scholarly journals Composition and diversity of helminth communities in eels Anguilla anguilla in the River Tiber: long-term changes and comparison with insular Europe

1998 ◽  
Vol 72 (4) ◽  
pp. 301-306 ◽  
Author(s):  
C.R. Kennedy ◽  
F. Berrilli ◽  
D. Di Cave ◽  
C. De Liberato ◽  
P. Orecchia
Keyword(s):  
Anguilla Anguilla ◽  
Intestinal Helminth ◽  
European Eel ◽  
British Isles ◽  
Helminth Communities ◽  
Composition And Structure ◽  
Using Data ◽  
The Uk ◽  
Freshwater Eels

AbstractMost studies of helminth communities in the European eel Anguilla anguilla have been undertaken in the British Isles, and there are very few analyses of community composition and structure from continental Europe. To fill this gap and test the hypothesis that helminth communities in freshwater eels in the British Isles are not typical of those of continental Europe, helminth communities of eels in the River Tiber below Rome were analysed by season using data collected in 1980 and new data from 1996. The intestinal helminth communities in the Tiber eels were species poor and characterized by low diversity. Most eels harboured one or no parasite species and communities were heavily dominated by the acanthocephalan Acanthocephalus clavula. Intestinal helminth infra-community richness and diversity did not differ between seasons within a year or between the same seasons in 1980 and 1996, although some changes in composition were apparent. Intestinal infracommunities from Tiber eels were very similar in characteristics to those analysed from the British Isles, and their temporal changes also showed close similarities to those reported from rivers in the UK. It seems likely therefore that conclusions derived from British studies can be applied to helminth communities of eels on the continent.

Composition and structure of helminth communities in eels Anguilla anguilla from Italian coastal lagoons

1997 ◽  
Vol 71 (1) ◽  
pp. 35-40 ◽  
Author(s):  
C.R. Kennedy ◽  
D. Di Cave ◽  
F. Berrilli ◽  
P. Orecchia
Keyword(s):  
Coastal Lagoons ◽  
Anguilla Anguilla ◽  
Structural Similarity ◽  
Helminth Species ◽  
Community Level ◽  
Intestinal Helminth ◽  
Helminth Community ◽  
Component Community ◽  
Helminth Communities ◽  
Composition And Structure

AbstractThe composition and diversity of total and intestinal helminth component and infracommunities were determined in eels Anguilla anguilla from four shallow coastal lagoons near Rome. The lagoons differed principally in respect of their salinity. Only Lake Burano still received an input of freshwater, and both freshwater and marine helminth species were found in eels. In the other three lagoons all helminth species were marine or euryhaline and communities were dominated by digeneans. At component community level these three lagoons were far more similar to each other than to Lake Burano, but this distinction almost disappeared at infracommunity level. Species richness and diversity declined with increasing salinity at component community level but not at infracommunity level. Despite the changes and differences in helminth community composition, intestinal helminth infracommunity structure was very similar in all four lagoons and to that in eels from freshwater localities in Britain. The findings thus provide further and unexpected support for the view that some factor(s) other than supply side ones must be operating to produce the fundamental structural similarity in helminth communities in eels.

scholarly journals Helminth communities in eels Anguilla anguilla from Adriatic coastal lagoons in Italy

2001 ◽  
Vol 75 (1) ◽  
pp. 7-13 ◽  
Author(s):  
D. Di Cave ◽  
F. Berrilli ◽  
C. De Liberato ◽  
P. Orecchia ◽  
C.R. Kennedy
Keyword(s):  
Coastal Lagoons ◽  
Anguilla Anguilla ◽  
Marine Species ◽  
Intestinal Helminth ◽  
Helminth Communities ◽  
Composition And Structure ◽  
Order Of Magnitude ◽  
Adriatic Coast ◽  
Specialist Species ◽  
High Degree

The composition and diversity of the total and intestinal component and infra-communities were determined in eels Anguilla anguilla from three shallow lagoons on the Adriatic coast of Italy to determine whether the helminth communities would differ in composition and structure from those in eels from lagoons on the Tyrrhenian coast. The lagoons differed in respect of their management regimes and the extent of freshwater influx. Both freshwater and marine species of helminths were found in the eels in all three lagoons, but the freshwater component was richer in Valle Figheri. A suite of three digenean eel specialist species occurred in all three lagoons, of which any two members dominated each community. This conferred a high degree of similarity between the communities of the three lagoons. The same three species also dominated helminth communities in eels in lagoons along the Tyrrhenian coast of Italy, and compositional similarity levels were similar within and between western and eastern groups. Species richness was higher in the component communities of the eels of the Adriatic lagoons when compared to the Tyrrhenian ones, but diversity and dominance indices were of a similar order of magnitude and range. Intestinal helminth communities were richer and more diverse in two of the Adriatic lagoons because the proportion of eels with zero or one helminth species was, unusually, in the minority. It was nevertheless concluded that infracommunity structure was similar in eels from both western and eastern lagoons and that the hypothesis that it would differ in Adriatic lagoons could not be supported. The findings provide further evidence of the similarity in composition and structure of helminth communities in eels from coastal lagoons throughout Europe.

Richness and diversity of intestinal metazoan communities in brown trout Salmo trutta compared to those of eels Anguilla anguilla in their European heartlands

Parasitology ◽  
2000 ◽  
Vol 121 (1) ◽  
pp. 55-64 ◽  
Author(s):  
C. R. KENNEDY ◽  
R. A. HARTVIGSEN
Keyword(s):  
Community Structure ◽  
Brown Trout ◽  
Salmo Trutta ◽  
Interspecific Interactions ◽  
Anguilla Anguilla ◽  
Intestinal Helminth ◽  
Published Data ◽  
European Eel ◽  
Character Species ◽  
Helminth Communities

The hypothesis that intestinal helminth communities in freshwater brown trout are dissimilar in composition and structure to those in the European eel was tested by an analysis of component communities from 72 localities and of infracommunities from 34 localities in the British Isles and Norway. Derived indices were then compared with published data from eels. Composition of helminth communities differed considerably between the two hosts as a group of 4 species occurred commonly in trout and so gave greater predictability to the community composition. These 4 species were trout specialists and in 97% of the localities a trout specialist dominated the community rather than a generalist acanthocephalan as is typical for eels. By contrast all measures of community structure and indices of richness and diversity indicated that helminth communities in trout were isolationist in character, species poor and exhibited low diversity at both component and infracommunity levels. All values of indices for trout helminth communities were strikingly similar to those obtained from eels. Evidence of interspecific interactions within the trout helminth communities and a limit of 4 to infracommunity species richness further enhanced the similarities and suggested a common determinant of community structure. The hypothesis was thus supported in respect of species composition but refuted in respect of community structure.

Long-term stability in the richness and structure of helminth communities in eels, Anguilla anguilla, in Lough Derg, River Shannon, Ireland

2002 ◽  
Vol 76 (4) ◽  
pp. 315-322 ◽  
Author(s):  
C.R. Kennedy ◽  
C. Moriarty
Keyword(s):  
Community Diversity ◽  
Large Rivers ◽  
Small Rivers ◽  
Intestinal Helminth ◽  
Helminth Parasites ◽  
Component Community ◽  
Data Set ◽  
Helminth Communities ◽  
Composition And Structure ◽  
Acanthocephalus Lucii

AbstractA data set on intestinal helminth parasites was collected in the course of an 18 year investigation into the biology of eels in Meelick Bay, Lough Derg, River Shannon. This was used to test two hypotheses relating to the composition and structure of intestinal helminth communities, namely that eels in large rivers do not harbour richer and more diverse communities than those in small rivers but that community composition and structure are more stable over time than in small rivers. The helminth community was species poor, with only six species comprising the component community and a maximum infracommunity richness of three species. The community was overwhelmingly dominated by the acanthocephalan Acanthocephalus lucii, reflecting the importance of its intermediate host Asellus aquaticus in the eels' diet. The remaining helminth species contributed to species richness but made very little contribution to community diversity. Population levels of Acanthocephalus lucii fell and remained low between 1992 and 2000, probably reflecting increased movement of eels from other parts of the lough into Meelick Bay. Diversity values were low, but similar to those reported from other rivers in Britain and Europe. The results provided support for both hypotheses and indicated that in respect of richness, diversity and dominance, the helminth communities of eels in the River Shannon were typical of, and comparable to, those of other large rivers throughout Europe.

On the application of models of European eel (Anguilla anguilla) production and escapement to the development of Eel Management Plans: the River Severn

2007 ◽  
Vol 64 (7) ◽  
pp. 1472-1482 ◽  
Author(s):  
M. W. Aprahamian ◽  
A. M. Walker ◽  
B. Williams ◽  
A. Bark ◽  
B. Knights
Keyword(s):  
Reference Conditions ◽  
Anguilla Anguilla ◽  
European Eel ◽  
Silver Eel ◽  
Management Scenarios ◽  
Test Management ◽  
Management Measures ◽  
Silver Eels ◽  
Management Plans ◽  
The Uk

Abstract Aprahamian, M. W., Walker, A. M., Williams, B., Bark, A., and Knights, B. 2007. On the application of models of European eel (Anguilla anguilla) production and escapement to the development of Eel Management Plans: the River Severn. – ICES Journal of Marine Science, 64: 1472–1482. The European eel stock has declined significantly since the 1980s, and the Eel Recovery Plan of the European Commission requires Member States to develop river basin Eel Management Plans (EMPs) that will achieve an escapement of silver eels that equals or exceeds 40% of the escapement biomass that would be produced in the absence of human activities. However, because silver eel escapement is not quantified within the UK, a modelling approach is required to estimate potential and actual escapement, and to assess the likely effects of management measures. We focus on two approaches developed in the UK, the Reference Condition Model (RCM) and the Scenario-based Model for Eel Populations (SMEP), and illustrate how such approaches can be used in EMPs using selected data from the River Severn. The RCM results indicate that the yellow eel population in the River Severn basin may be just 30–40% of the potential density indicated by reference conditions derived from a selection of rivers between the late 1970s and the early 1980s. The challenges of applying a model designed to be as realistic of eel production as possible, and the limited data on natural eel habitat and eel production in the Severn, preclude a SMEP analysis similar to that of the RCM, but simulations based on a simplified basin description and eel survey data from the early 1980s illustrate the potential of this model to assess compliance and test management scenarios.

Long-term investigation of the composition and richness of intestinal helminth communities in the stocked population of eel, Anguilla anguilla, in Neusiedler See, Austria

Parasitology ◽  
2004 ◽  
Vol 130 (2) ◽  
pp. 185-194 ◽  
Author(s):  
M. SCHABUSS ◽  
C. R. KENNEDY ◽  
R. KONECNY ◽  
B. GRILLITSCH ◽  
F. SCHIEMER ◽  
...  
Keyword(s):  
Sampling Site ◽  
Anguilla Anguilla ◽  
Single Species ◽  
Parasite Community ◽  
Community Diversity ◽  
Intestinal Helminth ◽  
Infection Level ◽  
Component Community ◽  
Long Term Study

Data from a long-term study of the intestinal helminth parasite community of eels, Anguilla anguilla, stocked into the shallow eutrophic Neusiedler See, Austria, were collected over an 8 year period (1994–2001). In total, 720 eels from 2 sampling sites were examined. The parasite community showed characteristics similar to those in the natural eel populations in rivers of the UK and mainland Europe: it was species poor, with only 5 species (Acanthocephalus lucii, Acanthocephalus anguillae, Raphidascaris acus, Proteocephalus macrocephalus, Bothriocephalus claviceps) comprising the component community and a maximum infracommunity richness of 4 species. Over the period, the intestinal parasite community of the sampling site in Illmitz, which was originally dominated by A. lucii, changed. As levels of A. anguillae increased to a point at which it dominated the community, diversity increased whilst dominance of a single species decreased. By contrast the community in the southern sampling site remained rather constant with a continuous high infection level of A. anguillae and low abundance of A. lucii. Both acanthocephalan species exhibited higher infection levels in larger eels and in different seasons of the year and the infection parameters were significantly different between the years of study. The significant differences in the infection levels of the 2 acanthocephalan species at the 2 sampling sites were surprising as both acanthocephalan species use the same intermediate host, Asellus aquaticus, and the sampling sites were in close proximity and were similar in terms of water quality, host size and invertebrate abundance. Differences in the fish communities of the 2 sampling sites and eel movements rather than interspecific competition are discussed as possible explanations for the differences in the parasite communities of the 2 sampling sites.

scholarly journals Structure of intestinal helminth communities of the striped dolphin, Stenella coeruleoalba, in the western Mediterranean: a long-term analysis

2016 ◽  
Vol 3 ◽  
Author(s):  
Aznar Francisco ◽  
Sanz Tamarit Ruth ◽  
Mateu Puncel Paula ◽  
Cervera Estevan Carlos ◽  
Fraija Fernández Natalia ◽  
...  
Keyword(s):  
Western Mediterranean ◽  
Intestinal Helminth ◽  
Stenella Coeruleoalba ◽  
Striped Dolphin ◽  
Helminth Communities ◽  
Term Analysis

Effects of long-term exposure to hydrostatic pressure per se (101 ATA) on eel metabolism

1989 ◽  
Vol 67 (10) ◽  
pp. 1247-1251 ◽  
Author(s):  
B. Simon ◽  
P. Sebert ◽  
L. Barthelemy
Keyword(s):  
Hydrostatic Pressure ◽  
Anguilla Anguilla ◽  
Circulation System ◽  
Water Fish ◽  
Water Circulation System ◽  
State Formula ◽  
Pressure Water ◽  
Pressure Adaptation ◽  
Freshwater Eels

Oxygen consumption, [Formula: see text], has been measured in yellow freshwater eels (Anguilla anguilla L.) exposed in normoxic conditions for 31 days at a hydrostatic pressure of 101 ATA (atmosphere absolute; 1 ATA = 0.1 MPa) using a high pressure water circulation system. The results (series I) show that from a maximal value observed at the end of compression, [Formula: see text] decreases exponentially with time [Formula: see text] then reaches a steady state [Formula: see text] at a lower level than observed at 1 ATA before compression [Formula: see text]. These observations are in agreement with the hypothesis that shallow water fish are able to adapt to pressure; the possible mechanisms of this adaptation are discussed. Results from a second experimental series show that fish previously submitted to pressure for 1 month (then decompressed to 1 ATA) adjust faster to a new pressure exposure (4 days later) than fish that have never experienced pressure exposure. This observation suggests that the mechanisms triggered by long-term pressure exposure could persist, at least in part, for several days after decompression to atmospheric pressure.Key words: eel, metabolism, hydrostatic pressure, adaptation.

Sign in / Sign up

Export Citation Format

Share Document