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Diversity and Habitat Distributions of Ground-Surface Spiders (Araneae) in Kings Mountain National Military Park, South Carolina
Abstract
We surveyed ground-surface spider populations in Kings Mountain National Military Park, Blacksburg, SC, monthly from August 2009 through July 2010 using pitfall traps to collect spiders at 2 sites in each of 3 forest habitat types: riparian zones, dry forest areas, and ridgetop habitats. Of the 902 adult spiders collected, we identified 848 to species, representing 85 species in 22 families. Although each habitat type supported a unique set of species, each also shared species with the other habitat types. High Chao–Sorenson similarity values were seen in comparisons of both forest and ridgetop as well as forest and riparian habitats. We used the first 3 Hill numbers, species richness (⁰D), Shannon exponential (¹D), and inverse Simpson (²D) indices, to compare diversity among habitat types. Species richness was significantly higher in the riparian compared to the ridgetop habitat, while both the Shannon exponential and inverse Simpson indices were significantly higher in the riparian habitat than in either the forest or ridgetop habitats, which did not differ from each other. Diversity was not significantly different between any pairs of sites within habitats with the exception of coverage-based species richness in the dry forest habitat. Within a habitat type, the 2 forest sites had the highest Chao–Sorenson similarity value, followed by the 2 ridgetop sites, with the 2 riparian sites being the least similar to each other.
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Hill numbers (or the effective number of species) have been increasingly used to quantify the species/taxonomic diversity of an assemblage. The sample‐size‐ and coverage‐based integrations of rarefaction (interpolation) and extrapolation (prediction) of H ill numbers represent a unified standardization method for quantifying and comparing species diversity across multiple assemblages.
We briefly review the conceptual background of H ill numbers along with two approaches to standardization. We present an R package iNEXT (i N terpolation/ EXT rapolation) which provides simple functions to compute and plot the seamless rarefaction and extrapolation sampling curves for the three most widely used members of the H ill number family (species richness, S hannon diversity and S impson diversity). Two types of biodiversity data are allowed: individual‐based abundance data and sampling‐unit‐based incidence data.
Several applications of the iNEXT packages are reviewed: (i) Non‐asymptotic analysis: comparison of diversity estimates for equally large or equally complete samples. (ii) Asymptotic analysis: comparison of estimated asymptotic or true diversities. (iii) Assessment of sample completeness (sample coverage) across multiple samples. (iv) Comparison of estimated point diversities for a specified sample size or a specified level of sample coverage.
Two examples are demonstrated, using the data (one for abundance data and the other for incidence data) included in the package, to illustrate all R functions and graphical displays.
Traditional woodland management created a mosaic of differently aged patches providing favorable conditions for a variety of arthropods. After abandonment of historical ownership patterns and traditional management and the deliberate transformation to high forest after World War II, large forest areas became darker and more homogeneous. This had significant negative consequences for biodiversity. An important question is whether even small-scale habitat structures maintained by different levels of canopy openness in abandoned coppiced forest may constitute conditions suitable for forest as well as open habitat specialists. We investigated the effect of canopy openness in former traditionally coppiced woodlands on the species richness, functional diversity, activity density, conservation value, and degree of rareness of epigeic spiders. In each of the eight studied locations, 60-m-long transect was established consisting of five pitfall traps placed at regular 15 m intervals along the gradient. Spiders were collected from May to July 2012. We recorded 90 spider species, including high proportions of xeric specialists (40%) and red-listed threatened species (26%). The peaks of conservation indicators, as well as spider community abundance, were shifted toward more open canopies. On the other hand, functional diversity peaked at more closed canopies followed by a rapid decrease with increasing canopy openness. Species richness was highest in the middle of the canopy openness gradient, suggesting an ecotone effect. Ordinations revealed that species of conservation concern tended to be associated with sparse and partly opened canopy. The results show that the various components of biodiversity peaked at different levels of canopy openness. Therefore, the restoration and suitable forest management of such conditions will retain important diversification of habitats in formerly coppiced oak forest stands. We indicate that permanent presence of small-scale improvements could be suitable conservation tools to prevent the general decline of woodland biodiversity in the intensified landscape of Central Europe.
Quantifying and assessing changes in biological diversity are central aspects of many ecological studies, yet accurate methods of estimating biological diversity from sampling data have been elusive. Hill numbers, or the effective number of species, are increasingly used to characterize the taxonomic, phylogenetic, or functional diversity of an assemblage. However, empirical estimates of Hill numbers, including species richness, tend to be an increasing function of sampling effort and, thus, tend to increase with sample completeness. Integrated curves based on sampling theory that smoothly link rarefaction (interpolation) and prediction (extrapolation) standardize samples on the basis of sample size or sample completeness and facilitate the comparison of biodiversity data. Here we extended previous rarefaction and extrapolation models for species richness (Hill number qD, where q = 0) to measures of taxon diversity incorporating relative abundance (i.e., for any Hill number qD, q > 0) and present a unified approach for both individual-based (abundance) data and samplebased (incidence) data. Using this unified sampling framework, we derive both theoretical formulas and analytic estimators for seamless rarefaction and extrapolation based on Hill numbers. Detailed examples are provided for the first three Hill numbers: q = 0 (species richness), q = 1 (the exponential of Shannon's entropy index), and q = 2 (the inverse of Simpson's concentration index). We developed a bootstrap method for constructing confidence intervals around Hill numbers, facilitating the comparison of multiple assemblages of both rarefied and extrapolated samples. The proposed estimators are accurate for both rarefaction and short-range extrapolation. For long-range extrapolation, the performance of the estimators depends on both the value of q and on the extrapolation range. We tested our methods on simulated data generated from species abundance models and on data from large species inventories. We also illustrate the formulas and estimators using empirical data sets from biodiversity surveys of temperate forest spiders and tropical ants.
The two forest-management practices of prescribed burning and thinning are techniques used to reduce heavy fuel loads that have resulted from years of fire suppression. Therefore, the National Fire and Fire Surrogate (NFFS) study was conducted to determine the effects of prescribed burning and thinning on different environmental factors. This study was conducted in the Clemson University Experimental Forest in South Carolina, one of the 13 NFFS sites in the United States, and examined the impacts of these management practices on spider populations. We used pitfall traps to sample ground-dwelling spiders to determine if changes in population levels had occurred one year following implementation of these practices. We collected a total of 1220 specimens of Araneae, representing 13 families. Results indicated that by 1-year post-treatment, spider populations had recovered following the initial (2001) burning and thinning. However, in 2002, when we compared the first post-burn samples to pre-burn samples in thin+burn plots, we found a significant decrease in the mean abundance of Agelenidae and Linyphiidae after the prescribed burn.
Biodiversity, a multidimensional property of natural systems, is difficult to quantify partly because of the multitude of indices proposed for this purpose. Indices aim to describe general properties of communities that allow us to compare different regions, taxa, and trophic levels. Therefore, they are of fundamental importance for environmental monitoring and conservation, although there is no consensus about which indices are more appropriate and informative. We tested several common diversity indices in a range of simple to complex statistical analyses in order to determine whether some were better suited for certain analyses than others. We used data collected around the focal plant Plantago lanceolata on 60 temperate grassland plots embedded in an agricultural landscape to explore relationships between the common diversity indices of species richness (S), Shannon's diversity (H'), Simpson's diversity (D1), Simpson's dominance (D2), Simpson's evenness (E), and Berger–Parker dominance (BP). We calculated each of these indices for herbaceous plants, arbuscular mycorrhizal fungi, aboveground arthropods, belowground insect larvae, and P. lanceolata molecular and chemical diversity. Including these trait-based measures of diversity allowed us to test whether or not they behaved similarly to the better studied species diversity. We used path analysis to determine whether compound indices detected more relationships between diversities of different organisms and traits than more basic indices. In the path models, more paths were significant when using H', even though all models except that with E were equally reliable. This demonstrates that while common diversity indices may appear interchangeable in simple analyses, when considering complex interactions, the choice of index can profoundly alter the interpretation of results. Data mining in order to identify the index producing the most significant results should be avoided, but simultaneously considering analyses using multiple indices can provide greater insight into the interactions in a system.
A guild of wandering spiders was studied in an oak-tuliptree-maple forest in northern Delaware. Specimens were collected by pitfall trapping and weather data recorded at weekly intervals over the summer season (3 months). A seasonal peak in species diversity (H') and species richness in midsummer was significantly correlated with prey abundance but not with seasonal temperature, humidity, or rainfall. Annual patterns of detritivore productivity in temperate forests and their influence on niche partitioning and seasonal abundance of species are discussed as a possible explanation. Spatial differences in species diversity were significantly correlated with the amount of litter and a measure of habitat space, but not with microclimatic moisture and temperature, vegetative diversity, or prey abundance. Physical aspects of the litter habitat, either as structural microhabitats or refuges from predation, are suggested as being important in regulating within-habitat species diversity. Interaction of diversity-regulating environmental factors in space and time are discussed.
Species composition and diversity of a guild of wandering spiders was studied by pitfall trapping over an elevational gradient in an Illinois streamside forest. Differences in flooding frequency and their effect on the litter habitat (removal and/or compression) account for a majority of the variation in the number of species between elevations. Changes in spider communities with elevation over the flooding gradient are indicative of a transition from a harsh to a moderate environment: (1) increased abundance and species diversity; (2) decreased dominance of flood tolerant species accompanied by increased dominance of species with specialized microhabitats found in complex litter; (3) greater similarity in species composition between sites; and, (4) a change in species-abundance curves from a geometric series to a lognormal distribution. The influence of the flooding regime in regulating community structure of spiders is discussed. A multiple regression equation including flood frequency and litter depth as variables was used to predict the impact of altered flooding regimes (due to reservoir construction downstream) on spider diversity.
Three commonly used measures of diversity, Simpson's index, Shannon's entropy, and the total number of species, are related to Renyi's definition of a generalized entropy. A unified concept of diversity is presented, according to which there is a continuum of possible diversity measures. In a sense which becomes apparent, these measures provide estimates of the effective number of species present, and differ only in their tendency to include or to ignore the relatively rarer species. The notion of the diversity of a community as opposed to that of a sample is examined, and is related to the asymptotic form of the species-abundance curve. A new and plausible definition of evenness is derived.
Biological Diversity provides an up-to-date, authoritative review of the methods of measuring and assessing biological diversity, together with their application. The book's emphasis is on quantifying the variety, abundance, and occurrence of taxa, and on providing objective and clear guidance for both scientists and managers. This is a fast-moving field and one that is the focus of intense research interest. However the rapid development of new methods, the inconsistent and sometimes confusing application of old ones, and the lack of consensus in the literature about the best approach, means that there is a real need for a current synthesis. Biological Diversity covers fundamental measurement issues such as sampling, re-examines familiar diversity metrics (including species richness, diversity statistics, and estimates of spatial and temporal turnover), discusses species abundance distributions and how best to fit them, explores species occurrence and the spatial structure of biodiversity, and investigates alternative approaches used to assess trait, phylogenetic, and genetic diversity. The final section of the book turns to a selection of contemporary challenges such as measuring microbial diversity, evaluating the impact of disturbance, assessing biodiversity in managed landscapes, measuring diversity in the imperfect fossil record, and using species density estimates in management and conservation.
Salt marshes are simple ecosystems characterized by extreme conditions; two abiotic factors appear to structure habitats: regular submergence and the resulting soil salinity. These ecosystems support highly specialized species that have a high conservation value. In the last ten years, invasion by Elymus athericus (Poaceae) has led to a major change in vegetation cover (including changes in micro-habitats architecture) in salt marshes of the Mont-Saint-Michel Bay (France). In this study, we tried to determine whether ecological structure and high conservation value of invaded salt marshes had been preserved using spiders as indicators. The functional groups, abundances and flood resistance abilities of spider communities were compared between initial and invaded stations during 2002 and 2003. Invasion by E. athericus had both positive and negative consequences for spider communities, in particular for the dominant halophilic species. Pardosa purbeckensis populations clearly declined in habitats invaded by E. athericus, whereas Arctosa fulvolineata seemed to benefit greatly from the invasion. Functional groups were strongly affected by the plant invasion. Relation between the habitat change (vegetal invasion) and changes in the spider communities (both in terms of functional groups and halophilic species) confirms the high value of this taxon as bioindicators. Lastly, we suggest using abundances of P. purbeckensis as a parameter likely to help monitoring further salt marsh evolutions (such as management).
Between 3500 and 4270m elevation (11,500-14,000 ft.) 174 pitfall jars were placed in a variety of habitats. In 1967, 71 species and 16,342 sepcimens of spiders, phalangids, mites, and ground beetles were collected. Species within the same genus usually occur in different habitats, as defined by vegetation cover and soil moisture. All tundra species, for which adequate records exist, also occur at elevations below tree-line. "Accidental" species of spiders may occur on the tundra, after having been blown up from lower elevations. Three species of arachnids differ in mean adult size between tundra areas 77km apart; one of these species also differs in size between 3650m and 4270m elevation. Many Colorado alpine tundra arachnid and carabid species also occur on other Nearctic mountains and in the northern taiga. The same spider genera and families dominate arctic and alpine tundra areas on several different continents.
Ground surface spider populations were studied using can traps for 3-1/2 years on sand-pine dunes, pine flat-woods, citrus groves, and residential areas in central Florida. Twenty-three prevalent (0.5 or more percent of total population) species involving, primarily, 6 prevalent (5.0 or more percent of total population) families occurred in distinctive, specifically different, ground surface spider populations in each ecosystem. The sand-pine dune population was 53% lycosid, 19% gnaphosid, and 18% salticid; the pine flat-woods, 64% lycosid, 21% salticid, and 5% linyphiid; the residential area, 54% lycosid, 23% theridiid, and 16% linyphiid; and the citrus grove, 38% clubionid, 19% theridiid, 18% lycosid, and 11% linyphiid. The population in the citrus grove was also only 1/3 as large as those of the other ecosystems. Most of the differences among the populations of the sand-pine dunes, pine flat-woods, and residential areas seemed to be the result of ecologically-equivalent species replacement, but the strikingly different citrus grove population could be the result of repeated soil surface disturbance during cover crop cultivation.
1. Spiders were collected over a period of 6 months by pitfall trapping and absolute density sampling. 2. The numerical species composition of the pitfall trap catch was different to the composition of the spider community as indicated by density sampling. 3. The relationships between pitfall and density catches with time for single species were inconsistent. 4. Sex ratios differed markedly between the pitfall trap catch and those found in the density samples. 5. Possible causes of the failure of pitfall traps to reflect community composition adequately, and the implications for the use of pitfall traps in ecological sampling are discussed in the light of recent literature.
"Measuring Biological Diversity assumes no specialist mathematical knowledge and includes worked examples and links to web-based software. It will be essential reading for all students, researchers, and managers who need to measure biological diversity."--BOOK JACKET.
Spiders were collected from the forest floor surface using pitfall traps (cans and buckets) and funnel traps at 12 study sites selected to represent the sandhill community of north and central Florida. A total of 5236 spiders was collected, which included 23 families, 92 genera, and 154 species. The largest number of individuals (528) was collected at Orange City and the largest number of species (48) was collected at the most northern site, Suwannee River State Park. Species richness, abundance, similarity and seasonal variation were compared among the study sites. Lycosidae comprised 75.2% of the total number of spiders collected. Four species were collected at all 12 sites: the lycosids Lycosa ammophila, Schizocosa duplex, and S. segregata, and the salticid Habrocestum xerophilum. Eighty-three (53.9%) of the 154 species were collected at only one site.
Raised and basin bogs are in serious decline throughout the western Palaearctic. There is a need for a monitoring protocol that would signal changes in the habitat and the biota it supports. Spiders (Araneae) are a group of predators containing many bog specialist species, some of which are of Red Data Book status. Twelve-month continuous trapping in 11 basin bogs in Cheshire (western England) established the species present, their phenology, and relative abundance. Data were combined with those from another 21 lowland bogs obtained from the literature and a number of common statistical descriptors calculated. Some of these were of little value, but the number of spider bog indicator species is shown to be a surrogate for the conservation value of the total invertebrate fauna of bogs in the study area. A model short-survey protocol is devised and tested. Using this protocol and suggested stopping rules, it appears that adequate indication of good peatland sites can be assumed when the naturalness index exceeds 0.5, the species quality index is ⩾1.8, and the indicator species–area relationship gives a datum point on or above the trend line derived from the full data set.
This study, conducted in the Santa Cruz Mountains of California, provides data on the abundance and diversity of litter spiders and other arthropods in three redwood forest conditions: old growth, second growth, and tree farm. Litter spiders are linked to and reflect habitat structure and prey abundance and can act as indicators for redwood forest restoration and monitoring. There were significant declines in spider and other arthropod diversity and abundance with increased logging and decreased herb cover. The absolute and relative increase in nocturnal spiders and detritivores in unlogged sites suggests that guild structures of spiders and other arthropods can indicate forest recovery from logging disturbance. Furthermore, selectively harvested stands do not retain old-growth levels of litter arthropod diversity or abundance. This study identifies potential indicator redwood litter spiders that show higher abundances in old-growth areas, Zelotes sp. (Gnaphosidae), Xysticus sp. (Thomisidae), and Ceratinops inflata (Linyphiidae) and a possible old-growth specialist, Phrurotimpus sp. (Liocranidae). These findings strengthen the case for including soil arthropods in redwood forest monitoring and assessment and for the preservation of undisturbed forest areas.
Epigeic invertebrates such as spiders are of increasing importance for habitat character- ization and for assessments within environmental plannings in Germany and other European countries. Due to high costs for spider sampling (e.g., with pitfall traps), proposals for a limited sampling effort are required for the practical use. The results of a two-year study with continuous sampling are compared to results of short-term sampling and to results of a reduced number of traps. The same data set is used for all evaluations. Decreasing sampling effort generally reduced the number of recorded species and led to a biased ecological characterization of the spider communities. Reducing the number of pitfall traps used provided a more representative sample than did reducing the duration of sampling. In general, errors based on reduced sampling were lower for agricultural than for natural habitats. These results offer practical use of spiders for bioindication in future environmental planning.
International and Canadian national and provincial level policy have proposed the use of criteria and indicators to examine the sustainability of renewable resource management. Species suitable as ecological indicators are those whose biology are sensitive to disturbance and therefore demonstrate a negative effect of management on the processes or functioning of the ecosystem. Ground dwelling invertebrates such as carabid beetles and spiders have strong potential as ecological indicators as they are readily surveyed in sufficient numbers for meaningful conclusions to be drawn, have a stable taxonomy and, at least in the case of ground beetles, are readily identified. They are good local scale indicators of ecosystem disturbance in forested landscapes at both the short and long time scales, responding to both clearcut logging and fire differently. Ground beetles and spiders in boreal Canada may not be good indicators of disturbance at landscape scales, as little response to the creation of forest edges and habitat fragmentation has so far been observed. We propose that these bioindicators be used as part of local-level validation monitoring to test hypotheses about disturbance impacts. In this way, bioindicators are used in a research setting to evaluate silvicultural practices, providing a rating of their sustainability for a given broad forest type grouping.
A considerable number of alternative approaches have been suggested during the last years to predict species richness of a given taxon, while retaining information on the identities of the observed individuals. Such information can be extremely useful for choosing conservation priority areas, either by using raw richness values or, preferentially, by considering the complementarity between potential sites. Among the most popular approaches is the use of indicator taxa. Both one single family and a group of several families are here tested in their ability to predict the number of spider (Araneae) species independently of sampling effort, geographical location and type of habitat. We use data from three Portuguese protected areas as a test case. A two-family indicator group – Gnaphosidae and Theridiidae – is found to be a good surrogate of species richness, even if caution is needed regarding the comparison of sites with considerably different sampling effort or vegetation cover. No single family can be seen as a good surrogate of the totality of spiders. In addition, only a group of the two mentioned families is found to be efficient and reliable either when used to rank sites according to taxa richness or for determining near-minimum sets of sites for conservation. We therefore recommend surrogacy with this indicator group as a promising approach for the prediction of spider species richness or evaluation and ranking of areas according to their conservation importance. The reached conclusions should uphold for Portugal and the entire Mediterranean region.
Summary 1. Invasions by alien plants into unspoiled ecosystems are a cause for concern because the pristine systems are important stores of biodiversity. Indeed, the introduction of non-indigenous species into protected areas is a direct threat to conservation. Consequently, it is fundamental to document the impact that alien invasive plants have on native communities and to determine if, and at what rate, native communities re-establish following the removal of invasives. 2. Chromolaena odorata is one of the most important invader species in the savanna biome in South Africa. It reduces vegetation heterogeneity in grasslands, savannas and forests. 3. Spiders, as ecological indicators for change, were used to investigate the impact of (i) C. odorata invasions, (ii) C. odorata invasion durations, and (iii) the impact of clearing C. odorata on abundance, assemblage patterns, diversity and estimated species richness of spiders. 4. The progressive invasion of C. odorata with increasing invasion duration brings with it changes in native spider abundance, assemblage patterns, diversity and estimated species richness. Native spider assemblages do re-establish after clearing C. odorata without further management intervention. Small lingering differences are observed between the native and the cleared sites, suggesting that other features of the habitat may have been affected by the invasion and clearing. 5. Synthesis and applications . Alien clearance is an essential and invaluable management tool. There are a substantial number of programmes that aim to control alien invasive plants but very little is known about the way in which biodiversity recovers after alien plant removal. Our data show that the removal of alien invasive plants benefits biodiversity with immediate effects, highlighting that management should be carried out to control this invasive, even if the area has been invaded for a long period of time. These data are important for policy-forming and informing policy-makers that alien invasion and removal are critical for biodiversity conservation management.
The classic Jaccard and Sørensen indices of compositional similarity (and other indices that depend upon the same variables) are notoriously sensitive to sample size, especially for assemblages with numerous rare species. Further, because these indices are based solely on presence–absence data, accurate estimators for them are unattainable. We provide a probabilistic derivation for the classic, incidence-based forms of these indices and extend this approach to formulate new Jaccard-type or Sørensen-type indices based on species abundance data. We then propose estimators for these indices that include the effect of unseen shared species, based on either (replicated) incidence- or abundance-based sample data. In sampling simulations, these new estimators prove to be considerably less biased than classic indices when a substantial proportion of species are missing from samples. Based on species-rich empirical datasets, we show how incorporating the effect of unseen shared species not only increases accuracy but also can change the interpretation of results.
In an agroecosystem, catches of epigeal invertebrate predators obtained by pitfall traps were compared to absolute population
densities estimated by ground photoeclectors in two different habitats, a field and an adjacent set-aside land. In general,
abundance of Carabidae and Lycosidae were overestimated by pitfalls, while Staphylinidae and Linyphiidae were underestimated,
and beetle larvae showed no obvious trend. The overestimation of Carabidae and Lycosidae by pitfalls had its maximum in spring
and summer. Numbers collected by pitfalls did represent actual population densities better in the field than in the set-aside.
This is probably caused by the higher vegetation diversity and complexity of the set-aside land which additionally influenced
the catches. Pitfalls recovered higher numbers of animals and species, and species composition differed significantly between
pitfalls and photoeclectors, in the field as well as in the set-aside. Body size seemed to be the main factor in determining
the catch, the relatively larger species being more frequently caught by pitfall traps. In sum, the relationship between pitfall
trap catches and actual population densities appeared to be either absent, weak or highly variable among taxa, habitat and
time of the season. Thus numbers caught in pitfall traps cannot be considered as reliable indices of “real” abundance nor
do they reflect the relative abundance within a given predator community correctly. Therefore, in most cases absolute density
estimates should be preferred for the study of epigeal invertebrates in arable land. However, I suggest a combination of both
pitfall traps and standardised area samples, because the two approaches possibly provide information of different qualities
equally important for the evaluation of epigeal predator species, namely searching activity and population density.
NOTE: This is not a book, contrary to what ResearchGate claims. This is a software application and User's Guide. The current version is Version 9. The citations here are incomplete, since each version has its own citations. EstimateS currently has more than 4000 citations in the peer-reviewed literature. For the full list, go to GoogleScholar: http://bit.ly/11YdUlg .
Spiders collected in southeast Arkansas by the pitfall trap method
- P R Dorris
iNEXT: iNterpolation and EXTrapolation for species diversity. R package version 2.0.19
- T C Hsieh
- K H Ma
- A Chao
A comparison of pitfall trapping and vacuum sampling for assessing spider faunas on heathland at Ashdown Forest, south-east England
- P Merrett
- R Snazell
Spiders collected in Southeast Arkansas using pitfall traps placed in pine-hardwood forests that received various forestry treatments -- A preliminary list
- P R Dorris
- L C Thompson
Behavioural responses of three linyphiid spiders to pitfall traps
- C J Topping
Habitat partitioning by the wolf spider (Araneae, Lycosidae) guild in streamside and riparian vegetation zones of the Conejos River
- J B Morning
- K W Stewart
Aggregations of Sphodros rufipes (Araneae: Atypidae) in an urban forest
- S B Reichling
- C Baker
- C Swatzell