Cacapon River Research Articles

English

Abstract Crayfish are an aquatic fauna of conservation concern, yet regional studies are lacking on zoogeography and life history. We compared recent and historical species distribution data and assessed conservation standings of native and nonindigenous crayfish of the Potomac River Basin in West Virginia. From 2007–2011, a total of 1764 crayfish were collected from 159 sites. Data collection included species abundance, morphometrics, and life history parameters. Percentages of the number of individuals of each species of the total catch were 36.3% (Cambarus bartonii), 34.6% (Faxonius obscurus), 23.4% (Faxonius virilis), 3.6% (Procambarus cf. zonangulus) and 2.0% (Cambarus carinirostris). Cambarus bartonii was present throughout the drainage, F. obscurus was collected primarily from the North Branch, South Branch, and Cacapon river watersheds, and C. carinirostris was only collected in the South Branch watershed. Two nonnative species, F. virilis and P. cf. zonangulus, were only present in tributaries downstream of the Cacapon River watershed. Spinycheek crayfish (Faxonius limosus) were not collected during our survey, which suggests its possible extirpation from the West Virginia portion of its range. Our zoogeographic and life history data could serve as a baseline for future conservation-oriented monitoring efforts of the Potomac River watershed.

Habitat Characteristics That Influence the Occurrence of Wood Turtles at the Southern Limits of Their Range in the Central Appalachians

Abstract Topographical features and environmental variables form geographic range boundaries and limit species' distributions. Studies of Wood Turtle (Glyptemys insculpta) limitations in the northern reaches of their geographic range are fairly well documented; however, few studies exist that investigate ecological factors that affect distribution at the southern extent of their range. Our objectives were to 1) determine aquatic and terrestrial habitat characteristics relevant to Wood Turtle presence or absence and 2) determine the approximate southern geographic boundary of Wood Turtles in the Cacapon River Watershed, West Virginia, USA. We conducted random surveys of 100 sites along the Lost and North rivers during summer 2010, and 64% contained Wood Turtles. Proximity to the Cacapon River, elevation, soil pH, canopy cover, and slope influenced the presence of Wood Turtles. In addition, Wood Turtles occurred at sites with higher herbaceous species richness and diversity, especially in locations along th...

Conflicting natural and anthropogenic threats reduce nest success in centrarchid fishes

As anthropogenic presence in riverine systems increases, it is essential to understand the associated impacts on ecologically important species such as centrarchid fishes. We tested the hypothesis that the conflicting pressures of natural factors (e.g., predation threat), the perceived threat of human traffic, and the impacts of habitat degradation would negatively influence centrarchid nest success. We surveyed centrarchid nesting areas in the Cacapon River, West Virginia, USA and collected a suite of biotic and habitat variables for each nest found. From these data, we analyzed site selection and nest success in three centrarchid species and male flight response to perceived harm in the most common (longear sunfish, Lepomis megalotis). We detected patterns of nest site selection in all species surveyed, with a large degree of overlap in influential variables. Males did not select for nest sites near in-stream cover, which appeared to reduce nest success by acting as refugia for benthic brood predators. However, the protection provided by cover dampened the magnitude of response to perceived harm. Therefore, the pressures of human and natural threats were contradictory, likely reducing fitness and fecundity. Future restoration procedures should seek to conserve nesting habitat by limiting the impacts of human presence.

Community-Level Response of Fishes and Aquatic Macroinvertebrates to Stream Restoration in a Third-Order Tributary of the Potomac River, USA

Natural stream channel design principles and riparian restoration practices were applied during spring 2010 to an agriculturally impaired reach of the Cacapon River, a tributary of the Potomac River which flows into the Chesapeake Bay. Aquatic macroinvertebrates and fishes were sampled from the restoration reach, two degraded control, and two natural reference reaches prior to, concurrently with, and following restoration (2009 through 2010). Collector filterers and scrapers replaced collector gatherers as the dominant macroinvertebrate functional feeding groups in the restoration reach. Before restoration, based on indices of biotic integrity (IBI), the restoration reach fish and macroinvertebrate communities closely resembled those sampled from the control reaches, and after restoration more closely resembled those from the reference reaches. Although the macroinvertebrate community responded more favorably than the fish community, both communities recovered quickly from the temporary impairment caused by the disturbance of restoration procedures and suggest rapid improvement in local ecological conditions.

A New State Record Of Allocapnia simmonsi Kondratieff And Voshell (Plecoptera: Capniidae) From West Virginia, U.S.A., With Additional Records From Pennsylvaniaand Virginia

The eastern Nearctic snowfly genus Allocapnia (Plecoptera: Capniidae) is presently recognized by 44 species (Stark and Baumann, 2005; Grubbs, 2006). A recent checklist of the stoneflies of West Virginia (Tarter and Nelson, 2006) reported 135 species. During a recent winter collecting trip, the rare snowfly Allocapnia simmonsi Kondratieff and Voshell was collected for the first time from the eastern panhandle of West Virginia. Previous records of A. simmonsi have been reported from Pennsylvania (Earle, 1994) and Virginia (Kondratieff and Voshell, 1981; Kondratieff and Kirchner, 1987). The eastern panhandle of West Virginia is located in the Ridge and Valley Physiographic Province. All collection localities were in the Cacapon River drainage, a tributary of the Potomac River. The majority of the landscape in the Cacapon River drainage is deciduous forest with some agriculture. Agriculture is mostly confined to the valleys of this area with the majority of the hillsides being forested. This is a rural area of West Virginia with the region’s agricultural economy lead by the poultry and beef industry. The poultry industry has grown rapidly since the early 1990s which has triggered concerns with water quality in this area (Constantz et al., 1995). Stonefly collections from the eastern panhandle of West Virginia appear to be under represented and future collecting may add new state records. Stonefly species collected in association with A. simmonsi from West Virginia included A. curiosa Frison, A. granulata (Claassen), A. nivicola (Fitch), A. pygmaea (Burmeister), A. rickeri Frison, Paracapnia angulata Hanson, Prostoia completa (Walker), Strophopteryx fasciata (Burmeister), Taeniopteryx burksi Ricker and Ross, and T. maura (Pictet). Our efforts and previous collecting have not yielded large collections of this species. Allocapnia simmonsi, which is extremely rare in PennVolume 119, Number 3, May and June 2008 303

Two-phase sampling to estimate river-wide populations of freshwater mussels

Two-phase sampling provides a statistical framework for combining data from qualitative and quantitative sampling methods. It is a useful approach when the survey objective is a drainage-wide estimate of mussel density and the cost of qualitative sampling is small relative to the cost of quantitative sampling. This survey design has several advantages including: 1) no need for a priori classification of stream reaches into sampling strata, 2) allocation of sampling effort so that more time is spent sampling where mussels are at higher density and less time is spent sampling where mussels are not present, 3) the ability to evaluate the relationship between qualitative and quantitative estimates of density, and 4) efficient allocation of effort so that more stream reaches can be surveyed compared to quantitative-only sampling designs with similar effort. The survey design consists of sampling as many sites as possible during a qualitative 1st phase and sampling far fewer sites during a quantitative 2nd phase. In 1995, we used a 2-phase sampling design to estimate the distribution and abundance of freshwater mussels in riffle habitat in the Cacapon River, West Virginia. Our estimate of river-wide surface density of freshwater mussels in riffles was 0.59/m2 (SE = 0.14). We used resampling simulation based on our data and determined that the most effective 2nd-phase sampling strategy was to sample a low to moderate proportion of low-density sites and a high proportion of high-density sites.

Optimal sampling design for estimating spatial distribution and abundance of a freshwater mussel population

AbstractWe compared the ability of simple random sampling (SRS) and a variety of systematic sampling (SYS) designs to estimate abundance, quantify spatial clustering, and predict spatial distribution of freshwater mussels. Sampling simulations were conducted using data obtained from a census of freshwater mussels in a 40 × 33 m section of the Cacapon River near Capon Bridge, West Virginia, and from a simulated spatially random population generated to have the same abundance as the real population. Sampling units that were 0.25 m2 gave more accurate and precise abundance estimates and generally better spatial predictions than 1-m2 sampling units. Systematic sampling with ≥2 random starts was more efficient than SRS. Estimates of abundance based on SYS were more accurate when the distance between sampling units across the stream was less than or equal to the distance between sampling units along the stream. Three measures for quantifying spatial clustering were examined: Hopkins Statistic, the Clumping Inde...

Estimating Survival and Recruitment in a Freshwater Mussel Population Using Mark-recapture Techniques

We used a mark-recapture method and model averaging to estimate apparent survival, recruitment and rate of population growth in a native freshwater mussel population at a site on the Cacapon River, which is a tributary to the Potomac River. Over 2200 Elliptio complanata, E. fisheriana and Lampsilis cariosa were uniquely tagged over a period of 4 y. Recapture probabilities were higher in spring and summer than in winter except for L. cariosa which had a low probability of recapture regardless of time of year. All three species had high annual adult survival rates (>90%) with lower estimated survival of small (≤55 mm) mussels (43%–69%). The variation in apparent survival over time was similar for all three species. This suggests that whatever environmental variables affect survival of mussels in this site affected all three species the same. Recruitment rates were low (1–4%) for both E. complanata and L. cariosa, with E. fisheriana having several periods of high (15–23%) recruitment. Distribution within the site was affected by both downstream and upstream movement, though movement rates were generally <1%. Average population growth rates for E. complanata (λ = 0.996, se = 0.053), L. cariosa (λ = 0.993, se = 0.076) and E. fisheriana (λ = 1.084, se = 0.276) indicated static populations. Population growth rate approximating 1.0 suggests this site supports a stable freshwater mussel population through a life history strategy of low but constant recruitment and high annual adult survival.

Application of adaptive cluster sampling to low-density populations of freshwater mussels

Freshwater mussels appear to be promising candidates for adaptive cluster sampling because they are benthic macroinvertebrates that cluster spatially and are frequently found at low densities. We applied adaptive cluster sampling to estimate density of freshwater mussels at 24 sites along the Cacapon River, WV, where a preliminary timed search indicated that mussels were present at low density. Adaptive cluster sampling increased yield of individual mussels and detection of uncommon species; however, it did not improve precision of density estimates. Because finding uncommon species, collecting individuals of those species, and estimating their densities are important conservation activities, additional research is warranted on application of adaptive cluster sampling to freshwater mussels. However, at this time we do not recommend routine application of adaptive cluster sampling to freshwater mussel populations. The ultimate, and currently unanswered, question is how to tell when adaptive cluster sampling should be used, i.e., when is a population sufficiently rare and clustered for adaptive cluster sampling to be efficient and practical? A cost-effective procedure needs to be developed to identify biological populations for which adaptive cluster sampling is appropriate.

Observations on the Natural and Artificial Propagation of the Smallmouth Black Bass, Micropterus Dolomieu

Counts of smallmouth black bass nests in the same sections of the South Branch of the Potomac, the Cacapon, and the Shenandoah Rivers are reported over a period of several seasons. The 4-year record for the South Branch of the Potomac indicates little change in the smallmouth black bass population. The number of nests varied between 50.7 and 73.2 and averaged 58.1 for each mile of stream. The results of fry counts from wild nests showed an average of 2,159 fry in each nest in the South Branch of the Potomac, 2,210 in the Cacapon River, and 1,998 in the Shenandoah River. One important characteristic of natural propagation in these rivers is the simultaneous occurrence of spawning in any section of stream having similar conditions. Evidence is supplied to support the theory that a long, drawn-out spawning season in artificial ponds is due to annoyance of the brood fish. The importance of attendance by the male fish at the nest is pointed out. Examples in pond culture are given to demonstrate that there are other factors involved in the spawning of smallmouth black bass besides temperature. These factors are annoyance, over-crowding of the brood fish, and lack of provision for greater individual privacy among the brood bass during their spawning season. In general, productivity of fry apparently increases with age and size of the brood fish.

A Comparison of Four Eastern Smallmouth Bass Streams

Abstract Four smallmouth bass streams in the Potomac River watershed are compared. In the largest stream, the Shenandoah River near Berryville, Virginia, the fingerling bass (Micropterus dolomieu) grew to an average length of 4.25 inches during 1936, whereas in the South Branch of the Potomac near Romney, West Virginia, fingerlings attained a length of 2.75 inches by the end of the summer. In the Shenandoah River and probably also in its North Fork, bass grow rapidly and attain the legal size of 10 inches in three years, but in the South Branch of the Potomac and in the Cacapon River from four to six years or more are required for the fish to grow to legal size. The muddy condition of the Shenandoah and North Fork for long periods during the summer affects the success of natural propagation. These streams also have extensive riffle areas over limestone ledges where bass find shelter while feeding. In the South Branch of the Potomac and in the Cacapon River the riffles are short and little shelter is avail...