scholarly journals First Occurrence of Eustrongylides spp. (Nematoda: Dioctophymatidae) in a Subalpine Lake in Northwest Italy: New Data on Distribution and Host Range

2020 ◽  
Vol 17 (11) ◽  
pp. 4171 ◽  
Author(s):  
Vasco Menconi ◽  
Maria Vittoria Riina ◽  
Paolo Pastorino ◽  
Davide Mugetti ◽  
Serena Canola ◽  
...  
Keyword(s):  
Host Range ◽  
Fish Species ◽  
Ictalurus Punctatus ◽  
Micropterus Salmoides ◽  
Perca Fluviatilis ◽  
Freshwater Ecosystems ◽  
Lepomis Gibbosus ◽  
Exact Test ◽  
Subalpine Lake ◽  
The Mean

The genus Eustrongylides includes nematodes that infect fish species and fish-eating birds inhabiting freshwater ecosystems. Nematodes belonging to the genus Eustrongylides are potentially pathogenic for humans; infection occurs after the consumption of raw or undercooked fish. In the two-year period 2019–2020, a total of 292 fish belonging to eight species were examined for the occurrence of Eustrongylides spp. from Lake San Michele, a small subalpine lake in northwest Italy. The prevalence of infestation was 18.3% in Lepomis gibbosus, 16.7% in Micropterus salmoides, and 10% in Perca fluviatilis. The other five fish species (Ameiurus melas, Ictalurus punctatus, Squalius cephalus, Carassius carassius, and Scardinius erythrophthalmus) were all negative for parasite presence. There were no significant differences in prevalence between the three fish species (Fisher’s exact test; p = 0.744). The mean intensity of infestation ranged from 1 (M. salmoides and P. fluviatilis) to 1.15 (L. gibbosus), and the mean abundance ranged from 0.1 (P. fluviatilis) to 0.28 (L. gibbosus). There were significant differences in the infestation site between the four muscle quadrants (anterior ventral, anterior dorsal, posterior ventral, and posterior dorsal) and the visceral cavity (Kruskal–Wallis test; p = 0.0008). The study findings advance our knowledge about the distribution and host range of this parasite in Italy.

scholarly journals Trophic Niches, Trophic Positions, and Niche Overlaps between Non-Native and Native Fish Species in a Subalpine Lake

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3475
Author(s):  
Davide Cicala ◽  
Gianluca Polgar ◽  
Jordi René Mor ◽  
Roberta Piscia ◽  
Stefano Brignone ◽  
...  
Keyword(s):  
Fish Species ◽  
Native Species ◽  
Perca Fluviatilis ◽  
Individual Variability ◽  
Freshwater Ecosystems ◽  
Native Fish ◽  
Isotopic Niche ◽  
Subalpine Lake ◽  
Trophic Traits ◽  
Trophic Niches

In the last century, Italian freshwater ecosystems have been invaded by several non-native fish species. In the subalpine Lake Mergozzo (northern Italy), several recently introduced non-native species dramatically expanded their populations. We used carbon and nitrogen stable isotopes to describe the isotopic niches and trophic positions of native and non-native fish species in Lake Mergozzo. We evaluated their trophic niches, trophic diversity, trophic redundancy and trophic evenness utilizing isotopic niche metrics, and estimated asymmetrical niche overlaps. The trophic traits of non-native fish species and Perca fluviatilis clearly define them as trophic generalists, in terms of among-individual variability of their isotopic niches. The historical increase in abundance of fish non-native species in this lake, their dominance by numbers and biomass within the assemblage, and their broad asymmetrical niche overlaps suggest that their higher degree of trophic generalism might have been one of the key factors that have promoted the invasion of the recipient community.

scholarly journals Pumpkinseed (Lepomis gibbosus L. 1758): Unwelcome inhibitant of ichthyofauna in the reservoir Strezevo in R. Macedonia

2011 ◽  
Vol 27 (4) ◽  
pp. 1531-1535
Author(s):  
R. Nastova ◽  
N. Nikolova
Keyword(s):  
Growth Rate ◽  
Fish Species ◽  
Flow Rate ◽  
Ecological Niche ◽  
Freshwater Ecosystems ◽  
Low Flow ◽  
Lepomis Gibbosus ◽  
Good Growth ◽  
Introduced Fish ◽  
Competition For Space

Pumpkinseed (Lepomis gibbosus L. 1758) represents an allochthonous (introduced) fish species in freshwater ecosystems of Europe. It has shown good adaptation to existing ecological conditions in the back and low flow rate waters. The analysis of some ecological characteristics of the samples, taken from the reservoir Strezevo in R. Macedonia, points to extremely good growth rate in this ecosystem. Despite markedly expressed fluctuations in the number of its population, pumpkinseed has occupied a corresponding ecological niche in the littoral part of habitat. However, due to a wide trophic spectrum and the possible competition for space and places for reproduction, pumpkinseed has become overabundant, thereby deteriorating the ichthyofauna and state in reservoir Strezevo.

scholarly journals Assessment of Potential Toxic Elements in Muscle Tissues of Different Fish Species from Colentina, Dambovita and Arges Rivers, Romania

2001 ◽  
Vol 71 (3) ◽  
pp. 19-28 ◽  
Author(s):  
Petra Ionescu ◽  
Violeta-Monica Radu ◽  
Gyorgy Deak ◽  
Elena Diacu ◽  
Alexandru Anton Ivanov ◽  
...  
Keyword(s):  
Human Health ◽  
Fish Species ◽  
Toxic Elements ◽  
Perca Fluviatilis ◽  
Point Of View ◽  
Lepomis Gibbosus ◽  
Toxic Substances ◽  
Potential Toxic Elements ◽  
Ameiurus Nebulosus ◽  
Muscle Tissues

At global level, anthropic activities have led to the emergence in the environment of different toxic substances, which tend to accumulate within the food chain, thus presenting risks to human health. As a result, the assessment of potentially toxic elements, particularly heavy metals, in fish is highly important from the point of view of human health as fish is frequently consumed by people. This paper presents the results of a study on determining some potential toxic elements such as Cd, Pb, Hg, Cu, Cr, Ni and Zn in muscle tissue resulting from six different fish species (Alburnus alburnus, Carassius gibelio, Scardinius erythrophthalmus, Ameiurus nebulosus, Perca fluviatilis, Lepomis gibbosus) from the Colentina, Dambovita and Arges Rivers situated in southern Romania area, and to compare the results with the relevant international guidelines.

scholarly journals Could Fish Feeding Behaviour and Size Explain Prevalence Differences of the Nematode Eustrongylides excisus among Species? The Case Study of Lake Garda

Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3581
Author(s):  
Vasco Menconi ◽  
Perla Tedesco ◽  
Paolo Pastorino ◽  
Ivano Confortini ◽  
Giuseppe Esposito ◽  
...  
Keyword(s):  
Fish Species ◽  
Micropterus Salmoides ◽  
Perca Fluviatilis ◽  
Trophic Levels ◽  
Coregonus Lavaretus ◽  
Intermediate Hosts ◽  
Piscivorous Fish ◽  
Lake Garda ◽  
Rdna Sequences

The nematode Eustrongylides excisus is a parasite of freshwater fish- and fish-eating birds, with known differences on prevalence values among fish species. Thus, the present study aims to explore the hypothesis that the feeding behavior and the size of fish belonging to different trophic levels could explain such differences. For that, 14 sampling sites were selected to perform a fish parasitological survey on Lake Garda (Italy) during spring-summer 2020. Amplification of nuclear ribosomal internal transcribed spacer (ITS) rDNA sequences of nematodes morphologically ascribable to the genus Eustrongylides allowed to identify them as E. excisus. From the five studied fish species (Perca fluviatilis, Lepomis gibbous, Coregonus lavaretus, Alosa fallax lacustris and Micropterus salmoides), only three presented the parasite E. excisus: P. fluviatilis, L. gibbous and M. salmoides, with significant differences in prevalence values among species (p = 0.002). Additionally, there were differences in prevalence values within the same fish species captured from different sampling sites. Findings showed that mainly piscivorous fish were positive for E. excisus and how the prevalence was highest in M. salmoides. As regard the fish size, a negative correlation between body size and E. excisus was found in P. fluviatilis due to the feeding habit of juvenile perch which feed mainly zooplankton and benthic invertebrates (i.e., oligochaetes, which are the first intermediate hosts of E. excisus). The study findings advance novel knowledge in the field of pathogens of zoonotic importance in the aquatic environment.

Model selection for fish growth patterns based on a Bayesian approach: A case study of five freshwater fish species

2020 ◽  
Vol 33 ◽  
pp. 17
Author(s):  
Kui Zhang ◽  
Jun Zhang ◽  
Jiajun Li ◽  
Baochao Liao
Keyword(s):  
Model Selection ◽  
Growth Model ◽  
Fish Species ◽  
Micropterus Salmoides ◽  
Freshwater Ecosystems ◽  
Growth Patterns ◽  
Fish Growth ◽  
Model Parameters ◽  
Prediction Ability ◽  
Commercial Fish

Selecting an appropriate growth pattern for individual fish is a meaningful but complex topic in fishery research. We model four growth functions − the commonly used von Bertalanffy growth model (VBGM), and the Gompertz growth model (GGM), Schnute–Richards growth model (SRGM), and generalized VBGM (G-VBGM) − to examine possible growth patterns. Mean total length-at-age fish datasets for five commercial fish species (yellow perch Perca flavescens, walleye Sander vitreus, northern pike Esox lucius, largemouth bass Micropterus salmoides and lake herring Coregonus artedi) from North American freshwater ecosystems, were analyzed. Using a Markov chain Monte Carlo (MCMC) algorithm, we structured four models combining informative priors of model parameters. It is the first time that deviance information criterion (DIC) and leave-one-out cross-validation (LOOCV) were combined to select the best growth model. During the model-selection process, the smooth LOOCV error successfully followed the trend of the LOOCV error, although there were difference in the curve shapes. Values of scale reduction factor (SRF) for all four models indicated convergence, ranging 1.02–1.06, below the 1.2 threshold. The GGM was selected for C. artedi, and the G-VBGM for the other four species. Our approach provided a robust process in model-selection uncertainty analysis, with the G-VBGM having the best prediction ability among our datasets.

Factors Related to the Biomass and Production of Fish Communities in Small, Oligotrophic Lakes Vulnerable to Acidification

1991 ◽  
Vol 48 (12) ◽  
pp. 2523-2532 ◽  
Author(s):  
J. R. M. Kelso ◽  
M. G. Johnson
Keyword(s):  
Fish Species ◽  
Yellow Perch ◽  
Fish Community ◽  
Micropterus Salmoides ◽  
Acid Neutralizing Capacity ◽  
Lepomis Gibbosus ◽  
Fish Biomass ◽  
Total Biomass ◽  
Community Biomass ◽  
Neutralizing Capacity

We estimated biomass and production of the fish community in 19 small (<50 ha) lakes from four watersheds in central Ontario. Lake pH ranged from 4.8 to 7.1. We found 19 fish species in these lakes; yellow perch (Perca flavescens), pumpkinseed (Lepomis gibbosus), white sucker (Catostomus commersoni), and largemouth bass (Micropterus salmoides) were the most common. On average, there were 4.5 species per lake. Neither fish community biomass nor production was significantly different among the communities identified by cluster analysis, and the number offish species was not lower at lower pH. More than 75% of each lake's total biomass was confined to less than three fish species. Whole-lake fish biomass was related to the total number of species in the lakes and their average age. Fish community production was related to fish biomass, averge fish size, and acid neutralizing capacity (ANC) with an almost equal influence provided by each factor. At lower ANC and pH, fish were usually smaller in weight and often had lower population growth rates. In these lakes where the influence of lake size and trophic status was minimized, fish community biomass and production were only secondarily related to lake pH or ANC.

scholarly journals The fishfauna of the Crişul Repede river and its threatening major factors

2007 ◽  
pp. 13-18
Author(s):  
Ilie C. Telcean ◽  
Diana Cupşa ◽  
S. D. Covaciu-Marcov ◽  
I. Sas
Keyword(s):  
Ictalurus Punctatus ◽  
Micropterus Salmoides ◽  
Clarias Gariepinus ◽  
Lepomis Gibbosus ◽  
Acipenser Ruthenus ◽  
Ictalurus Nebulosus ◽  
Ictalurus Melas ◽  
Major Factors ◽  
The Impact ◽  
Negative Factors

The Crişul Repede River is belonging at Cris (Körös) Rivers system which is a tributary on the left shore of Tisa River. In the last decades the fishfaunaofthenaturalwatershasundergoingadeclineinthespeciesnumber.Theothersuccessiveprocessisthefishspeciesreplacement due by the immigration of some exotically fishesandtheretirementofsomeofthenativespecies.The Crişul Repede fishfaunahasregisteredadeclinecausedmainlybytheriverdamming,waterpollutionandeutrophisation.Ondespite of that negative factors the fishesfromtheupperriverwasmaintainlessaffectedunliketotheotherrivers.Thereaftertheeconomical transition and the industries reorganization process were redounded to diminishing the impact of these harmful factors. The former studies about the Cris fishfaunacitedanumberof48nativespeciesand12exoticones.Duringtheresearchtripscarriedoutsince10yearsago (beginning in 1995) was identifiedanumberof40fishspeciesandthepresenceoftheother8 speciesarestilluncertain.Thesturgeonspecies Acipenser ruthenus and the migratory fishAnguillaanguillahaveascarcepresenceandtheycannotbefoundinthelastdecade.A number of 5 exotically fishesarebehavedasremarkableintrudersinnaturalwaters:Pseudorasboraparva,Carassiusauratusgibelio,Ictalurus nebulosus, Ictalurus melas, and Lepomis gibbosus. Some of the exotically fishesalreadyrecordedintheHungarianstretchesofthe Crisuri (Körös) was not recorded in the Romanian section of the river (Mylopharyngodon piceus, Ictiobus bubalus, Ictalurus punctatus, Clarias gariepinus, Micropterus salmoides, Oreochromis niloticus, Perccottus glenii). The pervading of these species is expecting also in the Romanian section of the rivers.The present major threatening factors concerning the fishfaunaarerepresentedbythehabitatchanges.Theriverdammingandtheriverside levees have a negative influenceonthefishfauna.Theformerphenomenonofwaterpollutionitseemsthatisreplacedbythehabitat changes. The dam lakes caused unregulated fluctuationsonthewaterlevelandtemperaturedownstreamofit.Theembankmentforpreventing the floodingwasperformedthroughshorteningtherivermeander.Thelostmeandersoftheriversarerepresentinganoptimalhabitat for fishspawning.

scholarly journals Bioaccumulation of potentially toxic elements in fish species from aquatic environments located in crowded areas of southern Romania

2019 ◽  
Vol 1 ◽  
pp. 53-58 ◽  
Author(s):  
P Ionescu ◽  
V M Radu ◽  
Gy Deak ◽  
I E Ciobotaru ◽  
E Marcu ◽  
...  
Keyword(s):  
Fish Species ◽  
Toxic Elements ◽  
Perca Fluviatilis ◽  
Fish Tissue ◽  
Potentially Toxic Elements ◽  
Lepomis Gibbosus ◽  
Aquatic Environments ◽  
Potential Toxic Elements ◽  
Scardinius Erythrophthalmus ◽  
Carassius Gibelio

Taking into consideration that fish are valuable bioindicators for assessing pollution with potentially toxic elements (PTEs) such as heavy metals from aquatic environments, this study aimed to assess bioaccumulation factors in relation to water (BAF) and sediment (BASF) for the following potential toxic elements: Cd, Pb, Hg, Cu, Cr, Ni and Zn from 6 different fish species (Alburnus alburnus, Carassius gibelio, Scardinius erythrophthalmus, Ameiurus nebulosus, Perca fluviatilis, Lepomis gibbosus). Fish species have been captured from the waters of the Arges River (Hotarele village area) and the Colentina River (particularly from Mogosoaia, Herastrau and Panteliom lakes), from crowded areas located in the southern part of Romania. The results of the analysis indicated BAF values > 1 for the most fish species captured from the Colentina River. BASF values > 1 were obtained for BASFPb (Carassius gibelio - Arges River), BASFNi (Scardinius erythrophthalmus - Herastaru L. and Perca fluviatillis - Pantelimon L.), BASFCr (Perca fluviatillis - Pantelimon L.) and BASFZn (Alburnus alburnus and Scardinius erythrophthalmus - Mogosoaia L. and Carassius gibelio - Pantelimon L.). The obtained results can be used to describe the transfer of these elements from water and sediments to the fish tissue.

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