Interannual variability of diet composition and prey preference of larval redfish (Sebastes spp.) in the Gulf of St. Lawrence

Abstract Spatiotemporal overlap between fish larvae and their planktonic prey is an important source of recruitment variability. Over the past decade, one species of redfish, Sebastes mentella, from the Gulf of St. Lawrence (GSL) produced multiple strong cohorts following decades of low recruitment, which has generated strong interest in identifying potential drivers of larval survival. The present study provides the first detailed, multi-year assessment of larval redfish (Sebastes spp.) trophodynamics. Interannual variability in larval redfish diet composition and prey selectivity was assessed using high-resolution prey identification of larval gut contents and in situ prey fields. Eggs from the calanoid copepod Calanus finmarchicus represented the most frequently consumed prey in 3 of the 4 collection years, and contributed the largest proportion of carbon ingested by redfish larvae in all years. The high consumption of C. finmarchicus eggs by larvae, combined with evidence of positive selection for this taxon in some years, supports the hypothesis of a strong trophic link between larval redfish and a key calanoid copepod in the GSL ecosystem. Our results indicate that future efforts investigating GSL redfish recruitment processes should consider environment-driven variability in the reproductive phenology and abundance of C. finmarchicus.

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Food and Inferred Feeding Behavior of Northern Sand Lance (Ammodytes dubius)

Journal of the Fisheries Research Board of Canada ◽

10.1139/f73-075 ◽

1973 ◽

Vol 30 (3) ◽

pp. 451-454 ◽

Cited By ~ 11

Author(s):

J. S. Scott

Keyword(s):

Feeding Behavior ◽

Fish Larvae ◽

Calanus Finmarchicus ◽

Gut Contents ◽

Selective Feeding ◽

Filter Feeding ◽

Sand Lance ◽

Food Items

Gut contents of northern sand lance (Ammodytes dubius) were identified, measured by volume, and compared to volumetric analyses of plankton hauls. A. dubius is a plankton feeder, copepods (mainly Calanus finmarchicus) constituting about 65% of its food by volume. It combines filter feeding with selective feeding on larger food items such as euphausiids and fish larvae.

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The box-balance model: a new tool to assess fish larval survival, applied to field data on two small pelagic fish

Marine Ecology Progress Series ◽

10.3354/meps13369 ◽

2020 ◽

Vol 650 ◽

pp. 289-308 ◽

Cited By ~ 2

Author(s):

V Raya ◽

J Salat ◽

A Sabatés

Keyword(s):

Field Data ◽

Fish Larvae ◽

Larval Growth ◽

Warming Trend ◽

Mortality Rates ◽

Larval Survival ◽

Pelagic Fish ◽

Balance Model ◽

Small Pelagic Fish ◽

Mesoscale Structures

This work develops a new method, the box-balance model (BBM), to assess the role of hydrodynamic structures in the survival of fish larvae. The BBM was applied in the northwest Mediterranean to field data, on 2 small pelagic fish species whose larvae coexist in summer: Engraulis encrasicolus, a dominant species, and Sardinella aurita, which is expanding northwards in relation to sea warming. The BBM allows one to quantify the contribution of circulation, with significant mesoscale activity, to the survival of fish larvae, clearly separating the effect of transport from biological factors. It is based on comparing the larval abundances at age found in local target areas, associated with the mesoscale structures (boxes), to those predicted by the overall mortality rate of the population in the region. The application of the BBM reveals that dispersion/retention by hydrodynamic structures favours the survival of E. encrasicolus larvae. In addition, since larval growth and mortality rates of the species are required parameters for application of the BBM, we present their estimates for S. aurita in the region for the first time. Although growth and mortality rates found for S. aurita are both higher than for E. encrasicolus, their combined effect confers a lower survival to S. aurita larvae. Thus, although the warming trend in the region would contribute to the expansion of the fast-growing species S. aurita, we can confirm that E. encrasicolus is well established, with a better adapted survival strategy.

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Feeding activity and diet composition of round goby (Neogobius melanostomus, Pallas 1814) in the coastal waters of SE Baltic Sea

Oceanological and Hydrobiological Studies ◽

10.1515/ohs-2015-0048 ◽

2015 ◽

Vol 44 (4) ◽

Cited By ~ 7

Author(s):

Artūras Skabeikis ◽

Jūratė Lesutienė

Keyword(s):

Baltic Sea ◽

Coastal Waters ◽

Diet Composition ◽

Feeding Activity ◽

Macoma Balthica ◽

Round Goby ◽

Benthic Fauna ◽

Neogobius Melanostomus ◽

The Body ◽

Gut Contents

AbstractFeeding activity and diet composition of round goby were investigated in the south-eastern Baltic Sea, the Lithuanian coastal waters during May-October 2012 in order to determine main feeding objects and seasonal periods when native fauna could be most affected by predation of this highly invasive species. In total, prey represented by 18 taxa was found in the gut contents of dissected fish. Feeding activity of round goby varied depending on the body size, sex and stage of the reproduction period. The gut contents of < 50 mm specimens were dominated by zooplanktonic and meiobenthic organisms, whereas larger individuals (50–99 mm) shifted to amphipods and mollusks. Individuals of the intermediate 100-200 mm length had a variable diet, changing depending on the season; in spring they mostly preyed on Macoma balthica, in summer − on polychaetes, while in autumn the contribution of Mytilus trossulus and fish considerably increased in their diet. Diet composition of individuals ≥ 200 mm was relatively constant in the course of the study with substantial preference to M. balthica. These findings imply that benthic fauna, particularly a newly settled generation of epibenthic mollusks in autumn is under strong predatory pressure of the round goby.

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Diet Composition and Seasonal Fluctuations in the Feeding Habit of Snow Barbel (Schizothorax plagiostomus) in River Indus, Pakistan

Acta Scientiae Veterinariae ◽

10.22456/1679-9216.82439 ◽

2018 ◽

Vol 46 (1) ◽

pp. 8

Author(s):

Muhammad Qayash Khan ◽

Muhammad Zubair Anjum ◽

Shamim Akhter ◽

Irfan Khattak ◽

Abid Ali

Keyword(s):

Diet Composition ◽

Feeding Activity ◽

Fish Fauna ◽

Feeding Habit ◽

Gut Contents ◽

Catch Per Unit Effort ◽

Food Items ◽

Unit Effort ◽

Significant Difference ◽

River Indus

Background:Schizothorax plagiostomus is widely distributed in river Indus and is most important food fish in Pakistan. The feeding habit of fish is directly related to the size of fish, its metabolic rate and environmental temperature. The accurate description of fish diet and feeding habit is a very important aspect in fisheries management for the purpose of species conservation, breeding and culture. The present work was aimed to investigate the specie abundance, the diet composition and seasonal variations in the feeding habit of Snow barbell Schizothorax plagiostomus.Materials, Methods & Results: A total of 1799 fish specimens were caught at the confluence of six tributaries along river Indus at Indus Kohistan, northeastern Pakistan. The fish were collected by 5-panels of gill net during first week of each month. The site specific Catch Per Unit Effort (CPUE) and season specific CPUE of fish fauna were assessed. For the gut content analysis 240 samples (99 male and 141 females) of S. plagiostomus were selected on monthly basis. Frequency of occurrence method and volumetric method were applied to record the different food items in the gut of S. plagiostomus. The physico-chemical parameters, NO3 concentration and dissolved Co2 of water from different localities of river Indus were recorded month wise by Hach sensION 156 meter, Horiba LAQUA Nitrate Meter and EA80 meter respectively. Significant difference was observed in water temperature during the four seasons. Except alkalinity no other water parameter showed significant variation across different localities. The results showed that highest Mean CPUE was observed for Darel Stream (0.55) and lowest for Jalkot stream (0.26). Peak abundance of fish was recorded in the month of November with a mean catch of 44.50, mean CPUE of 0.74 and mean Kruskal-Wallis rank value of 63.25. Spirogyra and Ulothrix occurred as maximum food items in the gut of S. plagiostomus during summer while their minimum amount occurred during autumn. According to the ranking index spirogyra and ulothrix ranked higher with significant difference in comparison to other food items. The results showed that S. plagiostomus is phytophagous in its feeding habit, which consumed mainly algae attached to stones and pebbles during the whole year. However, the presence of some secondary items such as animal matter, detritus, sand and mud might be due to the distinct availabilities of food along the seasons. The highest feeding activity of S. plagiostomus was recorded during summer while the lowest one occurred during autumn, spring and winter. Discussion: Catch per unit effort (CPUE) is an indirect measure of the abundance of a target species. It is used as an index of stock abundance in fisheries and conservation biology. During the study low fish fauna was found in River Indus as reported previously. Majority of the fish occurred in snow fed river tributaries in the study area as these tributaries are comparatively less turbulent. Previous studies have also recorded that Schizothoracine generally prefer clean waters. The present findings of gut contents analysis showed clearly that S. plagiostomus is a phytophagous fish which scrap and consumed spirogyra and ulothrix attached to stones and pebbles. Earlier it was reported that mouth of S. plagiostomusis is inferior, wide, with deep lower jaw having keratinized cutting edge and the lower lip is folded and expanded with numerous papillae making it best suited for scrapping algae attached to stones and pebbles. The highest feeding activity was observed during warmer months as compared to cold months. S. plagiostomus spawn twice in a year in autumn and in spring. The highest feeding activity of S. plagiostomus seems to be link with a reflex of recovery strategy due to physiological process of gonadal development.

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Temporal patterns in distributions of tropical fish larvae on the North West Shelf of Australia

Marine and Freshwater Research ◽

10.1071/mf03160 ◽

2004 ◽

Vol 55 (5) ◽

pp. 473 ◽

Cited By ~ 21

Author(s):

A. Sampey ◽

M. G. Meekan ◽

J. H. Carleton ◽

A. D. McKinnon ◽

M. I. McCormick

Keyword(s):

Southern Oscillation ◽

Fish Larvae ◽

Early Stage ◽

Larval Survival ◽

Zooplankton Biomass ◽

Tropical Fish ◽

North West ◽

Larval Fishes ◽

The North ◽

Abundance And Diversity

Information on the temporal distributions of tropical fish larvae is scarce. Early stage larval fishes were sampled using towed bongo plankton nets at sites on the southern North West Shelf of Australia (21°49′S, 114°14′E), between October and February of 1997/98 and 1998/99. The first summer was characterised by El Niño–Southern Oscillation-driven upwelling and high primary productivity, whereas in the second summer water temperatures were warmer and primary production was lower. Benthic percoid shorefishes dominated surface assemblages in both summers and this pattern may be typical of tropical shelf environments.The abundance and diversity of larval fishes were lowest in October and increased from November through to February. Assemblages displayed weak cross-shelf patterns, with a few taxa being more abundant at inshore sites (e.g. monacanthids), whereas others were more abundant offshore (e.g. scombrids). Although the composition of assemblages remained relatively consistent, many taxa (e.g. pomacentrids and carangids) showed differences in abundance between summers. Multivariate analyses found no relationships between abundance patterns of larval fishes and biophysical variables, such as temperature, salinity, and zooplankton biomass. Thus, seasonal changes in abundance may reflect differences in the spawning activities of adult fishes and/or larval survival.

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Ecomorphology and food habits of teleost fishes Trachinotus carolinus (Teleostei: Carangidae) and Menticirrhus littoralis (Teleostei: Sciaenidae), inhabiting the surf zone off Niterói, Rio de Janeiro, Brazil

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592010000800002 ◽

2010 ◽

Vol 58 (spe4) ◽

pp. 1-9 ◽

Cited By ~ 8

Author(s):

Luana Prestrelo Palmeira ◽

Cassiano Monteiro-Neto

Keyword(s):

Fish Species ◽

Food Habits ◽

Diet Composition ◽

Surf Zone ◽

Fish Larvae ◽

Sandy Beaches ◽

Size Class ◽

Class I ◽

Teleost Fishes ◽

Food Items

The ecomorphology and food habits of juvenile Trachinotus carolinus and Menticirrhus littoralis caught in the surf zone of sandy beaches in Niterói, RJ, were investigated between July 2006 and May 2007. These fish species differ morphologically, but present similarities in their diet composition suggest some slight overlapping in their diet. The importance of food items was assessed using Kawakami and Vazzoler's feeding index. Morphometric variables were recorded to correlate with the diet composition of the different size classes for each species. A total of 210 fishes (Trachinotus carolinus - 122, Menticirrhus littoralis - 88), ranging between 24.2 mm and 112 mm total length, were analyzed, but the stomachs of only 84.8% of them contained food. Trachinotus carolinus presented mysids, Polychaetes and Emerita spp. as the predominant items in their diet. Formicidae and Isopoda were the most important items for class I individuals, whereas mysids and Emerita spp. were important for classes II and III. Class I individuals also showed smaller sized prey (amphipods and isopods) and clupeid fish larvae in their diet. Emerita spp. dominated the food items of Menticirrhus littoralis regardless of the size class. Polychaetes, the second most important item was better represented in class sizes II and III. The main morphometric variable correlated with such differences included mouth position and diameter of the eye.

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Shifting boundaries of water, ice, flora, fauna, people, and institutions in the Arctic and Subarctic

ICES Journal of Marine Science ◽

10.1093/icesjms/fsy179 ◽

2018 ◽

Vol 75 (7) ◽

pp. 2293-2298

Author(s):

Kenneth F Drinkwater ◽

Franz J Mueter ◽

Sei-Ichi Saitoh

Keyword(s):

Fisheries Management ◽

Fish Larvae ◽

The United States ◽

Marine Conservation ◽

Calanus Finmarchicus ◽

The Arctic ◽

Arctic Seas ◽

Ecosystem Responses ◽

Water Ice ◽

Shifting Boundaries

Abstract An international Open Science Meeting entitled Moving in, out, and across the Subarctic and Arctic marine ecosystems: shifting boundaries of water, ice, flora, fauna, people, and institutions, took place 11–15 June 2017 in Tromsø, Norway. Organized by the Ecosystem Studies of Subarctic and Arctic Seas programme and cosponsored by the International Council for the Exploration of the Sea and the North Pacific Marine Science Organization, the primary aim of the meeting was to examine past, present, and future ecosystem responses to climate variability and ocean acidification (OA) and their effect on fishing communities, the fishing industry and fisheries management in the northern Pacific and Atlantic oceans and the Arctic. This symposium issue contains several papers from the meeting covering topics from climate and OA, ecosystem responses to environmental change, and fisheries management including: a synthesis of the ecosystem responses to the AMO-linked cold period of the 1970s and 1980s;a novel approach to understand responses to OA in northern climes using natural carbonate chemistry gradients, such as CO2 vents, methane cold seeps, and upwelling area;the possibility that warm temperatures are allowing two generations of Calanus finmarchicus per year to be produced;a new hypothesis suggesting that in areas where sea ice disappears there could be an increase of fish species with swim bladders;results from laboratory experiments on the effects of temperature and food on Arctic and boreal fish larvae;the application of ecosystem-based management in northern regions; anda description of the United States National Oceanic and Atmospheric Administration approach to marine conservation and how it affects fish populations and fisheries.

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Long-term stability in modelled zooplankton influx could uphold major fish spawning grounds on the Norwegian continental shelf

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2014-0524 ◽

2016 ◽

Vol 73 (2) ◽

pp. 189-196 ◽

Cited By ~ 8

Author(s):

Anders Frugård Opdal ◽

Frode B. Vikebø

Keyword(s):

Continental Shelf ◽

Gadus Morhua ◽

Fish Larvae ◽

Ocean Model ◽

Clupea Harengus ◽

Calanus Finmarchicus ◽

Crustacean Zooplankton ◽

Spawning Grounds ◽

Fish Spawning ◽

Norwegian Continental Shelf

Early life stages of fish spawned on the Norwegian continental shelf have long been suggested to depend on eggs and nauplii from the crustacean zooplankton Calanus finmarchicus for survival. Calanus finmarchicus overwinters in the deep basins of the Norwegian Sea, and gravid females must be advected onto the shelf prior to spawning if eggs and nauplii larvae are to serve as food for fish larvae. In this study, cross-shelf advection of C. finmarchicus is simulated over 52 years (1960–2011) using a numerical ocean model coupled with an individual-based model. The results suggest that cross-shelf transport of C. finmarchicus is surprisingly stable across years and that transport is particularly concentrated immediately upstream of the two major spawning areas for the Northeast Arctic cod (Gadus morhua) and the Norwegian spring-spawning herring (Clupea harengus), namely Lofoten and Møre, respectively. Two large topographical features, the Træna Trough and the Norwegian Trench, appear to be funnelling C. finmarchicus onto the shelf in these two areas. This could suggest that the fish spawning grounds outside Møre and Lofoten are, in part, maintained owing to stable interannual food supply in spring.

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Crustacea in the Diet of Eledone Cirrhosa (Mollusca: Cephalopoda) determined by Serological Methods

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400048499 ◽

1986 ◽

Vol 66 (4) ◽

pp. 867-879 ◽

Cited By ~ 28

Author(s):

P. R. Boyle ◽

M. S. Grisley ◽

G. Robertson

Keyword(s):

Positive Reaction ◽

Visual Recognition ◽

Prey Species ◽

Carcinus Maenas ◽

Peak Height ◽

Gut Contents ◽

Field Sample ◽

Cancer Pagurus ◽

Prey Identification ◽

Moray Firth

Serological methods for prey identification have been applied to the gut contents of a field sample of 100 Eledone cirrhosa from the Moray Firth and 7 from the Sound of Jura. Protein extracts from the crop were electrophoresed (Laurell rockets) into antisera raised against potential crustacean prey species, Cancer pagurus, Carcinus maenas, Crangon crangon, Liocarcinus spp. and Nephrops norvegicus. The strengths of the resulting reactions were evaluated on the basis of peak height, staining density and the number of homocentric peaks of immune precipitates. Sixty-two of the 100 Moray Firth animals gave a positive reaction to one or more of the antisera and the most critical assessment of the results ranked the incidence of the prey as Liocarcinus (15) > Nephrops (10) > Cancer (8) > Crangon (2) > Carcinus (0), a total of 35 reactions from 28 animals. Absence of a reaction in the 38 animals from which appreciable sample volumes were also obtained indicates that alternative prey had been consumed. Of the 7 Sound of Jura animals, 4 gave a positive reaction to Nephrops alone. A total of only 24 animals gave any indication of diet by visual recognition of remains. The value and difficulties of the methodology are discussed.

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