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David M Lodge - One of the best experts on this subject based on the ideXlab platform.
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environmental dna edna detects the invasive Crayfishes orconectes rusticus and pacifastacus leniusculus in large lakes of north america
Hydrobiologia, 2017Co-Authors: Eric Larson, David M Lodge, Mark A Renshaw, Crysta A Gantz, John Umek, Sudeep Chandra, Scott P EganAbstract:We report results of a study that made reciprocal comparisons of environmental DNA (eDNA) assays for two major invasive Crayfishes between their disparate invasive ranges in North America. Specifically, we tested for range expansions of the signal Crayfish Pacifastacus leniusculus (Dana, 1852) into the Laurentian Great Lakes region known to be invaded by the Rusty Crayfish Orconectes rusticus (Girard, 1852), as well as for the invasion of O. rusticus into large lakes of California and Nevada, US known to be invaded by P. leniusculus. We compared eDNA detections to historic localities for O. rusticus within the Great Lakes, and to recent sampling for presence/absence and relative abundance of P. leniusculus in California and Nevada via overnight sets of baited traps. We successfully detected O. rusticus eDNA at six sites from the Great Lakes and P. leniusculus from six of seven lakes where it was known to occur in California and Nevada, but did not detect any range expansions by either species across the North American continent. eDNA appears suitable to detect benthic arthropods from exceptionally large lakes, and will likely be useful in applications for monitoring of new biological invasions into these and other freshwater and marine habitats.
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environmental dna edna detects the invasive Rusty Crayfish orconectes rusticus at low abundances
Journal of Applied Ecology, 2016Co-Authors: Eric Larson, Matthew M Dougherty, Mark A Renshaw, Crysta A Gantz, Scott P Egan, Daniel M Erickson, David M LodgeAbstract:Early detection is invaluable for the cost-effective control and eradication of invasive species, yet many traditional sampling techniques are ineffective at the low population abundances found at the onset of the invasion process. Environmental DNA (eDNA) is a promising and sensitive tool for early detection of some invasive species, but its efficacy has not yet been evaluated for many taxonomic groups and habitat types.We evaluated the ability of eDNA to detect the invasive Rusty Crayfish Orconectes rusticus and to reflect patterns of its relative abundance, in upper Midwest, USA, inland lakes. We paired conventional baited trapping as a measure of Crayfish relative abundance with water samples for eDNA, which were analysed in the laboratory with a qPCR assay. We modelled detection probability for O. rusticus eDNA using relative abundance and site characteristics as covariates and also tested the relationship between eDNA copy number and O. rusticus relative abundance.We detected O. rusticus eDNA in all lakes where this species was collected by trapping, down to low relative abundances, as well as in two lakes where trap catch was zero. Detection probability of O. rusticus eDNA was well predicted by relative abundance of this species and lake water clarity. However, there was poor correspondence between eDNA copy number and O. rusticus relative abundance estimated by trap catches. Synthesis and applications. Our study demonstrates a field and laboratory protocol for eDNA monitoring of Crayfish invasions, with results of statistical models that provide guidance of sampling effort and detection probabilities for researchers in other regions and systems. We propose eDNA be included as a tool in surveillance for invasive or imperilled Crayfishes and other benthic arthropods.
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do invasive Rusty Crayfish orconectes rusticus decouple littoral and pelagic energy flows in lake food webs
Freshwater Science, 2016Co-Authors: Eric Larson, Timothy A Kreps, David M LodgeAbstract:AbstractLinkages between habitats can strongly affect ecosystem function through exchange of energy and materials. In lake food webs, large piscivorous fishes integrate littoral and pelagic energy sources through the consumption of smaller fishes and macroinvertebrates. We tested the hypothesis that the introduction of the invasive Rusty Crayfish (Orconectes rusticus) decouples littoral and pelagic food webs by reducing the abundance of small fish and nonCrayfish benthic macroinvertebrates, thereby shifting diets of large fish to increased dependence on littoral energy sources (i.e., Crayfish). We used stable isotope ratios of C (δ13C) and N (δ15N) to examine differences in resource use between lakes with high abundance of O. rusticus (invaded) and lakes with native Crayfish only or with low abundance of nonnative Crayfish (uninvaded). The trophic position of juvenile Crayfish was lower in invaded than in uninvaded lakes, results suggesting decreased availability of, and reliance on, macroinvertebrate pre...
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evolution of invasive traits in nonindigenous species increased survival and faster growth in invasive populations of Rusty Crayfish orconectes rusticus
Evolutionary Applications, 2014Co-Authors: Lindsey W Sargent, David M LodgeAbstract:The importance of evolution in enhancing the invasiveness of species is not well understood, especially in animals. To evaluate evolution in Crayfish invasions, we tested for differences in growth rate, survival, and response to predators between native and invaded range populations of Rusty Crayfish (Orconectes rusticus). We hypothesized that low conspecific densities during introductions into lakes would select for increased investment in growth and reproduction in invasive populations. We reared Crayfish from both ranges in common garden experiments in lakes and mesocosms, the latter in which we also included treatments of predatory fish presence and food quality. In both lake and mesocosm experiments, O. rusticus from invasive populations had significantly faster growth rates and higher survival than individuals from the native range, especially in mesocosms where fish were present. There was no influence of within-range collection location on growth rate. Egg size was similar between ranges and did not affect Crayfish growth. Our results, therefore, suggest that growth rate, which previous work has shown contributes to strong community-level impacts of this invasive species, has diverged since O. rusticus was introduced to the invaded range. This result highlights the need to consider evolutionary dynamics in invasive species mitigation strategies.
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a trematode parasite alters growth feeding behavior and demographic success of invasive Rusty Crayfish orconectes rusticus
Oecologia, 2014Co-Authors: Lindsey W Sargent, Ashley K Baldridge, Maraliz Vegaross, Kevin Towle, David M LodgeAbstract:Nonindigenous species can cause major changes to community interactions and ecosystem processes. The strong impacts of these species are often attributed to their high demographic success. While the importance of enemy release in facilitating invasions has often been emphasized, few studies have addressed the role of parasites in the invasive range in controlling demographic success of potential invaders. Here we examine whether a trematode parasite (Microphallus spp.) can contribute to previously documented alternate states in the abundance of invasive Rusty Crayfish (Orconectes rusticus) in north temperate lakes in Wisconsin, USA. Microphallus infect O. rusticus after emerging from their first intermediate host, a hydrobiid snail. As previously documented, O. rusticus reduce densities of hydrobiid snails through direct predation and destruction of macrophyte habitat. Therefore, if Microphallus substantially reduce O. rusticus fitness, these parasites may reinforce a state of low Crayfish abundance, and, at the other extreme, abundant Crayfish may repress these parasites, reinforcing a state of high Crayfish abundance. From samples collected from 109 sites in 16 lakes, we discovered (1) a positive relationship between Crayfish infection intensity and hydrobiid snail abundance, (2) a negative relationship between parasite prevalence and Crayfish abundance, and (3) a negative relationship between parasite prevalence and Crayfish population growth. With experiments, we found that infection with Microphallus reduced foraging behavior and growth in O. rusticus, which may be the mechanisms responsible for the population reductions we observed. Overall results are consistent with the hypothesis that Microphallus contributes to alternate states in the abundance and impacts of O. rusticus.
Julian D. Olden - One of the best experts on this subject based on the ideXlab platform.
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phenotypic variability of Rusty Crayfish faxonius rusticus at the leading edge of its riverine invasion
Freshwater Biology, 2019Co-Authors: Mathis L Messager, Julian D. OldenAbstract:Species around the globe are undergoing phenotypic shifts at ecologically relevant timescales as they invade new ecosystems and respond to changing environments. Disentangling the contribution of environmental gradients from the process of range expansion in shaping these changes, and identifying the specific traits undergoing selection, are both critical to anticipate the secondary spread and impact of invasive species. Here, we investigate phenotypic changes in Rusty Crayfish (Faxonius rusticus), a nuisance invasive species, through an extensive survey of their invasion gradient in multiple tributaries of the John Day River (JDR, Oregon, U.S.A.), a major tributary of the Columbia River. Rusty Crayfish in the JDR have developed better physiological condition (intrinsic growth and/or reproductive potential measured as RNA/DNA ratio) but less competitive morphology (lighter body and smaller claws) as they spread upstream and downstream from their location of initial introduction. In addition, Rusty Crayfish in invasion front populations are at a lower trophic level than conspecifics closer to core areas. By accounting for variations in temperature, primary productivity, and prey (macroinvertebrates) biomass throughout the invasion extent of Rusty Crayfish, our findings suggest that low conspecific densities at the invasion edge and spatial sorting primarily drive these phenotypic changes. The trends observed here are thus likely to intensify over time as Rusty Crayfish continues to rapidly spread throughout the JDR and reach the mainstem Columbia River. Our study shows that phenotypic shifts can manifest rapidly over environmental gradients experienced during the range expansion of aquatic invasive species. Patterns in both morphological and functional traits documented in the JDR demonstrate the importance of both environmental factors and dispersal processes in shaping these responses in riverine networks.
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assessing ecosystem vulnerability to invasive Rusty Crayfish orconectes rusticus
Ecological Applications, 2011Co-Authors: Julian D. Olden, Jake Vander M Zanden, Pieter T J JohnsonAbstract:Despite the widespread introduction of nonnative species and the heterogeneity of ecosystems in their sensitivity to ecological impacts, few studies have assessed ecosystem vulnerability to the entire invasion process, from arrival to establishment and impacts. Our study addresses this challenge by presenting a probabilistic, spatially explicit approach to predicting ecosystem vulnerability to species invasions. Using the freshwater-rich landscapes of Wisconsin, USA, we model invasive Rusty Crayfish (Orconectes rusticus) as a function of exposure risk (i.e., likelihood of introduction and establishment of O. rusticus based on a species distribution model) and the sensitivity of the recipient community (i.e., likelihood of impacts on native O. virilis and O. propinquus based on a retrospective analysis of population changes). Artificial neural networks predicted that approximately 10% of 4200 surveyed lakes (n = 388) and approximately 25% of mapped streams (23 523 km total length) are suitable for O. rusticus introduction and establishment. A comparison of repeated surveys before vs. post-1985 revealed that O. virilis was six times as likely and O. propinquus was twice as likely to be extirpated in streams invaded by O. rusticus, compared to streams that were not invaded. Similarly, O. virilis was extirpated in over three-quarters of lakes invaded by O. rusticus compared to half of the uninvaded lakes, whereas no difference was observed for O. propinquus. We identified 115 lakes (approximately 3% of lakes) and approximately 5000 km of streams (approximately 6% of streams) with a 25% chance of introduction, establishment, and extirpation by O. rusticus of either native congener. By identifying highly vulnerable ecosystems, our study offers an effective strategy for prioritizing on-the-ground management action and informing decisions about the most efficient allocation of resources. Moreover, our results provide the flexibility for stakeholders to identify priority sites for prevention efforts given a maximum level of acceptable risk or based on budgetary or time restrictions. To this end, we incorporate the model predictions into a new online mapping tool with the intention of closing the communication gap between academic research and stakeholders that requires information on the prospects of future invasions.
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behavioural and growth differences between experienced and naive populations of a native Crayfish in the presence of invasive Rusty Crayfish
Freshwater Biology, 2009Co-Authors: Nicole M Hayes, Julian D. Olden, Katrina J Butkas, Jake Vander M ZandenAbstract:Summary 1. Species invasions are a leading threat to native species and ecosystems. How populations of native species respond to the presence of invasive species will ultimately determine their long-term persistence. 2. In this study, we capitalise on a unique opportunity to compare the behaviour and growth of naive and experienced virile Crayfish (Orconectes virilis Hagen) populations in the presence of invasive Rusty Crayfish (O. rusticus Girard). In behavioural trials, experienced O. virilis (coexisted with O. rusticus for >30 years) showed more aggressive behaviour than their naive counterparts. Naive O. virilis retreated from aggressive interactions with O. rusticus 38% more often than experienced O. virilis. Experienced O. virilis spent 39% more time occupying shelter than naive O. virilis. 3. There were also differences in O. rusticus behaviour: O. rusticus spent 24% more time occupying shelter with naive O. virilis relative to experienced O. virilis. 4. In field mesocosm experiments with O. rusticus, naive O. virilis declined in body mass by 1% while experienced O. virilis’ body mass increased by 6%, thus highlighting the potential population-level implications of the previously observed behavioural effects. 5. Our work demonstrates significant behaviour and growth differences between naive and experienced O. virilis in the presence of invasive O. rusticus. Whether this difference is the result of phenotypic plasticity or evolution by natural selection remains to be determined. Either way, this area of inquiry has implications for managing native populations and species in an increasingly invaded world.
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interactions among invaders community and ecosystem effects of multiple invasive species in an experimental aquatic system
Oecologia, 2009Co-Authors: Pieter T J Johnson, Julian D. Olden, Christopher T Solomon, Jake Vander M ZandenAbstract:With ecosystems increasingly supporting multiple invasive species, interactions among invaders could magnify or ameliorate the undesired consequences for native communities and ecosystems. We evaluated the individual and combined effects of Rusty Crayfish (Orconectes rusticus) and Chinese mystery snails [Bellamya (=Cipangopaludina) chinensis] on native snail communities (Physa, Helisoma and Lymnaea sp.) and ecosystem attributes (algal chlorophyll a and nutrient concentrations). Both invaders are widespread in the USA and commonly co-occur within northern temperate lakes, underscoring the importance of understanding their singular and joint effects. An outdoor mesocosm experiment revealed that while the two invaders had only weakly negative effects upon one another, both negatively affected the abundance and biomass of native snails, and their combined presence drove one native species to extinction and reduced a second by >95%. Owing to its larger size and thicker shell, adult Bellamya were protected from Crayfish attack relative to native species (especially Physa and Lymnaea), suggesting the co-occurrence of these invaders in nature could have elevated consequences for native communities. The per capita impacts of Orconectes (a snail predator) on native snails were substantially greater than those of Bellamya (a snail competitor). Crayfish predation also had a cascading effect by reducing native snail biomass, leading to increased periphyton growth. Bellamya, in contrast, reduced periphyton biomass, likely causing a reduction in growth by native lymnaeid snails. Bellamya also increased water column N:P ratio, possibly because of a low P excretion rate relative to native snail species. Together, these findings highlight the importance of understanding interactions among invasive species, which can have significant community- and ecosystem-level effects.
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first record of orconectes rusticus girard 1852 decapoda cambaridae west of the great continental divide in north america
Crustaceana, 2009Co-Authors: Julian D. Olden, Jeffrey W Adams, Eric LarsonAbstract:Orconectes rusticus (Girard, 1852), known as the Rusty Crayfish, have spread over the last 50 years from their historical range in the Ohio River drainage, United States, to waters throughout much of 18 additional eastern and central states, provinces of Ontario and Qu?bec in Canada, and the Laurentian Great Lakes (Hobbs et al., 1989; Olden et al., 2006; Taylor et al., 2007). O. rusticus are omni vores and aggressive, resulting in numerous ecological and evolutionary impacts manifested across entire food webs. The invasion of this species has been associ ated with negative effects on aquatic plants, invertebrates, snails, and fishes (e.g., Olsen et al., 1991; Lodge et al., 1994; McCarthy et al., 2006), in addition to dis placing and hybridizing with native Crayfish (e.g., Perry et al., 2001). The most westward reported occurrences of O. rusticus are the North Platte River near Dou glas, Wyoming (where the population is believed to have been successfully eradi cated) and Conchas Lake in north-east New Mexico (Bouchard, 1977). Preventing the westward spread of aquatic nuisance species from eastern North America is a primary goal of the 100th Meridian Initiative (http://www.100thmeridian.org). Here we are the first to document the presence of O. rusticus west of the Continental Divide in North America, separating watersheds that drain into the Pacific Ocean from those river systems that drain into the Atlantic Ocean. On 19 July 2005, a field survey conducted by the Xerces Society for Invertebrate Conservation and the Confederated Tribes of Warm Springs Reservation of Oregon revealed the occurrence of a non-native Orconectes sp. Crayfish in the upper
William Perry - One of the best experts on this subject based on the ideXlab platform.
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invasive Rusty Crayfish faxonius rusticus populations in north america are infected with the Crayfish plague disease agent aphanomyces astaci
Freshwater Science, 2019Co-Authors: Jorn Panteleit, William Perry, Thomas G Horvath, Japo Jussila, Jenny Makkonen, Ralf Schulz, Kathrin Theissinger, Anne SchrimpfAbstract:AbstractThe American Rusty Crayfish, Faxonius rusticus, is an invasive species in parts of North America where it displaces native Crayfish species. In Europe, various invasive North American crayf...
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increased salinity affects survival and osmotic response of Rusty Crayfish orconectes rusticus girard 1852 and northern clearwater Crayfish o propinquus girard 1852 decapoda astacoidea cambaridae as salinity increases the potential for estuarine inva
Journal of Crustacean Biology, 2016Co-Authors: Caisie E Bazer, Robert L Preston, William PerryAbstract:The potential colonization of the Rusty Crayfish, Orconectes rusticus (Girard, 1852), has previously focused on lakes and streams of northeastern United States and southeastern Canada, but estuaries have not been considered. Rusty Crayfish have recently been reported in tributaries of the Chesapeake Bay and the potential exists for Crayfishes to invade and spread into the estuary. We determined survival, hemolymph osmotic pressure, and identified possible mechanisms of osmoregulation of the invasive O. rusticus and northern clearwater Crayfish, Orconectes propinquus (Girard, 1852), in salinities of 0.5, 5, 15, and 30 ppt. Survival of both Crayfishes (>83%) was unaffected at salinities of up to 15 ppt but declined significantly at 30 ppt to 17% for O. rusticus ( P O. propinquus ( P > 0 . 05 ). Hemolymph osmotic pressure in both species was higher than the external medium up to 15 ppt, and then became nearly isosmotic with salinities at 30 ppt with a significant species by treatment interaction ( F 3 , 55 = 4 . 4627 , P = 0 . 0071 ). The primary osmoregulatory mechanisms in Crayfishes involve ions (Na + and Cl − ) and free amino acids (FAAs) in muscle tissues. Concentrations of Na + and Cl − increased with increasing salinity in both species and accounted for 74-91% of the total hemolymph osmotic pressure with a significant species (Pillai’s Trace = 0.9565, P 0 . 05 ). FAA in tail muscle tissue increased significantly with increasing salinity with a significant species by treatment interaction ( F 3 , 20 = 5 . 1911 , P = 0 . 0082 ). Both O. rusticus and O. propinquus were active in salinities of up to 15 ppt and were able to osmoregulate. Based on these laboratory experiments, the potential exists for both of these species to spread through large areas of estuaries into new rivers potentially threatening previously isolated watersheds.
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the role of hybridization in a species invasion and extirpation of resident fauna hybrid vigor and breakdown in the Rusty Crayfish orconectes rusticus
Journal of Crustacean Biology, 2014Co-Authors: Tracy Arcella, David M Lodge, William Perry, Jeffrey L FederAbstract:The Rusty Crayfish, Orconectes rusticus (Girard, 1852), is native to the Ohio River basin, but was introduced into northern Midwestern lakes through the bait trade about 50 years ago. Since then, the Rusty Crayfish has spread rapidly through lakes in northern Wisconsin, displacing two resident species of Crayfish, O. propinquus (Girard, 1852), the northern clearwater Crayfish, and O. virilis (Hagen, 1870), the virile Crayfish. Previous studies have shown that as O. rusticus invades, it hybridizes extensively with O. propinquus, but not with O. virilis. Here, we examine why stable hybrid zones do not form between O. rusticus and O. propinquus, but instead hybridization accelerates the decline of O. propinquus. We report that although putative F1 hybrids tend to grow faster and survive better than other Crayfish, backcross hybrid Crayfish tend to have fewer young (at a given age) that grow more slowly and experience lower survivorship than F1 hybrids and both parental species. Parental O. rusticus, in comparison, have offspring numbers and growth rates more similar to those of F1 hybrids, while survivorship is intermediate between F1 hybrids and backcrosses. Consequently, hybrid breakdown appears to occur in latter generation Crayfish of mixed ancestry, resulting in unstable hybrid zones in lakes that speed the extirpation of O. propinquus. Our findings underscore the negative effects that hybridization can have on conserving native gene pools, a danger that may be particularly detrimental for the great diversity of North American Crayfishes.
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effects of water velocity on the size and shape of Rusty Crayfish orconectes rusticus
Freshwater Science, 2013Co-Authors: William Perry, Anthony M Jacks, Daniel Fiorenza, Madeleine Young, Richard Kuhnke, Stephen J JacqueminAbstract:AbstractPhenotypic plasticity of ecologically relevant traits relating to physiology, behavior, morphology, and life history is widespread and can affect the ecology and evolution of organisms. In streams, phenotypic plasticity in morphology and corresponding differences in performance have been documented for fishes and, to a lesser extent, for macroinvertebrates. Morphological plasticity in Crayfish has not been addressed but, if present, has the potential to interact with behaviorally plastic traits to affect performance in high water velocities. Lake and stream invasions of Rusty Crayfish, Orconectes rusticus, provide excellent opportunities to examine morphological variation in habitats differing in water velocity. Spread of O. rusticus and displacement of resident species in lakes has been attributed to larger mean body and chelae sizes than for native species, but larger body and chelae sizes may not be advantageous in high-velocity environments. We examined populations of male O. rusticus (form I ...
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laboratory competition hierarchies between potentially invasive Rusty Crayfish orconectes rusticus and native Crayfishes of conservation concern
American Midland Naturalist, 2013Co-Authors: Karen Szela, William PerryAbstract:Abstract Introduced Crayfishes represent a serious threat to the endangered aquatic fauna of North America and Europe. We used small-scale competition assay experiments to examine competitive hierarchies in the laboratory between male and female Orconectes rusticus and Orconectes illinoiensis, Orconectes indianensis, and Orconectes placidus from southern Illinois. These species are considered threatened in Illinois and there is a potential for O. rusticus to become established in drainages inhabited by these species. Using sex and size-matched laboratory competition trials for a limited food resource, we found that both male and female O. rusticus were competitively dominant to O. placidus, O. illinoiensis and O. indianensis (P 0.05). Female O. placidus were, however, competitively dominant to O. illinoiensis which was dominant to O. indianensis (P < 0.05). These simple laboratory competition experimen...
Brian M Roth - One of the best experts on this subject based on the ideXlab platform.
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changes in the distribution of michigan Crayfishes and the influence of invasive Rusty Crayfish faxonius rusticus on native Crayfish substrate associations
Biological Invasions, 2019Co-Authors: Kelley R Smith, Brian M Roth, Michael L Jones, Daniel B Hayes, Seth J Herbst, Nicholas PopoffAbstract:Invasive Crayfishes have a strong negative effect on multiple trophic levels, including other Crayfishes. However, documentation of the spread of non-native Crayfish species and their impact on native Crayfishes could be improved, particularly over large spatial scales in stream ecosystems. We collected Crayfish and quantified habitat at 461 stream sites throughout Michigan in 2014–2016 and compared our collections to a historical account of Crayfish collections published in 1975. Our objectives were to: (1) quantify the change in non-native Rusty Crayfish (Faxonius rusticus) and native species distributions from 1975 to 2014–2016; (2) quantify how Rusty Crayfish affect the habitat associations of native species in Michigan streams; and (3) determine the effectiveness of dipnets, our primary sampling method. We found all species in more watersheds compared to 1975, likely due in part to increased sampling. However, we found Rusty Crayfish in 22 more HUC-8 watersheds than in 1975, a larger increase than all other species. Habitat associations of native species also shift in the presence of Rusty Crayfish. In instances where native species co-occurred with Rusty Crayfish, most obligate aquatic native species were found in less-preferred habitat such as sand or macrophytes compared to cobble substrate when the species is in isolation. Our results indicate a broad range expansion by Rusty Crayfish over the last 40 years, suggesting that surveys of Crayfish diversity and habitat occupancy should be more routine to inform management of native Crayfish species.
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reciprocal relationships between exotic Rusty Crayfish macrophytes and lepomis species in northern wisconsin lakes
Ecosystems, 2007Co-Authors: Brian M Roth, Jakob C Tetzlaff, Mara L Alexander, James F KitchellAbstract:The non-native Rusty Crayfish (Orconectes rusticus) has invaded many lakes of northern Wisconsin, profoundly changing littoral zones in the process. There are other lakes that have been invaded, but do not exhibit these changes. We hypothesized that endogenous feedbacks could form involving Rusty Crayfish, the macrophytes they destroy, and Lepomis species whose abundance is positively related to macrophyte abundance and also consume juvenile Crayfish. We assessed this proposal with long-term data from one lake, a regional comparative study, and a case study of Lepomis predation on Crayfish. Through time and across lakes, abundances of Rusty Crayfish, littoral macrophytes and species of the genus Lepomis were related in a fashion that indicated a set of feedbacks that regulate the abundance of all three. Intense predation on juvenile Crayfish by abundant Lepomis is capable of maintaining some Crayfish populations at low abundance. Thus, some lakes display profound ecological changes where Crayfish achieve high abundance, and others sustain Crayfish at low abundance. Consequently, lakes invaded by Rusty Crayfish may take on the appearance of alternative ecological regimes. Direct experimentation is necessary to determine if, and under what conditions, a lake can exist in either regime.
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fish predation and trapping for Rusty Crayfish orconectes rusticus control a whole lake experiment
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Catherine L Hein, Brian M Roth, Anthony R Ives, Jake Vander M ZandenAbstract:Improved methods are needed for the prevention and control of invasive species. We investigated the potential to control a Rusty Crayfish (Orconectes rusticus) population in an isolated lake in northern Wisconsin by trapping adult Crayfish and restricting fishing, thereby increasing fish populations and predation on small Crayfish. Over a 3 year period, traps and predatory fishes removed substantial portions of the Rusty Crayfish population. We used an age-structured population model to determine which removal method had the largest effect on Crayfish population growth rates. Because more Crayfish were vulnerable to and removed by fish predation than by trapping, fish predation caused a larger decline in the population growth rate. However, trapping removed Crayfish with the highest reproductive value and caused the largest decline in population growth rate per individual Crayfish removed. Consideration of density-dependent responses to removal is necessary to predict long-term effects on Rusty Crayfish p...
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using bioenergetics and stable isotopes to assess the trophic role of Rusty Crayfish orconectes rusticus in lake littoral zones
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Brian M Roth, Catherine L Hein, Jake Vander M ZandenAbstract:Crayfish often dominate freshwater ecosystems and can have strong effects on littoral habitat and biota through foraging. However, there is substantial debate regarding the trophic role of Crayfish and implications of their foraging behavior on littoral ecosystems. We created a bioenergetics model for Rusty Crayfish (Orconectes rusticus )t o determine how growth and prey choice constrain Crayfish consumption, which affects littoral ecosystems. We simulated over 6400 potential Rusty Crayfish diets by varying the abundance of important prey. We judged how Crayfish prey choice affects the amount and identity of prey that Crayfish must consume to match observed growth. We compared our model predictions with stable isotope evidence from 10 northern Wisconsin lakes to determine energy sources and trophic position of Rusty Crayfish relative to other invertebrates. Our diet simulations and stable isotope analysis con- curred that Crayfish of all ages are primarily predators. Individuals that do not feed on zoobenthos must therefore con- sume large quantities of less desirable food such as macrophytes, which are an important component of littoral habitat. Resume : Les ecrevisses dominent souvent les ecosystemes d'eau douce et peuvent, par leur recherche de nourriture, avoir de profonds effets sur l'habitat littoral et les organismes qui y vivent. Cependant, il existe un important debat sur le role trophique des ecrevisses et les consequences de leur comportent de recherche de nourriture sur les ecosystemes littoraux. Nous avons mis au point un modele bioenergetique pour l'ecrevisse americaine (Orconectes rusticus )a fin de determiner comment la croissance et le choix des proies limitent la consommation des ecrevisses, ce qui affecte les ecosystemes littoraux. Nous avons fait des simulations impliquant plus de 6400 regimes alimentaires potentiels d'ecrevisses en faisant varier l'abondance des proies principales. Nous avons determine comment le choix des proies par les ecrevisses affecte le nombre et l'identite des proies que l'ecrevisse doit consommer pour expliquer la croissance observee. Nous avons compare les predictions de notre modele et les donnees d'analyse des isotopes stables provenant de 10 lacs du nord du Wisconsin afin de determiner les sources d'energie et la position trophique de l'ecrevisse americaine par rapport aux autres invertebres. Nos simulations de regimes alimentaires et l'analyse des isotopes stables s'accordent pour trouver que les ecrevisses de tous les âges sont principalement des predateurs. Les individus qui ne se nourrissent pas de zoobenthos doivent consommer de grandes quantites de nourriture moins desirable, telle que les macrophytes qui forment un compartiment relativement important de l'habitat littoral. (Traduit par la Redaction)
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the role of size selective predation in the displacement of orconectes Crayfishes following Rusty Crayfish invasion
Crustaceana, 2005Co-Authors: Brian M Roth, James F KitchellAbstract:[Selective predation can drive community composition. We designed a field study to determine if selective predation by fishes accounts for population dominance of the exotic Rusty Crayfish, Orconectes rusticus , in a northern Wisconsin lake. We hypothesized that fish predators avoid consuming O. rusticus in favor of congeners O. propinquus and O. virilis because O. rusticus attains either superior size or is more aggressive than its congeners. Largely based on previous experimental work, we expected that predators would consume smaller individuals of Rusty Crayfish than of other species, as a result of behavioral differences among Crayfish species. Although smallmouth bass ( Micropterus dolomieu ) and yellow perch ( Perca flavescens ) consumed fewer Rusty Crayfish than expected based on relative prey abundance, predators consumed similar sized Crayfish of all species. Further, our results indicated that predators likely avoid O. rusticus because they have larger chelae than congeners, and that behavioral differences did not appear to contribute substantially to Crayfish selection at the whole lake scale. Our results suggest that selective predation based on chelae size is one of the primary drivers of this species replacement. Selective predation commonly accelerates exotic dominance over native prey and should be considered explicitly in exotic species investigations. La predation selective peut determiner la composition d'une communaute. Nous avons organise une etude de terrain pour determiner si la predation selective par les poissons explique la dominance de la population d'ecrevisse rustique, Orconectes rusticus , dans un lac du nord du Wisconsin. L'hypothese initiale etait que les poissons predateurs evitent de consommer O. rusticus plutot que ses congeneres O. propinquus et O. virilis parce que O. rusticus , soit atteint une taille superieure, soit est plus agressive que ses congeneres. Sur la base d'un travail experimental precedent, nous avons suppose que les predateurs consommeraient des individus de l'ecrevisse rustique petits plutot que ceux d'autres especes en raison des differences de comportement entre les especes d'ecrevisses. Bien que le blackbass a petite bouche ( Micropterus dolomieu ) et la perche jaune ( Perca flavescens ) aient consomme moins d'ecrevisses rustiques que prevu en considerant l'abondance relative des proies, les predateurs ont consomme les ecrevisses de meme taille des differentes especes. De plus, nos resultats ont indique que les predateurs evitent probablement O. rusticus parce qu'elles ont des pinces plus grandes que leurs congeneres et que les differences de comportement ne semblent pas contribuer substantiellement a la selection des ecrevisses a l'echelle du lac etudie. Nos resultats suggerent que la predation selective fondee sur la taille des pinces est le principal facteur du remplacement des especes. La predation selective accelere habituellement la dominance des especes exotiques par rapport aux especes indigenes et devrait etre davantage prise en compte dans les investigations sur les especes exotiques. , Selective predation can drive community composition. We designed a field study to determine if selective predation by fishes accounts for population dominance of the exotic Rusty Crayfish, Orconectes rusticus , in a northern Wisconsin lake. We hypothesized that fish predators avoid consuming O. rusticus in favor of congeners O. propinquus and O. virilis because O. rusticus attains either superior size or is more aggressive than its congeners. Largely based on previous experimental work, we expected that predators would consume smaller individuals of Rusty Crayfish than of other species, as a result of behavioral differences among Crayfish species. Although smallmouth bass ( Micropterus dolomieu ) and yellow perch ( Perca flavescens ) consumed fewer Rusty Crayfish than expected based on relative prey abundance, predators consumed similar sized Crayfish of all species. Further, our results indicated that predators likely avoid O. rusticus because they have larger chelae than congeners, and that behavioral differences did not appear to contribute substantially to Crayfish selection at the whole lake scale. Our results suggest that selective predation based on chelae size is one of the primary drivers of this species replacement. Selective predation commonly accelerates exotic dominance over native prey and should be considered explicitly in exotic species investigations. La predation selective peut determiner la composition d'une communaute. Nous avons organise une etude de terrain pour determiner si la predation selective par les poissons explique la dominance de la population d'ecrevisse rustique, Orconectes rusticus , dans un lac du nord du Wisconsin. L'hypothese initiale etait que les poissons predateurs evitent de consommer O. rusticus plutot que ses congeneres O. propinquus et O. virilis parce que O. rusticus , soit atteint une taille superieure, soit est plus agressive que ses congeneres. Sur la base d'un travail experimental precedent, nous avons suppose que les predateurs consommeraient des individus de l'ecrevisse rustique petits plutot que ceux d'autres especes en raison des differences de comportement entre les especes d'ecrevisses. Bien que le blackbass a petite bouche ( Micropterus dolomieu ) et la perche jaune ( Perca flavescens ) aient consomme moins d'ecrevisses rustiques que prevu en considerant l'abondance relative des proies, les predateurs ont consomme les ecrevisses de meme taille des differentes especes. De plus, nos resultats ont indique que les predateurs evitent probablement O. rusticus parce qu'elles ont des pinces plus grandes que leurs congeneres et que les differences de comportement ne semblent pas contribuer substantiellement a la selection des ecrevisses a l'echelle du lac etudie. Nos resultats suggerent que la predation selective fondee sur la taille des pinces est le principal facteur du remplacement des especes. La predation selective accelere habituellement la dominance des especes exotiques par rapport aux especes indigenes et devrait etre davantage prise en compte dans les investigations sur les especes exotiques. ]
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assessing ecosystem vulnerability to invasive Rusty Crayfish orconectes rusticus
Ecological Applications, 2011Co-Authors: Julian D. Olden, Jake Vander M Zanden, Pieter T J JohnsonAbstract:Despite the widespread introduction of nonnative species and the heterogeneity of ecosystems in their sensitivity to ecological impacts, few studies have assessed ecosystem vulnerability to the entire invasion process, from arrival to establishment and impacts. Our study addresses this challenge by presenting a probabilistic, spatially explicit approach to predicting ecosystem vulnerability to species invasions. Using the freshwater-rich landscapes of Wisconsin, USA, we model invasive Rusty Crayfish (Orconectes rusticus) as a function of exposure risk (i.e., likelihood of introduction and establishment of O. rusticus based on a species distribution model) and the sensitivity of the recipient community (i.e., likelihood of impacts on native O. virilis and O. propinquus based on a retrospective analysis of population changes). Artificial neural networks predicted that approximately 10% of 4200 surveyed lakes (n = 388) and approximately 25% of mapped streams (23 523 km total length) are suitable for O. rusticus introduction and establishment. A comparison of repeated surveys before vs. post-1985 revealed that O. virilis was six times as likely and O. propinquus was twice as likely to be extirpated in streams invaded by O. rusticus, compared to streams that were not invaded. Similarly, O. virilis was extirpated in over three-quarters of lakes invaded by O. rusticus compared to half of the uninvaded lakes, whereas no difference was observed for O. propinquus. We identified 115 lakes (approximately 3% of lakes) and approximately 5000 km of streams (approximately 6% of streams) with a 25% chance of introduction, establishment, and extirpation by O. rusticus of either native congener. By identifying highly vulnerable ecosystems, our study offers an effective strategy for prioritizing on-the-ground management action and informing decisions about the most efficient allocation of resources. Moreover, our results provide the flexibility for stakeholders to identify priority sites for prevention efforts given a maximum level of acceptable risk or based on budgetary or time restrictions. To this end, we incorporate the model predictions into a new online mapping tool with the intention of closing the communication gap between academic research and stakeholders that requires information on the prospects of future invasions.
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behavioural and growth differences between experienced and naive populations of a native Crayfish in the presence of invasive Rusty Crayfish
Freshwater Biology, 2009Co-Authors: Nicole M Hayes, Julian D. Olden, Katrina J Butkas, Jake Vander M ZandenAbstract:Summary 1. Species invasions are a leading threat to native species and ecosystems. How populations of native species respond to the presence of invasive species will ultimately determine their long-term persistence. 2. In this study, we capitalise on a unique opportunity to compare the behaviour and growth of naive and experienced virile Crayfish (Orconectes virilis Hagen) populations in the presence of invasive Rusty Crayfish (O. rusticus Girard). In behavioural trials, experienced O. virilis (coexisted with O. rusticus for >30 years) showed more aggressive behaviour than their naive counterparts. Naive O. virilis retreated from aggressive interactions with O. rusticus 38% more often than experienced O. virilis. Experienced O. virilis spent 39% more time occupying shelter than naive O. virilis. 3. There were also differences in O. rusticus behaviour: O. rusticus spent 24% more time occupying shelter with naive O. virilis relative to experienced O. virilis. 4. In field mesocosm experiments with O. rusticus, naive O. virilis declined in body mass by 1% while experienced O. virilis’ body mass increased by 6%, thus highlighting the potential population-level implications of the previously observed behavioural effects. 5. Our work demonstrates significant behaviour and growth differences between naive and experienced O. virilis in the presence of invasive O. rusticus. Whether this difference is the result of phenotypic plasticity or evolution by natural selection remains to be determined. Either way, this area of inquiry has implications for managing native populations and species in an increasingly invaded world.
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interactions among invaders community and ecosystem effects of multiple invasive species in an experimental aquatic system
Oecologia, 2009Co-Authors: Pieter T J Johnson, Julian D. Olden, Christopher T Solomon, Jake Vander M ZandenAbstract:With ecosystems increasingly supporting multiple invasive species, interactions among invaders could magnify or ameliorate the undesired consequences for native communities and ecosystems. We evaluated the individual and combined effects of Rusty Crayfish (Orconectes rusticus) and Chinese mystery snails [Bellamya (=Cipangopaludina) chinensis] on native snail communities (Physa, Helisoma and Lymnaea sp.) and ecosystem attributes (algal chlorophyll a and nutrient concentrations). Both invaders are widespread in the USA and commonly co-occur within northern temperate lakes, underscoring the importance of understanding their singular and joint effects. An outdoor mesocosm experiment revealed that while the two invaders had only weakly negative effects upon one another, both negatively affected the abundance and biomass of native snails, and their combined presence drove one native species to extinction and reduced a second by >95%. Owing to its larger size and thicker shell, adult Bellamya were protected from Crayfish attack relative to native species (especially Physa and Lymnaea), suggesting the co-occurrence of these invaders in nature could have elevated consequences for native communities. The per capita impacts of Orconectes (a snail predator) on native snails were substantially greater than those of Bellamya (a snail competitor). Crayfish predation also had a cascading effect by reducing native snail biomass, leading to increased periphyton growth. Bellamya, in contrast, reduced periphyton biomass, likely causing a reduction in growth by native lymnaeid snails. Bellamya also increased water column N:P ratio, possibly because of a low P excretion rate relative to native snail species. Together, these findings highlight the importance of understanding interactions among invasive species, which can have significant community- and ecosystem-level effects.
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fish predation and trapping for Rusty Crayfish orconectes rusticus control a whole lake experiment
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Catherine L Hein, Brian M Roth, Anthony R Ives, Jake Vander M ZandenAbstract:Improved methods are needed for the prevention and control of invasive species. We investigated the potential to control a Rusty Crayfish (Orconectes rusticus) population in an isolated lake in northern Wisconsin by trapping adult Crayfish and restricting fishing, thereby increasing fish populations and predation on small Crayfish. Over a 3 year period, traps and predatory fishes removed substantial portions of the Rusty Crayfish population. We used an age-structured population model to determine which removal method had the largest effect on Crayfish population growth rates. Because more Crayfish were vulnerable to and removed by fish predation than by trapping, fish predation caused a larger decline in the population growth rate. However, trapping removed Crayfish with the highest reproductive value and caused the largest decline in population growth rate per individual Crayfish removed. Consideration of density-dependent responses to removal is necessary to predict long-term effects on Rusty Crayfish p...
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using bioenergetics and stable isotopes to assess the trophic role of Rusty Crayfish orconectes rusticus in lake littoral zones
Canadian Journal of Fisheries and Aquatic Sciences, 2006Co-Authors: Brian M Roth, Catherine L Hein, Jake Vander M ZandenAbstract:Crayfish often dominate freshwater ecosystems and can have strong effects on littoral habitat and biota through foraging. However, there is substantial debate regarding the trophic role of Crayfish and implications of their foraging behavior on littoral ecosystems. We created a bioenergetics model for Rusty Crayfish (Orconectes rusticus )t o determine how growth and prey choice constrain Crayfish consumption, which affects littoral ecosystems. We simulated over 6400 potential Rusty Crayfish diets by varying the abundance of important prey. We judged how Crayfish prey choice affects the amount and identity of prey that Crayfish must consume to match observed growth. We compared our model predictions with stable isotope evidence from 10 northern Wisconsin lakes to determine energy sources and trophic position of Rusty Crayfish relative to other invertebrates. Our diet simulations and stable isotope analysis con- curred that Crayfish of all ages are primarily predators. Individuals that do not feed on zoobenthos must therefore con- sume large quantities of less desirable food such as macrophytes, which are an important component of littoral habitat. Resume : Les ecrevisses dominent souvent les ecosystemes d'eau douce et peuvent, par leur recherche de nourriture, avoir de profonds effets sur l'habitat littoral et les organismes qui y vivent. Cependant, il existe un important debat sur le role trophique des ecrevisses et les consequences de leur comportent de recherche de nourriture sur les ecosystemes littoraux. Nous avons mis au point un modele bioenergetique pour l'ecrevisse americaine (Orconectes rusticus )a fin de determiner comment la croissance et le choix des proies limitent la consommation des ecrevisses, ce qui affecte les ecosystemes littoraux. Nous avons fait des simulations impliquant plus de 6400 regimes alimentaires potentiels d'ecrevisses en faisant varier l'abondance des proies principales. Nous avons determine comment le choix des proies par les ecrevisses affecte le nombre et l'identite des proies que l'ecrevisse doit consommer pour expliquer la croissance observee. Nous avons compare les predictions de notre modele et les donnees d'analyse des isotopes stables provenant de 10 lacs du nord du Wisconsin afin de determiner les sources d'energie et la position trophique de l'ecrevisse americaine par rapport aux autres invertebres. Nos simulations de regimes alimentaires et l'analyse des isotopes stables s'accordent pour trouver que les ecrevisses de tous les âges sont principalement des predateurs. Les individus qui ne se nourrissent pas de zoobenthos doivent consommer de grandes quantites de nourriture moins desirable, telle que les macrophytes qui forment un compartiment relativement important de l'habitat littoral. (Traduit par la Redaction)
