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Rapid range extension of the Ponto-Caspian amphipod Dikerogammarus villosus in France: Potential consequences

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Abstract

Non-indigenous species are increasingly recognized as altering local communities in newly colonized areas. In some north European freshwater systems, the Ponto-Caspian invasive crustacean Dikerogammarus villosus (Amphipoda) is implicated to have such an effect, with general monitoring of its progress and general impact required. The present study contributes to this monitoring. D. villosus was observed in 2003 in all the major French rivers prospected (i.e. Rhine, Meuse, Moselle, Saône, Rhône, Seine, and Loire), a European region previously overlooked for its colonization. This species was also detected in some tributaries of the rivers Saône and Seine, and in Geneva Lake. The dynamics of this colonisation, inferred from samples made at different dates, show a rapid expansion westward, from its first appearance in the Saône in 1997. The colonised rivers are connected with the more important French harbours, which may facilitate future invasion of new countries. In two sites, D. villosus rapidly became the dominant crustacean species after its appearance. A comparison of the amphipod fauna between 2003 and ancient surveys also shows that some native species tend to disappear in the East of France. These data suggest an ongoing homogenisation process of amphipod assemblages.
Arch. Hydrobiol. 160 1 57–66 Stuttgart, May 2004
Rapid range extension of the Ponto-Caspian
amphipod Dikerogammarus villosus in France:
potential consequences
L. Bollache1*, S. Devin2, R. Wattier1, M. Chovet3, J.-N. Beisel2,
J.-C. Moreteau2and T. Rigaud1
With 2 figures and 1 table
Abstract: Non-indigenous species are increasingly recognized as altering local com-
munities in newly colonized areas. In some north European freshwater systems, the
Ponto-Caspian invasive crustacean Dikerogammarus villosus (Amphipoda) is im-
plicated to have such an effect, with general monitoring of its progress and general im-
pact required. The present study contributes to this monitoring. D. villosus was ob-
served in 2003 in all the major French rivers prospected (i. e. Rhine, Meuse, Moselle,
Saône, Rhône, Seine, and Loire), a European region previously overlooked for its co-
lonization. This species was also detected in some tributaries of the rivers Saône and
Seine, and in Geneva Lake. The dynamics of this colonisation, inferred from samples
made at different dates, show a rapid expansion westward, from its first appearance in
the Saône in 1997. The colonised rivers are connected with the more important French
harbours, which may facilitate future invasion of new countries. In two sites, D. villo-
sus rapidly became the dominant crustacean species after its appearance. A comparison
of the amphipod fauna between 2003 and ancient surveys also shows that some native
species tend to disappear in the East of France. These data suggest an ongoing homo-
genisation process of amphipod assemblages.
Key words: invasions, Dikerogammarus villosus, gammarids, French hydrosystem.
1Authors’ addresses: Equipe Ecologie Evolutive, UMR CNRS 5561 Biogéoscien-
ces, Université de Bourgogne, 6 boulevard Gabriel, 21000 Dijon, France.
2Equipe de Démoécologie, UR LBFE, Université de Metz, Campus Bridoux, avenue
du Général Delestraint, 57070 Metz, France.
3DIREN Centre, Service de l’eau et des milieux aquatiques, 5 avenue Buffon, BP
6407, 45064 Orléans Cedex 2, France.
* Author for correspondence; E-mail: loic.bollache@u-bourgogne.fr
DOI: 10.1127/0003-9136/2004/0160-0057 0003-9136/04/0160-0057 $ 2.50
2004 E. Schweizerbart’sche Verlagsbuchhandlung, D-70176 Stuttgart
... Its displacement of native species (MacNeil et al., 2011;MacNeil & Platvoet, 2013) also facilitates the establishment of other invasive alien species (Bollache et al., 2004;Leuven et al., 2009). Notably, it is the only invasive amphipod with documented monetary costs . ...
... Our study was therefore limited by our focus on rivers and streams. Dikerogammarus villosus also occurs in lentic freshwaters including lakes, ponds, and brackish waters, and has marked impacts on these ecosystems (Bacela-Spychalska et al., 2013;Bollache et al., 2004;Minchin et al., 2019). Its occurrence in other countries could also be underestimated, resulting in relatively few time series, for example the Netherlands or Switzerland (Altermatt et al., 2014;Bij de Vaate & Klink, 1995). ...
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Aim Invasive alien species are a growing problem worldwide due to their ecological, economic and human health impacts. The “killer shrimp” Dikerogammarus villosus is a notorious invasive alien amphipod from the Ponto‐Caspian region that has invaded many fresh and brackish waters across Europe. Understandings of large‐scale population dynamics of highly impactful invaders such as D. villosus are lacking, inhibiting predictions of impact and efficient timing of management strategies. Hence, our aim was to assess trends and dynamics of D. villosus as well as its impacts in freshwater rivers and streams. Location Europe. Methods We analysed 96 European time series between 1994 and 2019 and identified trends in the relative abundance (i.e. dominance %) of D. villosus in invaded time series, as well as a set of site‐specific characteristics to identify drivers and determinants of population changes and invasion dynamics using meta‐regression modelling. We also looked at the spread over space and time to estimate the invasion speed (km/year) of D. villosus in Europe. We investigated the impact of D. villosus abundance on recipient community metrics (i.e. abundance, taxa richness, temporal turnover, Shannon diversity and Pielou evenness) using generalized linear models. Results Population trends varied across the time series. Nevertheless, community dominance of D. villosus increased over time across all time series. The frequency of occurrences (used as a proxy for invader spread) was well described by a Pareto distribution, whereby we estimated a lag phase (i.e. the time between introduction and spatial expansion) of approximately 28 years, followed by a gradual increase before new occurrences declined rapidly in the long term. D. villosus population change was associated with decreased taxa richness, community turnover and Shannon diversity. Main Conclusion Our results show that D. villosus is well‐established in European waters and its abundance significantly alters ecological communities. However, the multidecadal lag phase prior to observed spatial expansion suggests that initial introductions by D. villosus are cryptic, thus signalling the need for more effective early detection methods.
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