On the metamorphosis of the visual pigments of Anguilla anguilla (L.)

The retinae of all the species of deep-sea fish which have been studied have been shown to contain golden coloured pigments, chrysopsins, which are especially suited to the light found in their natural environment (Denton & Warren, 1957; Munz, 1958). Amongst fish caught in shallow coastal waters this characteristic colour of retinal pigment is found only in the conger eel Conger conger (by Denton & Walker, 1958), and amongst freshwater fish only in the silver eel Anguilla anguilla (by Carlisle & Denton, 1957, referred to by Denton & Warren, 1957). Both these fish are species of Apodes, a group of which the vast majority of species are deep-water forms. Both species, more- over, begin their life in the deep sea and return to it again when mature to spawn and may therefore, in one sense, be regarded as deep-sea fish. Since immature conger eels in shallow coastal waters already have a retinal pigment characteristic of a deep-sea fish, it seems very unlikely that on returning to deep water they would change away from the deep-sea form which they already possess. It is probable therefore that the conger retains a deep-sea form of retinal pigment throughout the whole of its life.

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Diet of a deep-sea fish, Hoplostethus mediterraneus, from the south coast of Portugal

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531540200557x ◽

2002 ◽

Vol 82 (2) ◽

pp. 351-352 ◽

Cited By ~ 6

Author(s):

C. Pais

Keyword(s):

Deep Water ◽

Deep Sea ◽

Prey Species ◽

South Coast ◽

The South ◽

Coastal Fisheries ◽

Meganyctiphanes Norvegica ◽

By Catch ◽

Sea Fish

The beryciform fish Hoplostethus mediterraneus is a species discarded from the southern Portuguese coastal fisheries. It is taken as by-catch by deep water trawls, at depths of between 234 m and 618 m. This species is a benthopelagic feeder, preying mainly on crustaceans. The dominant prey species encountered were the euphausid Meganyctiphanes norvegica and the amphipod Anilocra physodes. It seems that H. mediterraneus is an opportunistic rather than a selective feeder.

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The visual pigment of the conger eel

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1958.0017 ◽

1958 ◽

Vol 148 (931) ◽

pp. 257-269 ◽

Cited By ~ 23

Keyword(s):

Deep Sea ◽

Visual Pigment ◽

Internal Limiting Membrane ◽

Absorption Curve ◽

Spectral Absorption ◽

New Methods ◽

Absorption Of Light ◽

Conger Eel ◽

Sea Fish ◽

Conger Conger

New methods of studying the spectral absorption of intact retinae are described. Using these methods the retina of Conger conger (L.) has been studied and the retinal spectral absorption curves are compared with those obtained on retinal extracts made with digitonin solution. The retina of the conger like that of deep-sea fish is golden in colour, its absorption curve being similar in shape to that of frog rhodopsin but with its maximum displaced about 16 m µ towards the blue end of the spectrum. The absorption curve of unbleached retinae is displaced about 4 m µ towards the red end of the spectrum from the absorption curve of unbleached retinal extract, but, when an estimated correction for possible yellow impurities in the extract is made, this displacement is only one of 2 m µ . The change in optical density of the dark-adapted retina on bleaching with strong white light is 0.6 at λ = 484 m µ : this probably represents a retinal density for unbleached pigment of about 0.8. The visual pigment in the intact retina is approximately twice as effective as simple calculations based on extracts would predict. The absorption of light by the retina is dominated by the principal photosensitive pigment, whilst the screening of the rods, due to the absorption of light by the layers of retina lying between the rods and the internal limiting membrane, is trivial.

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Deep-sea Echinoderidae (Kinorhyncha: Cyclorhagida) from the Northwest Pacific

European Journal of Taxonomy ◽

10.5852/ejt.2018.456 ◽

2018 ◽

Cited By ~ 1

Author(s):

Martin V. Sørensen ◽

Melissa Rohal ◽

David Thistle

Keyword(s):

New Species ◽

Coastal Waters ◽

Deep Sea ◽

Great Depth ◽

Northwest Pacific ◽

Depth Range ◽

Continental Rise ◽

Coastal Species ◽

Pacific Species ◽

Shallow Coastal Waters

The bathyal kinorhynch fauna along the Northwest American continental rise is explored, with emphasis on species of Echinoderidae Zelinka, 1894. Seven species of Echinoderes Claparède, 1863 are described as new to science: E. anniae sp. nov., E. dubiosus sp. nov., E. hamiltonorum sp. nov., E. hviidarum sp. nov., E. juliae sp. nov., E. lupherorum sp. nov. and E. yamasakii sp. nov. Three known species, Echinoderes hakaiensis Herranz, Yangel & Leander, 2017, E. cf. unispinosus Yamasaki, Neuhaus & George, 2018 and Fissuroderes higginsi Neuhaus & Blasche, 2006, are reported. The numerous new species indicate that the deep-sea still holds a great, undiscovered diversity of kinorhynchs, and that Echinoderes, as is also the case in more shallow, coastal waters, represents an important component of the deep-sea kinorhynch fauna. The presence of E. hakaiensis in the deep-sea sediments demonstrates that the species may occur at a great depth range, and suggests that depth may play a less important role for the distribution of some kinorhynch species. The finding of the Northeast Atlantic species E. cf. unispinosus and the Southwest Pacific species Fissuroderes higginsi could indicate that kinorhynch species in the deep-sea may cover considerably larger distributional ranges than is assumed for coastal species of Echinoderidae.

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Distribution patterns of deep-sea fish and benthic invertebrates from trawlable grounds of the Hatton Bank, north-east Atlantic: effects of deep-sea bottom trawling

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531541200015x ◽

2012 ◽

Vol 92 (7) ◽

pp. 1509-1524 ◽

Cited By ~ 14

Author(s):

P. Durán Muñoz ◽

M. Sayago-Gil ◽

T. Patrocinio ◽

M. González-Porto ◽

F. J. Murillo ◽

...

Keyword(s):

Deep Water ◽

Benthic Invertebrates ◽

Deep Sea ◽

Cold Water ◽

East Atlantic ◽

Bottom Trawling ◽

North East ◽

Western Flank ◽

Sea Bottom ◽

Sea Fish

Distributions of deep-sea fish, benthic invertebrates and the effects of deep-sea bottom trawling were studied based on data collected in 2005 from a joint collaboration survey undertaken between the Spanish Institute of Oceanography and a deep-sea trawler on the Hatton Bank (north-east Atlantic). A total of 163 valid bottom trawl hauls (600–1600 m) were analysed. The main trawlable grounds were located on the sedimentary seabed of the western flank of the bank (Hatton Drift). Grenadiers and smoothheads were predominant in the trawl catches (67% and 11.8% by weight respectively). Both species were abundant along the western flank. Deep-water sharks accounted for 7.4% of weight, and were abundant along the south-eastern slopes. Chimerids, lotids, morids and other deep-sea species were also taken as by-catch. Grenadiers and deep-water sharks dominated the discards. By-catches of cold-water corals were generally associated with the rocky outcrop and were more abundant at the top of the bank. Abundant by-catches of large sponges, characteristic of sponge-dominated biotopes, were taken from the eastern flank.

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Deep-sea fish assemblages (300-2100 m) in the eastern Pacific off northern Mexico

Marine Ecology Progress Series ◽

10.3354/meps12502 ◽

2018 ◽

Vol 592 ◽

pp. 225-242 ◽

Cited By ~ 5

Author(s):

E Cruz-Acevedo ◽

N Tolimieri ◽

H Aguirre-Villaseñor

Keyword(s):

Deep Sea ◽

Fish Assemblages ◽

Eastern Pacific ◽

Northern Mexico ◽

Sea Fish

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THE NUMBER AND QUALITATIVE CHARACTERISTICS OF FRY FISH IN SHALLOW COASTAL WATERS OF THE VOLGA IN THE SUMMER-AUTUMN PERIOD OF 2012

VESTNIK OF ASTRAKHAN STATE TECHNICAL UNIVERSITY SERIES FISHING INDUSTRY ◽

10.24143/2073-5529-2017-3-65-73 ◽

2017 ◽

pp. 65-73

Author(s):

Edward Vladimirovich Nikitin

Keyword(s):

Fish Species ◽

Coastal Waters ◽

Caspian Sea ◽

The Caspian Sea ◽

Volga River ◽

Commercial Fish ◽

Autumn Period ◽

Fish Juveniles ◽

Qualitative Characteristics ◽

Shallow Coastal Waters

Shallow coastal waters of the Volga river is a flooded feeding area for fish juveniles of nonmigratory fish species. There takes place annual downstream migration of fluvial anadromous fish species from spawning grounds of the Volga river to the Northern Caspian Sea. The most important factors determining the number and qualitative characteristics of fry fishes are the level of the Caspian Sea (currently having a tendency to the lowering), hydrological and thermal regimes of the Volga river. Researches were carried out in definite periods of time. In the summer-autumn period of 2012 fry fishes were presented by 19 species (13 of them were commercial species), which belonged to 9 families. The article gives data on all the commercial fish species. In the first decade of July the maximum number of fry fish was registered in the western part of the Volga outfall offshore - in box 247 (19.86 mln specimens/km2), in the eastern part - in box 142 (20.4 mln specimens/km2). The most populous were roach, red-eye, silver bream and bream; size-weight characteristics were better in the areas remoted from the Volga delta. In the third decade of July the quantitative indicators of fry fish on these areas decreased, size-weight characteristics greatly increased. In the second decade of October in the western part of the seaside there were registered increased pre-wintering concentrations of fish juveniles, their qualitative indicators increased, which is evidence to favorable feeding conditions in 2012.

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ANALYSIS OF THE FUNCTIONING OF MARINE ECOSYSTEMS ON CHANGING THE PARAMETERS OF THE BIOLUMINESCENCE FIELD ON THE CRIMEAN BLACK SEA SHELF

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b43168bfc21 ◽

2017 ◽

Author(s):

Svetlana Rubtsova ◽

Natalya Lyamina ◽

Aleksey Lyamin ◽

...

Keyword(s):

Black Sea ◽

Field Intensity ◽

Deep Water ◽

Coastal Waters ◽

Integrated Management ◽

Abiotic Factors ◽

Environmental Safety ◽

The Black Sea ◽

Intensity Increase ◽

First Time

The concept of a new approach to environmental assessment is offered in the system of integrated management of the resource and environmental safety of the coastal area of the Black Sea. The studies of the season and daily changeability in the bioluminescence field in the Sevastopol coastal waters has been conducted. For the first time considerable differences in the bioluminescence field seasonal changes in the surface and deep water layers and the reasons conditioning this phenomenon have been shown, using a method of multidimensional statistical analysis. The bioluminescence field vertical profile change in the Black sea coastal waters in the autumn period at night has been studied. It has been shown that according to the character of bioluminescence parameters dynamics a water column can be divided into layers: upper (0 – 35 m) and deep water (36 – 60 m). It has been revealed that life rhythms of the plankton community are the main reason for the bioluminescence field intensity variability. It has been revealed that 14-hour periodicity of the bioluminescence field is related to the changes in light and its variations with 2,5…4,5 hours are conditioned by planktonts endogenous daily rhythms. And here biotic factors effect mostly periodicity of the bioluminescence field intensity increase and fall down at the dark time of the day. Abiotic factors are of less importance in circadian rhythmic of the bioluminescence field in the neritic zone.

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Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽

10.3390/biology10060522 ◽

2021 ◽

Vol 10 (6) ◽

pp. 522

Author(s):

Régis Santos ◽

Wendell Medeiros-Leal ◽

Osman Crespo ◽

Ana Novoa-Pabon ◽

Mário Pinho

Keyword(s):

Population Structure ◽

Life History ◽

Deep Sea ◽

Management Strategies ◽

Size Composition ◽

Large Size ◽

The Common ◽

Fishing Impacts ◽

Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

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Preliminary observations on abundance and distribution of fish fauna in a canyon of the Bay of Biscay (ICES Division 8c)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315420001265 ◽

2021 ◽

pp. 1-10

Author(s):

G. Diez ◽

L. Arregi ◽

M. Basterretxea ◽

E. Cuende ◽

I. Oyarzabal

Keyword(s):

Deep Sea ◽

Basque Country ◽

Fish Fauna ◽

Fishing Effort ◽

Fishing Gear ◽

Clear Trend ◽

Depth Ranges ◽

Abundance And Distribution ◽

Sea Fish ◽

Distribution Of Fish

Abstract The changes in abundance and biodiversity of deep-sea fish fauna are described based on an annual deep-water longline survey with data collected during the period 2015–2019 in the Basque Country continental Slope (ICES Division 8c). The sampling scheme included hauls in four 400 m strata, from 650–2250 m deep. The DST sensors installed in the main line have allowed us to set an accurate soak time for each haul, and they were used to calculate fishing effort and CPUE by haul. The catchability of the fishing gear indicated that 15% of the total hooks deployed in the five-year period were able to fish, and that the bottom longline was very effective in fishing a wide number of different species in all depth ranges. The fishing gear caught 14 different species of sharks (13 deepwater and one pelagic), two chimaeras and nine teleosts. The abundance and biomass registered on the hooks attached to the bottom were between three and four times higher than in the floating sections, and the highest CPUE and biomass were recorded between 1051–1450 m, from 2015 to 2017, and in the 1451–1850 m strata, but they do not show any clear trend throughout the five years of the series.

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