Same Diet, Different Strategies: Variability of Individual Feeding Habits across Three Populations of Ambrosi’s Cave Salamander (Hydromantes ambrosii)

European cave salamanders of the genus Hydromantes are a group of eight species endemic to Italy and south-eastern France. Knowledge on the trophic niche of European Hydromantes is poor, and the few available studies only partially investigate their feeding habits. We performed an in-depth study on the trophic niche of the Ambrosi’s cave salamander (H. ambrosii), assessing the potential divergences among three different populations. All the populations had a similar diet composition, showing a wider trophic niche in fall compared to spring. In only one population, “true specialists” were present; however, in all three populations, generalist individuals always represented the larger proportion. Interspecific and intraspecific competition did not play an important role in determining individual dietary specialisation in H. ambrosii; contrarily, the characteristics of the surrounding environment seemed to be an important factor. The best body conditions were observed in the population located in the site where the non-arboreal vegetation cover was the highest. Besides providing new information on the trophic niche of H. ambrosii, we here showed that studies encompassing both intrinsic and extrinsic factors at the population level are needed to fully understand the trophic dynamics occurring among European cave salamanders.

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Trophic generalism at the population level in ground beetles (Coleoptera: Carabidae)

The Canadian Entomologist ◽

10.4039/tce.2015.61 ◽

2015 ◽

Vol 148 (3) ◽

pp. 284-293 ◽

Cited By ~ 4

Author(s):

Marcin Zalewski ◽

Dorota Dudek-Godeau ◽

Jean-François Godeau ◽

Krzysztof Kujawa ◽

Paweł Sienkiewicz ◽

...

Keyword(s):

Trophic Level ◽

Population Level ◽

Habitat Diversity ◽

Ground Beetles ◽

Trophic Niche ◽

Isotopic Ratios ◽

Local Resources ◽

Northeastern Poland ◽

Different Populations ◽

Local Habitat

AbstractA growing body of evidence suggests trophic generalism (feeding on resources from more than one trophic level and/or on different resources of the same trophic level) is a widespread feature among ground beetles (Coleoptera: Carabidae). However, it remains unclear whether trophic generalism applies to single individuals, at the intrapopulation or interpopulation level. Here we present stable isotope data (δ15N, δ13C) of seven common European carabid species on an archipelago of 18 lake islands in northeastern Poland. We found strong differences in isotopic ratios between individuals of the same population as well as between different populations, indicating that carabids are opportunistic feeders and that the degree of opportunism differs between habitats and between islands. Trophic niche breadth as assessed by isotopic ratios was influenced by local habitat diversity. We suggest that opportunistic usage of different local resources results in striking differences between local populations and a very broad trophic niche observed at regional level.

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Feeding habits of the toothed flounder Cyclopsetta querna (Paralichthyidae) of the south-east Gulf of California

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315410000603 ◽

2010 ◽

Vol 91 (6) ◽

pp. 1225-1230 ◽

Cited By ~ 2

Author(s):

Felipe Amezcua ◽

Alfonso Portillo ◽

Felipe Amezcua-Linares

Keyword(s):

Gulf Of California ◽

Diet Composition ◽

Niche Breadth ◽

Feeding Habits ◽

Demersal Fish ◽

Trophic Niche ◽

The South ◽

Top Predators

Feeding habits of the toothed flounder Cyclopsetta querna caught in the south-east Gulf of California were studied. Specimens were collected via demersal fish surveys. Results of this study show that C. querna is a predator that focuses on fish inhabiting the bottom and in particular on tonguefish (Symphurus sp.), midshipman fish (Porichthys sp.) and moray eels (Muraenidae). The diet of the toothed flounder did not vary significantly throughout the period of study, and neither size nor sex-related variations in diet composition were observed. Simpson's index indicates a limited trophic niche breadth with a diet dominated by a limited number of taxa. The estimated TROPH value for C. querna is similar to that estimated for other demersal top predators from the studied area; therefore, the toothed flounder can be considered a top carnivore from the demersal community in the Gulf of California.

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Diet composition and feeding habits of the pelagic thresher shark Alopias pelagicus in Eastern Central Pacific Ocean, Ecuadorian waters

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315420000569 ◽

2020 ◽

Vol 100 (5) ◽

pp. 837-845

Author(s):

Marcos D. Calle-Morán ◽

Felipe Galván-Magaña

Keyword(s):

Diet Composition ◽

Feeding Habits ◽

Trophic Niche ◽

Maturity Stage ◽

Dosidicus Gigas ◽

Central Pacific ◽

Central Pacific Ocean ◽

Jumbo Squid ◽

Top Predators ◽

Thresher Shark

AbstractThe diet and feeding habits of the pelagic thresher shark Alopias pelagicus were analysed based on 104 stomachs (N = 84 females, 20 males) collected off Santa Rosa de Salinas, in the Ecuadorian Pacific. The sharks were caught between February 2008 and January 2009 in artisanal fisheries. The trophic spectrum of A. pelagicus included 19 prey items (10 cephalopods and 9 teleost fishes), the main four prey were the red flying squid Ommastrephes bartramii, jumbo squid Dosidicus gigas, the purpleback flying squid Sthenoteuthis oualaniensis and the South Pacific hake Merluccius gayi. The trophic niche was narrow (Bi = 0.2), thus the pelagic thresher could be considered a specialist predator. The analysis of dietary overlap showed high similarity between the diets of females and males (Cλ = 0.99), immature and mature females (Cλ = 0.81), immature and mature males (Cλ = 0.72), sizes of 141–230 cm TL and 231–321 cm TL (Cλ = 0.97), as well as sharks in rainy season and dry season (Cλ = 0.77). Using canonical of correspondence analysis (CCA), we found similarities in the diet for all categories recorded (sex: canonical r = 0.38, P = 0.97; sexual maturity stage: canonical r = 0.54, P = 0.31; sizes: canonical r = 0.55, P = 0.26; seasons of the year: canonical r = 0.61, P = 0.75). The trophic level estimated for A. pelagicus was 5.0, which is typical of top predators (quaternary consumers or tertiary carnivores).

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Morphological peculiarities of seeds of some species of the genus Epipactis Zinn. (Orchidaceae Juss.) of Ukrainian flora

Biolohichni systemy ◽

10.31861/biosystems2019.01.093 ◽

2019 ◽

Vol 11 (1) ◽

pp. 93-100

Author(s):

T Ljubka ◽

O Tsarenko ◽

I Tymchenko

Keyword(s):

Seed Coat ◽

Cell Walls ◽

Morphological Study ◽

Population Level ◽

Intercellular Spaces ◽

Different Populations ◽

Periclinal Walls ◽

High Degree ◽

Shape And Size ◽

Generative Organs

The investigation of macro- and micromorphological peculiarities of seeds of four species of genus Epipactis (Orchidaceae) of Ukrainian flora were carried out. The genus Epipactis is difficult in the in in taxonomic terms and for its representatives are characterized by polymorphism of morphological features of vegetative and generative organs of plants and ability of species to hybridize. The aim of the research was to perform a comparative morphological study of seeds of E. helleborine, E. albensis, E. palustris, E. purpurata and to determine carpological features that could more accurately identify species at the stage of fruiting. A high degree of variation in the shape of the seeds in different populations within the species and overlap of most quantitative carpological characteristics of studied species are noted. There were no significant differences in micromorphological features of the structure of the testa at species or population level. The reticulate surface of the testa is characteristic of all species, the cells of testa are mostly elongated, penta-hexagonal, individual cells almost isodiametric-pentagonal. From the micropillary to the chalasal end, a noticeable change in the shape and size of the seed coat cells is not observed. There are no intercellular spaces, the anticlinal walls of adjacent cells are intergrown and the boundaries between them become invisible. The outer periclinal walls have a single, mainly longitudinal thin ribbed thickenings. Anticlinal cell walls are thick, dense, smooth. The longitudinal Anticlinal walls are almost straight, transverse - straight or sometimes curved in some cells. Epicuticular deposits on the periclinal walls are absent. It is concluded that the use of macro and micromorphological characteristics of seeds of these species for clearer diagnosis at the stage of fruiting is low informative.

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Feeding ecology of Symbolophorus californiensis larvae (Teleostei: Myctophidae) in the southern transition region of the western North Pacific

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315409990464 ◽

2009 ◽

Vol 90 (6) ◽

pp. 1249-1256 ◽

Cited By ~ 12

Author(s):

Chiyuki Sassa

Keyword(s):

Transition Region ◽

North Pacific ◽

Western North Pacific ◽

Developmental Stages ◽

Feeding Habits ◽

Larval Growth ◽

Trophic Niche ◽

Size Class ◽

Gut Contents ◽

Wide Range

The feeding habits of myctophid larvae of Symbolophorus californiensis were examined in the southern transition region of the western North Pacific where the main spawning and nursery grounds of S. californiensis are formed. This species is a key component of the pelagic ecosystems of this region, and their larvae attain one of the largest sizes among myctophids. To analyse gut contents larvae, including most life history stages after yolk-sac absorption (3.7 to 22.2 mm body length (BL)), were collected in the upper 100 m layer in 1997 and 1998. Feeding incidence was higher during the day than at night (53.1–92.3% versus 0–5.6%), and daytime feeding incidence increased gradually with larval growth. Larvae fed mainly on copepods of various developmental stages. Larvae of S. californiensis showed an ontogenetic change in their diet: larvae ≤7.9 mm BL (i.e. preflexion stage) fed mainly on copepod eggs and nauplii, while the larvae ≥8 mm BL consumed mainly calanoid copepodites such as Pseudocalanus and Paracalanus spp. In the largest size-class (16–22.2 mm BL), the furcilia stage of euphausiids was also an important prey item. There was an increase in the average prey size with growth in larvae ≤11.9 mm BL, while the number of prey eaten positively correlated with growth in larvae ≥12 mm BL. The trophic niche breadth also increased with larval growth, which would ensure a wide range of available food resources for the larger size-class larvae.

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Identification of medicinal plant Schisandra chinensis using a potential DNA barcode ITS2

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2013.032 ◽

2013 ◽

Vol 82 (4) ◽

pp. 283-288 ◽

Cited By ~ 8

Author(s):

Xian-kuan Li ◽

Bing Wang ◽

Rong-chun Han ◽

Yan-chao Zheng ◽

Hai-bo Yin Yin ◽

...

Keyword(s):

Dna Barcode ◽

Population Level ◽

Species Level ◽

Its2 Region ◽

Schisandra Chinensis ◽

Success Rates ◽

Wild Populations ◽

Efficient Tool ◽

Different Populations ◽

Cultivated Populations

To test whether the internal transcribed spacer 2 (ITS2) region is an effective marker for using in authenticating of the Schisandra chinensis at the species and population levels, separately. And the results showed that the wild populations had higher percentage of individuals that had substitution of C→A at site 86-bp than the cultivated populations. At sites 10-bp, 37-bp, 42-bp and 235-bp, these bases of the Schisandra sphenanthera samples differed from that of S. chinensis. Two species showed higher levels of inter-specific divergence than intra-specific divergence within ITS2 sequences. However, 24 populations did not demonstrate much difference as inter-specific and intra-specific divergences were concerned. Both S. chinensis and S. sphenanthera showed monophyly at species level, yet the samples of different populations shown polyphyly at population level. ITS2 performed well when using BLAST1 method. ITS2 obtained 100% identification success rates at the species level for S. chinensis, with no ambiguous identification at the genus level for ITS2 alone. The ITS2 region could be used to identify S. chinensis and S. sphenanthera in the “Chinese Pharmacopoeia”. And it could also correctly distinguish 100% of species and 100% of genera from the 193 sequences of S. chinensis. Hence, the ITS2 is a powerful and efficient tool for species identification of S. chinensis.

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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 composition and feeding habits of the eyespot skate, Atlantoraja cyclophora (Elasmobranchii: Arhynchobatidae), off Uruguay and northern Argentina

Neotropical Ichthyology ◽

10.1590/1982-0224-20160032 ◽

2016 ◽

Vol 14 (3) ◽

Cited By ~ 5

Author(s):

Santiago A. Barbini ◽

Luis O. Lucifora

Keyword(s):

Body Size ◽

Diet Composition ◽

Prey Size ◽

Prey Availability ◽

Feeding Habits ◽

Warm Season ◽

Cold Season ◽

The North ◽

Multiple Hypothesis ◽

Modelling Approach

ABSTRACT The eyespot skate, Atlantoraja cyclophora, is an endemic species from the southwestern Atlantic, occurring from Rio de Janeiro, Brazil, to northern Patagonia, Argentina. The feeding habits of this species, from off Uruguay and north Argentina, were evaluated using a multiple hypothesis modelling approach. In general, the diet was composed mainly of decapod crustaceans, followed by teleost fishes. Molluscs, mysidaceans, amphipods, isopods, lancelets and elasmobranchs were consumed in lower proportion. The consumption of shrimps drecreased with increasing body size of A. cyclophora. On the other hand, the consumption of teleosts increased with body size. Mature individuals preyed more heavily on crabs than immature individuals. Teleosts were consumed more in the south region (34º - 38ºS) and crabs in the north region (38º - 41ºS). Shrimps were eaten more in the warm season than in the cold season. Prey size increased with increasing body size of A. cyclophora , but large individuals also consumed small teleosts and crabs. Atlantoraja cyclophora has demersal-benthic feeding habits, shifts its diet with increasing body size and in response to seasonal and regional changes in prey availability and distribution.

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FEEDING HABITS AND HELMINTH PARASITES OF SARDINE (S. PILCHARDUS) AND ANCHOVY (E. ENCRASICOLUS) IN THE ADRIATIC SEA

Mediterranean Marine Science ◽

10.12681/mms.1467 ◽

2015 ◽

Vol 17 (1) ◽

pp. 216 ◽

Cited By ~ 3

Author(s):

B. ZORICA ◽

V. ČIKES KEČ ◽

O. VIDJAK ◽

I. MLADINEO ◽

D. EZGETA BALIČ

Keyword(s):

Diet Composition ◽

Feeding Habits ◽

Stomach Contents ◽

Stomach Content Analysis ◽

Helminth Parasites ◽

Significant Difference ◽

Prey Composition ◽

One Year ◽

Paratenic Hosts ◽

Hysterothylacium Aduncum

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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Feeding habits and trophic level of the smooth hammerhead shark, Sphyrna zygaena (Carcharhiniformes: Sphyrnidae), off Ecuador

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315418000474 ◽

2018 ◽

Vol 99 (3) ◽

pp. 673-680 ◽

Cited By ~ 2

Author(s):

Colombo Estupiñán-Montaño ◽

Luis Cedeño-Figueroa ◽

José F. Estupiñán-Ortiz ◽

Felipe Galván-Magaña ◽

Alejandro Sandoval-Londoño ◽

...

Keyword(s):

Trophic Level ◽

Feeding Habits ◽

Trophic Niche ◽

Commercial Fishing ◽

Dosidicus Gigas ◽

Apex Predators ◽

Marine Food Webs ◽

Fishing Vessels ◽

Marine Food ◽

Index Of Relative Importance

As apex predators, sharks are known to play an important role in marine food webs. Detailed information on their diet and trophic level is however needed to make clear inferences about their role in the ecosystem. A total of 335 stomachs of smooth hammerhead sharks, Sphyrna zygaena, were obtained from commercial fishing vessels operating in the Ecuadorian Pacific between January and December 2004. A total of 53 prey items were found in the stomachs. According to the Index of Relative Importance (%IRI), cephalopods were the main prey (Dosidicus gigas, Sthenoteuthis oualaniensis, Ancistrocheirus lesueurii and Lolliguncula [Loliolopsis] diomedeae). Sphyrna zygaena was thus confirmed to be a teutophagous species. The estimated trophic level of S. zygaena was between 4.6 and 5.1 (mean ± SD: 4.7 ± 0.16; males: 4.7; females: 4.8). Levin's index (BA) was low (overall: 0.07; males: 0.08; females: 0.09), indicating a narrow trophic niche. We found that sharks <150 cm in total length consumed prey of coastal origin, whereas sharks ≥150 cm foraged in oceanic waters and near the continental shelf. The analyses indicate that S. zygaena is a specialized predator consuming mainly squids.

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