Effects of Ficopomatus enigmaticus ecosystem‐engineered habitat structure on population parameters of the amphipod Melita palmata : A NIS‐NIS interaction study (original) (raw)

2020, Marine Ecology

https://doi.org/10.1111/MAEC.12587

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Abstract

In biological invasion processes, changes in habitat structure induced by non-indigenous ecosystem engineers (organisms that modify, maintain, or create a new habitat or habitat structure, Jones, Lawton, & Shachak, 1994) represent a decisive pathway of cascade effects on native communities (e.g., Burlakova,

Invasive species contribute to biotic resistance: negative effect of caprellid amphipods on an invasive tunicate

Biological Invasions, 2014

As the number of introductions of nonindigenous species (NIS) continues to rise, ecologists are faced with new and unique opportunities to observe interactions between species that do not naturally co-exist. These interactions can have important implications on the invasion process, potentially determining whether NIS become widespread and abundant, survive in small numbers, or fail to establish and disappear. Although many studies have naturally focused on the interactions between NIS and native species to examine their effects and the biological resistance of the recipient community to invasion, few have examined the effects that NIS have on each other. In some cases, interactions can facilitate the invasion process of one or both species (i.e., ''invasional meltdowns''), but competition or predation can lead to negative interactions as well. The introduction of the vase tunicate, Ciona intestinalis, in Prince Edward Island (Canada) has harmed mussel aquaculture via heavy biofouling of equipment and mussels. Through both a broad-scale survey and small-scale field experiments, we show that Ciona recruitment is drastically reduced by caprellid amphipods, including the NIS Caprella mutica. This study provides an exciting example of how established invasive species can negatively impact the recruitment of a secondary invader, highlighting the potential for non-additive effects of multiple invasions.

Habitat complexity and community composition: relationships between different ecosystem engineers and the associated macroinvertebrate assemblages

2011

Several species of ecosystem engineers inhabiting coastal environments have been reported structuring different kinds of communities. The magnitude of this influence often depends on the habitat complexity introduced by the engineers. It is commonly accepted that an increase in habitat complexity will result in an increase in diversity and/or abundance in the associated fauna. The rocky salt marshes along the coast of Patagonia are dominated by cordgrasses, mussels, and barnacles forming a mosaic of engineered habitats with different complexity. This system allows us to address the following questions: how different is a macroinvertebrate assemblage when dominated by different ecosystem engineers? And, is there a positive relationship between increasing habitat complexity and the species richness, diversity and total density of the assemblages? To address these questions, we compared the three ecological scenarios with decreasing habitat complexity: cordgrass-mussel, mussel, and barnacle-engineered habitats. We found a total of 22 taxa mostly crustaceans and polychaetes common to all scenarios. The three engineered habitats showed different macroinvertebrate assemblages, mainly due to differences in individual abundances of some taxa. The cryptogenic amphipod Orchestia gammarella was found strictly associated with the cordgrass-mussel habitat. Species richness and diversity were positively related with habitat complexity while total density showed the opposite trend. Our study suggests that species vary their relative distribution and abundances in response to different habitat complexity. Nevertheless, the direction (i.e., neutral, positive or negative) and intensity of the community's response seem to depend on the physiological requirements of the different species and their efficiency to readjust their local spatial distribution in the short term.

Studying exotics in their native range: Can introduced fouling amphipods expand beyond artificial habitats?

Biological Invasions, 2016

Knowledge of the habitat use patterns of introduced species in their native or naturalized range can provide unique insights into processes of secondary dispersal and colonization of natural habitats. Caprellid amphipods are small mobile marine epibionts with limited natural dispersal. The global distribution of some caprellid species is mostly the result of anthropogenic transport; however, their subsequent spread beyond artificial habitats is poorly understood. A biogeographic approach, mainly focused on the native-range ecology of introduced and common fouling caprellid amphipods of southern Europe, was used to understand the implications of habitat use patterns for predicting their spread in the introduced regions. Specifically, abundance and composition of caprellid populations were compared among different primary habitats including artificial (floating pontoons), sheltered and wave-exposed rocky shores along the southern and southeastern coasts of Brazil. The findings indicated that artificial habitats act as reservoirs for globally distributed species in both their native and introduced ranges, while endemic species are more scarcely represented. Environmental conditions provided by primary habitats appear important in structuring caprellid assemblages on secondary substrata (basibiont species). Most wide-ranging caprellids were negatively correlated with the level of wave exposure, being more abundant in sheltered (artificial or natural) than in exposed habitats. In this context, Caprella scaura and Paracaprella pusilla, the two introduced caprellids recorded in the Mediterranean, where they are virtually restricted to artificial habitats, may become established in sheltered and even highly polluted natural habitats but hardly colonize wave-exposed rocky shores.

Comparison of the functional responses of invasive and native amphipods

Biology Letters, 2008

While we can usually understand the impacts of invasive species on recipient communities, invasion biology lacks methodologies that are potentially more predictive. Such tools should ideally be straightforward and widely applicable. Here, we explore an approach that compares the functional responses (FRs) of invader and native amphipod crustaceans. Dikerogammarus villosus is a Ponto-Caspian amphipod currently invading Europe and poised to invade North America. Compared with other amphipods that it actively replaces in freshwaters, D. villosus exhibited significantly greater predation, consuming significantly more prey with a higher type II FR. This corroborates the known dramatic field impacts of D. villosus on invaded communities. In another species, FRs were nearly identical in invasive and native ranges. We thus propose that if FRs of other taxa and trophic groups follow such general patterns, this methodology has potential in predicting future invasive species impacts.

Specialization among amphipods: the invasiveGammarus tigrinushas narrower niche space compared to native gammarids

Ecosphere, 2016

Invasions of nonindigenous species (NIS) are considered among the most serious threats to global biodiversity (Costello et al. 2010). When establishing in the recipient ecosystem, NIS may cause significant, unpredictable and irreversible changes to abiotic and biotic environment as well as result in severe economic damage in a variety of waterbodies worldwide (e.g., Carlton 1996, Vitousek et al. 1997, Sala et al. 2000). Despite of their importance, the knowledge on the extent to which NIS actually affect biodiversity and species coexistence is still vague (Gurevitch and Padilla 2004, McGill et al. 2015). Much of ecological theory predicts that species differ in their niches. It has been speculated that sympatric populations of taxonomically closely related species rely on niche separation to reduce competition pressure that, in turn, facilitates long term coexistence (Schoener 1974, Pianka 1978, Fenchel and Kolding 1979, Kolding 1981). The outcome of this niche difference is that species limit their own populations more than they limit others or that niche separation causes intraspecific effects to be more negative than interspecific effects (Chesson 2000). However, there exists an alternative theory that all species are identical in their fitness and in their effects on one another, thus the primary driver of population dynamics

Microhabitat selection by the invasive amphipod Echinogammarus ischnus and native Gammarus fasciatus in laboratory experiments and in Lake Erie

Freshwater Biology, 2003

was the dominant amphipod on rocks covered by Dreissena molluscs compared with those fouled by the filamentous alga Cladophora, while Gammarus fasciatus used both Dreissena and Cladophora substrata extensively. 3. In laboratory habitat selection studies, Echinogammarus chose Dreissena-over Cladophoraencrusted rocks and bare rocks, while Gammarus occupied the more complex substrata equally. 4. Field colonisation experiments demonstrated that the densities of Echinogammarus and Gammarus were positively correlated when the total density of the species was low, in contrast to the large-scale natural distribution of the species that revealed a strong inverse relationship. 5. The ongoing replacement of Gammarus by Echinogammarus in the Laurentian Great Lakes may be related to the stronger affinity of the latter for substrata fouled by Dreissena, a genus with which it co-evolved.

Disentangling ecosystem engineering from short-term biotic effects of a strong invader on a native foundation species

Marine Ecology Progress Series, 2019

Ecosystem engineering effects of dominant species on habitats and consequently on other species are likely to propagate through time at longer distance than the close neighbourhood. Such effects are important to disentangle from short-term biotic effects, especially in biological invasions, as engineering can explain changes in invasion rates over the course of the invasion. We assessed the contribution and spatial dynamics of ecosystem engineering effects of a strong invader, the cordgrass Spartina anglica, on Zostera noltei, a foundation seagrass species of muddy intertidal systems in Europe. Z. noltei transplants were grown at different positions along transects crossing intact S. anglica patches, cut patches and nearby bare sediment on tidal flats in the Bay of Arcachon (France), in order to separate ecosystem engineering effects from short-term biotic effects and evaluate their likely spatial propagation. Bed altimetry, sediment redox potential and granulometry were measured in all treatments. Within Spartina patches, we found strong negative ecosystem engineering effects of the cordgrass on the seagrass associated with increased sediment elevation and relative fine sediment content. Up to 2 m outside the patch, we found significant negative ecosystem engineering effects and positive short-term biotic effects, but they were weak and counterbalanced each other. We conclude that S. anglica can transform a marine muddy intertidal habitat into a drier and more oxidized terrestrial habitat, no longer suitable for the seagrass. Although these effects may propagate at several metres from a patch, they appeared to be too weak to likely affect the seagrass at the scale of a whole bay.

Invasion impacts on functions and services of aquatic ecosystems

Hydrobiologia, 2020

Non-native species can simultaneously affect ecological structures, functions, and services of the invaded ecosystem. In this paper, we report that the study of non-native species impacts on ecosystem function is an emerging topic in aquatic ecology, though studies measuring functions remain relatively uncommon. We hypothesized that study of ecosystem function can reveal emergent effects of non-native species when community structure appears to be unimpacted and the study of multiple functions has the potential to identify impacts masked by foodweb complexity. We compiled information from Web of Science to create a pool of papers (n = 199) addressing ecosystem functions and services that we surveyed to evaluate our hypotheses. The number of publications referencing ecosystem function has increased since 2002, but only 10% of papers measured ecosystem functions as defined in our work. Additionally, 80% of publications reporting functional metrics addressed primary production and nutrient fluxes, while a low number of manuscripts (6%) directly linked the impact of non-native species on ecosystem functions to ecosystem services. We recommend future work focus on less-studied functions (e.g., bioturbation, decay rate, biomagnification), assess multiple functional metrics, link functions to services, and use networks to understand impacts from multiple dimensions of an invaders ecology.

Ecological traits of the amphipod invader Dikerogammarus villosus on a mesohabitat scale

Archiv für Hydrobiologie, 2003

Since 1995, Dikerogammarus villosus Sowinski, a Ponto-Caspian amphipod species, has been invading most of Western Europe's hydrosystems. D. villosus geographic extension and quickly increasing population density has enabled it to become a major component of macrobenthic assemblages in recipient ecosystems. The ecological characteristics of D. villosus on a mesohabitat scale were investigated at a station in the Moselle River. This amphipod is able to colonize a wide range of substratum types, thus posing a threat to all freshwater ecosystems. Rivers whose dominant substratum is cobbles and which have tree roots along the banks could harbour particularly high densities of D. villosus. A relationship exists between substratum particle size and the length of the individuals, and spatial segregation according to length was shown. This allows the species to limit intra-specific competition between generations while facilitating reproduction. A strong association exists between D. villosus and other Ponto-Caspian species, such as Dreissena polymorpha and Corophium curvispinum, in keeping with Invasional Meltdown Theory. Four taxa (Coenagrionidae, Calopteryx splendens, Corophium curvispinum and Gammarus pulex) exhibited spatial niches that overlap significantly that of D. villosus. According to the predatory behaviour of the newcomer, their populations may be severely impacted.

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Effects of coexistence on habitat use and trophic ecology of interacting native and invasive amphipods

Freshwater Biology, 2011

1. Invasive species in aquatic systems are major drivers of changes in biodiversity. Amphipods are key species in freshwaters, with invasive amphipods either replacing or coexisting with native species and often damaging local biodiversity. However, the consequences of interactions among native and invasive amphipods for their habitat use and feeding ecology and ecosystem function are not yet well understood. 2. We examined a number of streams in Brittany and Northern Ireland, with native and invasive amphipods, to evaluate the consequences of species interactions for both habitat use and diet. Our field studies centred on testing two proposed models: a cohabitation model without competition between two native species (Gammarus pulex vs Echinogammarus berilloni), and a competition model between an invasive and a native species (Gammarus pulex vs Gammarus duebeni celticus). For these three species, alone and in combination, we assessed their habitat use and feeding patterns, the latter through gut contents and stable C and N isotope analyses of their tissues. 3. When existing as single-species populations, all three species used stream habitats broadly similarly, although G. pulex was more strongly associated with leaf litter and vegetation compared to pebble substrata than the other species. When G. pulex coexisted with either E. berilloni or G. d. celticus, the latter two changed to using all habitats equally, whereas the former retained its habitat preferences. 4. Similarly, all three species when alone had similar gut contents, with inorganic material predominating, followed by leaf and woody material and more rarely algae and invertebrates. When G. pulex coexisted with E. berilloni, the diet of the latter did not change; however, the frequency of inorganic matter, leaves and wood declined in the gut contents of G. pulex. When G. pulex coexisted with G. d. celticus, the pattern of gut contents did not change in either species. 5. When existing as single-species populations, G. pulex had a broader range of isotopic signatures, both for d 13 C and for d 15 N, than the two other species, indicating a more variable diet among individuals. When G. pulex coexisted with either E. berilloni or G. d. celticus, the latter two had similar ranges of d 13 C and d 15 N, whereas for G. pulex the range was much less for d 13 C and d 15 N, suggesting a less diverse diet. 325 6. Our results infer two different modes of coexistence between native and non-native amphipods. We have shown that the native species, which coexist stably, appear to show interference competition, leading to spatial habitat segregation, whereas competition for food and possible intraguild predation by G. pulex on G. d. celticus would explain why the distribution and density of the latter is affected by G. pulex. However, since all the species have a similar diet and feeding habit, we expect no great overall effect on ecosystem processes as a consequence of species interactions and displacements.

Modified habitats influence an invasive species via direct and indirect effects.

Addition of man-made structures alters abiotic and biotic characteristics of natural habitats, which can influence abundances of biota directly and/or indirectly, by altering the ecology of competitors or predators. Marine epibiota in modified habitats were used to test hypotheses to distinguish between direct and indirect processes. In Sydney Harbour, kelps on pier-pilings supported greater covers of bryozoans, particularly of the non-indigenous species Membranipora membranacea, than found on natural reefs. Pilings influenced these patterns and processes directly due to the provision of shade and indirectly by altering abundances of sea-urchins which, in turn, affected covers of bryozoans. Indirect effects were more important than direct effects. This indicates that artificial structures affect organisms living on secondary substrata in complex ways, altering the biodiversity and indirectly affecting abundances of epibiota. Understanding how these components of habitats affect ecological processes is necessary to allow sensible prediction of the effects of modifying habitats on the ecology of organisms.

Are amphipod invaders a threat to regional biodiversity?

Biological Invasions, 2010

The impact of invasions on local biodiversity is well established, but their impact on regional biodiversity has so far been only sketchily documented. To address this question, we studied the impact at various observation scales (ranging from the microhabitat to the whole catchment) of successive arrivals of non-native amphipods on the amphipod assemblage of the Loire River basin in France. Amphipod assemblages were studied at 225 sites covering the whole Loire catchment. Non-native species were dominant at all sites in the main channel of the Loire River, but native species were still present at most of the sites. We found that the invaders have failed to colonize most of tributaries of the Loire River. At the regional scale, we found that since the invaders first arrived 25 years ago, the global amphipod diversity has increased by 33% (from 8 to 12 species) due to the arrival of non-native species. We discuss the possibility that the lack of any loss of biodiversity may be directly linked to the presence of refuges at the microhabitat scale in the Loire channel and in the tributaries, which invasive species have been unable to colonize. The restoration of river quality could increase the number of refuges for native species, thus reducing the impact of invaders.

When does ecosystem engineering cause invasion and species replacement?

Oikos, 2008

Introduced exotic species can dominate communities and replace native species that should be better adapted to their local environment, a paradox that is usually explained by the absence of natural enemies and by habitat alteration resulting from anthropogenic disturbance. Additionally, introduced species can enhance their invasion success and impact on native species by modifying selection pressures in their new environment through ecosystem engineering. We analyse a simple dynamic model of indirect competition for habitat between a non-engineering resident species and an engineering exotic species. The conditions for invasion and competitive exclusion of the resident by the exotic species and the range of dynamic outcomes suggested by the model are determined by the form of density dependence. We give simple criteria for the success of the invading species on dimensionless quantities involving rates of ecosystem engineering and of habitat degradation. The model's predictions offer an additional explanation for a range of invasion dynamics reported in the literature, including lag times between introduction and establishment. One intriguing result is that a series of failed invasions may successively reduce environmental resistance to subsequent invasion, through a cumulative effect of habitat transformation. More work is needed to determine the frequency and conditions in which engineering is required for successful establishment, and whether highly-successful (or high-impact) invaders are more likely to possess ecosystem engineering traits.

Modified habitats change ecological processes affecting a non-indigenous epibiont.

Urbanisation of coastal habitats, particularly the increased numbers of pier-pilings, jetties and seawalls along shorelines, affects natural systems. Epibiota on secondary substrata (kelps, Ecklonia radiata) in man-made structures differ from those in natural habitats, but they have received considerably less attention. To understand the consequences of changes in the structure of these assemblages, it is therefore necessary to determine which ecological processes are being affected and the factors influencing them. In Sydney Harbour, kelps on pier-pilings supported greater covers of bryozoans, particularly of the non-indigenous species Membranipora membranacea, than found on natural reefs. Experimental transplants of kelps without epibiota from reefs to pilings showed that recruitment and growth of colonies of M. membranacea were much greater on pilings than on reefs. Patterns of distribution and abundance of this epibiotic bryozoan are determined by a combination of these processes and probably influenced by differences in abiotic and biotic characteristics between habitats. Understanding how these components of habitats affect ecological processes is necessary to allow sensible prediction of the effects of modifying habitats on the ecology of organisms.

Differential ecological impacts of invader and native predatory freshwater amphipods under environmental change are revealed by comparative functional responses

Predicting the ecological impacts of dam- aging invasive species under relevant environmental contexts is a major challenge, for which comparative functional responses (the relationship between resource availability and consumer uptake rate) have great potential. Here, the functional responses of Gammarus pulex,an ecologically damaging invader in freshwaters in Ireland and other islands, were com- pared with those of a native trophic equivalent Gammarus duebeni celticus. Experiments were con- ducted at two dissolved oxygen concentrations (80 and 50 % saturation), representative of anthropogenic water quality changes, using two larval prey, blackfly (Simuliidae spp.) and mayfly (Baetis rhodani). Over- all, G. pulex had higher Type II functional responses and hence predatory impacts than G. d. celticus and the functional responses of both predators were reduced by lowered oxygen concentration. However, this reduction was of lower magnitude for the invader as compared to the native. Further, the invader functional response at low oxygen was comparable to that of the native at high oxygen. Attack rates of the two predators were similar, with low oxygen reducing these attack rates, but this effect occurred more strongly for blackfly than mayfly prey. Handling times were significantly lower for the invader compared with the native, and significantly higher at low oxygen, however, the effect of lowered oxygen on handling times was minimal for the invader and pronounced for the native. Maximum feeding rates were significantly greater for the invader compared with the native, and significantly reduced at low oxygen, with this effect again lesser for the invader as compared to the native. The greater functional responses of the invader corroborate with its impacts on recipient macroinver- tebrate communities when it replaces the native. Further, our experiments predict that the impact of the invader will be less affected than the native under altered oxygen regimes driven by anthropogenic influences.

Invader abundance and contraction of niche breadth during replacement of a native gammarid amphipod

Ecology and Evolution, 2022

The introduction of non-native species to new locations is a growing global phenomenon with major negative effects on native species and biodiversity. Such introductions potentially bring competitors into contact leading to partial or total species replacements. This creates an opportunity to study novel species interactions as they occur, with the potential to address the strength of inter-and intraspecific interactions, most notably competition. Such potential has often not been realized, however, due to the difficulties inherent in detecting rapid and spatially expansive species interactions under natural field conditions. The invasive amphipod crustacean Gammarus pulex has replaced a native species, Gammarus duebeni celticus, in river and lake systems across Europe. This replacement process is at least partially driven by differential parasitism, cannibalism, and intraguild predation, but the role of interspecific competition has yet to be resolved. Here, we examine how abundance of an invasive species may affect spatial niche breadth of a native congeneric species. We base our analyses of niche breadth on ordination and factor analysis of biological community and physical parameters, respectively, constituting a summative, multidimensional approach to niche breadth along environmental gradients. Results derived from biological and environmental niche criteria were consistent, although interspecific effects were stronger using the biological niche approach. We show that the niche breadth of the native species is constrained as abundance of the invader increases, but the converse effect does not occur. We conclude that the interaction between invasive G. pulex and native G. d. celticus under natural conditions is consistent with strong interspecific competition whereby a native, weaker competitor is replaced by a superior invasive competitor. This study indicates a strong role of interspecific competition, alongside other known interactions such as differential intraguild predation, in rapid and expansive species replacements following biological invasions.