Northeastern Kansas Research Articles

Influence of Abrams M1A1 Main Battle Tank Disturbance on Tallgrass Prairie Plant Community Structure

The Department of Defense's Range and Training Land Assessment program provides information and recommendations to range managers regarding the condition of training lands. This information is used to assist in scheduling training areas and in monitoring the effectiveness of rehabilitation projects. Fort Riley Military Installation is a major training reservation located in the Flint Hills of northeastern Kansas, within the tallgrass prairie ecosystem. A randomized complete block design composed of three treatments (M1A1 Abrams tank traffic during wet and dry soil conditions, and a nontrafficked control) with three replications was established in each of two soil types, a silty clay loam and a silt loam soil, on Fort Riley in 2003. Disturbance was created by driving the tank for five circuits in a figure-eight pattern during either during wet or dry soil conditions. Two additional experimental treatments were added during the study: five additional tank passes on one-half of each figure eight in 2004 and burning in 2006. Two areas, a curve and straightaway, within each traffic intensity (and later, burn treatment) subplot were designated for sampling. Aboveground biomass, species composition, and ground cover were measured during each growing season. Recovery of grass and total aboveground biomass in silty clay loam soil was delayed for curve areas and following disturbance in wet soil conditions, respectively. Species composition and ground cover continued to exhibit significant disturbance effects in 2007, with greatest damage observed for repeated traffic under wet soil conditions. Fire effects on vegetation were variable and generally greater for undisturbed control plots than for disturbed areas. The tallgrass prairie typically is considered to be among the most resilient of military training lands, but our research suggests that resiliency is dependent upon soil type and training conditions, and may require longer periods of recovery than previously thought.

Environmental Correlates of Survival and Reproduction in Old-Field Rodents

We used regression trees to assess seasonal relationships between vital rates (survival and reproduction) and a suite of environmental variables for hispid cotton rats (Sigmodon hispidus) and prairie voles (Microtus ochrogaster). We found only 2 relationships between vital rates and environmental variables for M. ochrogaster, whereas we found relationships in all seasons for S. hispidus. The majority of recovered regression trees contained multiple variables, indicating that the vital rates of S. hispidus were affected by interactions among environmental correlates. Vital rates of S. hispidus were affected most by precipitation, temperature, and snowfall; but the direction of effects of these environmental variables was not consistent among seasons. Our analyses indicate that populations of M. ochrogaster in northeastern Kansas are relatively insensitive to environmental variability, whereas survival and reproduction in S. hispidus are influenced by the environment throughout the year.

Annual fire and mowing alter biomass, depth distribution, and C and N content of roots and soil in tallgrass prairie

Management practices, such as fire and mowing, can affect the distribution and quality of roots and soil C and N in grasslands. We examined long-term (13 years) effects of annual fire and mowing on fine (<2 mm) roots and soil C and N content in a native tallgrass prairie at Konza Prairie Biological Station in northeastern Kansas, USA. Using 90 cm deep soil cores, we determined that fire and mowing independently and interactively influenced the quantity and depth distribution of fine root biomass, root C and N concentration, and soil C and N content. Annual burning increased total fine root biomass by 48% and total C storage in roots by 47% compared to unburned unmowed plots, and resulted in a deeper distribution of roots. There was a significant interaction of fire and mowing, whereby mowing reduced root biomass and root C storage by ~30% in annually burned plots, but did not affect total root biomass in unburned plots. Mowing also resulted in shallower distribution of roots regardless of fire treatment. Root N concentration was reduced by 15–25% in plots that were burned, mowed, or both. Mowing effects on soil C and N were restricted to surface soils (0–10 cm), where mowing reduced soil C concentrations by ~20% and N concentrations by 17% regardless of burning treatment. In contrast, burning alone did not significantly influence soil C and N concentrations. In general, root biomass, root C and N mass, and soil C and N concentrations declined with depth, and most responses to burning and mowing exhibited significant interactions with depth. Different long-term fire and mowing regimes can significantly alter belowground root biomass and C and N dynamics in grasslands, and in particular at depths in the profile that are not typically sampled.

Summer Production of Lettuce, and Microclimate in High Tunnel and Open Field Plots in Kansas

High tunnels have been shown to be a profitable season-extending production tool for many horticultural crops. Production of cool-season vegetables during the hot summer months represents a challenge to market growers in the midwestern United States. Two experiments were conducted to investigate the microclimate and production of eight leaf lettuce (Lactuca sativa) cultivars in high tunnels and open fields, using unshaded and shaded (39% white shadecloth) tunnels in Summer 2002 and 2003, respectively. Wind speed was consistently lower in high tunnels with the sidewalls and endwalls open. An unshaded high tunnel resulted in an increase of daily maximum and minimum air temperatures by ≈0.2 and 0.3 °C, respectively, in comparison with the open field. In contrast, daily maximum air temperature in a shaded high tunnel decreased by 0.4 °C, while the daily minimum air temperature was higher than that in the open field by 0.5 °C. Using high tunnels did not cause a marked change in relative humidity compared with the open field. When using shadecloth, the daily maximum soil temperature was lowered by ≈3.4 °C and the leaf surface temperature was reduced by 1.5 to 2.5 °C. The performance of lettuce during summer trials varied significantly among cultivars. Unshaded high tunnels generally led to more rapid bolting and increased bitterness of lettuce compared with the open field. Lettuce grown in high tunnels covered by shadecloth had a lower bolting rate, but decreased yield relative to the open field. Based on our results, summer lettuce production would not be recommended in high tunnels or open fields in northeastern Kansas, although the potential of shaded high tunnels deserves further studies. Reference crop evapotranspiration (ET0) was estimated from meteorological data on a daily basis using the FAO-56 method. The ET0 was lowest in the shaded high tunnel and was the highest in the open field. Relatively lower ET0 in high tunnels indicated a likely lower water requirement and therefore improved water use efficiency compared with the open field.

(U–Th)/He dating of kimberlites—A case study from north-eastern Kansas

Dating kimberlite intrusive rocks by radiogenic isotope geochronology often is a difficult task, complicated by both the lack of dateable minerals within kimberlite as well as significant sample alteration that can degrade samples and alter parent–daughter ratios. This study presents a new geochronologic tool for timing the emplacement of kimberlites using the (U–Th)/He system to date the cooling of common kimberlite phenocrystic and xenocrystic minerals. To demonstrate the use of this technique, new apatite, titanite, zircon, magnetite and garnet (U–Th)/He ages constrain the timing of emplacement for the Stockdale, Tuttle, Baldwin Creek, Bala, and Leonardville kimberlite pipes, located in Riley County, Kansas. Zircon from the Tuttle pipe and titanite from the Stockdale pipe yield (U–Th)/He ages of 108.6 ± 9.6 Ma and 106.4 ± 3.1 Ma, respectively. These data are consistent with new Tuttle kimberlite Rb–Sr analyses of phlogopite megacrysts that give a five point isochron age of 106.6 ± 1.0 Ma. Similarly, an apatite (U–Th)/He age of 85.3 ± 2.3 Ma from the Baldwin Creek kimberlite is in agreement with a Rb–Sr phlogopite age of 88.4 ± 2.7 Ma. These dates demonstrate that (U–Th)/He thermochronometry provides reliable timing constraints on the cooling of common kimberlite xenocrystic phases, thereby timing kimberlite emplacement. In addition to the use of more commonly used apatite and zircon (U–Th)/He thermochronometers, we produced reliable emplacement ages of 103.0 ± 7.5 Ma for the Bala kimberlite using (U–Th)/He dating of phenocrystic magnetite and an age of 98.8 ± 8.9 Ma for the Tuttle kimberlite using (U–Th)/He dating of megacrystic garnet. In contrast, kimberlitic apatite (U–Th)/He ages from the Stockdale, Bala, Tuttle, and Leonardville kimberlites yield ages ranging from 67.3 ± 4.4 Ma to 64.3 ± 5.6 Ma, suggesting a local, possibly hydrothermal reheating event resulting in resetting of the apatite (U–Th)/He clock in latest Cretaceous to earliest Tertiary time. Additional (U–Th)/He analyses of apatite from nearby sandstone and basement rocks suggest regional cooling below ~ 70 °C at ~ 165 Ma. These (U–Th)/He and Rb–Sr age data imply that the kimberlites were emplaced over a period of time from ~ 85–110 Ma with several pipes subjected to local reheating at ~ 65 Ma.

Reappearance of the large polypore mushroom, Bondarzewia berkeleyi, in northeastern Kansas

A period of rainy weather in the vicinity of Lawrence, Douglas County, Kansas during the last week of June 2007 facilitated the emergence of a diversity of mushroom species. In early July, a resident of North Lawrence noticed an unusual, white, amorphous mushroom with several finger-like growths on the ground next to a white oak tree (Quercus alba) on his property. On 6 July, the first author visited the site and collected the mushroom which had transformed into an erect, fan-shaped growth with several lobes approximately 12 inches high and 24 inches wide. The mushroom weighed 15 pounds (Fig. 1). The second author identified the specimen as Bondarzewia berkeleyi (Fr.) Bond. et Sing.. Another fruiting body of this species appeared toward the end of June 2008 at the same location on the opposite side of the white oak tree. By the end of July, the mushroom had grown to a total width of 36 inches.

The giant resin bee making its way west: First record in Kansas (Hymenoptera: Megachilidae)

The invasive giant resin bee (Megachile sculpturalis Smith) was first discovered in North America in 1994. A 2005 study provided the first predictive ecological niche model for any bee species and concluded that M. sculpturalis, then confined to the eastern United States, would eventually spread as far south as southern Florida, as far north as southern Ontario and Nova Scotia, and as far west as South Dakota, western Kansas, and northwestern Texas. Herein I provide the first record of M. sculpturalis from northeastern Kansas, documenting that the species has indeed continued its westward expansion in North America and the new available records entirely correspond to the earlier predictions.

Influence of Woody Vegetation on Small Mammals in Tallgrass Prairie

We examined response of small mammals to woody invasion of tallgrass prairie in northeastern Kansas by sampling sites that ranged from 0 to 100% in woody cover (i.e., frequently burned prairie to unburned closed-canopy gallery forest; woody coverage mapped from satellite imagery). Abundance and biomass of small mammals initially increased with increasing woody vegetation, but then decreased to their lowest level at 100% woody cover. Richness was greatest (an average of seven species) where woody cover was ≤17% and decreased to one species where woody cover was 100%. Abundance of white-footed mice (Peromyscus leucopus) increased as woody cover increased from 0 to 62% cover, but decreased in forested sites (100% cover). Abundance of western harvest mice (Reithrodontomys megalotis) decreased as woody cover increased; they were not recorded in forested sites. Deer mice (P. maniculatus) were present in sites with no to low levels of woody vegetation, but were absent in sites with moderate to high levels of woody cover. The 11 species captured were recorded in sites that had little woody vegetation (≤17% cover), whereas only seven species were captured at sites where considerable woody vegetation (≥28% cover) occurred. Even white-footed mice and eastern woodrats, which are considered woodland forms, decreased in abundance or were absent from forested sites. Overall, the results demonstrate that even relatively small amounts of woody vegetation in prairie landscapes can alter abundance, biomass and species richness and composition of small mammal communities.

Glacial striae and ice-push deformation as indicators of glacial directional movement in northeastern Kansas

There are several indicators of directional properties in sedimentary beds that geologists use including intensity and size, which decrease away from the source; roundness, which increases from source; and cross-beds dip away from the source. Ice-push features likewise give a direction of origin, but glacial striae ar a directio al property that does not indicate unique direction or an origin. In the situation of glacial striae in Kansas, however, the direction can be safely determined k owi g from where the glaciers came.

Observation of aberrant growth in a Timber rattlesnake (Crotalus horridus)

In Crotalus horridus, a species in need of conservation in Kansas (Brown 1993), growth is generally positively correlated with the number of rattle segments, in accordance with the frequency of ecdysis. In compiling 17 years (1990-2006) of timber rattlesnake morphologic data from a population in northeastern Kansas, Fitch and Pisani (2006) noted that, among males, snakes whose snoutvent length (SVL) fell within the range of 628-720mm (mean = 675.2mm) typically exhibited a button and 3 additional rattle segments. An overlap in this range is seen with individuals bearing a button plus 2, 4, 5 or, at most, 6 segments in a rattle that normally would show appreciable distal taper. Therefore, the collection of an anomalous male snake (Fig. 1) from northeastern KS weighing 199.5g, with a SVL of 668mm and an incomplete string of 18 rattle segments in May of 2007 was unexpected. Predictably, aside from the terminal segments, the rattle was not markedly tapered (see Table 1 below), an indication that growth did not accompany the addition of new segments beyond the fourth or fifth shed. This period is typically when the most significant (p=0.95) gains are made in the growth of northeast Kansas timber rattlesnakes (Fitch and Pisani 2006). The high correlation between segment width and incremental growth of rattlesnakes is well-documented (Fitch and Pisani 1993; Klauber 1956).

Variation in Vigilance in White-tailed Deer (Odocoileus Virginianus) in Northeastern Kansas

This study was designed to test hypotheses regarding vigilance (a state of alertness that allows an animal to detect the presence of predators or other threats) in white-tailed deer (Odocoileus virginianus). Based on findings on other species, we predicted that: (1) increasing group size would result in decreased individual vigilance; (2) juveniles would be less vigilant than adults; and (3) males would be less vigilant than females. Deer were observed from a tower in northeastern Kansas from May through Jul. 2001 at dawn and dusk. In accordance with other species, individual vigilance was negatively correlated with group size and juveniles spent less time vigilant than adults. However, there was no apparent difference in vigilance levels between the sexes in adults. We conclude that deer exploit loose aggregations to maximize foraging time by decreasing individual vigilance (without increasing risk) and that the trade off between vigilance and foraging intensity changes with maturation.

The influence of trap density and sampling duration on the detection of small mammal species richness

Assessing species richness of small mammal communities is an important research objective for many live-trapping studies designed to assess or monitor biological diversity. We tested the effectiveness and efficiency of various trap densities for determining estimates and counts of small mammal species richness. Trapping was conducted in grassland habitats in northeastern Kansas during spring and fall of 2002 and 2003. Estimates and counts of species richness were higher at increased trap densities. This effect appeared to be primarily due to the higher number of individuals sampled at higher trap densities. At least 3 nights duration was needed to produce a stable estimate of species richness for the range of trap densities tested (9–144 trap stations/ha). Higher trap densities generally reached stable richness estimates in fewer nights than low density trapping arrangements. Given that counts and estimates of species richness were influenced by trap density and sampling duration, it is critical that these parameters are selected to most effectively meet research objectives.

Reconstructing Late Cenozoic Stream Gradients from High-Level Chert Gravels in Central Eastern Kansas

Interpreting the evolution of Kansas' landscape east of the Flint Hills provides major challenges. In the Neogene (late Tertiary) and perhaps part of the Pleistocene, streams transported a variety of sedimentary materials, including chert gravels derived from the Flint Hills. Gentle intermittent uplift stimulated the stream system to cut down, locally removing and reworking the gravels to create stream-terrace deposits that consist mostly of chert pebbles, which now lie well above the floodplains of modern streams. By correlating the elevations of these gravels, the gradients of the trunk streams that deposited them can be reconstructed. Interestingly, these ancient streams flowed southeast at a little more than a foot per mile (0.2 m/km), roughly the same as the gradient of the trunk streams in the region today.&#x0D; The evolving landscape in eastern Kansas also has been strongly influenced by an extensive network of fractures that is widespread in the midcontinent region and may be worldwide in extent. In northeastern Kansas, glaciation during the Pleistocene disrupted the southeasterly drainage and established the present location of the Kansas River. South of the Kansas River and its immediate tributaries, however, the general southeasterly drainage has been preserved.&#x0D; We have made use of the wealth of topographic-elevation data now available in digital form known as DEMs or digital elevation models. Coupled with GIS procedures, the DEMs helped link the mapped distribution of chert gravels with hypothetical fitted surfaces that represent ancient stream gradients. Furthermore, DEM data placed in shaded-relief map form emphasize the influence of fractures in evolution of the drainage system.&#x0D;

Restoration of Prairie Community Structure and Ecosystem Function in an Abandoned Hayfield: A Sowing Experiment

AbstractUsing a multispecies seed sowing experiment, we investigated the roles of seed and microsite limitation in constraining the restoration of native prairie diversity and ecosystem function in an abandoned upland hayfield in northeastern Kansas. Seeds of 32 native and naturalized plant species from the regional pool were sown into undisturbed and experimentally disturbed field plots. After six growing seasons, experimental sowing led to major shifts in species and functional group composition, increases in native species abundance and floristic quality, declines in abundance of non‐native species, and increases in plant diversity. These changes in community structure led to significant changes at the ecosystem level including increases in light capture, peak biomass, primary production, litter biomass, root biomass, and C storage in roots. Our findings reveal the importance of seed limitations in constraining the natural recovery of prairie vegetation, biodiversity, and ecosystem functioning in this grassland and confirm broadcast sowing as a useful tool for the restoration of upland hayfield sites.

Density‐dependent recruitment in grassland small mammals

1. Density dependence has an important influence on the dynamics of many species of small mammals. To regulate population growth, density must affect negatively a vital rate (e.g. fecundity); however, little is known about which vital rates are most affected by density. 2. We used a long-term data set for five species of rodents from north-eastern Kansas, USA to test for relationships between density and the proportion of pregnant females, per capita fecundity and recruitment. We estimated proportion of pregnant females using data collected in the field and fecundity using data on survival, proportion of pregnant females and literature-based density-dependent litter size for each species. We used reverse capture histories to estimate per-capita recruitment. 3. The proportion of pregnant females was related positively to density in most species. Fecundity was related negatively to density in the cotton rat (Sigmodon hispidus Say & Ord, 1825) and not related to density in the four remaining species. Recruitment was related negatively to density in all five species, although not all relationships were statistically significant. 4. The signature of density-dependent recruitment was strongest in the prairie vole [Microtus ochrogaster (Wagner, 1842)] and cotton rat and less so in the remaining species. 5. Our analyses indicate that density affects recruitment negatively in grassland small mammals either through a reduction in immigration or reduced survival of nestlings. Models that seek to include empirical estimates of density dependence may need to include immigration in addition to survival and fecundity.

The spider genus Arachosia (Araneae: Anyphaenidae): A new addition to the Kansas fauna

The hunting spider genus Arachosia O.P. Cambridge 1882 (Araneae: Anyphaenidae) is represented in the United States by one species, A. cubana (Banks 1909; Fig. 1), which formerly resided in the genus Oxysoma Nicolet 1849 (Ramirez 2003). The fifteen other species in the genus occur in Central and South America (Platnick 2007). A. cubana was originally described by Banks (1909) from specimens collected in Cuba. In the United States, it has been reported from Arizona, Arkansas, Florida, North Carolina, Massachusetts (Platnick 1974), Pennsylvania (NatureServe 2006), Virginia (Young and Edwards 1990), Illinois, Ohio and Michigan (Sierwald et al. 2005). Field work by the author in northeastern Kansas has uncovered the presence of A. cubana in Douglas County.

H2-rich and Hydrocarbon Gas Recovered in a Deep Precambrian Well in Northeastern Kansas

In late 2005 and early 2006, the WTW Operating, LLC (W.T.W. Oil Co., Inc.) #1 Wilson well (T.D. = 5772 ft; 1759.3 m) was drilled for 1826 ft (556.6 m) into Precambrian basement underlying the Forest City Basin in northeastern Kansas. Approximately 4500 of the 380,000 wells drilled in Kansas penetrate Precambrian basement. Except for two previous wells drilled into the arkoses and basalts of the 1.1-Ga Midcontinent Rift and another well drilled in 1929 in basement on the Nemaha Uplift east of the Midcontinent Rift, this well represents the deepest penetration into basement rocks in the state to date. Granite is the typical lithology observed in wells that penetrate the Precambrian in the northern Midcontinent. Although no cores were taken to definitively identify lithologies, well cuttings and petrophysical logs indicate that this well encountered basement metamorphic rocks consisting of schist, gneiss, and amphibolitic gneiss, all cut by aplite dikes. The well was cased and perforated in the Precambrian, and then acidized. After several days of swabbing operations, the well produced shows of low-Btu gas, dominated by the non-flammable component gases of nitrogen (20%), carbon dioxide (43%), and helium (1%). Combustible components include methane (26%), hydrogen (10%), and higher molecular-weight hydrocarbons (1%). Although Coveney and others [Am. Assoc. Petroleum Geologists Bull., v. 71, no, 1, p. 39–48, 1987] identified H2-rich gas in two wells located close to the Midcontinent Rift in eastern Kansas, this study indicates that high levels of H2 may be a more widespread phenomenon than previously thought. Unlike previous results, the gases in this study have a significant component of hydrocarbon gas, as well as H2, N2, and CO2. Although redox reactions between iron-bearing minerals and groundwater are a possible source of H2 in the Precambrian basement rocks, the hydrocarbon gas does not exhibit the characteristics typically associated with proposed abiogenic hydrocarbon gases from Precambrian Shield sites in Canada, Finland, and South Africa. Compositional and isotopic signatures for gas from the #1 Wilson well are consistent with a predominantly thermogenic origin, with possible mixing with a component of microbial gas. Given the geologic history of uplift and rifting this region, and the major fracture systems present in the basement, this hydrocarbon gas likely migrated from source rocks and reservoirs in the overlying Paleozoic sediments and is not evidence for abiogenic hydrocarbons generated in situ in the Precambrian basement.

Paleoenvironmental interpretation of multiple soil–loess sequence at Milford Reservoir, northeastern Kansas

Abstract A loess/soil section near the Republican River in northeastern Kansas includes three superposed soils/paleosols in at least three superposed loess units, including Peoria Loess (PL), the Gilman Canyon Formation (GCF), and Loveland Loess (LL), The GCF coincides with a composite soil with a 1.3 m thick, buried organic-rich (A) horizon that yields AMS radiocarbon ages from 30.3 to 22.4 ka (or 35.7 to 26.9 ka when calibrated) that overlies a 1.6 m oxidized B horizon complex. The B subhorizons stratigraphically and morphologically resemble the “reddish pedocomplex” described elsewhere in Kansas and Illinois that dates between about 69 and 35 ka. The upper LL yields a TL age of about 136 and 130 + 30 ka. Thus, PL, the GCF, and LL were probably deposited mainly during the late Wisconsinan, middle Wisconsinan, and Illinoian (∼ Oxygen Isotope Stages (OIS) 2, 3, and 6, or about 12 to 24, 24 to 60, and 130 to 188 ka, respectively). Soils 1, 2, and 3, then formed mainly during OIS stages 1, 3, and 5, respectively, or about 12 to 12, 60 to 60, and 73 to 130 ka. In comparison with other dated stratigraphic sections in the Great Plains, soils/paleosols have relatively simple, cumulic horizon sequences, as is typical at sites distal from principle loess source regions. Nonetheless, they record a complex pedosedimentary history that reflects climatically-driven variations in rates of sedimentation and pedogenesis. Soil 1 is an Udic Argiustoll with 21-cm A (mollic)/69-cm Bt (argillic)/60-cm Bk horizons, that formed under modern-type grassland and climate. Soil 3, the Sangamon paleosol, includes a 3-m thick, highly rubified and clay-rich argillic horizon that, based on its morphological properties, probably formed under a relatively warm, moist, equable climate and deciduous-type forest. Soil 2 coincides with the GCF, and as such is a pedolithostratigraphic unit that includes a 1.3-m mollic horizon and to 1.6-m oxidized 3Btb and 3BCb horizons. Whereas the oxidized B horizons apparently represent relatively warm, moist climatic conditions between about 65 to 35 ka, the upper cumulic (mollic) A horizons of the GCF probably formed under progressively cooling climate and grassland between about 35.7 and 26.9 (calibrated radiocarbon) ka. Estimated mean accumulation rates (MARs) of loess range from 0.12 m/k yr for the GCF to about 0.5 m/k yr for PL.

A “Cyclops” of the Bee Lasioglossum (Dialictus) bruneri (Hymenoptera: Halictidae)

This note reports striking morphological aberrations of the compound eye, vertex and ocelli of a bee belonging to the genus Lasioglossum. Morphological aberrations of various kinds occur throughout the bees. Mitchell (1929), Michener (1943), Sivik (1962), Knerer and Atwood (1964), Wcislo et al. (2004), and Engel (2007) have reported sex anomalies, true gynandromorphs, antennal anomalies and metanotal anomalies. These reported aberrations primarily include changes in antennae, shape of the metasoma, genitalic structures, pollen collecting structures and the metanotum. Salt (1927) described the many external and internal changes in aculeate Hymenoptera caused by strepsipterous parasitism. Outside of Hymenopterans, Byers (1992) gave an account of distinct deformities of the head of a single individual of the scorpionfly Panorpa helena Byers, which had only a single normal compound eye and a single antenna both located on the right side of the head. However, no such dramatic aberrations of the head have previously been reported in bees. The ‘‘cyclops’’ bee described here, identified as a female of Lasioglossum (Dialictus) bruneri (Crawford), is therefore of some interest. I collected this unusual specimen on 13 July 2005 during a study conducted along roadsides in northeastern Kansas. The specimen was collected between the hours of 10:15 and 13:15 in a florescent yellow 16 oz. pan trap raised 70 cm above the ground, in the right-of-way along Highway 177 south of Cottonwood Falls in Chase County, Kansas. The most abundant forb in bloom in the area was Dalea purpurea Vent. (Fabaceae), with Ruellia humilis Nutt. (Acanthaceae), Dalea candida Michx. ex Willd. (Fabaceae), Amorpha canescens Pursh (Fabaceae) and Desmodium illinoense Gray (Fabaceae) present in smaller numbers. Land adjacent to the right-of-way was primarily rangeland grazed by cattle. Numerous Lasioglossum (Dialictus) spp. individuals were collected at this site prior to and after the collection of this specimen, although this individual was the only L. bruneri collected, and the only abnormal individual. The bee will be deposited in the Snow Entomological Collection, Division of Entomology, University of Kansas Natural History Museum, with the label J.L. Hopwood 2006 voucher. The bee has morphological aberrations of the head conspicuous enough to be seen without the aid of a microscope (Figs. 1–3). The size of the head is 75% of that of a typical specimen, with head width particularly reduced. Most readily noticeable is the fusion of the compound eyes at the vertex, which somewhat resembles the holoptic condition of honey bee drones and other insects such as syrphid flies, but instead results in a continuous, single compound eye (Fig. 1). This single compound eye extends completely over the vertex from either side of the head; thus a true vertex is lost and the ocelli are displaced. The remaining vertex is uniquely sculptured, with striations extending from the midline away from the occipital carina, along the gena (Fig. 2). The ocelli, normally located on the vertex, are situated on the frons just above the antennae. The sizes of the ocelli are highly reduced, as is the interocellar distance, and the ocelli are surrounded by an unusual and strong carina (Fig. 3). There are no other evident deformities of this individual. The mesosoma, wings, legs and metasoma are typical in appearance, with the exception of the presence of a female strepsipteran under the fourth tergum of the metasoma. While the morphological alterations of the head described above cannot definitively be attributed to stylopization, a noticeable decrease in head size has been described as an effect of stylopization (Salt, 1927). An extreme reduction in head size could account for the fusion of the compound eyes and the subsequent alteration of the vertex and ocelli. In any case, this individual has deformities 1 Current address: 33 Bessey Hall, Iowa State University, Ames, IA 50010, e-mail address:

SPATIAL VARIATION IN PREDATION ATTEMPTS ON ARTIFICIAL SNAKES IN A FIRE-DISTURBED TALLGRASS PRAIRIE

The tallgrass prairie historically burned every 2 to 3 y, removing the litter layer and leaving post-burn environments inhospitable to many terrestrial species. Selection pressures, such as lack of food and shelter and increased predation, are intensified for some species over limited time periods. To quantify predation pressures on large snakes, artificial snakes were placed in recently burned and long-term unburned areas of a grassland system in northeastern Kansas. Any disturbance to the original placement of the model snake was considered a predation attempt. Statistical models were used to estimate daily survival rates of individual artificial snakes within both habitat types. A group effect (burned vs. unburned) was selected as the single top model, garnishing >93% of the support for the data. Survival estimates from this top model indicated artificial snakes in newly burned areas had significantly lower daily survival than those placed within unburned sites. Indirect evidence from destroyed artificial snakes indicated raptors were a major predator on large snakes. Overall herpetofaunal activity in burned areas was low during the first 20 d post-burn, with increasing activity throughout the rest of the season. However, activity within unburned areas was constant throughout the spring. Burning tallgrass prairie likely increases predation pressure on large snakes in the area for 1 to 2 mo following the burn due to the lack of cover against aerial predators.