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Getting what is served? Feeding ecology influencing parasite-host interactions in invasive round goby Neogobius melanostomus.

Emde S, Kochmann J, Kuhn T, Plath M, Klimpel S - PLoS ONE (2014)

Bottom Line: However, the availability of amphipod species in the field did not reflect their relative abundance in gut contents of N. melanostomus.Only two metazoan parasites, the nematode Raphidascaris acus and the acanthocephalan Pomphorhynchus sp., were isolated from N. melanostomus in all months, whereas unionid glochidia were only detected in June and October in fish from the Main.Dikerogammarus villosus represented the most important amphipod prey for N. melanostomus in both rivers but parasite intensities differed between rivers, suggesting that final hosts (large predatory fishes) may influence host-parasite dynamics of N. melanostomus in its introduced range.

View Article: PubMed Central - PubMed

Affiliation: Institute for Ecology, Evolution and Diversity, Goethe-University, Frankfurt am Main, Hesse, Germany.

ABSTRACT
Freshwater ecosystems are increasingly impacted by alien invasive species which have the potential to alter various ecological interactions like predator-prey and host-parasite relationships. Here, we simultaneously examined predator-prey interactions and parasitization patterns of the highly invasive round goby (Neogobius melanostomus) in the rivers Rhine and Main in Germany. A total of 350 N. melanostomus were sampled between June and October 2011. Gut content analysis revealed a broad prey spectrum, partly reflecting temporal and local differences in prey availability. For the major food type (amphipods), species compositions were determined. Amphipod fauna consisted entirely of non-native species and was dominated by Dikerogammarus villosus in the Main and Echinogammarus trichiatus in the Rhine. However, the availability of amphipod species in the field did not reflect their relative abundance in gut contents of N. melanostomus. Only two metazoan parasites, the nematode Raphidascaris acus and the acanthocephalan Pomphorhynchus sp., were isolated from N. melanostomus in all months, whereas unionid glochidia were only detected in June and October in fish from the Main. To analyse infection pathways, we examined 17,356 amphipods and found Pomphorhynchus sp. larvae only in D. villosus in the river Rhine at a prevalence of 0.15%. Dikerogammarus villosus represented the most important amphipod prey for N. melanostomus in both rivers but parasite intensities differed between rivers, suggesting that final hosts (large predatory fishes) may influence host-parasite dynamics of N. melanostomus in its introduced range.

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Dikerogammarus villosus in fish guts and in the field.Numerical percentage of D. villosus in gut contents of N. melanostomus in relation to the relative abundance of D. villosus at the Main (black) and Rhine (grey) between June and October 2011.
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pone-0109971-g003: Dikerogammarus villosus in fish guts and in the field.Numerical percentage of D. villosus in gut contents of N. melanostomus in relation to the relative abundance of D. villosus at the Main (black) and Rhine (grey) between June and October 2011.

Mentions: Dikerogammarus villosus was disproportionally frequent in gut contents given its availability relative to that of other amphipod species on site (Chi2 goodness-of-fit tests, p<0.001; except for the July sampling in the Main when D. villosus overall was highly abundant in the field; Figure 1). Therefore, an additional ANCOVA with similar model structure was run using percentages of D. villosus in the gut content of N. melanostomus as the dependent variable (Table 3). Whereas a decrease (not increase) of numerical percentages of D. villosus in the gut content of N. melanostomus with increasing availability of D. villosus on site was found in the Main (driving a significant main effect of the covariate; Table 3), this pattern was not observed in the river Rhine (see significant interaction effect in Table 3; Figure 3).


Getting what is served? Feeding ecology influencing parasite-host interactions in invasive round goby Neogobius melanostomus.

Emde S, Kochmann J, Kuhn T, Plath M, Klimpel S - PLoS ONE (2014)

Dikerogammarus villosus in fish guts and in the field.Numerical percentage of D. villosus in gut contents of N. melanostomus in relation to the relative abundance of D. villosus at the Main (black) and Rhine (grey) between June and October 2011.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4206283&req=5

pone-0109971-g003: Dikerogammarus villosus in fish guts and in the field.Numerical percentage of D. villosus in gut contents of N. melanostomus in relation to the relative abundance of D. villosus at the Main (black) and Rhine (grey) between June and October 2011.
Mentions: Dikerogammarus villosus was disproportionally frequent in gut contents given its availability relative to that of other amphipod species on site (Chi2 goodness-of-fit tests, p<0.001; except for the July sampling in the Main when D. villosus overall was highly abundant in the field; Figure 1). Therefore, an additional ANCOVA with similar model structure was run using percentages of D. villosus in the gut content of N. melanostomus as the dependent variable (Table 3). Whereas a decrease (not increase) of numerical percentages of D. villosus in the gut content of N. melanostomus with increasing availability of D. villosus on site was found in the Main (driving a significant main effect of the covariate; Table 3), this pattern was not observed in the river Rhine (see significant interaction effect in Table 3; Figure 3).

Bottom Line: However, the availability of amphipod species in the field did not reflect their relative abundance in gut contents of N. melanostomus.Only two metazoan parasites, the nematode Raphidascaris acus and the acanthocephalan Pomphorhynchus sp., were isolated from N. melanostomus in all months, whereas unionid glochidia were only detected in June and October in fish from the Main.Dikerogammarus villosus represented the most important amphipod prey for N. melanostomus in both rivers but parasite intensities differed between rivers, suggesting that final hosts (large predatory fishes) may influence host-parasite dynamics of N. melanostomus in its introduced range.

View Article: PubMed Central - PubMed

Affiliation: Institute for Ecology, Evolution and Diversity, Goethe-University, Frankfurt am Main, Hesse, Germany.

ABSTRACT
Freshwater ecosystems are increasingly impacted by alien invasive species which have the potential to alter various ecological interactions like predator-prey and host-parasite relationships. Here, we simultaneously examined predator-prey interactions and parasitization patterns of the highly invasive round goby (Neogobius melanostomus) in the rivers Rhine and Main in Germany. A total of 350 N. melanostomus were sampled between June and October 2011. Gut content analysis revealed a broad prey spectrum, partly reflecting temporal and local differences in prey availability. For the major food type (amphipods), species compositions were determined. Amphipod fauna consisted entirely of non-native species and was dominated by Dikerogammarus villosus in the Main and Echinogammarus trichiatus in the Rhine. However, the availability of amphipod species in the field did not reflect their relative abundance in gut contents of N. melanostomus. Only two metazoan parasites, the nematode Raphidascaris acus and the acanthocephalan Pomphorhynchus sp., were isolated from N. melanostomus in all months, whereas unionid glochidia were only detected in June and October in fish from the Main. To analyse infection pathways, we examined 17,356 amphipods and found Pomphorhynchus sp. larvae only in D. villosus in the river Rhine at a prevalence of 0.15%. Dikerogammarus villosus represented the most important amphipod prey for N. melanostomus in both rivers but parasite intensities differed between rivers, suggesting that final hosts (large predatory fishes) may influence host-parasite dynamics of N. melanostomus in its introduced range.

Show MeSH
Related in: MedlinePlus