comprised nearly half the identified species. This report summarizes sponges from the family Dendoricellidae (class Demospongiae, subclass Heteroscleromorpha, order Poecilosclerida) and family Tedaniidae (class Demospongiae, subclass Heteroscleromorpha, order Poecilosclerida). A total of six species are described, from genera Dendoricella (Dendoricellidae) and Tedania (Tedaniidae). These species are: Dendoricella flabelliformis, Dendoricella cf. flabelliformis, Dendoricella aff. flabelliformis, Dendoricella sp. 1, Tedania (Tedania) suctoria, and Tedania sp. 1. Descriptions include morphological and spicule descriptions, spicule dimensions, and taxonomic discussion. Les éponges (phylum Porifera) sont des animaux filtreurs benthiques qui jouent un rôle important dans le cycle des éléments nutritifs et la production d'habitats dans les profondeurs de la mer. Les éponges recueillies au cours des relevés plurispécifiques annuels au chalut entre 2010 et 2014 effectués par Pêches et Océans Canada (MPO) dans la baie de Baffin, le détroit de Davis et certaines parties du détroit d'Hudson ont été examinées sur le plan taxonomique. Au total, 2 500 spécimens ont été identifiés, et ceux-ci représentaient plus de 100 taxons d'éponges. Presque la moitié des espèces recensées étaient de l'ordre Poecilosclerida. Le présent rapport fait état des éponges appartenant à la famille Dendoricellidae (classe Demospongiae, sous-classe Heteroscleromorpha, ordre Poecilosclerida) et à la famille Tedaniidae (classe Demospongiae, sous-classe Heteroscleromorpha, ordre ...

ABSTRACT. Sponges (phylum Porifera) are benthic filter feeding animals that play an important role in nutrient cycling and habitat provision in the deep sea. Sponges collected between 2010 and 2014 during annual multispecies trawl surveys conducted by Fisheries and Oceans Canada in Baffin Bay, Davis Strait and portions of Hudson Strait were taxonomically examined. In total ~2500 specimens were identified, comprising ~100 known sponge taxa. Sponges from the order Poecilosclerida comprised nearly half of the identified species. Sponges from the poescilosclerid families Coelosphaeridae, Crellidae, Dendoricellidae, Myxillidae and Tedaniidae are described in previous reports. This report adds descriptions of eight sponge species from three poescilosclerid families: Microcionidae, Acarnidae and Esperiopsidae (class Demospongiae, subclass Heteroscleromorpha, order Poecilosclerida). Described species include Artemisina lundbecki, Artemisina arcigera, and Clathria (Clathria) barleei from the family Microcionidae, Iophon piceum and Iophon koltuni from the family Acarnidae, and Esperiopsis villosa, Esperiopsis sp. 1, and Semisuberites cf. cribrosa from the family Esperiopsidae. Descriptions include physical description of the sponges, descriptions and dimensions of their spicules, and taxonomic discussion. RÉSUMÉ. Les éponges (phylum Porifera) sont des animaux filtreurs benthiques qui jouent un rôle important dans le cycle des éléments nutritifs et qui augmentent la disponibilité d'habitats benthiques en eaux profondes. Les éponges collectées au cours des relevés plurispécifiques annuels au chalut effectués entre 2010 et 2014 par Pêches et Océans Canada dans la baie de Baffin, le détroit de Davis et certaines portions du détroit d'Hudson ont été examinées sur le plan taxonomique. Au total, environ 2500 spécimens ont été identifiés, appartenant à ~100 taxons d'éponges connus. Presque la moitié des espèces recensées appartiennent à l'ordre Poecilosclerida. Parmi elles, les éponges des familles Coelosphaeridae, Crellidae, ...

Data from MEDITS trawl surveys in the waters surrounding the Maltese Islands were analysed to characterise the benthic and demersal assemblages of the central Mediterranean, which are only poorly known, hampering Maltese authorities in meeting legislative obligations. A total of 147 benthic species and 98 demersal species were identified. These formed four well-defined assemblages, whose structure and composition were related to depth. Total species richness and abundance of both demersal and benthic species decreased with depth. The most abundant structuring epibenthic species which characterised the identified assemblages were the tall sea pen Funicularia quadrangularis (present at depths of ca. 50–700 m), the red sea pen Pennatula rubra (ca. 100–450 m), the hydroids Lytocarpia myriophyllum (ca. 100–250 m) and Nemertesia sp. (ca. 100–600), the soft coral Alcyonium palmatum (ca. 100–400 m), and the anemone Actinauge richardi (ca. 100–600 m). These results illustrate how, in the absence of dedicated benthic mapping studies, MEDITS data can be used to provide preliminary information that would not otherwise be available. ; peer-reviewed

41e Congres de la Commission Internationale pour l'Exploration Scientifique de la Mer Méditerranée (CIESM), 12-16 September 2016, Kiel.-- 1 page, 2 tables ; The issue of the fishery discards is of great interest in fishery management from the new policy of the European Union 2013 ((EU) No 1380/2013) which proposes a gradual reduction of discards. In the framework of the European project >Science, Technology, and Society Initiative to minimize Unwanted Catches in European Fisheri es> MINOUW (H2020-SFS-2014-2) a seasonal study between the years 2011-2012 was conducted in order to assess the discard composition and the invertebrate survival coming from the trawl metier for hake in the Catalan Coast (Palamós Port). Some of the main species discarded were Alcyonium palmatum and undersize Merluccius merluccius. Sessile invertebrates as Alcyonium palmatum showed high rates of survival, while species of echinoderms as Astropenten irregularis or crustaceans as Pagurus excavatus displayed lower rates ; Peer Reviewed

Not Available ; The areawise and depth wise cephalopod catches of fishing vessels of Government of India and some Agencies which conducted exploratory fishing in offshore areas have been presented and discussed. The exploratory fishing by Government of India vessels in Bombay-Gujarat region during 1977-80 yielded a maximum of 7,609 kg of cephalopods a year at a catch rate of 6.8 kg/h. The highest catch rates were recorded from the area 19-70 and the depth zone 80-89 m. In Visakhapatnam region the cephalopod catch was poor during 1968-75 but during 1977-80 the annual catch increased to 3,283 kg. The most intensively fished area was 17-83. The catch was composed of four species of cuttlefishes and three species of squids. The results of trawl surveys in other parts of Indian waters are also dealt with. ; Not Available

AbstractThis study provides new insights onto spatial and temporal trends of seafloor macro-litter in the abyssal seafloor of Sardinian channel, in central western Mediterranean (Italy). Trawl surveys were conducted at depths between 884 and 1528 m, thus focusing on one of the least investigated marine environments. None of the considered sites was litter free, with plastics being numerically dominant (57% of items), followed by metal (11%) and glass (16%). Recorded densities and weight ranged between 49.9 and 499 items km−2 and 1.4 and 1052 kg km−2. In the most contaminated sites, the weight of the litter collected in nets represented up to nine times the biomass of benthic megafauna, and, overall, in 60% of hauls macro-litter mass outweighed the biomass collected. Moreover, we report that megafauna was observed to be more abundant in sites where macro-litter presence was more severe. More studies are needed to elucidate the nature of this correlation, with biota being more abundant in hotspots of accumulation of seafloor macro-litter.

Trawl fisheries have been operating in South African waters for roughly 110 years. In contrast to other trawl fisheries, the South African fishery was opened by government-funded scientific trawl surveys beginning in 1898. Detailed records of survey trawls undertaken immediately prior to and during the beginning of commercial trawling activity provided a rare opportunity to examine longterm changes in fish abundance. This dissertation focuses on the chondrichthyans, which are believed to be the group of fishes most at risk from intense exploitation. Despite some problems associated with changes in taxonomy and the efficiency of gear, this analysis was able to compare two distinct periods at three taxonomic levels: The periods were taken to represent baseline values prior to the opening of trawl fisheries and contemporary data, separated by roughly 80 years of intense, trawling activity. Three historically important trawl grounds were identified as having sufficient samples from each period. Between the surveys, trawl velocity did not deviate much from contemporary trawl velocities, although all surveys were found to have a significantly different velocity. In respect to the catch composition, significant changes were found in the relative abundance of the total catch composition, as a general shift from large, long-lived species towards smaller species was found. This applied both for teleosts as well as chondrichthyans, with the entire chondrichthyan catch composition showing a decrease, with the exception of Callorhinchus capensis, which increased significantly. Changes in chondrichthyan swept-area density were found to follow those trends found in the relative abundance: An increase was found in Callorhinchus capensis, whereas all other species decreased. All chondrichthyans were classed in low productivity categories and were assigned a high risk factor to overfishing. Reasons for the declines in the chondrichthyan assemblage were low fecundity, slow maturation and the inability due to these factors to adapt to an environment altered by trawling. Only in the case of Callorhinchus capensis were secondary effects of trawling such as the removal of competitor species likely to have caused the increase in relative abundance and swept area density as well as Callorhinchus capensis having a relatively high fecundity among chondrichthyans. In general, chondrichthyan decreases exceeded those of teleosts, and this work provides broad empirical support for the hypothesis that the low fecundity and slow growth of chondrichthyan species places this group at higher risk than teleosts.

37 páginas, 7 figuras, 29 tablas.-- Scientific Council Meeting ; A stratified random bottom trawl survey of Flemish Cap was carried out in July 1998 up to a depth of 730 metres. Survey results are presented and compared with results of previous surveys in the series since 1988. Abundance at age indices are presented for cod, American plaice, redfish (Sebastes mentella and S. fasciatus) and Greenland halibut ; This study was supported by the European Commission (DG XIV, Study 96-030), CSIC, IEO, IPIMAR and the Basque Government ; Peer reviewed

43 páginas, 8 figuras, 28 tablas.-- Scientific Council Meeting ; A stratified random bottom trawl survey on Flemish Cap was carried out on July 2001 up to a depth of 730 metres. Survey results are presented and compared with results of previous surveys in the series since 1988. Abundance-at-age indices were presented for cod, American plaice, redfish and Greenland halibut ; This study was supported by th e European Commission (DG XIV, Study 00 - 028), CSIC, IEO, IPIMAR and the Basque Government ; Peer reviewed

56 páginas, 33 tablas, 9 figuras.-- Scientific Council Meeting ; A stratified random bottom trawl survey on Flemish Cap was carried out on July 2000 up to a depth of 730 metres. Survey results are presented and compared with results of previous surveys in the series since 1988. Abundance at age indices are presented for cod, American plaice, redfish and Greenland halibut. Results from a comparative trial between the survey gear (Lofoten) and a Campelen 1800 shrimp trawl are presented ; This study was supported by the European Commission (DG XIV, Study 98-048), CSIC, IEO, IPIMAR and the Basque Government

Aim: Trawling leads to widespread direct human disturbance on the seabed. Knowledge of the extent and consequences of this disturbance is limited because large-scale distributions of seabed fauna are not well-known. We map faunal distributions in the Australian Exclusive Economic Zone (EEZ) and quantify the proportion of their abundance that occurs in areas 1) that are directly trawled, and 2) where legislation permanently prohibits trawling — defined as percentage exposure or protection respectively. Our approach includes developing a method that integrates data from disparate seabed surveys to spatially expand predicted benthos distributions. Location: Australia Methods: We collate data from 18 seabed surveys to map the distribution of seabed invertebrates (benthos) in nine regions. Our approach combines data from multiple surveys, groups taxa within taxonomic classes, and uses Random Forests to predict spatial abundance distributions of benthos groups from environmental variables. Exposure and protection of benthos groups were quantified by mapping their predicted abundance distributions against the footprint of trawling and legislated boundaries of marine reserves and fishery closures. Results: Trawling is currently prohibited from more area of Australia's EEZ (58%) than is trawled (<5%). Across 134 benthos-groups, 96% had greater protection of abundance than exposure. The mean trawl exposure of benthos-group abundance was 7%, compared to mean protection of 38%; whereas the mean abundance neither trawled nor protected was 55%. Fishery closures covered 19% less study area than marine reserves, but overlapped with a higher proportion (5% more) of benthos-group abundance. Main Conclusions: This study provides the most extensive quantitative assessment of the current exposure of Australia's benthos to trawling. Further, it highlights the contribution of fishery closures to marine conservation. These results help identify regions and taxa that are at greatest potential risk from trawling, and supports managers to achieve balance between conservation and sustainable industries in marine ecosystems.

A four-year time series (1994-1997) of groundfish trawl surveys performed within the European Union Project MEDITS (Mediterranean International Trawl Surveys), was analysed to identify and describe the fish assemblages along the continental shelf and slope of Tuscany and Latium (Italy), in the north-western Mediterranean. Cluster analysis was used to group samples with similar species composition in terms of abundance, biomass and frequency of occurrence. Results allowed the identification of four to five broad assemblages along the depth gradient: a strictly coastal group (< 50 m depth), two groups in the upper and lower part of the continental shelf (essentially 50-200 m), an epibathyal group (200-450 m) and a group derived from hauls made at depths greater than 450 m. Each assemblage corresponded to a faunistic association with relatively homogeneous and persistent species composition, biomass and density indices. ; No disponible

Aim: Trawling is the most widespread direct human disturbance on the seabed. Knowledge of the extent and consequences of this disturbance is limited because large-scale distributions of seabed fauna are not well known. We map faunal distributions in the Australian Exclusive Economic Zone (EEZ) and quantify the proportion of their abundance that occurs in areas 1) that are directly trawled and 2) where legislation permanently prohibits trawling—defined as percentage exposure or protection, respectively. Our approach includes developing a method that integrates data from disparate seabed surveys to spatially expand predicted benthos distributions. Location: Australia. Methods : We collate data from 18 seabed surveys to map the distribution of seabed invertebrates (benthos) in nine regions. Our approach combines data from multiple surveys, groups taxa within taxonomic classes and uses Random Forests to predict spatial abundance distributions of benthos groups from environmental variables. Exposure and protection of benthos groups were quantified by mapping their predicted abundance distributions against the footprint of trawling and legislated boundaries of marine reserves and fishery closures. Results: Trawling is currently prohibited from more area of Australia's EEZ (58%) than is trawled (<5%). Across 134 benthos groups, 96% had greater protection of abundance than exposure. The mean trawl exposure of benthos-group abundance was 7%, compared to mean protection of 38%, whereas the mean abundance neither trawled nor protected was 55%. Fishery closures covered 19% less study area than marine reserves, but overlapped with a higher proportion (5% more) of benthos-group abundance. Main Conclusions: This study provides the most extensive quantitative assessment of the current exposure of Australia's benthos to trawling. Further, it highlights the contribution of fishery closures to marine conservation. These results help identify regions and taxa that are at greatest potential risk from trawling and support managers to achieve balance between conservation and sustainable industries in marine ecosystems.

50 páginas, 8 figuras, 35 tablas.-- Scientific Council Meeting ; A stratified random bottom trawl survey on Flemish Cap was carried out on July 1999 up to a depth of 730 metres. Survey results are presented and compared with results of previous surveys in the series since 1988. Abundance at age indices are presented for cod, American plaice, redfish and Greenland halibut. Results from a comparative trial between the survey gear (Lofoten) and a Campelen 1800 shrimp trawl are presented. ; This study was supported by the European Commission (DG XIV, Study 98-048), CSIC, IEO, IPIMAR and the Basque Government. ; Peer reviewed