Commonly Rare and Rarely Common: Comparing Population Abundance of Invasive and Native Aquatic Species

Hansen, Gretchen J. A.; Zanden, M. Jake Vander; Blum, Michael J.; Clayton, Murray K.; Hain, Ernie F.; Hauxwell, Jennifer; Izzo, Marit; Kornis, Matthew S.; McIntyre, Peter B.; Mikulyuk, Alison; Nilsson, Erika; Olden, Julian D.; Papeş, Monica; Sharma, Sapna

doi:10.1371/journal.pone.0077415

Cited by 71 publications

(70 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the River Meuse, for example, invading D. villosus accumulates to higher densities (200-500 individuals per artificial substrate) than the previous native-naturalised community (50-120 individuals per substrate), of which G. pulex was part (Josens et al 2005). This conforms to the general pattern of aquatic invasive species reaching higher densities, on average, than native analogues (Hansen et al 2013). Although per capita effects may increase nonadditively with density as a result of interference between conspecifics (Hassell 1978;Médoc et al 2015), increased densities will be associated with increased impact provided this multiple predator effect is not antagonistic.…”

Section: Villosussupporting

confidence: 64%

Size matters: predation of fish eggs and larvae by native and invasive amphipods

Taylor

Dunn

2016

Biol Invasions

View full text Add to dashboard Cite

Invasive predators can have dramatic impacts on invaded communities. Extreme declines in macroinvertebrate populations often follow killer shrimp (Dikerogammarus villosus) invasions. There are concerns over similar impacts on fish through predation of eggs and larvae, but these remain poorly quantified. We compare the predatory impact of invasive and native amphipods (D. villosus and Gammarus pulex) on fish eggs and larvae (ghost carp Cyprinus carpio and brown trout Salmo trutta) in the laboratory. We use size-matched amphipods, as well as larger D. villosus reflecting natural sizes. We quantify functional responses, and electivity amongst eggs or larvae and alternative food items (invertebrate, plant and decaying leaf). D. villosus, especially large individuals, were more likely than G. pulex to kill trout larvae. However, the magnitude of predation was low (seldom more than one larva killed over 48 h). Trout eggs were very rarely killed. In contrast, carp eggs and larvae were readily killed and consumed by all amphipod groups. Large D. villosus had maximum feeding rates 1.6-2.0 times higher than the smaller amphipods, whose functional responses did not differ.In electivity experiments with carp eggs, large D. villosus consumed the most eggs and the most food in total. However, in experiments with larvae, consumption did not differ between amphipod groups. Overall, our data suggest D. villosus will have a greater predatory impact on fish populations than G. pulex, primarily due to its larger size. Higher invader abundance could amplify this difference. The additional predatory pressure could reduce recruitment into fish populations.

show abstract

Section: Villosussupporting

confidence: 64%

Size matters: predation of fish eggs and larvae by native and invasive amphipods

Taylor

Dunn

2016

Biol Invasions

View full text Add to dashboard Cite

show abstract

“…Larger animals generally eat more, owing to positive relationships between body size and traits such as metabolic rate, reaction distance and exploratory speed (Brown et al 2004;Rall et al 2012;Hirt et al 2017). Second, aquatic alien species reach higher densities than natives on average (Hansen et al 2013), and this is probably the case for E. sinensis and P. leniusculus relative to A. pallipes (Guan 2000;Demers et al 2003;Rudnick et al 2003). The impact of a population of predators generally increases with abundance (Parker et al 1999), although the effect may be less than additive if mutual interference reduces the per capita impact of individual predators (Pintor et al 2009;Médoc et al 2013).…”

Section: Pacifastacus Leniusculusmentioning

confidence: 99%

Predatory impacts of alien decapod Crustacea are predicted by functional responses and explained by differences in metabolic rate

Taylor

Dunn

2018

Biol Invasions

View full text Add to dashboard Cite

Alien predators can have large impacts on prey. It is important that we understand, and ideally predict, these impacts. Here, we compare predatory impacts of size-matched decapod crustaceans-invasive alien Eriocheir sinensis and Pacifastacus leniusculus, and native European Austropotamobius pallipes-and use this case study to inform methods for impact prediction. We quantify functional responses (FRs) on three macroinvertebrate prey species, examine switching behaviour, and measure metabolic rates as a possible mechanistic explanation for differences in predation. FRs show a consistent pattern: attack coefficients and maximum feeding rates are ordered E. sinensis≥P. leniusculus≥A. pallipes for all prey species. Attack coefficients of E. sinensis are up to 6.7 times greater than those of size-matched crayfish and maximum feeding rates up to 3.0 times greater. FR parameters also differ between the invasive and native crayfish, but only up to 2.6 times. We find no evidence of switching behaviour in crayfish but suggestions of negative switching in E. sinensis. Differences in FR parameters are mirrored by differences in routine, but not standard, metabolic rate. Overall, our data predict strong predatory impacts of E. sinensis, even relative to alien P. leniusculus. Strong impacts of P. leniusculus relative to A. pallipes may be driven more by body size or abundance than per capita effect. FRs vary between prey types in line with existing knowledge of impacts, supporting the use of FRs in quantitative, prey-specific impact predictions. MRs could offer a general mechanistic explanation for differences in predatory behaviour and impacts.

show abstract

“…Certain traits of non‐redundancy demonstrated in the laboratory did scale up to more realistic mesocosms, many others did not, such as detritivory. However, invasive alien species (including decapods; Nyström, ; Hansen et al., ) are typically characterised by achieving high densities in their host ecosystems and this could amplify the impact of the effects observed in these mesocosm experiments.…”

Section: Discussionmentioning

confidence: 99%

Multi‐faceted impacts of native and invasive alien decapod species on freshwater biodiversity and ecosystem functioning

et al. 2018

View full text Add to dashboard Cite

Changes to species composition, such as biological invasions and extinctions, have the potential to alter ecosystems. Invaders often replace taxonomically similar species, resulting in potentially redundant impacts. For example, freshwater decapod crustaceans are pervasive invasive alien species but they often extirpate native decapods. This study addresses whether or not these compositional shifts lead to impacts on the structure of the macroinvertebrate community, key ecosystem functions such as decomposition rates and primary productivity, and freshwater properties such as turbidity. In a controlled outdoor mesocosm experiment that ran for 33 days, impacts on biodiversity, ecosystem functioning and properties were compared between a native, endangered crayfish (Austropotamobius pallipes) and two invasive alien decapods: the crayfish Pacifastacus leniusculus and crab Eriocheir sinensis. Equal densities of these decapod species were compared between mesocosms, with a replicated array of decapod free controls. Measurements included macroinvertebrate densities, decomposition of leaf litter, production of biofilms, plankton, macrophytes, gross primary productivity, turbidity, and dissolved nutrients. While taxonomic richness of non‐decapod macroinvertebrates was marginally higher in the invasive alien treatments, differences in Shannon diversity were negligible, and β‐diversity was higher for the invasive alien crab. Gastropod density was reduced in the benthos of invasive alien treatments. This was associated with increased primary productivity of periphyton, particularly in the presence of P. leniusculus. Increased turbidity was, however, inversely correlated with periphyton primary productivity in the E. sinensis treatment. Nitrate concentration was significantly lower in invasive compared to native crayfish mesocosms, but similar to decapod free controls. This reflects the potential for the invasive crayfish to act as a nitrogen sink, mediated through both enhanced periphyton and reduced nitrogen recycling. Other processes, such as decomposition rates, sediment respiration, community respiration, and gross primary productivity, did not differ between treatments. This study demonstrates impacts of both native and invasive alien decapod species on certain aspects of benthic biodiversity and ecosystem processes, but with many of these parameters unaffected. This assumes equal densities of each species in its environment. The enhanced gastropod predation and associated trophic cascade by invasive decapods are likely explained through higher consumption rates, metabolism and activity. These per‐capita impacts are likely to be exacerbated further in‐situ due to typically higher densities of invasive compared to native crayfish.

show abstract

Commonly Rare and Rarely Common: Comparing Population Abundance of Invasive and Native Aquatic Species

Cited by 71 publications

References 49 publications

Size matters: predation of fish eggs and larvae by native and invasive amphipods

Size matters: predation of fish eggs and larvae by native and invasive amphipods

Predatory impacts of alien decapod Crustacea are predicted by functional responses and explained by differences in metabolic rate

Multi‐faceted impacts of native and invasive alien decapod species on freshwater biodiversity and ecosystem functioning

Contact Info

Product

Resources

About