Stream-dwelling Crayfish Research Articles

Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA.

Two new species of stream-dwelling crayfish, Cambarus lapidosus, the Stony Fork Crayfish, and Cambarus burchfielae, the Falls Crayfish, are described from the Yadkin River basin in western North Carolina, USA, using an integrative taxonomic approach consisting of morphological, genetic, and biogeographic data. Both species were previously considered to be members of the widely distributed Cambarus species C complex, which occurs throughout mid-Atlantic Slope river basins; however, they are in fact morphologically and genetically more similar to the Cambarus robustus species complex from interior basins in the south-central Appalachians, indicating Atlantic basin stream capture of an Interior basin faunal group has occurred in this region. Both new species described herein can be differentiated from these two complexes, and each other, by several morphological characteristics. Cambarus lapidosus and C. burchfielae are differentiated from C. species C by the absence of cervical spines and the presence of 1-2 subpalmar tubercles on the chelae in most specimens; both species are less-punctate across the areola than C. aff. robustus. Cambarus burchfielae is further differentiated from C. lapidosus, C. species C, and C. aff. robustus by the presence of a narrower and sparsely punctate areola, a single weak row of tubercles on the mesial margin of the palm, and the absence of tubercles on the dorsal surface of the dactyl. The newly described species are genetically sister taxa and together are most similar by genetic distance to undescribed members of the C. robustus species complex from the nearby (~30 km) Watauga River basin and most phylogenetically similar to C. aff. robustus from the adjacent New River basin; both are interior basin drainages. The newly-described species are endemic to the Blue Ridge Mountains of western North Carolina and have restricted distributions (<100 km2-150 km2) in small (<4th order) tributaries to the Yadkin River. Cambarus lapidosus is known only from the upper Stony Fork watershed and C. burchfielae is known only from the upper reaches of the adjacent Lewis Fork watershed; both species likely qualify for conservation status protections under narrow geographic range criteria.

Taxonomic Standing and Genetic Surveillance of the Spiny Scale Crayfish (Cambarus jezerinaci) in Southeastern Kentucky

&#x0D; In Southeastern Kentucky a small, cold stream-dwelling crayfish, Cambarus jezerinaci, located in the Kentucky and Cumberland River basin may be a part of a species complex. A previous study done in 2008 on the cytochrome oxidase 1 gene (CO1) of C. jezerinaci and Cambarus parvoculus, a sister species in the region, identified a third genetically distinct lineage most similar to C. jezerinaci currently retained as Group B C. jezerinaci. Group B is as different from the true species as the true species is to C. parvoculus, a total CO1 difference greater than 5%. Morphological characteristics were also compared between C. jezerinaci and C. parvoculus with only rostral states being significant to species identification. However, in light of new genetic lineages previous research suggested the separation of them before morphological comparisons. In 2022 and 2023 research was conducted on both the genetics and morphological differences of C. jezerinaci within two river basins to better understand the taxonomic standing of this crayfish. Determining the true status of C. jezerinaci within these two river basins is important to the conservation of these animals. Continuing genetic research helps us to grow our understanding of what it means to be a species in the modern age and also allows us to learn about the biodiversity and speciation process itself. Given the rapidly changing climate, it is imperative to catalog the true diversity of our freshwater streams and develop conservation action plans for endemic species such as C. jezerinaci.

Digging ability and digging performance in a hyporheic gravel-dwelling crayfish, the hairy crayfish Cambarus friaufi (Hobbs 1953) (Decapoda: Astacidae: Cambaridae)

Abstract Crayfishes are known for their ability to construct burrows, although there is intra- and interspecific variation in the complexity and reliance on such burrows. Crayfishes historically have been classified into ecological groupings based on their reliance on their burrow and the burrows connection to the water table. These ecological classifications, however, do not completely account for the behavioral diversity throughout crayfishes. One group of crayfishes that do not necessarily fit into these ecological classifications are members of the invalid subgenus Glareocola of Cambarus Erichson, 1846, which includes four species: C. brachydactylus (Hobbs, 1953), C. friaufi (Hobbs, 1953), C. polypilosus (Loughman &amp; Williams, 2018), and C. williami (Bouchard &amp; Bouchard 1995). All four species inhabit streams characterized by loose chert gravel, which creates ample interstitial spaces and potential access to the streambed’s hyporheic zone. We studied how one member of the Glareocola group, C. friaufi, exhibits unique morphological and behavioral adaptations that enable individuals to dig into the hyporheic zone of their natural chert substrate. We found that C. friaufi was sexually monomorphic regarding the relationship between body size and claw size, which contrasts findings from other stream-dwelling crayfish species. By evaluating the digging ability and digging performance of C. friaufi and sand, pea gravel, and their natural chert substrate, we also demonstrate how their digging ability is highly adapted to their natural chert substrate. Individuals of C. friaufi were either unable to dig or rarely dig underneath substrates other than chert. We discuss our results considering the behavioral ecology and natural history of the crayfishes within this enigmatic group.

Cambarus ectopistes sp. nov., a new stream-dwelling crayfish (Decapoda: Cambaridae) from the French Broad, Pigeon, and Nolichucky River watersheds in the Appalachian Mountain region of North Carolina and Tennessee, USA.

The Cataloochee Crayfish, Cambarus ectopistes sp. nov., is a large, stream-dwelling crayfish that occupies a narrow noncontiguous distribution within the Appalachian Mountain region running through the Upper Tennessee River basin, in the French Broad, Pigeon, and Nolichucky watersheds along the Tennessee and North Carolina border. It is split from the southernmost extent of the C. robustus species complex, and is morphologically and genetically most similar to a second undescribed member of the group endemic to the upper Nolichucky River watershed in North Carolina. Cambarus ectopistes sp. nov. can be distinguished from other members of the C. robustus complex and co-distributed congeners by a combination of characters, including body size, coloration, and morphology of the chela and rostrum. The new species is typically found in channel and edge habitats of moderate to large perennial streams with large cobbles and boulders.

Streamflow regimes and geologic conditions are more important than water temperature when projecting future crayfish distributions

Ongoing changes in climate are expected to alter current species’ habitat and potentially result in shifts in species distributions. While climatic conditions are important to a species’ ability to persist in an area, for many taxa, other environmental factors, such as geology, land cover, and topography, are also important for providing suitable habitat. Furthermore, aquatic species experience changes in climatic conditions through the effect precipitation and air temperature have on streamflow regimes and water temperature. In this study, species distribution models (SDMs) for ten stream-dwelling crayfish species were generated using a maximum entropy approach across the Mobile River Basin in the southeastern United States. SDMs were developed using model-generated contemporary estimates of streamflow and water temperature as well as geologic, topographic, and land cover data. Future distributions were then projected using global climate model (GCM) projections of streamflow and water temperature. Geology, topography, and streamflow appear to be more important predictors of suitable habitat than water temperature for crayfish species within the Mobile River Basin. Species distributions regulated by limited influences from stream flow and water temperature displayed relatively small changes in projected future habitat distributions based on various GCM scenarios. When shifts in species distributions were projected into the future, these shifts did not appear to follow a northward retreat or expansion, likely due to the limited impact of water temperature on the modeled distributions of suitable habitat for these species. Furthermore, species’ habitat distribution responses among future climate scenarios were variable within and among species and did not vary unidirectionally with increased severity of climate change as realized through increased warming patterns.

Cambarus franklini, a new crayfish (Decapoda: Cambaridae) from the Catawba River Basin in western North Carolina, USA.

A new species of stream-dwelling crayfish, Cambarus franklini, the South Mountains crayfish, is described from the upper South Fork Catawba River basin in western North Carolina, USA using morphological and genetic data. Cambarus franklini was previously considered a member of the widespread and morphologically variable Cambarus species C complex and is morphologically most similar to an undiagnosed member of the group native to the upper Catawba River basin in NC. Cambarus franklini can be differentiated from this species group by several morphological characteristics including: lacking a well-defined double row of tubercles along the mesial margin of the palm, possessing a more weakly convergent and longer acumen, and conspicuous blue-green and red coloration, particularly throughout the telson and along the distal margins of the rami. This species is phylogenetically most similar to Cambarus johni, Cooper, 2006, another former member of the Cambarus species C group. Cambarus franklini has a limited geographic range (100 km2) and is currently known only from the Henry and Jacob Fork watersheds in the South Mountains region of the Eastern Blue Ridge foothills.

Cambarus polypilosus, a new species of stream-dwelling crayfish (Decapoda: Cambaridae) from the Western Highland Rim of Tennessee, USA.

Cambarus polypilosus sp. nov. is a stream-dwelling crayfish endemic to tributaries in the Buffalo and lower Duck River drainage, and a reach of the lower Tennessee River in the Western Highland Rim of West-Central Tennessee, U.S.A. The new species is closely allied to the three members of the former subgenus Glareocola, but can be differentiated from each by a combination of characters, including body size, coloration, spination, setation, and form I male gonopod morphology. Several meristic measurements and ratios also differentiate C. polypilosus sp. nov. from Cambarus friaufi, to which it is morphologically most similar. Cambarus polypilosus sp. nov. appears to be common in cherty gravel and cobble habitats, where it is typically found in interstices at depths of 0.3 m or more below the substrate surface.

Landscape- and local-scale habitat influences on occupancy and detection probability of stream-dwelling crayfish: implications for conservation

Crayfish are ecologically important in freshwater systems worldwide and are imperiled in North America and globally. We sought to examine landscape- to local-scale environmental variables related to occupancy and detection probability of a suite of stream-dwelling crayfish species. We used a quantitative kickseine method to sample crayfish presence at 102 perennial stream sites with eight surveys per site. We modeled occupancy (psi) and detection probability (P) and local- and landscape-scale environmental covariates. We developed a set of a priori candidate models for each species and ranked models using (Q)AICc. Detection probabilities and occupancy estimates differed among crayfish species with Orconectes eupunctus, O. marchandi, and Cambarus hubbsi being relatively rare (psi 0.60) with high detection probability (0.81). Detection probability was often related to local habitat variables current velocity, depth, or substrate size. Important environmental variables for crayfish occupancy were species dependent but were mainly landscape variables such as stream order, geology, slope, topography, and land use. Landscape variables strongly influenced crayfish occupancy and should be considered in future studies and conservation plans.

Cambarus (C.) appalachiensis, a new species of crayfish (Decapoda: Cambaridae) from the New River Basin of Virginia and West Virginia, USA.

Cambarus (Cambarus) appalachiensisis a stream-dwelling crayfish endemic to the greater New River basins of Virginia and West Virginia. The new species is morphologically most similar toCambarus sciotensis.Cambarus appalachiensis can be differentiated fromC. sciotensisby its more elongated chelae which possess a single mesial row of tubercles, reduced to no tuberculation on the dorsal-longitudinal ridge of the dactyl, and reduced lateral impression. Cambarus sciotensis has a more subrectangular chelae with two rows of mesial margin tubercles on the chelae, as well as both a pronounced dorsal-longitudinal ridge and pronounced lateral impression. Several chelae meristic ratios also differentiate C. appalachiensis from C. sciotensis. Within the New, Gauley, and lower portions of the Greenbrier basins C. appalachiensis is the dominant tertiary burrowing Cambarus species, and as such, is considered stable across its range.

Multi-scale ecological filters shape the crayfish microbiome

A general and practical understanding of the processes that drive microbiome assembly and structure are paramount to understanding organismal biology, health, and evolution. In this study of stream-dwelling crayfish, we conceptualized colonization of microbial symbionts as a series of ecological filters that operate at the environment, host, and host microsite levels, and identified key ecological processes at each level. A survey of Cambarus sciotensis in western Virginia, USA, showed that the local environment and host microsites interact to create complex patterns of microbial diversity and composition. An in situ experiment confirmed a prevailing effect of host microsite on microbial composition, and also showed that an ectosymbiotic worm (Annelida; Branchiobdellida) which feeds on biofilms and other symbionts had significant effects on microbial composition of the host carapace, but not gills. Bacterial communities of the carapace were taxonomically rich and even, and correlated with microbial communities of the ambient environment. Conversely, communities on gills were less diverse and dominated by two taxa with potential functional significance: Comamonadaceae and Chitinophagaceae. The bacterial communities of the gills appear to be tightly coupled to host biology, and those of the carapace are mostly determined by environmental context. Our work provides the first characterization of the crayfish microbiome and shows how multi-scale and experimental studies of symbiont community assembly provide valuable insights into how the animal microbiome is structured under conditions of natural complexity. Furthermore, this study demonstrates that metazoan symbiont taxa, i.e., the branchiobdellidans, can alter microbiome assembly and structure.

English

Abstract Cambarus parrishi is a rare, stream-dwelling crayfish endemic to the upper Hiwassee River watershed in northeastern Georgia and western North Carolina. A two year survey of C. parrishi at 22 sites across 4 streams was conducted to identify microhabitat associations and population characteristics, and represents the most comprehensive study of this species within Georgia. Field sampling expanded the range of C. parrishi to four separate streams in Georgia and resulted in the capture of 141 individuals. Generalized linear modeling of C. parrishi density demonstrated strong associations near stream banks with rough substrates composed of abundant cobbles and small boulders. Cambarus parrishi were reproductively active from September through October and reached sexual maturity earlier than indicated by historical data. Five possible age classes were defined with an unbalanced 1.7:1 (females:males) sex ratio. Cambarus parrishi exists mostly on federally-managed lands at high elevations. However, development activities that introduce fine substrates and eliminate heterogeneous habitats preferred by most stream-dwelling crayfishes could threaten this species. Although this study increased knowledge of the range of C. parrishi, additional data on population, habitat use, life history, and occurrences in other tributaries within the watershed are still needed.

Cambarus (Puncticambarus) callainus, a new species of crayfish (Decapoda: Cambaridae) from the Big Sandy River basin in Kentucky, Virginia, and West Virginia, USA.

Cambarus (Puncticambarus) callainus, new species, is a stream-dwelling crayfish endemic to the Big Sandy River basin in Kentucky, Virginia, and West Virginia. Within the basin, C. callainus occurs in the Levisa, Tug, and Russell fork watersheds. The new species is morphologically and genetically most similar to Cambarus veteranus, which is endemic to the Upper Guyandotte River basin of West Virginia. The new species can be differentiated from C. veteranus by its more lanceolate rostrum (width less than 50% length), slightly more obtuse suborbital angle, and less well-defined lateral impression at the base of the chelae.

Cambarus (C.) hatfieldi, a new species of crayfish (Decapoda:Cambaridae) from the Tug Fork River Basin of Kentucky, Virginia and West Virginia, USA.

Cambarus (Cambarus) hatfieldiis a stream-dwelling crayfish that appears to be endemic to the Tug Fork River system of West Virginia, Virginia, and Kentucky. Within this region, itis prevalent in all major tributaries in the basin as well as the Tug Fork River's mainstem. The new species is morphologically most similar toCambarus sciotensisandCambarus angularis.It can be differentiated fromC. sciotensisby its squamous, subtrinagular chelae compared to the elongate triangular chelae ofC. sciotensis; its shorter palm length/palm depth ratio (1.9) compared toC. sciotensis (2.3); and a smaller areola length/total carapace length ratio (30.4% vs.36.5% respectively). Cambarus hatfieldi can be differentiated from C. angularis by its smaller areola length/total carapace length ratio (30.4% vs. 36.7% respectively); a smaller rostrum width/rostral length ratio (59.4% vs. 67.2% respectively); its rounded abdominal pleura as compared to the subtruncated pleura of C. angularis; the length of the central projection and mesial process of C. hatfieldi which both extend to the margin of the gonopod shaft or slightly beyond the margin compared to the central projection of C. sciotensis and C. angularis where both extend well beyond the margin of the gonopod shaft.

Cambarus (P) theepiensis, a new species of crayfish (Decapoda:Cambaridae) from the coalfields region of Eastern Kentucky and Southwestern West Virginia, USA.

Cambarus (Puncticambarus) theepiensis is a stream-dwelling crayfish that appears to be endemic to the junction of the Cumberland Mountains with the Appalachian Plateau in West Virginia and Kentucky. Within this region, it is prevalent in the Guyandotte and Twelvepole basins of West Virginia, the Little Sandy River and Levisa Fork basins of Kentucky, and tributaries of the Big Sandy River shared by both states. The new species is morphologically most similar to Cambarus robustus and Cambarus sciotensis. It can be differentiated from C. robustus by its broad rostrum, with subparallel, thick-ened margins compared to the narrow, converging rostrum with reduced rostral margins of C. robustus.; larger areola width/length ratio (26 %) than C. robustus (22 %); and mottled color pattern compared to the monotypic color pattern of C. robustus. Canibarus theepiensis can be differentiated from C. sciotensis by the presence of a distinct lateral impression on the chelae compared to the absence of a lateral impression in C. sciotensis; constant thickness of the rostral margin compared to the gradation of rostral thickness in C. sciotensis; greater rostrum width/ length ratio in C. theepiensis (63.1 %) compared to C. sciotensis (57.2 %); and a central projection on the gonopod that is the same length as the mesial process, compared to a central projection that extends past the tip of the mesial process in C. sciotensis.

Cambarus (Puncticambarus) smilax, a new species of crayfish (Crustacea: Decapoda: Cambaridae) from the Greenbrier River basin of West Virginia

Cambarus (Puncticambarus) smilax is a stream-dwelling crayfish that appears to be endemic to the Greenbrier River basin in the Valley and Ridge province of West Virginia. Within the Greenbrier system it occurs primarily in tributaries to the Greenbrier mainstem, with stable populations in the East and West Fork, and Thorny, Knapp, and Deer creeks. The new species is morphologically most similar to C. (P.) robustus, from which it can be distinguished by a combination of the following characters: adult palm length comprising 73–76% of palm width as opposed to 63–70% in C. (P.) robustus; ventral surface of chela of cheliped with 0–2 subpalmar tubercles compared to 3–6 subpalmar tubercles in C. (P.) robustus; lack of tubercles on the dorsal surface of chela; longer, more tapering, less rectangular rostrum (47–52% rostrum width/length ratio) compared to C. (P.) robustus shorter, less tapering rectangular rostrum (54–63% rostrum width/length ratio); and the central projection of the form-I male gonopod curved ≤90 degrees to the shaft.

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.

Distribution, Habitat Use and Life History of Stream-dwelling Crayfish in the Spring River Drainage of Arkansas and Missouri with a Focus on the Imperiled Mammoth Spring Crayfish (Orconectes marchandi)

Abstract The Mammoth Spring crayfish (Orconectes marchandi) is listed as endangered by the American Fisheries Society's Endangered Species Committee and globally impaired by the Missouri Natural Heritage Database. Recorded at only three locations in the Spring River watershed (southern Missouri and northern Arkansas), little information exists on its range, associations with other crayfish and habitat selection. We sampled stream-dwelling crayfish with kicknets and quadrat samplers during spring-summer over 2 y in the Spring River drainage to determine distribution, relative density, habitat use, species associations, and life history characteristics of O. marchandi and other associated crayfish species. Nine crayfish species were collected in the Spring River watershed including a previously unrecorded invasive species, O. neglectus chaenodactylus, that appears to have replaced the native O. eupunctus from a portion of the watershed where it was previously abundant. The known distribution of O. marchandi...

COMPARISON OF THE GILL MORPHOLOGY AND BRANCHIAL CHAMBERS IN TWO FRESH-WATER CRAYFISHES FROM TASMANIA: ASTACOPSIS FRANKLINII AND PARASTACOIDES TASMANICUS

ABSTRACT Branchial complements, gill morphology, gill surface areas, gill volumes, branchial volumes, and branchial space of the stream-dwelling parastacid crayfish Astacopsis franklinii and the burrowing Parastacoides tasmanicus are compared. A reduction in gill number in Parastacoides results from the absence of pleurobranchiae on the fifth, sixth, and seventh thoracic segments and the extreme reduction of the pleurobranch on segment 8. There is a tendency for gill filaments to be longer in Parastacoides and the terminal spines on the filaments of the podobranchiae are longer, hooked rather than straight, and occur more frequently in this species. Most of the respiratory exchange area is provided by the podobranchiae. Linear regression equations (log transformed data) describing the allometric relationship between body size and gill area, gill volume, branchial volume, and branchial space are provided for both species. Parastacoides has a significantly greater size-related gill area and branchial volume than Astacopsis and, since there are no differences in gill volume, there is also a significant increase in branchial space. Much of this additional space appears to be created towards the posterior of the branchial chamber. The differences between the two species are interpreted as adaptations for the burrowing, amphibious life-style adopted by Parastacoides. We suggest that they serve primarily to facilitate oxygen uptake, reduce the tendency for the gills to become clogged, and aid in flushing of the branchial chamber in hypoxic waters with a very high particle content; they are seen as providing secondary benefits to assist survival during the often prolonged periods when the burrows lack free water.

Resource Partitioning by Stream-dwelling Crayfish: The Influence of Body Size

The crayfishes Orconectes luteus and 0. punctimanus are sympatric in over 200 km of the Jacks Fork and Current rivers in S-central Missouri. The combinations of substrate particle size, current velocity, depth and macrophyte cover used by youngof-the-year and adults of each species tended to be distinct. Orconectes punctimanus was more restricted in its use of habitats. Young-of-the-year were strongly associated with macrophyte cover and shallow water, and adults with larger substrate particles; both life stages preferred slow current velocities. Orconectes luteus was more evenly distributed over most of the habitats. Young-of-the-year used current velocities and substrate particle sizes somewhat more in proportion to their availability than did adults, which were concentrated within the higher ranges of both of these variables. Laboratory choice experiments involving combinations of species and size classes indicated that crayfish dominance was a function of body size and that habitat use by one size class could be modified when larger individuals of the same or a different species were present. The young of 0. punctimanus hatched earlier and grew faster than did those of 0. luteus. Orconectes punctimanus therefore maintained a distinct size advantage throughout its life cycle. Orconectes punctimanus probably inhabited its preferred set of microhabitat conditions and excluded 0. luteus from these areas. Because much of the remaining stream habitat was unsuitable for 0. punctimanus, competitive exclusion did not occur. Other factors, most notably fish predation, probably complement physical factors and species interactions in determining the distributional patterns of these crayfishes. INTRODUCTION The crayfishes of any particular aquatic habitat generally are limited to one or very few species, even if many species occur in the geographical region (e.g., Williams, 1954). Closely related species commonly exhibit disjunct distributions (see Bovbjerg, 1970, for a review) and an introduced species may rapidly replace one that occurred naturally (Capelli, 1982). The mechanisms involved in displacement or in maintaining species separation are not well understood, but crayfish behavior often gives insight into probable causes. It was well documented by Bovbjerg (1953, 1956), Penn and Fitzpatrick (1963) and Capelli (1982) that crayfish are aggressive, and Capelli and Munjal (1982) recorded interspecific encounters leading to attack in laboratory experiments. Intraspecific attacks are probably common either during the molting period, or by adults on juveniles after production of a maternal pheromone ceases (Little, 1976). Crayfish are mobile, and migrate (Momot, 1966; Flint, 1977), and disperse from areas of high density to areas of low density (Bovbjerg, 1964). Such behaviors have led several investigators to conclude that disjunct crayfish distributions were due to competitive exclusion (Aiken, 1965; Fitzpatrick, 1967; Crocker and Barr, 1968; Capelli and Magnuson, 1983). There are also situations where closely related species coexist in what appears to be a common habitat. Given their aggressive tendencies, different species existing in proximity is more surprising than is the exclusion of one species by another. The question why some crayfish are sympatric and others are not was the impetus for this study. In the Current and Jacks Fork rivers in S-central Missouri, Orconectes luteus (Creaser) and 0. punctimanus (Creaser) coexist in over 200 km of stream. The objectives 1 The Unit is sponsored by the U.S. Fish and Wildlife Service, the Missouri Department of Conservation and the University of Missouri.

Home Range of Crayfish Orconectes juvenalis

Home Range of Crayfish Orconectes juvenalis