Crayfish Communities Research Articles

Crayfish communities converge over succession in beaver pond metacommunities

Abstract Metacommunity theory predicts that the relative importance of regional and local processes structuring communities will change over ecological succession. Determining effects of these processes on taxonomic and evolutionary diversity in spatially structured freshwater habitats of different successional stages may greatly improve understanding of the maintenance of diversity across temporal and spatial scales. In this study, we evaluated crayfish diversity at local and regional scales in pond metacommunities undergoing secondary succession from beaver (Castor canadensis) disturbance. Following theoretical predictions from metacommunity ecology of the increasing importance of local processes over succession, we hypothesised a decline in crayfish local and β diversity over succession from stronger local structuring as the older ponds may provide less suitable habitat than streams. Crayfish species and phylogenetic diversity were evaluated in beaver pond metacommunities and reference headwater streams located in three catchment regions. DNA sequences from the mitochondrial cytochrome oxidase I gene were used to assign crayfish to species for community and phylogenetic diversity tests. Local and β diversity were contrasted across beaver ponds ranging in age from 24 to 70 years and as a function of metacommunity processes. Counter to predictions, local species diversity among streams and the successional stages of ponds categorised by age class (24–39 years; 42–57 years; 60–70 years) did not differ, but community and phylogenetic convergence occurred in the oldest pond ecosystems. Crayfish community composition differed between the youngest and oldest ponds, resulting from higher abundance in the youngest ponds and community convergence in the oldest ponds. The association between community composition and the environment was strongest in streams and decoupled with pond age. In contrast, the correlation between intraspecific haplotype composition and the environment increased over succession. Among the three metacommunities, the regional crayfish species diversity arose from a combination of the temporal and environmental drivers from beaver‐constructed ecosystems and dispersal limitation within catchments. This study represents the first investigation of the taxonomic and phylogenetic diversity response to the successional stages of beaver pond metacommunities. The detection of differential crayfish composition and haplotype sorting to pond age suggests a role for local structuring and further indicates that future studies should acknowledge succession in shaping species diversity at local and regional scales. Dispersal limitation within catchment regions probably contributes to the evolution of crayfish species diversity in metacommunities and the overall maintenance of biodiversity. The results support a transition in community and freshwater ecology from a recent emphasis on spatial processes towards the integration of temporal drivers to better identify regulators of taxonomic and phylogenetic diversity across scales.

English

Abstract Comprehensive surveys are critical to conserve and monitor crayfish communities, imperiled species, and detect crayfish invasions. The Missouri portion of the North Fork White River drainage (MONFWR) was never comprehensively surveyed, but adjacent drainage surveys suggested it could harbor species of conservation concern (SOCC). We surveyed the MONFWR to determine crayfish species richness, distributions of potential SOCC, and potential invasive species. We included recent sampling of the Arkansas portion of the drainage for a more holistic assessment of the entire drainage. We examined potential changes in crayfish communities after three decades at 22 previously sampled MONFWR locations. We also collected the first habitat association data for the endemic, Faxonius longidigitus. We detected eight taxa; none that were not known from the drainage. Faxonius neglectus chaenodactylus and Cambarus hubbsi were SOCC; F. n. chaenodactylus was common and abundant in the MONFWR; C. hubbsi was detected at only one site in Arkansas. Faxonius neglectus neglectus and Faxonius virilis were each detected only once and are likely introduced. Intermittent streams harbored diversity and abundance rivaling perennial segments. We observed no notable temporal differences between 22 historical and current samples. Faxonius longidigitus, detected at few sites in low numbers, was associated with deeper waters and larger substrates.

Life history and ecology of the Greenbrier Crayfish Cambarus smilax Loughman, Simon & Welsh, 2011 (Decapoda: Astacoidea: Cambaridae)

Abstract We studied the life history and ecology of the Greenbrier Crayfish, Cambarus smilax (Loughman, Simon & Welsh, 2011) in Thorny Creek and the West Fork of the Greenbrier River, West Virginia from August 2010 to July 2011. We gathered data on morphology, reproductive status, habitat preference, and the prevalence of claw regeneration for each monthly sampling event. We collected Form I males every single month at Thorny Creek location, and every single month besides December at West Fork Greenbrier location. Females exhibited active glair glands during May to July, with oviposition in June to August. Fecundity ranged from 71 to 179, with an average of 121 eggs per female. Cambarus smilax preferred different microhabitats at each of our two study sites. It was primarily collected in run microhabitats at Thorny Creed, but primarily collected at West Fork Greenbrier within pool microhabitats, potentially due to competitive displacement from C. chasmodactylus (James, 1966). Our study provides the first information regarding the life history of C. smilax and sheds light on the ecological implications of competition between locations with different crayfish communities.

Establishing water and crayfish community baselines for streams harboring the federally threatened Big Sandy Crayfish (Cambarus callainus)

Coal slurry, one of the main pollutants created from coal mining, can spill from retention ponds and end up in aquatic ecosystems, potentially harming aquatic life. An area especially affected by this issue due to the heavy presence of coal mining is the central Appalachian coalfields. Aquatic life native to the coalfields where spills occur serve as a source of take for two federally listed crayfish: threatened Cambarus callainus and endangered Cambarus veteranus. Although this is a prominent issue, no baseline physiochemical data exists for streams harboring C. callainus. The main goal of this effort was to establish physiochemical and biological baselines of coalfields streams by measuring common water quality parameters and the crayfish community for one year at historic/current C. callainus sites. Results indicated there were not strong correlations between any chemical driver and total crayfish or crayfish species presence/absence. This data will be used to generate a response protocol to coal slurry spills to aid coalfields crayfish and other aquatic taxa in the future.

Spatial and temporal patterns in native and invasive crayfishes during a 19‐year whole‐lake invasive crayfish removal experiment

Abstract Understanding where, when, and how native species persist in the face of invasive species‐driven ecosystem change is critical for invasive species management and native species conservation. In some cases, ecological interactions among native and invasive species are spatially structured, and spatial segregation can be a key coexistence mechanism for ecologically similar taxa. We evaluated 19‐years of spatially explicit crayfish community data from a long‐term whole‐lake experiment, which includes 8 years of invasive rusty crayfish (Faxonius rusticus) removal followed by 11 years of post‐removal data collection. We quantified the within lake spatiotemporal patterns of virile crayfish (F. virilis) and rusty crayfish, and relate their dynamics to site‐level habitat conditions. In response to removal efforts, rusty crayfish catch rates declined by >95%, and native virile crayfish catch rates increased by more than 20‐fold. Ten years after ceasing removals, rusty crayfish have stayed at this relatively low abundance, and the virile crayfish population has remained stable. During removal, rusty crayfish abundances decreased non‐uniformly throughout the lake. Only after rusty crayfish populations were at their lowest levels did the native virile crayfish population begin to show signs of a recovery. Virile crayfish recovery was highly localized within the lake, and likely influenced by habitat and rusty crayfish abundance. Initially, virile crayfish made the most substantial resurgence in an area of the lake with rocky habitat conditions, but through time their distribution shifted into adjacent suboptimal macrophyte and muck habitats as rusty crayfish became more abundant in nearby areas. In general, when the two species overlapped in space, virile crayfish abundance stayed low, or the population shifted to adjacent areas with fewer competitively dominant rusty crayfish. Our results suggest that habitat heterogeneity allowed virile crayfish to maintain a foothold despite high rusty crayfish densities. Removal efforts led to the recovery of virile crayfish, and spatial segregation facilitated both species coexisting at comparable abundances for a decade. Our results highlight that invasive species control, even in the absence of complete eradication, can benefit native species and that spatially structured interactions can promote coexistence.

Water Quality Monitoring for the Central Appalachian Coalfields Crayfish

Primary economic drivers over the years in the central Appalachian coalfields include coal mining, timbering, fossil fuel extraction, and all-terrain vehicle tourism. These industries cause impacts such as sedimentation, elimination of headwater streams (resulting from valley fills), destruction of riparian vegetation, and increased physiochemical pollution in montane streams. As a result of this significant habitat destruction, two species of endemic crayfishes, Cambarus callainus and Cambarus veteranus, were both federally listed in April 2016. This study will sample 12 selected sites – four degraded streams, four medium-impacted streams, and four reference condition streams – within the coalfields region of Kentucky, Virginia, and West Virginia. Sampling will occur for one year, alternating monthly between two sets of six sites. General crayfish sampling will occur at each site to document the crayfish community present. Water quality monitoring will be split into four categories: long-term, point-source, photometer, and water samples analyzed for heavy metal content. Understanding the chemical composition of the target species’ habitat will enable us to properly and efficiently aid C. callainus and C. veteranus conservation efforts.

Big Sandy Crayfish (Cambarus callainus) Habitat Affinity in Proximity to Bridges and Assessed via Radio Telemetry

Cambarus callainus (Big Sandy Crayfish) is a federally threatened species endemic to the coalfields of Kentucky, Virginia, and West Virginia. Existing datasets involving this species reflect broad/seasonal natural history trends, but conservation managers are still in need of a fine-scale, high resolution understanding of daily microhabitat utilization and movement patterns. The WVDOT has identified multiple locations within C. callainus range where in-stream bridge infrastructure requires complete reconstruction in a timely manner. Construction projects occurring within waterways supporting C. callainus could represent a threat to the crayfish community, but the extent of such effects is currently unknown. To identify potential disruptions to C. callainus populations we aim to determine the extent of site fidelity, peak and minimum activity periods, and preferred microhabitat utilization assessed by radiotracking C. callainus during and after active construction. Collected data will be interpreted to determine further conservation and management practices necessary for protection of C. callainus. Findings will allow organizations such as the WVDOT to move forward with necessary infrastructure projects while mitigating further anthropogenic impact to this vulnerable species.

Injury frequency and severity in crayfish communities as indicators of physical habitat quality and water quality within agricultural headwater streams.

Crayfishes (Decapoda) are common inhabitants of agricultural headwater streams in the Midwestern USA that have been impacted by physical habitat degradation and contamination by agricultural pollutants. The frequency and severity of injuries within crayfish communities are indicators of crayfish aggression, which is influenced by physical, chemical, and biotic factors. Previous studies have not evaluated the relationships of the frequency and severity of crayfish injuries with physical habitat quality, water quality, and biotic factors within agricultural headwater streams. Understanding these relationships will assist with determining if crayfish injury variables can serve as an indicator of physical habitat quality or water quality in these small degraded streams. We sampled crayfishes, documented the frequency and type of injuries, and measured instream habitat and water chemistry in 2014 and 2015 within 12 agricultural headwater streams in Indiana, Michigan, and Ohio. We documented five native crayfish species from 1641 adult captures. The most abundant species were Faxonius rusticus, Faxonius immunis, and Faxonius propinquus. Linear mixed effect model analyses indicated that four crayfish injury response variables were positively correlated (p < 0.05) with crayfish density, physical habitat quality, and water velocity diversity and that crayfish injury response variables were more strongly correlated with crayfish density than physical habitat quality or water quality. Our results indicate that response variables describing the severity and frequency of crayfish injuries can be effective indicators of physical habitat quality in agricultural headwater streams.

When invaders collide: competition, aggression, and predators affect outcomes in overlapping populations of red swamp (Procambarus clarkii) and rusty (Faxonius rusticus) crayfishes

Non-native crayfishes can have large impacts on biodiversity and the provisioning of ecosystem services in freshwaters. In 2015 we discovered an established population of the globally widespread red swamp crayfish (Procambarus clarkii) in the North Shore Channel of the Chicago Area Waterway System. This population overlaps with a population of rusty crayfish (Faxonius rusticus), a previous invader that is widely distributed and usually the dominant crayfish species across the Great Lakes region. If P. clarkii continues to spread in the Great Lakes region it will frequently encounter F. rusticus. Factors such as water clarity, competition for food when limited, and susceptibility to predation may alter P. clarkii’s ability to become established and spread. We sampled the overlapping populations and found that P. clarkii are significantly larger than F. rusticus. Next, we conducted lab experiments to examine the outcomes of competition between these species for shelter and food. F. rusticus were significantly more likely to seek shelter when threatened, while P. clarkii were significantly more likely to respond aggressively. P. clarkii won more competitions for food. Finally, we conducted field experiments to investigate rates of predation on each species and found that P. clarkii are predated significantly more often. Our results suggest that P. clarkii is dominant in interactions with F. rusticus but that higher rates of predation, likely occurring because P. clarkii is less likely to flee from threats, mitigate these benefits. We suggest that P. clarkii will dominate crayfish communities in water with low clarity, but not in clear-water habitats where visual predators are more effective.

Variation in native crayfish agonistic response to the invasion of the rusty crayfish Orconectes rusticus (Girard, 1852)

The consequences of biological invasions warrant continued research on the mechanisms underlying the spread of exotic species, yet interspecific behavioral interactions are largely overlooked as a contributing factor or consequence of introductions of exotic species. Our study evaluates how native crayfish species, Cambarus bartonii (Fabricius, 1798) and Orconectes propinquus (Girard, 1852), respond behaviorally to the invasion of the rusty crayfish, Orconectes rusticus (Girard, 1852) in the Upper Susquehanna River Basin, NY, USA using experiments in a semi-natural setting. We found significant effects of species, sex, year, novelty to invasion, and abiotic environment on the proportion of time native crayfish species exhibited agonistic behavior toward invading rusty crayfish. Cambarus bartonii females were generally more aggressive than males, particularly in year two, but the opposite was true for O. propinquus as males were more aggressive than females. Behavioral variation in recipient crayfish communities is a potential mechanism influencing the spread of introduced crayfishes although future study is necessary to assess the relative extent of such influence. The mechanisms driving the spread of invasive species are clearly complex and interactive, but the development of effective management plans is limited by the completeness of our understanding, which thus far has been lacking a substantial ethological component.

An analysis of suspected crayfish invasions in Missouri, U.S.A.: evidence for the prevalence of short-range translocations and support for expanded survey efforts

Reports of alien crayfish invasions are increasingly common and often associated with well-documented ecological effects including native crayfish biodiversity declines. Because most regions in the U.S. and Canada have not been surveyed to detect the presence and gauge the threat status of such invasions, management agencies lack information on the magnitude of problems in their respective jurisdictions. Our objectives were to catalog, confirm and summarize suspected crayfish invasions that were reported in one U.S. state in recent years. Data were also examined for potential spatial patterns, prevalence of certain species as invaders and effects to native crayfishes. We collected reports of crayfish introductions/invasions from 1998–2014, and attempted to confirm them via sampling. We catalogued 34 reports and confirmed 31 as suspected invasions involving 6 invading species. Procambarus acutus was easily the most frequent invader, and all invading species were native to at least part of Missouri. Most suspected invasions involved species that were legal for commercial sale in the state, but many also involved non-commercial species that are described as “narrow-range endemics.” Invading species were abundant, dominating crayfish communities, at several sites. Native species have apparently declined or been displaced at several locations. Our results suggest the potential for many unreported crayfish invasions in the U.S. and Canada, including those caused by shorter-range (e.g., intrastate) translocations. Ecoregions featuring high crayfish diversity could be threatened with significant declines of native species with narrow ranges. Increased survey efforts in these regions are warranted to estimate threat levels and provide agencies with information to support management actions.

The behavioural response of the invasive signal crayfish Pacifastacus leniusculus to experimental dewatering of burrows and its implications for eradication treatment and management of ponds with crayfish

Invasive non-indigenous crayfish threaten indigenous crayfish and aquatic communities. Biocide treatment to eradicate unwanted populations has been tried on small water bodies in the UK and a few other countries. It needs to be applied to the whole water body occupied by crayfish, so partial dewatering may reduce the cost of biocide. The whole population must be in the submerged dosed area, because if some individuals remain in exposed areas they may avoid treatment and hence eradication will not be achieved. This study looks at the response of signal crayfish Pacifastacus leniusculus to exposure of occupied burrows, in tanks and in the banks of a dewatered pond. Some crayfish emerged from exposed burrows by day (34% in tanks, 9% in field); the rest remained in burrows until after dark. In tanks, 96% of crayfish vacated exposed burrows on the first night when submerged burrows were available, but when all burrows were exposed, poorer-quality submerged refuges (open-ended tubes) and competition between crayfish kept subordinate individuals in the damp exposed burrows (32.5%). Subordinates did not vacate exposed burrows until dominant crayfish were removed. In the field, most crayfish emerged in 1–2 nights, but 0.5% remained alive in burrows six nights after exposure. In tank and field, about half of the crayfish climbed up onto dry exposed areas. In light of these findings, we recommend that if dewatering is a precursor to biocide treatment, exposed areas should be tested for presence of crayfish. If dewatering is for other management the potential for terrestrial roaming to other sites should be considered.

The role of size preference in prey selection ofAmphiuma means

Abstract. The two-toed amphiuma, Amphiuma means, is a large aquatic salamander and a potentially important predator of crayfish. However, little is known about the effects of predation by A. means on crayfish communities. This study was carried out to determine if there is a size preference in A. means predation on crayfish. A. means was expected to prefer medium sized crayfish in accordance with the optimal foraging theory because they were more energetically rewarding than smaller crayfish but easier to capture than larger crayfish. Seven similarly-sized A. means were placed in individual aquatic mesocosms. Six crayfish of the subgenus Scapulicambarus, two from each of three size categories, were also placed in each tub. The percent mortality and location of the crayfish in the tub were observed for 11 days. A. means had a significant preference for medium-sized crayfish on day four, but there were no significant differences among predation rates by the final day. Small crayfish had the lowest predation...

Rapid range expansion of rusty crayfish Orconectes rusticus (Girard, 1852) in the John Day River, Oregon, USA

The rusty crayfish, Orconectes rusticus (Girard, 1852), native to the eastern U.S., was discovered west of the Rocky Mountains in the John Day River in Oregon in 2005. In the five years since then, the known range of Orconectes rusticus has more than doubled to 145 river km along the mainstem of the river and populations have achieved high densities in several locations. To arrive at this estimate, the present study employed commercial crayfish traps, D-frame kick nets, and snorkel surveys to assess crayfish communities in the upper John Day basin. Natural dispersal, multiple introductions, a more thorough survey of the study area, or a combination of these factors could account for the expansion of the known distribution O. rusticus within the basin. The limit of O. rusticus expansion in the John Day River and broader Columbia River Basin, and the likely consequences for invaded ecosystems remain to be resolved.

Crayfish Fauna of Southeastern Pennsylvania: Distributions, Ecology, and Changes Over the Last Century

Abstract We describe the current distributions and relative abundances of southeastern Pennsylvania's crayfish; changes in the region's crayfish fauna over the last century; and, where pertinent, the relationship of the current fauna to site-specific characteristics, basin-wide attributes, and exotic crayfish. The crayfish fauna currently inhabiting the region bears little resemblance to the historical assemblage. Whereas historical surveys yielded Orconectes limosus and Cambarus bartonii, both native species, recent collections produced eight species including five exotics. Many areas occupied by exotic Orconectes no longer support O. limosus. Cambarus bartonii was found in a number of invaded systems, but was typically a minor component of the crayfish community and may not be able to persist in those systems indefinitely. The distribution of Cambarus (Puncticambarus) sp., an undescribed member of the Cambarus acuminatus complex, was extremely limited, with populations only found in four streams, all of...

Use of smartphones (iPhone, Android, etc.) for the field identification of European crayfish

Species identification keys are the most precise and unambiguous tools to properly identify a specimen down to the species or infra-species level. This is especially true when the key is richly illustrated with precise pictures or videos. Recent smartphones (iPhone, Android, etc.) can access through the 3G network to an unlimited and rapidly growing set of multimedia data on each species (photos, videos, audios). They become convenient tools to use in the field instead of traditional paper field-guides with a limited number of illustrations. A student project at the University of Nice, France, proposed to adapt to smartphones the Holdich and Vigneux “key to crayfish in Europe ”. A prototype, in English, has been prepared and presented to the European Crayfish Congress in Poitiers, France, 26–29 October, 2010. It needs now to be discussed with taxonomy and field specialists in order to (1) increase the number of photos and videos and (2) complete and improve its audio part. Then, a multilingual version could be designed, so that field specialists of all European countries may use it. As the database underlying the project is wiki-compatible, a multilingual version could be designed as a collaborative effort within the crayfish community. Data on each species (biology, ecology, distribution, etc.) could be added in a second phase, as a geolocalisation module is linked to the database. Then the identification of invasive species could be quickly related to maps, in order to alert the crayfish community.

Status and Distribution of Orconectes williamsi (Williams' Crayfish) in Arkansas, with New Records from the Arkansas River Drainage

Orconectes williamsi (Williams' Crayfish) is a rare stream-dwelling crayfish that is endemic to the upper White River basin of Arkansas and Missouri. It was described in the 1960s from a type locality in Madison County, AR, and the three localities named in the description comprise the published range of the species in Arkansas. In contrast, 27 locations have been reported in Missouri. This study surveyed a semi-random selection of stream sites in the Arkansas portion of this range in order to characterize the crayfish communities and evaluate the status of O. williamsi in Arkansas. A total of 2372 crayfishes were collected at 68 sites, including 197 Williams' Crayfish from 23 sites. Orconectes meeki meeki (Meek's Crayfish) was the crayfish species most commonly associated with O. williamsi, occurring sympatrically at 87% of sites occupied by O. williamsi. Orconectes williamsi was found in small streams, with coarse substrates and no aquatic vegetation. Orconectes williamsi showed a strong preference for riffle habitats. Due to its limited range and habitat requirements, O. williamsi is moderately imperiled in Arkansas and should be considered rare and vulnerable range-wide.

The influence of age-specific habitat selection by a stream crayfish community (Orconectes spp.) on secondary production

We examined the hypothesis that secondary production of a community of stream crayfish (Orconectes spp.) depended upon the available suite of channel units (e.g., riffle, run, pool) and that age-specific use of channel units was the important underlying mechanism. Nine cohorts of each of three species over a 10-year period at two sites on the Jacks Fork River, Missouri, USA, were sampled. Cohort-production estimates were calculated for specific channel units: riffles, runs, pools, backwaters and emergent vegetation patches. Orconectes luteus was the most productive species with similar production across channel units. Production of O. ozarkae and O. punctimanus was significantly greater in vegetation patches than other channel units. There were no species by channel unit differences in production between the two sites. Although total site production for some species substantially changed over the 10-year period, relative production differences between habitats remained temporally stable. Differences in mean production between channel units were largely due to age-class habitat use rather than differences related to growth. Some channel units particularly susceptible to common anthropogenic activities that result in hydrograph alterations and homogenization of physical habitat, e.g., backwaters, vegetation patches, and pools, were particularly important as high production areas for two species. A variety of channel units appears necessary for maintaining the high secondary production and diversity of crayfish in this system.

Invasion of the Upper Susquehanna River Watershed by Rusty Crayfish (Orconectes rusticus)

Abstract Orconectes rusticus (rusty crayfish) has spread from its original range throughout much of northeastern North America. Invading rusty crayfish can completely replace native crayfish and impact other parts of the community through changes in consumption, disturbance, and other effects. Our main objectives were to document rusty crayfish distribution in streams of the upper Susquehanna River watershed, NY, and to determine the extent of changes in crayfish community composition since the last major survey. We sampled streams during 1999–2005 to describe the current distribution of crayfish species and to document short-term temporal changes. To determine long-term changes in species composition and distribution, we compared our data to museum specimen collection records. We found significant changes in the crayfish community; our surveys found 2 species not previously reported from the upper Susquehanna River watershed and failed to find 2 species previously reported. We also found that rusty crayf...

Multivariate Analysis of Ecological Data Using CANOCO

Preface 1. Introduction and data types 2. Using Canoco 5 3. Experimental design 4. Basics of gradient analysis 5. Permutation tests and variation partitioning 6. Similarity measures and similarity-based methods 7. Classification methods 8. Regression methods 9. Interpreting community composition with functional traits 10. Advanced use of ordination 11. Visualising multivariate data 12. Case study 1: variation in forest bird assemblages 13. Case study 2: search for community composition patterns and their environmental correlates: vegetation of spring meadows 14. Case study 3: separating the effects of explanatory variables 15. Case study 4: evaluation of experiments in randomised complete blocks 16. Case study 5: analysis of repeated observations of species composition from a factorial experiment 17. Case study 6: hierarchical analysis of crayfish community variation 18. Case study 7: analysis of taxonomic data with linear discriminant analysis and distance-based ordination methods 19. Case study 8: separating effects of space and environment on oribatid community with PCNM 20. Case study 9: performing linear regression with redundancy analysis Appendix A. Glossary Appendix B. Sample data sets and projects Appendix C. Access to Canoco and overview of other software Appendix D. Working with R References Index to useful tasks in Canoco 5 Index.