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Success factors and future prospects of Ponto–Caspian peracarid (Crustacea: Malacostraca) invasions: Is ‘the worst over’?

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  • Danube Research Institute, MTA Centre for Ecological Research
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Abstract and Figures

Ponto–Caspian peracarids (amphipods, isopods, mysids and cumaceans) represent one of the most successful groups of aquatic invaders comprising several high-impact species, such as Chelicorophium curvispinum, Dikerogammarus villosus, or Hemimysis anomala. In the present study we made the first attempt to compare biological traits and the environmental preferences of invasive and non-invasive members of the group based on both literature and field data (Joint Danube Survey 3, 2013) with the goal of identifying factors linked to invasion success and drawing conclusions on future invasion risks. Both datasets indicated substrate preference as an important factor in spontaneous range expansion; all invasive species are lithophilous, whereas the majority of non-invasives are psammo-pelophilous. The remaining seven presently non-invasive lithophilous species deserve special attention when considering potential future invaders; however, due to their rarity and possible negative interactions with earlier colonists we consider the probability of their expansion in the foreseeable future as low. Their potential expansion could most likely be of minor consequence anyway, since no considerable functional novelty can be attributed to them in addition to species already present. In this limited context (regarding habitats dominated by hard substrates and not considering the potential further spread of already invasive species) it might be justified to conclude that ‘the worst is over’. Nevertheless, impending navigation development projects both in the Danube–Main–Rhine and Dnieper–Pripyat–Bug–Vistula systems might favour the future spread of non-lithophilous species, which might imply a new invasion wave of Ponto–Caspian peracarids.
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ORIGINAL PAPER
Success factors and future prospects of Ponto–Caspian
peracarid (Crustacea: Malacostraca) invasions:
Is ‘the worst over’?
Pe
´ter Borza .Thomas Huber .Patrick Leitner .
Nadine Remund .Wolfram Graf
Received: 21 April 2016 / Accepted: 30 January 2017 / Published online: 8 February 2017
ÓSpringer International Publishing Switzerland 2017
Abstract Ponto–Caspian peracarids (amphipods,
isopods, mysids and cumaceans) represent one of the
most successful groups of aquatic invaders comprising
several high-impact species, such as Chelicorophium
curvispinum,Dikerogammarus villosus, or Hemimysis
anomala. In the present study we made the first
attempt to compare biological traits and the environ-
mental preferences of invasive and non-invasive
members of the group based on both literature and
field data (Joint Danube Survey 3, 2013) with the goal
of identifying factors linked to invasion success and
drawing conclusions on future invasion risks. Both
datasets indicated substrate preference as an important
factor in spontaneous range expansion; all invasive
species are lithophilous, whereas the majority of non-
invasives are psammo-pelophilous. The remaining
seven presently non-invasive lithophilous species
deserve special attention when considering potential
future invaders; however, due to their rarity and
possible negative interactions with earlier colonists we
consider the probability of their expansion in the
foreseeable future as low. Their potential expansion
could most likely be of minor consequence anyway,
since no considerable functional novelty can be
attributed to them in addition to species already
present. In this limited context (regarding habitats
dominated by hard substrates and not considering the
potential further spread of already invasive species) it
might be justified to conclude that ‘the worst is over’.
Nevertheless, impending navigation development
projects both in the Danube–Main–Rhine and Dnie-
per–Pripyat–Bug–Vistula systems might favour the
future spread of non-lithophilous species, which might
imply a new invasion wave of Ponto–Caspian
peracarids.
Keywords Amphipoda Colonization rate
Cumacea Isopoda Mysida Substrate preference
Introduction
Predicting future invasions by identifying traits of
species determining invasion success is a fundamental
endeavor of applied ecology (Williamson and Fitter
1996; Kolar and Lodge 2001; Heger and Trepl 2003).
Initial attempts at finding features universally
P. Borza (&)
Danube Research Institute, MTA Centre for Ecological
Research, Karolina u
´t 29-31, Budapest 1113, Hungary
e-mail: borza.peter@okologia.mta.hu
T. Huber P. Leitner W. Graf
Working Group on Benthic Ecology and Ecological Status
Assessment, Department of Water, Atmosphere and
Environment, Institute for Hydrobiology and Water
Management, BOKU - University of Natural Resources
and Applied Life Sciences, Max Emanuel-Strasse 17,
1180 Vienna, Austria
N. Remund
Info Fauna – CSCF, Passage Maximilien-de-Meuron 6,
2000 Neucha
ˆtel, Switzerland
123
Biol Invasions (2017) 19:1517–1532
DOI 10.1007/s10530-017-1375-7
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... To the extent of our knowledge, a comprehensive list of these species along with their taxonomic and ecomorphological diversity, as well as modes of introduction has never been compiled. Such information is, again, of high relevance in forecasting future invasions (Borza et al. 2017). ...
... The first two are more associated with coarse substrates (fine sand to rocks) than the last two (Copilaș-Ciocianu and Sidorov 2022). An affinity for hard substrata has been proposed as an important factor favoring the dispersal of Ponto-Caspian peracarid crustaceans into heavily anthropized habitats (Borza et al. 2017). Indeed, numerous studies reported a preference of alien Ponto-Caspian amphipods for hard substrates, although relatively few species were studied thus far (Dermott et al. 1998;Hesselschwerdt et al. 2008;Jermacz et al. 2015;Borza et al. 2018;Poznańska-Kakareko et al. 2021). ...
... Prospects for further dispersal Europe and temperate Asia are the most affected regions by alien crustacean species, and their number is predicted to significantly rise by 2050 (Seebens et al. 2021). Borza et al. (2017) concluded that the possibility for additional Ponto-Caspian peracarid crustaceans of becoming invasive in the future is low. Nevertheless, given that the current number of nonnative species is already quite high, further dispersal into new regions is unavoidable. ...
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... Peracarid crustaceans represent the most diverse group of Ponto-Caspian invaders with considerable ecological impacts in the North-Atlantic region (Gallardo and Aldridge 2015;Pagnucco et al. 2015;Borza et al. 2017a). The previous surveys have already made a significant contribution to our knowledge about their distributional patterns (Borza et al. 2010(Borza et al. , 2015(Borza et al. , 2017a as well as their ecological interactions (Borza et al. 2017b(Borza et al. , 2018a. ...
... Peracarid crustaceans represent the most diverse group of Ponto-Caspian invaders with considerable ecological impacts in the North-Atlantic region (Gallardo and Aldridge 2015;Pagnucco et al. 2015;Borza et al. 2017a). The previous surveys have already made a significant contribution to our knowledge about their distributional patterns (Borza et al. 2010(Borza et al. , 2015(Borza et al. , 2017a as well as their ecological interactions (Borza et al. 2017b(Borza et al. , 2018a. In this paper, we present the faunistic results of the fourth survey pertaining to this group. ...
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... Several Ponto-Caspian amphipods (Dikerogammarus villosus (Sowinski, 1894), Dikerogammarus haemobaphes (Eichwald, 1841), Echinogammarus ischnus (Stebbing, 1899), Chelicorophium curvispinum (G.O. Sars, 1895)) are associated with hard substrata, such as stones, coarse gravel and solid artificial objects (Muskó, 1993;Dermott et al., 1998;Devin et al., 2003;Van Overdijk et al., 2003;Kobak et al., 2015;Borza et al., 2017a). Other species, such as Pontogammarus robustoides (G.O. ...
... All the amphipods studied except P. robustoides were strongly associated with stony substrata. This confirms earlier experimental and field observations on D. villosus Kobak et al., 2015;Borza et al., 2017a), D. haemobaphes (Muskó, 1993;Wawrzyniak-Wydrowska and Gruszka, 2005;Muskó et al., 2007) and E. ischnus (Dermott et al., 1998). It should be noted that all stones in our study area were fouled by the zebra mussel, definitely modifying the conditions for the bottom fauna. ...
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... Under combined pressures (especially 'navigation' and 'channelization') the metric correlations revealed a critical community turnover in terms of neozoa outnumbering EPT taxa and the ratio of hemilimnic individuals decreasing. The issue of navigation and channelization and its association with neozoa is well documented in several studies (e.g. as already observed by Liebmann and Reichenbach-Klinke, 1967), particularly caused by wave action (Winnell and Jude, 1991;Graf et al., 2015) eliminating native taxa (Borza et al., 2017). The replacement of the sensitive native fauna by insensitive and rapidly spreading non-native taxa thriving in humanaltered environments ultimately renders "spatially homogenized" invertebrate communities with much lower species diversity (Fittkau and Reiss, 1983, Zwick, 1984, Fochetti and Tierno de Figueroa, 2008. ...
... The replacement of the sensitive native fauna by insensitive and rapidly spreading non-native taxa thriving in humanaltered environments ultimately renders "spatially homogenized" invertebrate communities with much lower species diversity (Fittkau and Reiss, 1983, Zwick, 1984, Fochetti and Tierno de Figueroa, 2008. Non-native taxa are successfully spreading primarily in navigated watercourses across Europe (Borza et al., 2017(Borza et al., , 2018, but they are still not considered as a discrete metric in existing bioassessment Table 2 Spearman's rho correlations (2-tailed) between selected metrics and pressures; * Correlation is significant at the p ≤ 0.05 level; ** Correlation is significant at the p ≤ 0.01 level in bold; n.s.: not significant; total number of samples = 1197; n = number of cases for analyses used for each pressure (due to exclusion of missing values). ...
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The Danube between Harta (rkm 1549) and Kehlheim (rkm 2410) was sampled qualitatively in 1985-1995 at all seasons. Eighteen epigean species of Malacostraca (Janiridae, Asellidae, Gammaridae, Talitridae, Corophiidae, Mysidae, Astacidae, Cambaridae) were recorded. The malacostracan fauna shows a distinct longitudinal zonation in the River Danube. At least nine species are of Ponto-Caspian origin. The actual distribution patterns were analyzed with respect to former studies. At least six species were strongly expansive during the last few decades. Navigation appears to be among the crucial factors for this dispersion.
Article
The River Danube plays a central role in the spread of Ponto-Caspian species as a part of the so-called southern invasion corridor (Danube-Main-Rhine system); therefore, changes in its peracarid fauna (comprising the bulk of invasives) merit special attention. The latest international research expedition (Joint Danube Survey 3, 2013) offered an opportunity for updating and synthesizing our knowledge about this group along the Danube, previously based on studies covering only certain river sections and/or dealing with a subset of species. Altogether 17 amphipod, 7 mysid, 3 isopod, and one cumacean species were recorded at 55 sites investigated between Ulm (river km 2581) and the Delta. Recent large-distance expansion of additional Ponto-Caspian species was not observed, but three species (Chelicorophium robustum, C. sowinskyi, and Echinogammarus trichiatus) have been able to shorten their distributional gap in the Middle Danube, E. trichiatus being recorded for the first time in Serbia. Ponto-Caspian peracarids are still gradually advancing in the German section, as well, implying retreat of native Gammarus spp., and impeding the spread of non-Ponto-Caspian invaders. On the contrary, some Ponto-Caspian species seem to have declined in certain river sections; Dikerogammarus bispinosus was entirely missing in the Lower Danube, and several species characteristic of the lower reaches had been recorded previously much farther upstream (most notably Chelicorophium maeoticum and Obesogammarus crassus). The analysis of current and historical distributional patterns revealed that the crucial step in the large-scale spread of Ponto-Caspian species is crossing the section between Baja and the Sava estuary (rkm ~1480 –1170) – characterized by an unfavorable combination of relatively strong currents and fine bed material – by passive transport. Presence immediately downstream of this section does not appear to promote further expansion in most of the cases; the source region of large-distance dispersal is most likely the Delta, implying that potential future invaders cannot be identified based on their previous expansion in the lower reaches of the river.