Feeding ecology of invasive Perccottus glenii (Perciformes, Odontobutidae) in Slovakia

Stomach contents of 331 specimens of Perccottus glenii (Perciformes: Odontobutidae) were analysed. Chironomids and ephemeropterans dominated the diet of all size classes of fish; however, the frequency of crustaceans was also high. Micro-crustaceans (ostracods, copepods and cladocerans) dominated in lower size classes (20–39 mm); macro-crustaceans (Isopoda, Amphipoda) dominated in higher size classes (up to 79 mm). The proportion of crustaceans decreased from the size class 80–89 mm. With the increasing size of fish the frequency of molluscs (Gastropoda) increased, the maximum was in size class 70–79 mm. Cannibalism occurred from 60 mm, and it was significant from 80 mm. The highly mobile invertebrates (Coleoptera, Heteroptera) were found in the largest size classes. In middle size classes (40–59 mm), the widest spectrum of prey units was documented; the food variability of small (90 mm) individuals was poor. Differences in the diet composition of small individuals were negligible; the diet of the largest ones differed significantly. According to diet, two feeding size class groups were recognised: the first

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Diet of the endangered spirlin (Alburnoides bipunctatus) at the centre of its distribution in Europe

Marine and Freshwater Research ◽

10.1071/mf18013 ◽

2018 ◽

Vol 69 (11) ◽

pp. 1712

Author(s):

L. Marszał ◽

M. Grzybkowska ◽

D. Błońska ◽

J. Leszczyńska ◽

M. Przybylski

Keyword(s):

Resource Use ◽

Diet Composition ◽

Feeding Habits ◽

Open Water ◽

Size Class ◽

Habitat Segregation ◽

Chironomid Larvae ◽

Size Classes ◽

Taxonomic Groups ◽

Distribution In Europe

The feeding habits of spirlin Alburnoides bipunctatus were investigated in a tributary of the River Vistula (Poland). To evaluate size-related patterns of resource use, fish were assigned to three size classes, defined according to size at first maturation: small (29–70-mm total length, TL), medium (71–90mm TL) and large (91–104mm TL). There was a significant ontogenetic shift in the feeding pattern among size classes, marked by differences in the proportion of the main taxonomic groups of prey consumed: small spirlin primarily consumed chironomid larvae, whereas medium and large spirlin showed a preference for Coleoptera, Ephemeroptera and imagines of unidentified insects. The proportion of prey taken from the water column was significantly lower for small- than medium- and large-sized spirlin. This difference was attributed to the benthic habits of small spirlin compared with medium and large spirlin. The shift to open water feeding in spirlin corresponded with sexual maturation, with habitat segregation between the smallest size class (comprising juveniles) and larger size classes (mature individuals). Size-specific changes in the diet composition of this species have not previously been documented.

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Diet, feeding behaviour and habitat utilisation of the blue stingray Dasyatis chrysonota (Smith, 1828) in South African waters

Marine and Freshwater Research ◽

10.1071/mf03069 ◽

2003 ◽

Vol 54 (8) ◽

pp. 957 ◽

Cited By ~ 37

Author(s):

David A. Ebert ◽

Paul D. Cowley

Keyword(s):

Surf Zone ◽

Stomach Contents ◽

Size Class ◽

Behaviour Pattern ◽

Medium Size ◽

Secondary Importance ◽

Size Classes ◽

Important Prey ◽

Large Size ◽

Large Size Class

Analysis of stomach contents for Dasyatis chrysonota revealed that diet varied with size and habitat. The diet of all size classes in the surf zone was comprised primarily of Callianassa spp., Donax spp. and unidentified polychaete species. The medium and large size classes fed primarily on Donax spp., whereas the very large size class fed mainly on Callianassa spp. Polychaetes were of secondary importance as prey for the medium size class. The diet of D. chrysonota in the nearshore zone consisted mainly of Balanoglossus capensis and Callianassa spp. Balanoglossus capensis decreased from an index of relative importance (IRI) of 75.3% for the medium size class to 59.9% for the very large size class, whereas Callianassa spp. increased from 22.8% to 39.4% between the medium and the very large size classes. The offshore zone was the only area in which small size class D. chrysonota were caught. The diet of these small D. chrysonota was primarily polychaetes and amphipods. Polychaetes increased in importance in the medium size class, but declined in each successively larger size class. Conversely, Pterygosquilla armata capensis became the single most important prey item for the very large size class, comprising an IRI of 50.9%. The behaviour pattern used by D. chrysonota to locate and extract prey is described.

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Feeding ecology of the piked spurdog Squalus megalops (Chondrichthyes: Squalidae) in the Gulf of Gabès (central Mediterranean Sea)

Marine and Freshwater Research ◽

10.1071/mf17018 ◽

2018 ◽

Vol 69 (1) ◽

pp. 48

Author(s):

Sondes Marouani ◽

Hasna Kadri ◽

Sami Karaa ◽

Mohamed Nejmeddine Bradai

Keyword(s):

Feeding Ecology ◽

Trophic Position ◽

Stomach Contents ◽

Size Class ◽

Relative Importance ◽

Central Mediterranean ◽

Gulf Of Gabes ◽

Gulf Of Gabès ◽

Index Of Relative Importance ◽

Three Factor

The present study investigated the feeding ecology of the piked spurdog (Squalus megalops) in the Gulf of Gabès (Tunisia) with regard to sex, size class and season. A study of stomach contents from the 630 individuals examined showed that the species consumed teleosts (percentage index of relative importance (%IRI)=80.32), cephalopods (%IRI=11.96) and crustaceans (%IRI=7.68). A three-factor multivariate analysis of variance (MANOVA) demonstrated significant differences in diet related to size, season and sex. Trophic position analysis revealed that S. megalops is a secondary consumer throughout its life. Quantitative analysis indicated that the species is a generalist feeder with an ontogenetic change in preferred prey from crustaceans to teleosts. The niche breadths of S. megalops in both sexes were broad.

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Feeding ecology of monkfish Lophius gastrophysus in the south-western Atlantic Ocean

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315408000301 ◽

2008 ◽

Vol 88 (1) ◽

pp. 205-212 ◽

Cited By ~ 5

Author(s):

M.F.M. Valentim ◽

E.P. Caramaschi ◽

M. Vianna

Keyword(s):

Atlantic Ocean ◽

Feeding Ecology ◽

Seasonal Pattern ◽

Stomach Contents ◽

Size Class ◽

The South ◽

Feeding Intensity ◽

Western Atlantic ◽

Index Value ◽

Janeiro State

The diet of the monkfish Lophius gastrophysus is described based on the analysis of stomach contents, for the south-western Atlantic from samples landed in the fishing port of Niteroi, Rio de Janeiro state, Brazil, from April 2004 to March 2006. Feeding intensity, measured as the presence or absence of contents in stomachs, and differences in the items' composition were analysed by sex, size-class and season. High feeding intensity predominated for females >32 cm and for males <31 cm. There was no seasonal pattern in the occurrence of full or empty stomachs. The most important category in the diet was fish with 25 identified species. Dactylopterus volitans showed the highest alimentary index value, mainly because of the feeding of juvenile monkfish. The second most important category was Mollusca, represented mainly by squid. No relationships between predator- and prey-lengths and weights were observed; but there was a tendency to consume light and small prey independently of the size of the monkfish.

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Feeding ecology of electric eel Electrophorus varii (Gymnotiformes: Gymnotidae) in the Curiaú River Basin, Eastern Amazon

Neotropical Ichthyology ◽

10.1590/1982-0224-2019-0132 ◽

2020 ◽

Vol 18 (3) ◽

Author(s):

Raimundo Nonato Gomes Mendes-Júnior ◽

Júlio César Sá-Oliveira ◽

Huann Carllo Gentil Vasconcelos ◽

Carlos Eduardo Costa-Campos ◽

Andrea Soares Araújo

Keyword(s):

River Basin ◽

Diet Composition ◽

Feeding Activity ◽

Stomach Contents ◽

Size Class ◽

Stomach Fullness ◽

Fish Predators ◽

Electric Eel ◽

Feeding Parameters ◽

Stomach Weight

ABSTRACT In this study, the composition of the diet and the feeding activity of Electrophorus varii were evaluated. The influence of ontogeny and seasonality in these feeding parameters was also examined. Fish were collected in the Curiaú River Basin, Amazon, Brazil, from March 2005 to February 2006, during the rainy (January-June) and dry (July-December) seasons. Diet composition was characterized based on the analysis of stomach contents and feeding dynamics was assessed based on the Stomach Fullness Index (IR) calculated using stomach weight. Stomach content and RI data were grouped into four-cm size classes (40-80, 80-120, 120-160, and 160-200) and two seasonal periods (rainy and dry). The influence of ontogeny and seasonality in the diet was investigated through PERMANOVA, and in the food dynamics through ANOVA. The analysis of stomach contents revealed that fish were the most consumed preys by electric eels, especially Callichthyidae and Cichlidae. Diet composition and RI values of electric eels were not influenced by ontogeny and seasonality. Electric eels are fish predators, regardless of size class and seasonal period.

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Feeding ecology of Erythrolamprus jaegeri jaegeri (Günter, 1858) and Erythrolamprus poecilogyrus sublineatus (Cope, 1860) in the coastal zone of Subtropical Brazil (Serpentes, Dipsadidae)

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201520140570 ◽

2016 ◽

Vol 88 (1) ◽

pp. 293-308 ◽

Cited By ~ 2

Author(s):

DANIELE N. CORRÊA ◽

FERNANDO M. QUINTELA ◽

DANIEL LOEBMANN

Keyword(s):

Feeding Ecology ◽

Diet Composition ◽

Niche Breadth ◽

Prey Selection ◽

Coastal Region ◽

Stomach Contents ◽

Niche Overlap ◽

Southern Brazil ◽

Lower Jaw ◽

Positive Correlations

ABSTRACT The snakes Erythrolamprus jaegeri jaegeri and Erythrolamprus poecilogyrus sublineatus are sympatric and syntopic in the coastal region of southern Brazil. Herein, we analyzed the diet composition to evaluate the niche breadth and the prey selection by both species. We examined 192 specimens, and analysis of stomach contents revealed that both species predominantly consume anurans. However, the diet of E. j. jaegeri consists mainly of fish and amphibians, whereas that of E. p. sublineatus is broader, including fish, amphibians, reptiles and mammals. The Standardized Levins Index presented lower values for E. j. jaegeri (BA = 0.17) than for E. p. sublineatus (BA = 0.61), evidencing specialist and generalist strategies for each species, respectively. Regarding prey selection, E. p. sublineatus presented a larger snout-vent length, head, mouth and lower jaw than E. j. jaegeri and fed on larger prey. In addition, positive correlations between the size and weight of predators and prey were confirmed in both species. The results show the development of different mechanisms for co-occurrence of the two species, such as prey selection by size, such that the size of the predator is related to the size of their prey, or by developing different strategies to decrease niche overlap between species.

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Feeding ecology of black anglerfish Lophius budegassa: seasonal, bathymetric and ontogenetic shifts

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315406013816 ◽

2006 ◽

Vol 86 (4) ◽

pp. 877-884 ◽

Cited By ~ 29

Author(s):

Izaskun Preciado ◽

Francisco Velasco ◽

Ignacio Olaso ◽

Jorge Landa

Keyword(s):

North Atlantic ◽

Feeding Ecology ◽

Diet Composition ◽

Atlantic Coast ◽

Stomach Contents ◽

Large Prey ◽

Age Classes ◽

Feeding Intensity ◽

Merluccius Merluccius ◽

Important Prey

The diet of black anglerfish Lophius budegassa is described for the Cantabrian Sea (North Atlantic coast of Spain) from seasonal samples obtained onboard commercial vessels from January 1993 to December 1994. The stomach contents of fish caught on the continental shelf were examined, and differences in the diet in relation to age-class, season and depth were studied. The age-classes were grouped according to a cluster analysis of diet composition. As a result, three groups were obtained: the first two corresponded to juveniles between 2 and 7 years old, and the third one corresponded to adults between 8 and 15 years old. Although Micromesistius poutassou was an important prey for all ages, the youngest black anglerfish fed mainly on small benthic fish. In contrast, large prey species such as Phycis blennoides and Merluccius merluccius were eaten almost exclusively by adults. The diet composition changed during the year. The changes in the diet of black anglerfish older than 3 years were more related to seasonal differences than to between-size differences. These seasonal shifts were mainly marked by the varying importance of Trachurus trachurus and M. merluccius in their diet. Feeding intensity also showed seasonal variations, with a significant decrease in autumn. An indirect effect of depth on the feeding ecology of black anglerfish was also found, since both age and diet composition changed with depth.

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Diet overlap and feeding preference of Oreochromis niloticus (Linnaeus, 1758) versus two native cichlids of the upper Kabompo River, northwest of Zambia.

10.22541/au.163898045.52297636/v1 ◽

2021 ◽

Author(s):

Arthertone Jere

Keyword(s):

Oreochromis Niloticus ◽

Native Species ◽

Feeding Habits ◽

Stomach Contents ◽

Niche Overlap ◽

Size Class ◽

Diet Shift ◽

Food Web Structure ◽

Size Classes ◽

Dietary Niche

Evaluating the food and feeding habits of fish is fundamental in fisheries and conservation biology research. In this study, the diet of exotic Oreochromis niloticus was compared with the 2 most abundant and aquaculture preferred native cichlids of native species (Orochromis macrochir and Coptodon rendalli) in the upper Kabompo River, Zambia. We hypothesized that exotic and native cichlids would show no dietary niche overlap. We analyzed the stomach contents of 114 specimens of the fishes sampled. Fishes were grouped into 3 major feeding groups: microphages, macrophages and carnivores, and omnivores. They were also grouped into size classes of <50, 51−100, 101−150, and 151−302 mm total length (TL). O. niloticus had a larger dietary niche than two native species (71% and 22%, respectively). The dietary niche overlap between O. niloticus and native C. rendalli species in size classes <50 was significant (F (2, 45) = 0.084, p < 0.05). Dietary niche overlap between the native O. macrochir species in size class <50 mm was low (F (2, 33) = 2.13, p > 0.05), while as in size classes 51−100 mm and 101−150 mm was high (F (2, 35) = 0.27, p < 0.05) for C. rendalli. There was no clear evidence of ontogenetic diet shift of native cichlids, with the exception of O. macrochir, which showed ontogenetic diet shifts within the 51−100 mm size class. The dietary overlap results indicate interspecific competition between exotic O. niloticus and native O. macrochir, which may have major impacts on food web structure in the upper Kabompo River and may explain population decreases of some native species.

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