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Deep-sea anglerfishes are relatively abundant and diverse, but their luminescent bacterial symbionts remain enigmatic. The genomes of two symbiont species have qualities common to vertically transmitted, host-dependent bacteria. However, a number of traits suggest that these symbionts may be environmentally acquired. To determine how anglerfish symbionts are transmitted, we analyzed bacteria-host codivergence across six diverse anglerfish genera. Most of the anglerfish species surveyed shared a common species of symbiont. Only one other symbiont species was found, which had a specific relationship with one anglerfish species, Cryptopsaras couesii. Host and symbiont phylogenies lacked congruence, and there was no statistical support for codivergence broadly. We also recovered symbiont-specific gene sequences from water collected near hosts, suggesting environmental persistence of symbionts. Based on these results we conclude that diverse anglerfishes share symbionts that are acquired from the environment, and that these bacteria have undergone extreme genome reduction although they are not vertically transmitted., eLife digest The deep sea is home to many different species of anglerfish, a group of animals in which females often display a dangling lure on the top of their heads. This organ shelters bacteria that make light, a partnership (known as symbiosis) that benefits both parties. The bacteria get a safe environment in which to grow, while the animal may use the light to confuse predators as well as attract prey and mates. The genetic information of these bacteria has changed since they became associated with their host. Their genomes have become smaller and more specialized, limiting their ability to survive outside of the fish. This phenomenon is also observed in other symbiotic bacteria, but mostly in microorganisms that are directly transmitted from parent to offspring, never having to live on their own. Yet, some evidence suggests that the bacteria in the lure of anglerfish may be spending time in the water until they find a new host, crossing thousands of meters of ocean in the process. To explore this paradox, Baker et al. looked into the type of bacteria carried by different groups of anglerfish. If each type of fish has its own kind of bacteria, this would suggest that the microorganisms are passed from one generation to the next, and are evolving with their hosts. On the other hand, if the same sort of bacteria can be found in different anglerfish species, this would imply that the bacteria pass from host to host and evolve independently from the fish. Genetic data analysis showed that amongst six groups of anglerfishes, one species of bacteria is shared across five groups while another is specific to one type of fish. The analyses also revealed that anglerfish and their bacteria are most likely not evolving together. This means that the bacteria must make the difficult journey from host to host by persisting in the deep sea, which was confirmed by finding the genetic information of these bacteria in the water near the fish. Anglerfish and the bacteria that light up their lure are hard to study, as they live so deep in the ocean. In fact, many symbiotic relationships are equally difficult to investigate. Examining genetic information can help to give an insight into how hosts and bacteria interact across the tree of life.

12 pages, 9 figures, 2 tables, The presence of emergent visible parasites at commercial valuable fish species is increasingly causing problems at fisheries and seafood industries. Microsporidians have been previously reported to appear forming apparent xenomas complexes in anglerfish species, but no effort has been carried out to simultaneously integrate epidemiological data, phenotypic, genotypic and fine structural characterizations in the same parasite sample. In this work, specimens of Lophius budegassa and Lophius piscatorius from NE Atlantic waters were sampled and examined to provide information about specific site of infection and demographic data of two groups of different sizes of xenomas present at both fish species. Histological descriptions and scanning and transmission electron microscopy were carried out on fresh spores of Lophius budegassa for ultrastructural studies. In both types of xenomas, it was observed simultaneously the microsporidian genus Spraguea in the form of two different types of spores. Molecular analyses of both xenomas from the two fish species, based on the small subunit ribosomal DNA gene, were also performed to genetically support the morphological diagnostic provided., Xunta de Galicia has funded this work under Projects INCITE-07MMA015CT, IN841C, 10TAL 001CT and 10TAL033E. M. Llarena-Reino thanks Fundação para a Ciência e a Tecnologia for its financial support (Grant SFRH/BD/45398/2008).

The interdependence of diverse organisms through symbiosis reaches even the deepest parts of the oceans. As part of the DEEPEND project (deependconsortium.org) research on deep Gulf of Mexico biodiversity, we profiled the bacterial communities (‘microbiomes’) and luminous symbionts of 36 specimens of adult and larval deep-sea anglerfishes of the suborder Ceratioidei using 16S rDNA. Transmission electron microscopy was used to characterize the location of symbionts in adult light organs (esca). Whole larval microbiomes, and adult skin and gut microbiomes, were dominated by bacteria in the genera Moritella and Pseudoalteromonas. 16S rDNA sequencing results from adult fishes corroborate the previously published identity of ceratioid bioluminescent symbionts and support the findings that these symbionts do not consistently exhibit host specificity at the host family level. Bioluminescent symbiont amplicon sequence variants were absent from larval ceratioid samples, but were found at all depths in the seawater, with a highest abundance found at mesopelagic depths. As adults spend the majority of their lives in the meso- and bathypelagic zones, the trend in symbiont abundance is consistent with their life history. These findings support the hypothesis that bioluminescent symbionts are not present throughout host development, and that ceratioids acquire their bioluminescent symbionts from the environment., Molecular characterization of bioluminescent bacterial symbionts and comparison with bacteria at other body parts in six families of anglerfish of the Gulf of Mexico.

The early life history of the angler Lophius piscatorius in the Bay of Biscay was investigated by growth increments in the lapillar otoliths, this being the first time this type of analysis was conducted for this species among specimens of the Iberian stock (ICES Divisions 8.c, 9.a). Lapilli of 34 juvenile fish collected during autumn bottom trawl surveys, were successfully aged between 113 and 198 days (116–213 mm fish length). Morphology and ultrastructure analyses of the otolith’s check marks enabled us to determine the period of endogenous feeding (which according to these estimations would last between 9 and 19 days after hatching), as well as the settlement check, which indicated a relatively long pelagic phase (ca. 91 days). Hatch date was back-calculated from the date of capture indicating a spawning period from April to June, in agreement with that estimated for this population. The age–length relationship was described by the linear function LT = 7.30 + 0.98 age (days) and showed an average growth rate of 0.98 mm day−1 . Our results present a faster growth pattern of 0+ juveniles L. piscatorius in the Bay of Biscay than previously estimated by annual growth studies, showing that juveniles of up to 213 mm length collected in October were hatched in the same year and belonged to age class 0. These results are relevant to the knowledge of the early life history of this species and are in agreement with those obtained in the only previous microstructural study of L. piscatorius in Atlantic waters. The implications of these findings on the annual age estimation protocol based on illicia are discussed., Sí

Several studies in the last 20 years have revealed that morphological asymmetry in fish can be characterized as ‘antisymmetry’. Antisymmetry is a lateral dimorphism in which each population consists of individuals with well-developed left sides (lefties) and well-developed right sides (righties). This dimorphism influences predator–prey interactions. In some piscivorous fishes, it has been found that predators can catch more prey of the opposite morphological type to themselves (cross-predation) than of the same morphological type (parallel-predation). Our previous work clarified that the predominance of cross-predation is caused by lateralized behaviors of predators and prey that correspond to their morphological antisymmetry. Moreover, based on the results of our behavioral observations, we hypothesized that parallel-predation can predominate when predators encounter the potential prey frontally. To test this hypothesis, in the present study we investigated the relationship between lateral morphological types of anglerfish (Lophiomus setigerus) and those of the prey fishes found in their stomachs. Anglerfish attract potential prey using their first dorsal fin (illicium) as a lure, and their frontal encounters with potential prey fishes were photographed in situ and observed in an aquarium. The results of a stomach contents analysis indicated that parallel-predation predominated in five benthopelagic prey fish species (perches and eels). By contrast, five benthic prey fishes (gobies and weevers) exhibited the predominance of cross-predation. These results not only demonstrate the predominance of parallel-predation in a natural fish community, but also suggest that the relationship between morphological types of predator and prey species can be reversed depending on the lifestyle of prey.

Summary A survey-based assessment of an eastern Mediterranean data-limited black anglerfish (Lophius budegassa; Spinola, 1807) stock was carried out to elucidate its population and exploitation trends. A catch-based method was also applied to estimate its maximum sustainable yield (MSY). The effect on the long-term spawning stock biomass and yield of a wide range of exploitation regimes (combinations of F and selectivity) was investigated using an age-structured population model parameterised for Mediterranean anglerfish stocks. The analysis indicated an increasing trend of anglerfish fishing mortality (F) in the eastern Mediterranean from the mid-1990s onwards, and that recent catches were 41% higher than the median MSY estimate. Catching Mediterranean anglerfish at least three years after they mature at an F = 0.4–1 year−1 would ensure high yields at sustainable levels of stock depletion. Examination of the empirical exploitation regimes in five anglerfish stocks across the Mediterranean Sea illustrates their unfulfilled potential for higher sustainable yields, mainly due to overexploitation of juveniles.

Spotted handfish are a critically endangered anglerfish. Monitoring of the species has, in the past, been undertaken via underwater visual census (UVC) parameterised with fixed length 100 m × 3 m strip transects measured with reel lines. However, the sparse distribution and cryptic nature of handfish resulted in low statistical power to track populations through time. To achieve reasonable confidence of detecting change ~ 40 transects are required for density estimates, making the logistical constraints of monitoring onerous. We trialled a new survey method for UVC at one study site with a known local population of fish, replacing reel transects with variable length strip transects parameterised with a diver towed Global Positioning System (GPS) float. From 18 transects we determined a density of 24 (± 3.5) handfish per hectare, but bootstrapping suggested little improvement in precision occurred after 8 transects. Modelling these results to previous estimates at the site indicated that our GPS float approach required many fewer transects and dives to determine 50% increases or decreases in fish densities. This improvement was partly due to the better sampling efficiency; with 3 times the average search area per transect but was also a result of longer transects being a better solution for monitoring a sparse population. Our results returned a normal sample distribution of fish counts with few zeros and many multiple observations, which differed to the original approach which was heavily skewed towards zero observations per transect. However, at very low population densities even this more robust solution will require many samples to detect change. Our GPS parameterized surveys also improved the functionality of observing fish behaviour as we could accurately plot fish allowing for detailed investigation of distributions. When fish were observed they were also bi-laterally digitally photographed to record their unique natural markings. By synchronising the photographs timestamp with the GPS clock, we were able to geo-locate individual recaptures and our preliminary results suggests net movements were limited. This new approach increases the logistical feasibility for monitoring spotted handfish and may have applications for other sparsely distributed benthic species.

A new species of the deep-sea ceratioid anglerfish genus Oneirodes Lutken (Lophiiformes: Oneirodidae) is described on the basis of a single female specimen collected from the Western Indian Ocean. The new form is distinguished from its congeners by a combination of features that includes a relatively short illicium, a unique escal morphology, and shape of the subopercle bone.

The present article is the first to describe the diet of the black anglerfish Lophius budegassa, an opportunistic, non-selective, ambush predator, on the upper slope of the south eastern Mediterranean Sea. The deep-water rose prawn, Parapenaeus longirostris, and the short nose green eye, Chlorophthalmus agassizi, are identified as its main prey items. We used stomach contents as a proxy of prey availability, thus reflecting the local species abundance in the warm, oligotrophic environment of the south eastern Levant. Current models predict increasing temperatures and oligotrophy in the Mediterranean Sea. The results of this study depicting the diet of the Levantine population of L. budegassa, which varies from other Mediterranean populations, could indicate possible Mediterranean-wide shifts in prey distribution and abundance driven by climate change and anthropogenic disturbance. In addition, we augment the knowledge regarding the species’ feeding ecology, especially regarding possible sex and size dissimilarity. We propose the use of diet analyses from non-selective predators like L. budegassa as a mean to identify changes in community compositions and differences among communities.

Due to global declines, skates and sharks have become a focus of marine conservation in recent years. Despite protective measures, they remain vulnerable to bycatch by fisheries, especially bottom-trawls and pose a problem for fisheries management measures that aim to eliminate discards in the future. In the mixed-species bottom-trawl fisheries of the North Atlantic catches can be increased by fitting a length of chain known as a “tickler” in front of the groundgear of the trawl. It was hypothesized that the tickler is especially effective at catching skates and rays that may otherwise escape beneath the net. A trial was undertaken with paired tows with and without the tickler chain. The trial demonstrated that the catch rate of skates and sharks can be significantly lowered by removing the tickler. A set of secondary nets (groundgear bags) attached behind the groundgear of the main net allowed the number of fish escaping under the net to be estimated and showed that the reduction of skates and sharks in the main net was accompanied by an increase in number in the groundgear bags. This suggests that prohibition of the use of tickler chains in areas that are known to be especially important to skates and sharks could have conservation benefits. The removal of the tickler chain had little effect on catch rates of haddock, whiting, and flatfish, but caused a marked decrease in the catch rate of commercially valuable anglerfish.

Batfishes (Ogcocephalidae) are an understudied, group of marine anglerfishes that are dorsoventrally flattened and have an illicium and esca (terminal lure) used to attract prey. The family contains 10 genera and 75 recognized species from nearly all tropical and subtropical seas. Relationships among these taxa, as well as the position of Ogcocephalidae within Lophiiformes, remain poorly understood with previous studies showing conflicting, and poorly resolved results. The timing of divergence and depth of origination in the water column have also not been explored in any detail. In this study a concatenated nuclear (three genes) and mitochondrial (two genes) dataset was constructed across several anglerfish families to elucidate phylogenetic relationships among all ten batfish genera, to clarify the placement of Ogcocephaloidei within Lophiiformes, and to estimate divergence times using fossil calibrations. An ancestral state reconstruction was also conducted to examine the history of shifts in preferred habitat depths within batfishes. Phylogenetic analyses supported monophyly of each sub-order within Lophiiformes and placed Ogcocephaloidei as the sister group to Antennarioidei. Batfish genera were divided into an Eastern Pacific/Western Atlantic clade and an Indo-Pacific clade; Halieutaea was recovered as the sister group to all other batfishes. Based on divergence time estimations and ancestral state reconstructions of preferred depth, Ogcocephalidae is Eocene in age and originated on the lower continental shelf/upper continental slope (disphotic zone).

Weight–lengthrelationships,weightconversionfactorsandsomaticindicesarepresentedfromadecade (2006 to 2015) for two stocks of Lophius budegassa and L.piscatorius in northern Iberian Atlantic waters (ICES Div. VIIIc–IXa2) and in Celtic Sea, south-western Ireland and Porcupine Bank (Div. VIIb,c,h,j,k). A total of 3298 L.budegassa and 7219 L.piscatorius were sampled from commercial landings and research surveys. Total length (Lt), total weight (Wt), ‘‘commercial’’ weight (Wgl) and ‘‘scientific’’ weight (Wg) were obtained. The parameters (a, b) in the power relationships weight–length for combined sexes in L.budegassa were: 0.020, 2.916; 0.017, 2.929; 0.017, 2.922 for Wt, Wgl and Wg respectively in Div. VIIIc–IXa2;0.025,2.841;0.013,2.984;0.013,2.971inDiv.VIIb,c,h,j,k.ForL.piscatorius:0.025,2.853;0.020, 2.868;0.024,2.861inDiv.VIIIc–IXa2;0.027,2.826;0.023,2.825;0.023,2.816inDiv.VIIb,c,h,j,k.Significant differences between stocks were found in both species. The conversion factors between total and gutted weight in L.budegassa were: 1.186, 1.236 for Wgl and Wg respectively in Div. VIIIc–IXa2; 1.187, 1.233 in Div. VIIb,c,h,j,k. For L.piscatorius: 1.181, 1.241 in Div. VIIIc–IXa2; 1.210, 1.262 in Div. VIIb,c,h,j,k. The parameters can be used in the process of annual assessment of the state of each stock. Gonadosomatic index (GSI), hepatosomatic index (HSI) and Le Cren’s condition factor, indicators of reproductive and nutritional status, were seasonally analyzed and compared between sexes and stocks. Significant better condition and higher GSI and HSI were found in females. In Div. VIIb,c,h,j,k better condition was found for both species and higher GSI for L.piscatorius. The analysis throughout the year of GSI and HSI for L.budegassashowedseasonalityinlivergrowthprevioustospawnandcorroboratedthespawningseason from January to June in VIIIc–IXa2. The parameters obtained were compared with previous ones from these and others Lophiiformes, showing common patterns., SI

14 pages, 7 figures, 2 tables, Reproductive parameters of the white anglerfish (Lophius piscatorius) in the northwestern Mediterranean Sea were studied in 556 specimens collected monthly aboard commercial fishing vessels that were trawling at depths of 12-836 m. The main spawning season occurred from February through June. The size at maturity was estimated to be 48.8 cm in total length (TL) for males, 59.9 cm TL for females, and 51.3 cm TL for both sexes combined. The white anglerfish has group-synchronous oocyte development and determinate fecundity. It is a total spawner (spawns all its eggs once during a spawning season) and has a batch fecundity ranging from 661,647 to 885,214 oocytes, a relative batch fecundity of 66-128 oocytes per gram of female gutted weight, and a potential fecundity with values from 54,717 to 104,506 oocytes per kilogram of female total weight. This study is the first to provide the reproductive biology of white anglerfish in the northwestern Mediterranean Sea and provide valuable information that can be used to improve the stock assessment and ensure proper management of this species

A sexually parasitized female of the deep-sea ceratioid anglerfish Centrophryne spinulosa is described for the first time, bringing the number of ceratioid species known to exhibit sexual parasitism to 24 and the number of ceratioid families to six. The attached pair represents the largest known individuals of both sexes. The extreme and puzzling rarity of parasitized females in some of the best known ceratioid species is discussed. While it has been hypothesized that some ceratioid taxa reproduce solely by temporary male–female attachment, it now seems reasonable to expect the eventual discovery of parasitized females in any of the remaining ceratioid taxa.

Anglerfish (Lophius piscatorius) collected from several locations in the southwestern European waters (from southwest of Ireland to northwest of Spain) were examined for the parasitic copepod Chondracanthus lophii in 2007, 2008 and 2009. The influence of host size, time (season, year) and spatial variables (geographical area, depth, latitude and longitude) on the infestation variability was studied. Zero-altered models (ZAMs) and generalized additive models (GAMs) were used to assess the prevalence and intensity of infection related to the variables studied. The variables which proved to have the greatest effects on the infestation were host size and geographical area, while the impact of variables such as year and season turned out to be less evident. Abundance, prevalence and intensity of C. lophii increased with host size. The highest infestation levels were recorded in the West of Ireland and on the Porcupine Bank, and within these areas the parasite load increased with latitude. Prevalence o...

9 pages, 4 figures, 4 tables, 1 appendix supplementary data https://dx.doi.org/10.1016/j.ecss.2016.03.007.-- This study is a contribution to the project ECOTRANS (CTM2011-26333, Spanish Ministry of Economy and Competiveness, Spain) and to the Master's thesis of NL, The study of the feeding ecology of marine organisms is crucial to understanding their ecological roles and advancing our knowledge of marine ecosystem functioning. The aim of this study was to analyse the trophic ecology of two demersal predator species, black anglerfish (Lophius budegassa) and white anglerfish (L. piscatorius), in the northwestern Mediterranean Sea. Both species are important in the study area due to their high abundance and economic value, but information about their feeding behaviour is scarce. Here, we described the diet composition and ecological role of these two species, investigating whether trophic segregation exists between them and amongst fish of different sizes. In addition, by using experimental survey data we described the spatial distribution of both species to help us interpret trophic behaviour patterns. We gathered samples of two different sizes (small individuals of a total length, JN was supported by the Andalucía Talent Hub Program (Andalusian Knowledge Agency, co funded by the European Union's Seventh Framework Program, Marie Skłodowska Curie actions). MC was partially funded by the European Commission through the Marie Curie Career Integration Grant Fellowships – PCIG10-GA-2011-303534 – to the BIOWEB project and by the Spanish National Program Ramon y Cajal. CB and MA-P were supported by predoctoral fellowships of CONICYT-Becas Chile and FPI program of Spanish Ministry of Economy and Competitiveness, respectively.

The white anglerfish (Lophius piscatorius) is a bottom-living and commercially important species for European fisheries (∼38.000 t in Atlantic waters in 2015). Weight-length relationship, weight conversion factors and condition factor for this species are estimated from a decade (2006-2015) in northern Iberian waters (ICES Div. VIIIc-IXa, southern stock) and in Celtic Seas (ICES Div. VIIb,c,h,j,k, northern stock). A total of 7219 white anglerfish were collected from commercial landings and research surveys and the total length (Lt), total weight (Wt), gutted weight with liver (Wgl) and gutted weight (Wg) were obtained. The weight-length relationships for the combined sexes were: Lt = 0.025 Wt2.853; Lt = 0.02 Wgl2.868; Lt = 0.024 Wg2.861 in Div. VIIIc-IXa, and Lt = 0.027 Wt2.826; Lt = 0.023 Wgl2.825; Lt = 0.023 Wg2.816 in Div. VIIb,c,h,j,k. The commercial landings of this species are available in gutted weight, and therefore the conversion factor (total-gutted weights) was also estimated. All these results can be used in the annual assessment of the state of both stocks in the ICES working group. The condition factor was estimated along the year for immature and mature individuals of each sex and it could provide additional information regarding the spawning season. The results are compared to the previously estimated in other studies.

A new species of the deep-sea ceratioid anglerfish genus Himantolophus, long hidden within material identified as H. appelii Clarke, 1878, is described based on 43 female specimens collected in southern waters of all three major oceans of the world. A member of the H. appelii group, it differs from its sister-species, H. appelii, the only other member of the group, in details of escal morphology. The two species are geographically sympatric over much of their range.

A duplex real-time PCR assay based on TaqMan probe technology was developed for the authentication of two commercially important anglerfish species (Lophius budegassa and L. piscatorius). This technique uses the cytochrome oxidase subunit I and allows the unambiguous identification of this species. It is notable for its simplicity, rapidity, highest potential for automation and minor risk of contamination. The TaqMan real-time PCR is currently the most suitable method for screening, allowing the detection of fraudulent or unintentional mislabeling of these species. The method can be applied to all kind of products as fresh, frozen, and precooked products. The developed methodology, which uses two specific primer–probe sets, has been validated and subsequently applied to 40 commercial samples labeled as any anglerfish species in order to determinate whether the species used for their manufacturing correspond to these species. The methodology herein developed is appropriate to clarify questions related with the correct labeling of commercial products, traceability in commercial trade, and fisheries control.

†Sharfia mirabilis, a new genus and species of lophiid anglerfish from the Ypresian of Monte Bolca, northern Italy, is described from a single specimen residing among collections of the Museum national d'Histoire naturelle, Paris. Together with †Lophius brachysomus Agassiz, 1835, known from three or four individuals also from Monte Bolca, †Sharfia mirabilis is the oldest member of the teleost family Lophiidae known to date based on articulated skeletal remains. It possesses several autapomorphic features as well as a unique combination of character states, especially in the structure of the opercular bones, which clearly separate it from all other known lophiiform fishes. Among extant lophiid genera, the new taxon shows perhaps the strongest phenetic resemblance to Sladenia and Lophiodes. †Sharfia mirabilis most likely inhabited inner shelf regions of the central Tethys Sea about 50 Ma, living at moderate depths on soft mud or sand bottoms, much like extant members of the family.

The diversity, abundance and distribution of pelagic fishes from 0-5000 m in the Sargasso Sea, northwestern Atlantic Ocean, were investigated, with primary focus on fishes between 1000-5000 m. A large-volume, fine-mesh (335-μm), discrete-depth sampling system was used to sample the latter strata in 1000-m intervals. Species composition and total biomass of fishes collected in these strata were compared with samples taken 0-1000 m using a smaller midwater trawl. Samples were collected in association with the Census of Marine Zooplankton at-sea DNA-sequencing effort, allowing the determination of genetic barcodes of taxa for which species descriptions do not currently exist (e.g., many male ceratioid anglerfishes). A total of 3965 fish specimens were collected, representing minimally 127 species (84 genera), from 42 families. The bristlemouth, Cyclothone braueri, dominated the catches both above (47%) and below (41%) 1000 m. The Myctophidae and Stomiidae were the most species-rich taxa, while the deep-sea anglerfish suborder Ceratioidei was the most diverse bathypelagic taxon. Thirty species of fish were sequenced and data submitted to GenBank. New Ocean Biogeographic Information System location records for the Saragasso Sea were logged for 84 fish species. Hydrographic data revealed separation of the region into three physical regimes within the top 1000 m (northern, transition, and southern), while the sub-1000 m stratum was fairly homogeneous. Though species richness, abundance, and diversity were highest in the southern Sargasso, diversity indices of whole water column (0-5000 m) samples were not significantly different between regions. Below 1000 m, the 1000-2000 m stratum held the most diverse assemblage across the entire transect, but high diversity was exhibited below 3000 m at two of four stations. Ordination discriminated 13 pelagic fish assemblages, with these related to depth far more than region. Geometric abundance class analysis revealed profound differences in relative species abundances between the meso- and bathypelagic zones with the former demonstrating a much higher percentage of common species. This finding tracks the hydrographic patterns observed: increased stability in the bathypelagic zone favors increased numbers of rare species relative to the mesopelagic zone, where hydrographic complexity favors higher numbers of common species.

A new genus and species of anglerfish, Dibrachichthys melanurus, of the antennarioid family Tetrabrachiidae, is described on the basis of 42 specimens collected in near-shore coastal waters of Queensland, Northern Territory, Western Australia, and the Aru Islands, southeastern Indonesia. It differs most strikingly from its sister species, Tetrabrachium ocellatum, the only previously described tetrabrachiid, in having the pectoral fin entire, rather than having the rays divided into two distinct sections, a feature that was heretofore diagnostic for the family. The new taxon is diagnosed, described, and compared osteologically with its sister taxon using high-resolution, X-ray computed tomography.

This study provides a contribution to the knowledge on distribution, population structure and dynamics of Lophius budegassa in the North-western Ionian Sea (Eastern Mediterranean Sea) as well as an estimation of its exploitation condition. Data were collected during 23 trawl surveys carried out in spring-summer and autumn from June 1995 to November–December 2006. Specimens were collected between 13 and 745 m. No significant trends were shown in the fluctuation of the abundance indices throughout the study period, indicating a stable condition in the stock distributed from the shelf to the upper slope. A decreasing trend with depth was only shown in the density index values. The greatest biomass values were recorded in autumn and the highest incidence of juveniles (TL The mortality rate (Z) calculated using the growth parameters derived from the direct age estimation varied between the annual value of 0.54 in 2001 and that of 0.87 in 2000 and 2003. The natural mortality rate (M) was computed using different approaches. In females it was between 0.24 and 0.23 while in males was between 0.25 and 0.24. Adopting two sets of growth parameters for sex combined and the M value of 0.22 and the value of 0.39, two scenarios for fishing mortality rates and exploitation ratios were obtained. Although, the total and fishing mortality rates and exploitation ratios fluctuated throughout the sampling period no significant trends were detected. The E values changed between 0.59 and 0.77 and no significant differences were observed with the two scenarios. A growth overfishing condition was detected for the stock in the North-western Ionian Sea. The exploited stock of L. budegassa in the Ionian Sea mainly consists of juveniles younger than 3–4 years old. Although, spawners are extremely scarce, most probably as a consequence of fishing pressure, the continuity of recruitment seems to be guaranteed by adults distributed in “refuge areas” where trawl fishing does not occur.

Dobby, H., Allan, L., Harding, M., Laurenson, C. H., and McLay, H. A. 2008. Improving the quality of information on Scottish anglerfish fisheries: making use of fishers’ data. – ICES Journal of Marine Science, 65: 1334–1345. In recent years, the International Council for the Exploration of the Sea (ICES) Working Group on the Assessment of Northern Shelf Demersal Stocks has been unable to provide an analytical assessment for anglerfish. One of the reasons for this has been the poor quality of the commercial catch-and-effort data, with ICES and the European Commission’s Scientific, Technical, and Economic Committee for Fisheries (STECF) stressing the need for reliable information on which to base estimates of stock status. In response, and following consultation with the fishing industry, an anglerfish tallybook project was implemented in Scotland as part of a long-term approach to providing better data. Tallybooks are completed on a haul-by-haul basis. Skippers record catches of anglerfish (by size category) and other species where possible, together with information on haul location, duration, and depth. Individual vessel catch rates are calculated and used to provide insights into temporal trends in the stock and the spatial distribution of the fishery. The history of the fishery and management advice are summarized, and an overview of the tallybook project is provided. Catch rates are analysed using a generalized additive modelling approach which incorporates seasonal, annual, spatial, and vessel-dependent effects. The results show increased catch rates between 2006 and 2007.

Johnson, A. K., Richards, R. A., Cullen, D. W., and Sutherland, S. J. 2008. Growth, reproduction, and feeding of large monkfish, Lophius americanus. – ICES Journal of Marine Science, 65: 1306–1315. The American monkfish, Lophius americanus, supports important commercial fisheries in the Northwest Atlantic. Although life history information is available for smaller L. americanus, the biology of large monkfish (>70 cm) is poorly understood because relatively few large fish are caught in standard resource surveys. Between 2006 and 2008, 699 L. americanus of 71–118 cm total length were collected from commercial gillnet fishers operating in the mid-Atlantic Bight (n = 689) and in the Gulf of Maine (n = 10) to investigate growth rates, reproductive biology, and feeding habits of large monkfish. All those collected were mature females ranging in age from 7 to 13 years. Growth was linear at an average annual rate of 7.6 cm. Hepatosomatic indices peaked in February and gonadosomatic indices between February and April. Postovulatory follicles and vitellogenic oocytes were observed in the same ovaries, evidence that monkfish spawn over a protracted period and possibly more than once annually. Food habits were similar to those reported for smaller benthic phase monkfish, but cannibalism was more prevalent in large fish (5.6% frequency of occurrence). Frequencies of feeding and cannibalism were greatest in females in the final stage of oocyte maturation.

This manuscript presents the first results on abundance and distribution of white anglerfish (Lophius piscatorius) from a series of groundfish surveys carried out on the Porcupine Bank. White anglerfish were caught in all trawlable areas, recruits and juveniles mainly from the shallower parts of the bank, around the central mound and closer to the Irish shelf. A strong cohort was manifest in 2001, and it could be tracked over time by age matrices obtained with illicia age–length keys (ALKs) collected during the surveys. However, a mismatch in the cohort analysis suggests that the growth pattern based on illicia underestimates around three of the younger age classes. Using an ALK estimated numerically from a faster growth model, this mismatch disappears, which seems to confirm faster growth. Recruits of the 0-group and adults of age 4 (with the faster growth: ca. ∼57–65 cm) dominated, whereas the intermediate age groups were scarce on the bank. These results and recent findings from tag-and-recapture experiments suggest that white anglerfish move to and from the Porcupine Bank, calling into question the stock boundaries currently accepted for the species in the North Atlantic., Sí

Estimates of Spanish bottom trawl discards of anglerfish Lophius budegassa and Lophius piscatorius in the Northeast Atlantic Ocean are presented. Both species are commercially valuable in ICES Subareas VI and VII, and Divisions VIIIc and IXa. Information was obtained from observers on board during discard-monitoring programmes. Raising by effort, rather than by landings and target species, was used to determine the total annual discards by weight and number, the discard percentage, and the discard length distribution by stock throughout the dataseries. By weight and number, discards varied interannually, ranging from 4 to 600 t (∼28 000–7 000 000 fish) in northern stocks of anglerfish, and from 1 to 100 t (∼20 000–400 000 fish) in southern stocks. The discard percentage for both species and northern and southern stocks therefore ranged between 2 and 76% by number. Length distributions of the discarded anglerfish show that most were juveniles, although the pattern differed in years with high or with low rates of discarding. The number of juveniles caught apparently increased in most areas after 2000. Correlations between the quantities discarded and recruitment indices from French and Irish trawl surveys were found for northern stocks and with Spanish trawl survey indices for southern stocks., Sí

Richards, R. A., Nitschke, P. C., and Sosebee, K. A. 2008. Population biology of monkfish Lophius americanus. – ICES Journal of Marine Science, 65: 1291–1305. This paper provides an overview of the biology of monkfish in US waters of the Northwest Atlantic Ocean using data from resource surveys spanning the period 1948–2007. Monkfish exhibited seasonal onshore–offshore shifts in distribution, migrated out of the southern Mid-Atlantic Bight (MAB) in mid-spring, and re-appeared there in autumn. Sex ratios at length for fish 40–65-cm long were skewed towards males in the southern MAB, but approximated unity elsewhere, suggesting that a portion of the population resides outside sampled areas. Growth was linear at 9.9 cm year−1 and did not differ by region or sex. Maximum observed size was 138 cm for females and 85 cm for males. Length at 50% maturity for males was 35.6 cm (4.1 years old) in the north and 37.9 cm (4.3 years old) in the south; for females 38.8 cm (4.6 years old) in the north and 43.8 cm (4.9 years old) in the south. Ripe females were found in shallow (200 m) water in the south, and in shallow water (

Laurenson, C. H., Dobby, H., and McLay, H. A. 2008. The Lophius budegassa component of monkfish catches in Scottish waters. – ICES Journal of Marine Science, 65: 1346–1349. To date, research efforts on Lophius species in waters around Scotland (ICES Divisions IVa, VIa, and VIb) have focused almost exclusively on Lophius piscatorius. Here, the characteristics and distribution of the Lophius budegassa component of the catch are described using data collected by observers during commercial fishing trips and scientific surveys on chartered commercial fishing vessels between 1998 and 2006. At Rockall Bank (VIb), L. budegassa were rare, just 0.1% of the catch of Lophius spp., whereas west of Scotland (VIa) and around the Shetland Islands (IVa), they made up 18 and 2% of catches, respectively, with greatest prevalence towards the shelf edge. Fish length ranged from 16 to 89 cm with a modal length at 40 cm. Greater proportions of large individuals were recorded around the Shetland Islands than in other parts of the study area. Overall, the sex ratio was 1:1, and lengths at 50% maturity were estimated to be 70.4 cm for females and 49.4 cm for males.

Azevedo, M., Duarte, R., Cardador, F., Sousa, P., Fariña, C., Sampedro, P., Landa, J., and Costas, G. 2008. Application of dynamic factor analysis in the assessment of Iberian anglerfish stocks. – ICES Journal of Marine Science, 65: 1362–1369. Dynamic factor analysis (DFA) was applied to six time-series of catch per unit effort data of the Iberian (ICES Divisions VIIIc and IXa) white anglerfish (Lophius piscatorius) and black anglerfish (L. budegassa). Results showed that grouping the abundance indices reflected the fleet's area of exploitation and fish size selection. Two common trends (CTs) were extracted for each species, capturing the main signal of abundance over time. The white anglerfish was assessed using these CTs as input to the biomass dynamic model currently used in the ICES assessment, to investigate whether the approach would reduce the uncertainty in parameter estimates and related quantities. Using the CTs, bias estimates are lower. The current perception of an overexploited stock is unchanged, but a much lower intrinsic rate of biomass increase was estimated, indicating that the biomass recovery might be much slower. A lower maximum sustainable yield, ∼3600 t, was obtained, and this is more consistent with the historical landings trajectory. The application of DFA to stock assessment of anglerfish, presented here for the first time, can be extended to age-based assessments.

The extensive periodic vertical movements of up to 14 h and 209 m observed in this study for an individual goosefish, Lophius americanus, challenges previous assumptions about the benthic and highly sedentary behavior of the species as well as of other lophiids. Researchers should consider conducting similar data storage tagging studies with other benthic fishes to test assumptions of sedentary behavior.

Reid, D. G., Allen, V. J., Bova, D. J., Jones, E. G., Kynoch, R. J., Peach, K. J., Fernandes, P. G., and Turrell, W. R. 2007. Anglerfish catchability for swept-area abundance estimates in a new survey trawl. – ICES Journal of Marine Science, 64: 1503–1511. In 2005, a new trawl survey was launched in Scotland to estimate anglerfish (Lophius spp.) abundance using swept-area estimates. This required an understanding of the herding of the fish by the gear, particularly in the zone between the doors and wing ends. TV observations at the wing ends and along the sweeps were used to quantify the behavioural reactions of anglerfish. These observations were analysed to develop a gear efficiency estimate. This paper details the construction of the net and the procedures for data collection on the survey. In all, 54 reliable observations of anglerfish were recorded at the groundgear, the wing ends, and along the sweep/bridle combination. Detailed analysis of the recordings showed that all fish in the path of the net were captured, whereas more than half of the fish between the wings and the doors were not. The fish did not appear to herd and many of the encounters with the wires were passive. An individual-based particle-tracking model was constructed to use the behavioural observations to simulate the capture process and generate an efficiency factor. The calculated efficiency factor, based on the behavioural observations, was 1.04, indicating that almost all fish encountering the sweeps and bridles were lost. The implications and suggestions for development of this work are discussed.

A new species of the deep-sea ceratioid anglerfish genus Chaenophryne Regan (Lophiiformes: Oneirodidae), Chaenophryne quasiramifera, is described on the basis of two female specimens collected from the Nasca Ridge and Peru-Chile Trench in the Eastern Tropical Pacific Ocean. The new form is distinguished from its congeners by a combination of features that includes escal morphology, illicium length, and jaw-tooth and fin-ray counts. The new species is diagnosed and described, and a revised key to the species is provided.

7 pages, 4 figures, In the Mediterranean Sea, anglerfish Lophius budegassa and Lophius piscatorius support an important fishery, and landings have increased in recent years. These species are infected by the microsporean Spraguea lophii, a parasite that infects their nervous system giving rise to multiple cysts. Due to the high value of these fish and conspicuous nature of the infection, we determined the apparent prevalence of this parasite in both Lophius spp. Specimens were obtained from commercial catches along the NW Mediterranean Sea during 2013. The parasite was observed in the nerves from the peripheral nervous system of the individuals and was detected at the prevalence of 69.2 % (202/292) and 100 % (58/58) in L. budegassa and L. piscatorius, respectively. Nonsignificant differences were noted between sexes of L. budegassa (χ2=0.683; p=0.409), although a positive correlation was noted between host size and prevalence (χ2=6.134; p=0.013). During the sampling, two specimens of L. budegassa with atypical morphological characteristics, pigment anomalies and blindness and infected with S. lophii xenomas were described, C. Barría was supported by a predoctoral fellowship CONICYT-Becas Chile

The deep-sea ceratioid anglerfish genus Acentrophryne is revised on the basis of all known material. Two species are recognized: the type species Acentrophryne longidens, represented by two specimens collected in the Gulf of Panama and from off the Pacific coast of Costa Rica and a new species described here on the basis of three specimens, all from off Peru. The new species differs from A. longidens in having a much longer distal escal appendage, a longer illicium, a narrower head, and fewer pectoral-fin rays. Diagnoses and descriptions are given for all taxa and a key to the species is provided.

The diet of anglerfish (Lophius piscatorius), based on the analysis of stomach contents, was investigated in the Shetland Islands. Samples were obtained during trawling for sandeel (Ammodytidae species) and demersal trawling when mainly whitefish (gadoids) are targeted. This allowed the diets of samples collected from different areas and at different times to be compared. The diets in different length groups were also compared and niche breadth investigated.A wide range of prey types, mainly fish, were recorded but the main prey was Norway pout (Trisopterus esmarkii) and lesser sandeel (Ammodytes marinus). Diet composition varied seasonally. In samples collected during whitefish trawling the occurrence of empty stomachs decreased from the first to the third quarters and generally increased with increasing anglerfish size. Empty stomachs occurred less frequently in samples collected from areas where sandeel fishing occurred compared to areas where whitefish trawling occurred.

A new species of the deep-sea ceratioid anglerfish genus Lasiognathus Regan (family Thaumatichthyidae) is described from a single female specimen collected in the eastern north Atlantic Ocean off Madeira. It is most similar to Lasiognathus saccostoma Regan but differs from this species and from its remaining congeners, Lasiognathus beebei Regan and Trewavas, Lasiognathus waltoni Nolan and Rosenblatt, and Lasiognathus intermedius Bertelsen and Pietsch, in having only two bony hooks in the esca. The new species is diagnosed and described, and a revised key to the species is provided.

A new species of the antennariid anglerfish genus Lophiocharon, L. hutchinsi, is described on the basis of nine specimens collected from Western Australia, Northern Territory, and Queensland, and from the Aru Islands, Indonesia. It differs from its congeners in having a combination of features that includes a reduced esca, scarcely, if at all, differentiated from the illicium, and a relatively short illicium covered from base to tip with small dermal spinules.

The deep-sea ceratioid anglerfish genus Bufoceratias Whitley is revised on the basis of all known material. Three species are recognized: Bufoceratias wedli (Pietschmann), now represented by 69 specimens collected from both sides of the Atlantic Ocean; Bufoceratias thele (Uwate), 11 specimens from the western Pacific; and a new species, Bufoceratias shaoi, described on the basis of four specimens from the Western Indian and Western Pacific oceans. The new species differs from its congeners by having a short illicium and an unusually large and morphologically complex esca. Diagnoses and descriptions are given for all taxa and a revised key to the species of the genus is provided. Diceratiids are found in all three major oceans of the world, but they are conspicuously absent from the eastern Pacific. In contrast to the midwater life style generally assumed for most ceratioids, at least some diceratiids, especially larger individuals, are associated with the bottom.

We present a method based on generalised linear models fitted to CPUE data to quantify the changes in fishing power in a fleet targeting a particular species. Changes in the fleet's fishing power are differentiated from variations in population abundance through the use of an abundance index estimated from the CPUE of an index vessel catching the species as by-catch. Observed inter-vessel differences in efficiency are then explained by vessel characteristics such as gear used, engine power, length of headline and ground rope, availability of GPS and skipper skills. The application of the method to the French bottom-trawlers targeting anglerfish in the Bay of Biscay and in the Celtic Sea during the period 1983–1998 reveals that fishing gear (twin or simple trawls) and engine power are the most important variables for explaining differences in fishing power. Nous présentons une méthode basée sur l'utilisation de modèles linéaires généralisés ajustés à des données de CPUE pour quantifier les changements de puissances de pêche dans une flottille ciblant une espèce particulière. Les changements de puissance de pêche sont distingués des variations d'abondance de la population en utilisant un indice d'abondance estimé à partir des CPUE d'un bateau témoin capturant cette espèce de manière accessoire. Les différences d'efficacité observées entre les bateaux sont ensuite expliquées par les caractéristiques techniques telles que l'engin utilisé, la puissance motrice, la longueur de la corde de dos, le bourrelet, la possession d'un GPS et l'expérience du capitaine. L'application de la méthode aux chalutiers de fond français ciblant la baudroie dans le golfe de Gascogne et la mer Celtique sur la période 1983–1998 a montré que la puissance motrice et l'engin de pêche (chalut jumeau ou simple) étaient les facteurs qui expliquaient le plus les différences de puissance de pêche.

Predicting the occurrence of economically important demersal fish in a multispecies marine environment can be of considerable value to fisheries management and protection of biodi- versity. Here, 2 predictive modelling principles were utilised, artificial neural network (ANN) and discriminant function analysis (DFA), to develop presence/absence models for 3 species (anglerfish Lophius budegassa; hake Merluccius merluccius; red mullet Mullus barbatus) in the Mediterranean Sea. ANN-based models of demersal fish distribution outperformed conventional models and attained better recognition and prediction performance. Results indicated the ability of ANN's to pre- dict presence more accurately than DFA when tested against independent field data. More precisely, sensitivity values obtained using DFA were 62.1% for anglerfish, 5.8% for hake and 59.8% for red mullet whereas using ANN were 75, 71 and 72.9% respectively. The accuracy of test data was 79.6% for anglerfish, 49.5% for hake and 83.3% for red mullet using DFA and 83.7, 83.3 and 85.6% respec- tively using a back-propagation ANN. After learning from a set of selected patterns, the neural net- work (NN) models displayed a relatively high demersal fish classification accuracy, which was con- sistent with present understanding of the aggregating effects of the examined variables on these species' distribution. Predicting presence or absence was found to be easier for red mullet and anglerfish than for hake. The present results also suggested that the main processes modulating the occurrence of anglerfish, hake and red mullet in the NE Mediterranean Sea can be approximated by linear functions only to a limited extent. Due to their ability to mimic non-linear systems, ANNs proved far more effective in modelling the distribution of these species in the marine ecosystem. The main results and the ANN potential to predict suitable habitat profiles and structural characteristics of species assemblages are discussed.

The consequences for food-web structure of protecting marine communities from trawling have been little explored. We investigated the Gulf of Castellammare, northwest Sicily, where a trawl ban initiated in 1989 has led to great increases in the biomass of some target species. Using stable isotopes of carbon and nitrogen, our objectives were to see if mean trophic level and omnivory had increased after the ban in three of the most common fishery-target species, namely, the anglerfish Lophius budegassa, Mediterranean hake Merluccius merluccius, and red mullet Mullus barbatus. We compared size data from before and after the fishery closure, but we also compared recently derived data from outside and inside the closed area. In all three species δ13C and δ15N were found to differ markedly depending on fish size. δ13C was found to decrease in L. budegassa and Merluccius merluccius but increase in Mullus barbatus with increasing fish length. δ15N increased in all three species, and this was thought to reflect feeding at increasingly higher trophic levels during the animals' lives. Mean length, and therefore δ15N-derived trophic level, increased after the trawl ban only in the anglerfish L. budegassa. Based on δ13C and δ15N data, none of the species became more or less omnivorous after the ban. After 9 years of no trawling, increases in numerical abundance were not accompanied by substantial size-related trophodynamic shifts in any of the three species of fish studied.

Discards of the French trawler fleet operating in the Celtic Sea in 1997 were studied. Twenty-six trips, representing 0.8% of the total fishing effort, were sampled. This fleet consists of three metiers, benthic trawlers, Gadoid trawlers and Nephrops trawlers. The fleet discarded an estimated 30 000 tons of animals in 1997, while landing 63 000 tons. The total quantity discarded did not differ among metiers, but the species composition of discards did. Benthic trawlers discarded mainly by-catch species, whereas Gadoid and Nephrops trawlers discarded primarily their target species. Whiting, megrim, Nephrops and hake were discarded in larger numbers than landed. Hence discards should be taken into account in catch-based assessments. However, discards were found to be highly variable between trips and between years. In addition, no reliable auxiliary variable could be found when various factors were investigated to explain the quantities of commercial species discarded. The only explanatory factor valid for any species was the smallest size of that species in the catch. Hence there is a need for regular sampling of discards.

Microincrements in the lapilli otoliths of Lophius piscatorius L. were used to validate the age of fish

Although the anglerfish Lophius piscatorius is now a species of major commercial importance, our understanding of its basic biology is far from complete. Here, the early life history of L. piscatorius is investigated by otolith daily increment analysis, the application of a particle tracking model and an examination of the geographical distribution of pelagic and demersal anglerfish. Otolith incremental analysis indicates that the pelagic phase is relatively long (ca. 120 days) and growth during the first year of life is rapid. A particle tracking model predicts that pelagic post larvae of known age caught west of the Outer Hebrides could originate from the shelf edge west of Ireland, the Rockall Plateau and the northern perimeter of the North Sea, whereas those caught in the northern North Sea are likely to originate from the western edge of the Norwegian Deep and the shelf edge west and north of Scotland. The model also predicts that a large proportion of the young anglerfish originating from a spawning area located west of the Outer Hebrides will enter the North Sea and that although most of the spawning products originating at Rockall will recruit to the Rockall Plateau some may be transported northwest and some to the northern perimeter of the North Sea. The distribution of the demersal stages suggests that L. piscatorius spawns in deep water, the transition from the pelagic to the demersal phase takes place in relatively shallow water and most recruits enter the North Sea from the north and west. The finding that some juveniles may settle on the seabed hundreds of kilometres from the spawning grounds has major implications for the effective management of the fishery.

A microsatellite-enriched genomic library was obtained using individuals of the blackanglerfish ( Lophius budegassa ) and eight polymorphic microsatellites were successfullyoptimized. The genetic analysis of 50 black anglerfish individuals captured in the Cantabriancoasts revealed high polymorphism with a mean of number of alleles per locus of N a = 10.5(5–28 alleles) and a mean expected heterozygosity of 0.740 (0.521–0.962). This microsatelliteset was also functional with a sample from the white anglerfish ( Lophius piscatorious )showing a high polymorphism. Keywords : anglerfish, cross-amplification, enriched library, Lophiidae, microsatellites Received 7 December 2005; revision accepted 22 January 2006 The two anglerfish species ( Lophius budegassa Spinola, 1807and Lophius piscatorius Linnaeus, 1758) are among themost valuable bottom fisheries in western and southernEuropean waters. However, in these species, the levels ofvariability observed at protein-coding loci are very low,and in the polymorphic loci described, the frequencies ofthe most common alleles are close to 0.9 (Crozier 1987,1988; Leslie & Grant 1990). In this situation, it does notseem that this type of markers can contribute in thestocks or populations discrimination in this species. To ourknowledge only one previous report exists in which a setof microsatellites have been reported for Lophiidae fishand they showed only moderate levels of genetic variation(mean

The papers of this thesis are not available in Munin: 1. Ofstad, L.H., Pedersen, T., Angus, C.H., and Steingrund, P.: 'Age and growth of anglerfish (Lophius piscatorius) in Faroese waters', Fisheries Research (2013), vol.139:51–60. Available at http://dx.doi.org/10.1016/j.fishres.2012.05.011 2. Ofstad, L.H., Pedersen, T., and Steingrund, P.: 'Maturation, reproduction and early life history of anglerfish Lophius piscatorius in Faroese waters' (manuscript) 3. Ofstad, L.H., Steingrund, P., and Pedersen, T.: 'Seasonal offshore-onshore migration and distribution of anglerfish Lophius piscatorius in Faroese waters' (manuscript) 4. Ofstad, L.H., Steingrund, P., and Pedersen, T.: 'Feeding ecology of anglerfish Lophius piscatorius in Faroese waters' (manuscript) Anglerfish Lophius piscatorius has during the last two decades become a highly exploited resource and is now one of the five most economically important demersal fish species in the Faroese fishery. Despite this, there is at present little information available on the population status of anglerfish in Faroese waters. The main aim of this study is to increase the biological knowledge of anglerfish and to perform an assessment of the stock in order to evaluate the sustainability of the anglerfish fishery and to investigate trophic interactions between anglerfish and other commercially important demersal fish species. Anglerfish illicia, the first fin ray, were used for age reading. The age determinations were validated and concluded to be useful in an age-based assessment because the growth rates were consistent with length frequency and mark-recapture analyses. Anglerfish have a very high growth rate during their first year of life, compared with the older ages. Males mature at a lower length and younger age than females. The L50 for males and females was 58 cm and 84 cm, respectively, corresponding to an age of around four years for males and seven years for females. Observations of spawning males and females, egg-ribbons and pelagic anglerfish larvae revealed that anglerfish have a prolonged spawning season, which peaks from February to April. In addition, observations showed that there are at least two local spawning areas, one southwest of the Faroe Plateau and one in the Faroe Bank area. Large anglerfish tagged with data storage tags and conventional tags showed a seasonal offshore-onshore migration. They migrated to shallow depths in summer to feed and to deeper waters in winter, presumably to spawn. Anglerfish performed vertical movements up into the water column, and were most active in these vertical movements during the winter time and during the nights, and light intensity seemed to trigger the migrations. Anglerfish distribution was temperature dependent, since anglerfish generally preferred temperatures warmer than 4ºC, usually between 6.5–11ºC. This may explain why anglerfish were distributed deeper west of the Faroe Bank area compared to the Faroe Plateau, which is surrounded by cold water deeper than approximately 500 m. Anglerfish in Faroese waters preyed on a variety of food items. They were generally eating fish and the most important prey species in terms of numbers were Norway pout and blue whiting, whereas cod and haddock contributed most in weight. Annual consumption by anglerfish on commercially important demersal species, such as cod, haddock and saithe, was estimated to correspond to 33, 19 and 2% of the landings and to 75, 20 and 2% of biomass losses due to natural mortality, respectively. Even with this high cod consumption by anglerfish, cod cannibalism and fishing mortality still have greater impact on the cod stock dynamics than predation by anglerfish. The annual biomass loss of anglerfish due to cannibalism was estimated to nearly 15% of the annual loss due to natural mortality. Anglerfish in Faroese waters may be regarded as a separate stock because all life stages are found in the area, local spawning area, seasonal offshore-onshore migration on the Faroe Plateau, together with insignificant emigration/immigration (< 5%). An age-based stock assessment of anglerfish in Faroese waters for the period 1999–2011 showed that the stock biomass ranged between 9000 and 19000 t with a peak in 2004–2005 and the fishing mortality for age 3–8 varied between 0.2 and 0.5 year-1. The yield per recruit curve indicated that the stock was slightly growth overfished. Decreasing the fishing mortality could potentially increase the yield per recruit by around 10% leading to a 50% higher equilibrium biomass of anglerfish. No clear stock-recruitment relationship was found. On the other hand, anglerfish year-class strength was correlated with environmental variables, such as sandeel abundance. Hence, the rather short time series of anglerfish year-class strength provides little or no evidence of recruitment overfishing. It is recommended that stock assessments should be performed on an annual basis, allowing managers to react timely when there are signs of overfishing or recruitment failure due to natural or fishery causes.

12 pages, 6 figures, 2 tables, Gonadal morphology and reproductive biology of the Black Anglerfish (Lophius budegassa) were studied by examining 4410 specimens collected between June 2007 and December 2010 in the northwestern Mediterranean Sea. Ovaries and testes presented traits common among fishes of the order Lophiiformes. Spawning occurred between November and March. Size at first maturity (L50) was 33.4 cm in total length (TL) for males and 48.2 cm TL for females. Black Anglerfish is a total spawner with group-synchronous oocyte development and determinate fecundity. Fecundity values ranged from 87,569 to 398,986 oocytes, and mean potential fecundity was estimated at 78,929 (standard error of the mean [SE] 13,648) oocytes per kilogram of mature female. This study provides the first description of the presence of 2–3 eggs sharing the same chamber and a semicystic type of spermatogenesis for Black Anglerfish. This new information allows for a better understanding of Black Anglerfish reproduction— knowledge that will be useful for the assessment and management of this species, We thank the crews of the fi shing vessels Avi Pau, Estel. lada, Germans Félix, San Benito, and Port de Roses for their collaboration during sampling. We also recognize M. Baeta and L. Martínez for their help with data collection; S. Torres, R. Sánchez, and I. Salvo for their assistance with histological and fecundity analyses; and A. Ospina for development of the study area map. We appreciate M. Casadevall and M. Muñoz for their valuable comments about male reproduction. Special thanks go to C. Vestfals for editorial help. This study was conducted within the project, Monitoratge dels recursos pesquers i marisquers al litoral català (Direcció General de Pesca i Afers Marítims, Generalitat de Catalunya). V. Tuset is a scientist of CSIC within the modality JAE-Postdoc of Programme Junta para la Ampliación de Estudios cofunded by the European Social Foundation

The glandular epithelium of both escae and caruncles originates from a solid, branched ingrowth of epidermal cells from the distal surface of the bulb-shaped light gland primordia in the larva. The lumina within the glandular epithelium appear to originate by the breakdown of the central cells within the solid mass of epithelial cells. An epithelium-lined duct connecting the central glandular lumina with the distal surface of the bulb-shaped primordium was seen only in sections of the posterior esca. This suggests that the intraglandular lumina are formed before the duct to the surface, which then develops within an initially solid strand of cells.

Melanocetus johnsoni (Teleostei:Melanocetidae), a bathypelagic marine sit-and-wait predatory fish captured off Hawaii, has an average aerobic metabolism of 0.486 μmol OZ g −1 h',a rate much lower than that of more active species from similar depths but similar to that of other sit-and-wait predators. Larger individuals have a lower mass-specific metabolic rate than do small ones (the slope of the allometric relationship between wet mass and mass-specific metabolism is -0.46). This species, a resident of the oxygen minimum layer, is capable of regulating its oxygen consumption down to the lowest oxygen pressures encountered in its environment off Hawaii, and can also survive for hours under severely hypoxic or anaerobic conditions.