Temporal and Age‐Based Variation in Juvenile Sablefish Diet Composition and Quality: Inferences from Stomach Contents and Stable Isotopes

We examined the stomach contents of two of the most economically and ecologically important small pelagic fish species, the sardine, Sardina pilchardus and the anchovy, Engraulis encrasicolus, obtained monthly from commercial purse-seine catches operating on Croatian fishing grounds during a one-year period (January–December, 2011). Both species generally showed a similar diet, with copepod and decapod larvae as dominant prey groups. The composition of anchovy and sardine stomach contents was not size- or sex-related, but throughout the year, a significant difference in diet composition was observed for each species as well as between species. Two gastrointerstinal helminths; the digenean Parahemiurus merus and nematode Hysterothylacium aduncum, were recorded during the stomach content analysis. Differences in population dynamics between the two parasites are congruent with differences in the prey composition of sardine and anchovy, reflecting fine-tuned interactions in the trophic web between parasites and intermediate or paratenic hosts included in the sardine and anchovy diet.

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Population dynamics and feeding ecology of the invasive Caucasian dwarf goby, Knipowitschia caucasica, in a freshwater habitat in Ukraine

Knowledge and Management of Aquatic Ecosystems ◽

10.1051/kmae/2020018 ◽

2020 ◽

pp. 26

Author(s):

Alexander Didenko ◽

Igor Buzevych ◽

Yuriy Volikov ◽

Svitlana Kruzhylina ◽

Alexander Gurbyk

Keyword(s):

Population Dynamics ◽

Littoral Zone ◽

Diet Composition ◽

Sampling Site ◽

Age Groups ◽

Stomach Contents ◽

Seasonal Fluctuations ◽

Chironomid Larvae ◽

High Diversity ◽

Two Age Groups

Population dynamics and feeding patterns of invasive Knipowitschia caucasica were studied in the littoral zone of the lower Stugna River. The abundances of this goby showed significant inter-annual and seasonal fluctuations. The studied population of K. caucasica was represented by two age groups (0 and I). Fish die after their first breeding season. In total, 58 prey items were identified in the diet of K. caucasica at the sampling site. The most abundant prey were copepods and cladocerans, while the most frequently encountered prey were copepods and chironomid larvae. Copepods were represented mainly by Cyclopoidae. Cladocerans included 21 taxa, among which the most abundant were Diaphanosoma sp., Acroperus harpae, and Disparalona rostrata; chironomids included 22 taxa, among which the most abundant was Cricotopus sylvestris. The diet composition showed seasonal dynamics, where copepods predominated in January to April and in August-September, chironomid larvae were especially important in May to July, while cladocerans were most important in November-December. The relatively high diversity of both phytophilous and open-bottom-dwelling prey organisms in the stomach contents of K. caucasica indicates that this species fed on a large variety of benthic habitats including among macrophytes and open areas.

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DESCRIBING A SPECIES-RICH RIVER FOOD WEB USING STABLE ISOTOPES, STOMACH CONTENTS, AND FUNCTIONAL EXPERIMENTS

Dynamic Food Webs ◽

10.1016/b978-012088458-2/50037-0 ◽

2005 ◽

pp. 395-406 ◽

Cited By ~ 11

Author(s):

Craig A. Layman ◽

Kirk O. Winemiller ◽

D. Albrey Arrington

Keyword(s):

Stable Isotopes ◽

Food Web ◽

Stomach Contents

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Stable isotopes in jumbo squid (Dosidicus gigas) beaks to estimate its trophic position: comparison between stomach contents and stable isotopes

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315406013324 ◽

2006 ◽

Vol 86 (2) ◽

pp. 437-445 ◽

Cited By ~ 53

Author(s):

R.I. Ruiz-Cooley ◽

Unai Markaida ◽

D. Gendron ◽

S. Aguíñiga

Keyword(s):

Stable Isotopes ◽

Stable Isotope ◽

Trophic Position ◽

Stomach Contents ◽

Isotope Ratios ◽

Trophic Relationships ◽

Dosidicus Gigas ◽

Jumbo Squid ◽

C And N ◽

Biomass Increase

Stomach contents and carbon (C) and nitrogen (N) stable isotope analysis were used to evaluate trophic relationships of jumbo squid, Dosidicus gigas. Buccal masses, beaks and stomach contents of large and medium maturing-sized jumbo squid and muscle from its main prey, the myctophid Benthosema panamense, were collected in the Gulf of California, Mexico during 1996, 1997 and 1999. Both the quantified C and N-isotope ratios in muscle, and stomach content analysis revealed that larger-sized maturing squid showed a higher trophic position than medium-sized individuals. However, a discrepancy between stomach contents versus stable isotope analyses was found in evaluating trophic relationships. Simple dilution models as a function of growth were used to estimate the C and N renewal dietary shift for jumbo squid. Estimates of the initial C and N pools in D. gigas with an initial age of 70 days and 210 days indicated isotopic shifts of 32% after a threefold biomass increase and 25% after a fourfold biomass increase, respectively. Additionally, beak samples of jumbo squid were evaluated as an alternative tissue to estimate squid trophic position using stable isotopes. The results showed a significant correlation between stable isotope ratios from muscle and beak samples. Muscle isotope values were higher than beak by 1% and 4% for δ13C and δ15N respectively. A test with jumbo squid beaks collected from a stomach of a stranded sperm whale confirmed the viability of this method.

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Diversity of ants and mites in the diet of the Brazilian frog Chiasmocleis leucosticta (Anura: Microhylidae)

Biota Neotropica ◽

10.1590/1676-0611-bn-2017-0323 ◽

2017 ◽

Vol 17 (3) ◽

Author(s):

Mariana S. Lopes ◽

Ricardo S. Bovendorp ◽

Gilberto José de Moraes ◽

Alexandre Reis Percequillo ◽

Jaime Bertoluci

Keyword(s):

Diet Composition ◽

Statistical Difference ◽

Stomach Contents ◽

Southeastern Brazil ◽

Pitfall Traps ◽

Prey Category ◽

Food Items ◽

The Family ◽

Family Level ◽

Males And Females

Abstract We describe here the diet of the microhylid frog Chiasmocleis leucosticta based on the stomach contents of 72 individuals (47 males and 25 females) collected in pitfall traps at the Reserva Florestal de Morro Grande, state of São Paulo, southeastern Brazil. We identified 1,981 food items distributed in 13 prey categories of arthropods, mainly ants, mites and collembolans. Formicidae was the most abundant and frequent prey category, including 16 genera from seven subfamilies, and data on ant availability in the habitat suggest that C. leucosticta selects ants actively. The second main prey category was Acari, predominantly represented by mites of the suborder Oribatida. This is the first work identifying mites to the family level in the diet of a Microhylidae. There was no statistical difference between males and females regarding diet composition.

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Assessing the dietary sources of two cichlid species in River Nile sub-branches: Stomach contents, fatty acids and stable isotopes analyses

The Egyptian Journal of Aquatic Research ◽

10.1016/j.ejar.2016.05.001 ◽

2016 ◽

Vol 42 (2) ◽

pp. 205-213 ◽

Cited By ~ 3

Author(s):

Mohamad S. Abd El-Karim ◽

Mohamad H.H. Ali ◽

Abeer M.A. Mahmoud

Keyword(s):

Fatty Acids ◽

Stable Isotopes ◽

Stomach Contents ◽

River Nile ◽

Cichlid Species

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Desert pumpkinseed: diet composition and breadth in a Moroccan river

Knowledge and Management of Aquatic Ecosystems ◽

10.1051/kmae/2021033 ◽

2021 ◽

pp. 34

Author(s):

Christos Gkenas ◽

Maria Filomena Magalhães ◽

Nazaret Campos-Martin ◽

Filipe Ribeiro ◽

Miguel Clavero

Keyword(s):

Arid Regions ◽

Diet Composition ◽

Prey Availability ◽

Stomach Contents ◽

Elevational Gradient ◽

Diet Breadth ◽

Lepomis Gibbosus ◽

Feeding Plasticity ◽

Generalist Diet ◽

Widely Invasive

The widely invasive North American pumpkinseed sunfish, Lepomis gibbosus, is currently established in desert rivers in Morocco. The success of pumpkinseed in novel ecosystems has been associated with its generalist diet, but this trait remains unevaluated in arid regions. Desert rivers are harsh environments with limited water and prey availability which may adversely constrain the diet of fish. Here we studied the diet of pumpkinseed across 4 sites in the Draa River, embracing a 450 m elevational gradient covering from extremely dry lowlands to relatively humid highlands. We described pumpkinseed diet through the analysis of stomach contents of 82 individuals, collected in the fall of 2013. Pumpkinseed diet was dominated by Chironomidae in dry lowlands, while Ephemeroptera, Heteroptera, Trichoptera and Odonata were relevant prey in more humid highlands. Population diet breadth expanded with elevation, but individual specialization in diet was low among all sites. Our results highlight considerable changes in diet composition and breadth with aridity, suggesting that feeding plasticity and use of exclusive, locally abundant prey rather than generalized feeding may be associated with the success of pumpkinseed in most arid areas in desert rivers.

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Feeding of tub gurnard Chelidonichthys lucerna (Scorpaeniformes: Triglidae) in the north-east Mediterranean

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315411000671 ◽

2011 ◽

Vol 92 (3) ◽

pp. 605-612 ◽

Cited By ~ 11

Author(s):

Marco Stagioni ◽

Stefano Montanini ◽

Maria Vallisneri

Keyword(s):

Diet Composition ◽

Foraging Behaviour ◽

Adriatic Sea ◽

Feeding Habits ◽

Feeding Activity ◽

Stomach Contents ◽

East Mediterranean ◽

North East ◽

The North ◽

Important Prey

The stomach contents of 1096 specimens of Chelidonichthys lucerna were examined in order to analyse their diet composition according to fish size, sex, depth and season. Sampling was carried out from May 2005 to March 2007 during several bottom trawl surveys in the Adriatic Sea (north-east Mediterranean). Feeding activity was more intense in juveniles than in adults. The most important prey was Crustacea (mainly Decapoda: Brachyura, such as Goneplax rhomboides, Liocarcinus spp., Philocheras spp.) and Teleostei (mainly European anchovy Engraulis encrasicolus and black goby Gobius niger). There was no difference between male and female diet. Feeding habits varied with size, with fish dominating the stomach contents of larger specimens. Finally, fish increased in winter and crustaceans in summer. Chelidonichthys lucerna shows a generalist and opportunistic foraging behaviour, preying mainly epibenthic and nectobenthic organisms.

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