There were 23 crop points, 32 herbaceous points, 30 riparian points, and 28 wood points. Only 2 of the 113 points had no birds (NONE) recorded in the 10-minute period. These were points 103 herbaceous, and 139 crop. Also, there were four instances where counts were discontinued due to the weather, three times because of rain and once because of high winds exceeding 12 mph.

The month of June was extremely wet which may have contributed to the fewer records. Groups of juvenile red-winged blackbirds didn’t start showing up until very late June and early July. Last year, these large groups of fledged blackbirds were obvious by mid-June. The Henslow’s sparrow (HESP) numbers were also down from last year, appearing on 5 points as opposed to last year’s 10 points. The points were in the northern third of the Refuge with one point (point 40) from within the bison confinement. On the 13^th of July, while walking out of a field near point 12, I observed 2 separate groups of fledged Henslow’s sparrows. The first group was 3 fledglings with an adult and the second was 2 fledglings with an adult.

Upland sandpipers (UPSA), another grassland bird of special interest, were not recorded this year although individuals were identified in fields near Highway 163 while traveling between points.

Broods of ring-necked pheasants were small and much scarcer than last year. The heavy rains of late May and early June had an impact on their reproduction as well. However, several adult hens and roosters were observed and so one can expect the hens to make a second or even third attempt at laying another clutch.

There was one new species to have been recorded on the counts this year, the Pileated woodpecker (PIWO). Also notable is the increase in Eastern bluebirds (EABL) on the Refuge. Several broods were recorded or observed this summer. In the case of point 36, the fledglings were still sitting with both adults on the branch near the nesting cavity.

The wet weather was likely the main contributor to the decrease in bird numbers this year as opposed to last year’s dry summer.

REFERENCE:

Thomas, Liessa H., E. E. Klaas. Breeding Birds of a Large-Scale Tallgrass Prairie Restoration in Iowa: Monitoring Abundance and Frequency of Occurrence. Master’s Thesis, Iowa State University, Ames. 1999.

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Anabat Survey Report

Principal Investigator: Kim Livengood

In early May 2004, one evening of active bat monitoring on the Neal Smith NWR was conducted using Anabat bat detectors. This limited survey of a savanna area revealed a species assemblage including Eastern Red bats Lasiurus borealis, Big Brown bats Eptesicus fuscus and many recordings of 40 kHz Myotis. In central Iowa, the endangered Indiana bat and the Little Brown bat are two Myotis species that are difficult to distinguish acoustically. For this reason, calls of these two species are sometimes grouped together and referred to as 40 kHz Myotis calls. According to surveys conducted in 1997 by the Refuge staff, reproductively active Indiana bats are known from the Neal Smith NWR (Photo 1). This survey used active monitoring which means that bat calls were recorded while observations of behavior were made visually. The combination of visual cues and acoustic records improves the chance of identifying bats such as these, which are hard to identify acoustically. A careful analysis of the recorded calls, in the context of the visual observations, led us to conclude that at least some of the 40 kHz Myotis we recorded were Indiana bats. Further acoustic recordings, and preferably trapping, would be necessary to confirm their presence.

The use of bat detectors in this brief survey illustrates the usefulness of this technology (Photo 2). Bat detectors give land managers a cost effective tool to survey bats which are otherwise extremely labor intensive to monitor. They also allow managers to confirm the presence of a bat species without physical interference. This is particularly valuable in areas where maternity colonies are present since care must be taken not to disturb the roosts or stress the females.

Bat detectors can be used in a variety of ways. Active monitoring is the most effective method for species identification, when conducted by a skilled observer. Using this method, observations of bat behavior can be used in conjunction with characteristics of recorded calls to identify a higher percent of calls and to increase the certainty of identification.

Passive monitoring is conducted by leaving bat detectors out in the field to automatically record and store bat calls. This method can be used to record for just a few hours, or all night, every night for years, depending on the objectives. Long-term passive recording has the advantage that the sampling effort can be vastly greater for much less human resource commitment than is possible using active monitoring. This increases the possibility of detecting rare or difficult-to-identify species by increasing the likelihood that distinctive calls from those species will be detected. In addition, the long term record can provide insights into spatial and temporal heterogeneity which are unattainable through other means. This approach is relatively new and there is a great deal yet to be learned about how to get the most out of passively recorded datasets, but the technology has proven effective and relatively inexpensive. If used appropriately, a small network of passive monitoring stations could provide useful baseline data, and provide the means to assess the long-term impacts of land management decisions on bat faunas.

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Integrated Monitoring of Soils, Hydrology, and Vegetation Across a Landscape During Prairie Reconstruction.

Investigators: Cynthia Cambardella¹, Pauline Drobney², Keith Schilling³, Mark Tomer¹, Peter Jacobson⁴

1- Soil Scientists, USDA/ARS NSTL, 2150 Pammel Dr. Ames IA

2- USDI/FWS NSNWR, Prairie City IA

3- IDNR/GSB, Iowa City IA

4- Dept of Biology, Grinnell College, Grinnell IA

This was the establishment year of a long-term project that will evaluate changes in soils and hydrology during the development of a community of native prairie vegetation. Current work is focused on linking landscape-scale C and hydrologic cycles to groundwater nitrate-N and DOC for a small (12 ha) hydrologic catchment area within a new prairie reconstruction site which was seeded in the fall of 2003. The area was surveyed with a differential GPS system to obtain detailed topographic data, which were used to construct a 2-m digital elevation model of the site. Terrain analyses were performed to evaluate hydrologic flowpaths, slopes, and contributing areas across the site. This information was used to locate a series of 15 monitoring transects along hillslopes, plus two more across runoff drainageways. Neutron-probe access tubes were installed along these transects to allow repeated measurements of soil moisture. Runoff collectors were installed to document areas of runoff generation on the landscape. Suction cup lysimeters were installed at 2.4-m depth (above the watertable) to allow water samples to be collected from the unsaturated zone for analyses of nutrients, dissolved carbon, and other inorganic constituents. Initial measurements have been made of soil moisture, runoff, and soil water chemistry, although results are not yet available at the time of reporting.

In December 2003 (prior to grass seeding) and November 2004, we collected 3 soil cores from each sampling site for a total of 294 cores to a depth of 15 cm. The surface soil cores were sectioned into 2 depth increments (0-7.5 and 7.5-15 cm) and soil was composited by depth increment prior to processing for biological and chemical analysis. Measurements for each depth increment from the deep cores will include bulk density, field moisture content, total soil organic C, total soil inorganic C, and soil texture. The surface soil depth increments will be used for analysis of several forms of biologically-active soil C and stabilized soil C in addition to the measurements described for the deep cores. All soil samples will be catalogued and archived at the National Soils Tilth Lab for future experimental purposes.

Four plant monitoring transects were installed adjacent to soil sampling transects in 2004, following the Floristic Quality Assessment Technique (Wilhelm, 1999). Changes in native species diversity and conservatism, exotic species composition, and vegetative cover will be analyzed relative to soil and water characteristics through time.

Tim Weisbrod, a graduate student at the University of Iowa as part of his MS thesis project, conducted a natural gradient bromide tracer test and slug tests to estimate hydraulic conductivity (K) values at the Cabbage site. Six wells were installed in a linear transect along the southern waterway to facilitate tracer injection and monitoring (Photo 3).

The final step of Tim’s MS thesis will be to use the collected data to create a numerical groundwater model. The numerical model will be created using the Groundwater Modeling System (GMS) program, with use of the MODFLOW and MT3DMS codes. The basic geologic and hydrologic understanding established from core descriptions, tracer tests, and slug tests will be used to assign boundary conditions and layer properties at the Cabbage site. The calibrated model will be used to predict future water level changes and nitrate changes through time with varying land use (Photo 4 and Photo 5).

Results of this project will allow us to evaluate how prairie reconstruction effects, and is affected by, changes in soil quality and hydrologic conditions occurring during the transition from agricultural production to a reconstructed prairie. This information is of interest to a diverse group in the scientific community, particularly those with an interest in movement and cycling of water, nutrients, and carbon on the landscape and spatial patterns that are influenced by this movement and cycling. Results will also help USFWS staff evaluate long term effects of investments in prairie reconstruction at NSNWR.

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Effects of Channel Incision on Riparian Zone Hydrology and Sedge Meadow Reconstruction

Principal Investigator: Keith E. Schilling, Iowa Geological Survey, 109 Trowbridge Hall, Iowa City, IA and Pauline M. Drobney, Neal Smith National Wildlife Refuge, P.O. Box 399, Prairie City, IA

Incised channels are common features in many agricultural watersheds with riparian zones often dominated by reed canary grass (Phalaris arundinacea) monocultures. We are exploring how channel incision has modified the water table configuration in the floodplain where we are converting a dense reed canary grass area to a moderately diverse sedge meadow at the Neal Smith National Wildlife Refuge. We designated one side of Walnut Creek for treatment and the other as a control and established plant and monitoring well transects to monitor changing hydrologic conditions relative to floristic composition. We observed that channel incision has lowered the water table from the stream edge to a distance of 30 m into the floodplain, resulting in a large unsaturated zone in the near-stream riparian zone. Continuous water level monitoring during high flow events indicated little interaction of surface water and ground water in a narrow streambank zone adjacent to the channel. Chemical monitoring during 2003 recharge events implied that significant nitrate mineralization had occurred in the unsaturated near-stream riparian zone. Burning, mowing and herbicide treatment during the growing season of 2002 and 2003 effectively removed most reed canary grass on the control side. We observed water tables on the untreated side as much as 1.2 m lower than the treated side due to the effects of plant transpiration (Photo 6). In 2004, data from plant transects installed in the treatment area indicated marked increases in native species diversity and density compared to past years and to the control area. To a large degree, native plant species diversity and density expressed in 2004 was apparently due to propagules within the seed bank, though approximately 2,000 greenhouse grown plants were introduced in fall, 2003, and spring, 2004. In fall, 2003, three areas approximately 10 feet in diameter were concentrated with fen plant plugs taken from an off-refuge area that was undergoing hydrologic repair. A diverse prairie seed mix was introduced in mid-summer, 2004. While monitoring remains ongoing, study results identify the large role that incised streams play in modifying riparian zone hydrology that can subsequently impact ecological restoration in a riparian zone (Photo 7).

Oak savanna research at Neal Smith National Wildlife Refuge: Hydrologic Response of Degraded Oak Savannas to Restoration Treatments

Principal Investigator: Heidi Asbjornsen, Iowa State University

Brief background: Research on savanna restoration was initiated at the Neal Smith National Wildlife Refuge in 2003 as a collaborative project with Iowa State University (see Research Summary submitted in 2003 for more detailed background information). The study includes two remnant savanna sites (approximately 15-20 ha each; “Birdhead” and “Old Game Farm”) that are characterized by large, open-grown white oak and burr oak trees (indicative of former savanna habitat), which as a result of fire suppression have become overgrown with shade tolerant tree species (e.g., ironwood, elm, ash, dogwood). The primary objective of the research is to understand the changes in plant species composition and ecological functioning in response to the restoration treatments. In particular, we are interested in understanding how interactions between the trees and the understory herbaceous vegetation in restored and degraded savanna ecosystems regulate the cycling of water and nutrients through the system. The results of this research will help inform future restoration work, both at the Refuge and at other sites in the Midwest.

Restoration treatments: Mechanical removal of all non-savanna tree species (i.e., everything except for white and bur oak) was conducted in the treatment area at “Old Game Farm” during the winter of 2003-4. Burning was scheduled to occur during the fall of 2004, but was postponed due to inadequate fuel availability.

Plant species composition: Plant species in the herbaceous layer were recorded within the treatment and control areas three times during the growing season (April, July, September). Shrubs were sampled once during the growing season (July).

Hydrology: One groundwater well with a transducer was installed in the treatment and in the control site. Soil moisture access tubes were installed at 4 points surrounding 6 large oak trees (3/treatment) and every 20 m along the two main transects (displaced by 2 m from the center line). Soil moisture monitoring was initiated in August-September but then terminated in October due to a failure in the neutron probe equipment.

Plant water cycling: Plant transpiration was measured for dominant species in the understory of both the treated and control sites, as well as for corn and prairie plants in the adjacent crop field and reconstructed prairie, respectively. Sap flow equipment (thermal dissipation probes) was installed in 6 bur oak trees and 4 subdominant elm trees within the savanna restoration study site, and sap flow monitoring initiated in July.

Oak regeneration: To determine the effects of savanna restoration on oak regeneration, naturally occurring bur oak seedlings are monitored at the treatment and control sites savanna sites. In 2003, plots were established in two landscape positions: below bur oak tree canopy and in canopy gaps. This allowed us to determine where seedlings naturally most densely occur, as well as the importance of canopy gaps for their survival and growth. 2004’s work involved remonitoring all seedlings identified in 2003 for height and basal diameter, as well as adding any newly established seedlings to the study.

Collaboration: Research collaborators on this project include Drs. Cindy Cambardella and Mark Tomer (USDA National Soil Tilth Lab), Dr. Keith Schilling (Geologic Survey Bureau, Iowa DNR) and Dr. Cathy Mabry (ISU, NREM). Two graduate students (Lars Brudvig, Ph.D. candidate, NREM/EEB, and Martin Gomez, Ph.D. candidate, NREM) are currently participating in this research. Two other graduate students also involved in this research completed their degrees in 2004 (Chris Evans, M.Sc., NREM and Holly Karnitz, M.Sc., NREM/EEB). Additionally, we are collaborating with the U.S. Forest Service on a project aimed at assessing ecological indicators used in the USFS Forest Inventory Analysis system.

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Agroecosystem Restoration Research at Neal Smith National Wildlife Refuge:

Integration of Water, Nutrient and Carbon Cycling Under Diverse Annual-perennial Plant

Communities in Agricultural Landscapes

Principal Investigator: Heidi Asbjornsen, Iowa State University

Brief Background: This is a new project initiated in August 2004 with support from the U.S. Forest Service and the Leopold Center, focusing on understanding the effects of perennial vegetation on ecosystem structure and function in agricultural landscapes.

The first objective of this study is to quantify the influence of different proportions and landscape configurations of annual (e.g., corn and soybean) and perennial (e.g., prairie, savanna, agroforestry) plant communities on the storage, cycling, and output of nutrients, water, and carbon at the field and catchment scale. This objective will be achieved through field experimentation to examine the main hypothesis that strategic integration of perennial plant communities in agricultural landscapes will disproportionately improve nutrient, carbon and water fluxes—thereby reducing nutrient loads and movement of precipitation to surface waters and groundwater—while maintaining high productivity of the annual crop systems.

The second major objective of this study is to catalyze change on the landscape by promoting greater understanding among diverse groups of people (i.e., the public, policy makers, farmers, environmentalists, etc.) that agroecosystem production and environmental stewardship are compatible when appropriate combinations and configurations of perennial and annual plants are established. A major component of addressing this objective will involve educational and outreach activities coordinated through the Neal Smith NWR Prairie Learning Center. Below is a summary of the field activities completed during the fall of 2004:

Site selection: Twelve small watersheds (ranging in size from 1 to 7 ha) were selected for the study. Six of the watersheds are currently under brome grass, and 6 were planted from brome to native prairie during the winter of 2004. Three sampling points were marked in each watershed: shoulder, midslope, and toe. Each watershed was geo-referenced using a Tremble GPS unit, and detailed topographical maps are currently under construction using ArcView.

Hydrologic monitoring: Two groundwater wells were established in each watershed (shoulder and toe positions). Soil moisture access tubes were installed (to 1 m depth) at the shoulder, midslope and toe positions in each watershed (for monitoring soil moisture using a neutron probe). Suction lysimeters will be installed in December, 2004, also in all three watershed positions.

Soil sampling: Soil samples were collected from all watersheds and will be analyzed for nutrient content, soil organic matter, and physical properties this winter at the U.S. Forest Service’s laboratory in Grand Rapids, MN.

Collaboration: Researchers involved in this project and their respective institutions are as follows: Iowa State University: Rick Cruse, Matt Helmers, Matt Liebman, and Lisa Schulte. The National Soil Tilth Lab: Cindy Cambardella and Mark Tomer. Iowa Geologic Survey/DNR: Keith Schilling. U.S. Forest Service: Dave Lytle, Randy Kolka. New collaborators from Iowa State University who will likely participate in future research include: Cathy Kling, German Mora, Matt O’Neil, Jean Opsomer, and Silvia Secchi. Graduate students involved in the project include: Melissa Cheatham, Greg Shepherd, and Mario Perez-Bidegain. In addition, Maged Nosshi has been working as a research associate on this project since August 2004, and will most likely continue until August of 2005.

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Effects of grazing mammals on tallgrass prairie restorations

Principal Investigator: Brian Wilsey; Graduate Research Assistant: Leanne Martin, Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA

The presence of bison and prescribed fire, as well as the relatively large size of the reconstructed prairie at Neal Smith National Wildlife Refuge makes it an excellent site to test hypotheses concerning prairie restoration success. Our research project at NSM has two primary objectives: 1) to identify whether various aspects of plant diversity and ecosystem functioning have been restored successfully, and 2) determine how bison grazing is impacting plant diversity and ecosystem functioning of restorations.

The first part of our project was designed to quantitatively compare plant diversity and net primary productivity (NPP) between prairie plantings at NSM and nearby remnants (reference prairies), and to collect time 0 data for the second part of our project (see below). Plots of 6 x 8 m were established within 8 plantings at NSM and within three nearby reference prairies (Sheeder Prairie, Rolling Thunder Prairie, and A.C. Morris Prairie, 8 plots per remnant). Quadrats (0.4 m2) were clipped during 2002 and 2003 within each of the 8 plantings and the 3 remnants. This gave us eight plots north of the visitor road (planted with prairie mix plus 6 lbs/acre of Canada wildrye) and eight to the south (planted with prairie mix only). Above ground material was sorted into live and dead components, and live biomass was sorted by species, dried and weighed. Mean plant species richness, evenness, and overall diversity, and the proportion of native and exotic species was calculated at the quadrat (plant neighborhood) scale. An estimate of proportion of beta diversity (amount of "patchiness") was made by comparing mean quadrat-level estimates to estimates for the entire site. Within NSM, species evenness and diversity was higher and species richness was similar in plantings north of the road, where a cover crop was used, than in plantings south of the road, where a cover crop was not used. There were large differences in quadrat-scale species richness and the proportion of beta diversity between NSM and remnants. However, there were no significant differences in species evenness. These results suggest that large differences remain in the number of species and the patchiness of species between the prairie plantings at NSM and remnants. Seed addition studies (part 2) are in progress to determine if diversity can be increased by adding seed (i.e. if it is limited by the availability of seed.

The second part of our project was designed to determine if bison grazing is affecting plant diversity, NPP, proportion of grass and exotic species, and seedling establishment. In June 2003, a bison exclosure (8 x 6 m) was built within each of the 8 plantings at NSM. Within each planting, there are also two adjacent 8 x 6 m plots that were left open to bison activities. Seeds of ten rare plant species, including forbs, legumes, and grasses, were added to 1 x 1 m subplots within each of the plots in June 2003, and 25 species were added to an additional set of subplots in spring 2004 to repeat the experiment. Plots of the same size were established nearby to serve as controls for the seed addition. Seedlings were counted monthly in each of the plots for the remainder of the 2003 growing season (first seed addition) and in the 2004 growing season (first and second seed addition). Light availability and soil water were also measured to determine if grazing affects these variables that are so important to seedling establishment. Because the amount of grazing varies from site to site, and because this variation is important in predicting responses, we also estimated bison consumption rates by comparing biomass inside and outside of temporary exclosures. NPP was estimated as the amount of biomass accumulation plus the amount consumed by bison, and grazing intensity as (consumption/NPP)*100. Temporary exclosures were constructed in March 2004 and moved in June 2004, and biomass was clipped in June and August 2003, and in March, June, and August 2004.

Net primary production did not vary with grazing during June-August 2003 and April-June 2004, but was significantly greater in the grazed treatment during June-August 2004 after adding consumed biomass. Light availability was consistently higher in grazed plots than inside exclosures. Grazing intensity varied between June-August 2003 (mean GI: 49% of productivity consumed) and April-June 2004 (14%) and was highest in June-August 2004 (68%). Preliminary analyses indicate that species diversity measures did not differ between grazed and ungrazed plots. Neither the proportion of exotic species nor the proportion of C4 grasses differed between treatments. Seed addition analyses are ongoing. The large variability in grazing intensities suggests that establishment of seedlings may be patchy, and may occur only where grazing has optimized establishment conditions. Therefore, analyses of light, water and biomass variability in grazed versus ungrazed areas are ongoing.

Results from these two studies will help identify how well different components of ecosystem functioning and plant diversity have been restored. Also, as bison and other grazing mammals are more commonly reintroduced as part of restorations, it will be important to know what effects they are having. Knowledge from these studies will hopefully be helpful to management of prairies at this and other locations.

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Water Sampling at Walnut Creek National Wildlife Refuge

Principal Investigator: Keith E. Schilling Surface, Iowa Geological Survey, 109 Trowbridge Hall, Iowa City, IA

During Water Year 2004 (October 1, 2003 to September 30, 2004) the Iowa Geological Survey collected surface water samples on 22 occasions from Walnut and Squaw Creeks. Surface water samples were collected from 10 sites in both watersheds on a regular basis throughout the year. Sites are located at up and down-gradient USGS stream gauges, and three tributary locations. Surface water chemistry was monitored weekly in May and June, bi-monthly in April, July-September, and monthly in November to February. Water samples were analyzed for temperature, pH, specific conductance, dissolved oxygen, redox and turbidity in the field using a Hydrolab H20 water analyzer. Water samples are submitted to the University of Iowa Hygienic Laboratory for anions, fecal coliform, pesticides and phosphorus analyses.

Quantifying the Role of Riparian Land Use on Stream Bank Erosion and Nutrient Pollution

Principal Investigators: Thomas Isenhart and Richard Schultz, Department of Natural Resource Ecology and Management, Iowa State University, Ames; Keith Schilling, Iowa Geological Survey, Iowa City, Iowa

Sediment, phosphorus and nitrogen loading of Midwestern streams produces major pollution problems in these surface waters. While upland sediment and nutrient flow likely contribute to non-point source pollution of surface water sources, sediment and nutrient flows from riparian row cropped fields, congregating areas within riparian pastures, stream bank erosion, or direct deposition of feces and urine may be more important to stream water quality because of their proximity to the streams. Providing riparian buffers of perennial plant communities that are not grazed may dramatically reduce movement of pollutants from this source area.

Specific Objectives:

1. Measure the amounts of sediment and nutrient losses from stream bank erosion in riparian areas managed as ungrazed grasslands, grazed pastures, forested riparian areas, reestablished native prairie buffers or cropland with and without buffers on the Neal Smith National Wildlife Refuge and on producer farms in the Squaw Creek watershed.

2. Quantify the reduction of sediment and nutrient loss from stream bank erosion in grazed riparian areas where fencing excludes livestock from the channel on producer farms with whom we worked during a previous study.

3. Monitor a sub-set of stream bank erosion sites in northeast, central and southeastern Iowa from the previous study that have been monitored for 3 years. The extended survey time will provide more temporal data that is so critical for watershed studies.

Studying bank erosion at the Neal Smith National Wildlife Refuge provides a unique opportunity to observe the overall potential of reducing surface runoff and bank erosion in a landscape that is being converted from intensive row-crop and grazing agriculture to a landscape dominated by re-established prairie and savanna communities. Since 1995, the Neal Smith NWR and adjacent Walnut Creek watershed have been monitored for daily discharge and sediment. In 1998, a detailed survey of the 7 miles of stream channel in the Refuge was conducted. Variables measured during the survey included: left and right bank erosion, stream bed thickness, debris dams and livestock access, riparian land cover and tile locations. In addition, 25 detailed cross-sections were surveyed over the 7-mile stretch. A one mile reach of the creek is grazed by continuous stocking during the spring and summer months. In this reach, the survey demonstrated severe bank erosion and accumulation of fine stream bed sediment to depths of more than one foot. Numerous livestock entry points were observed along the reach. The data from this earlier work will provide a temporal comparison to the proposed survey of the stream in this proposal. During the period of time since the 1998 survey, significant progress has been made in re-establishing native prairie and savanna communities along the stream. In 1998, it was estimated that stream bank erosion accounted for 51% of the sediment load in the channel. With the increase in perennial plantings along the channel since that time, it is assumed that stream bank erosion contributions to channel sediment load have increased. Channel morphology has also changed during this time period. New cross-sections should show that the channel has been actively widening following earlier incision. The rapid widening contributes to the high sediment load from stream bank erosion.

The Squaw Creek watershed remains in row-crop and grass pasture cover, typical of much of the north-central part of the state. This watershed had higher annual sediment loads than Walnut Creek in 1998. Greater differences may now be expected after 6 years of extensive perennial plant community establishment in Walnut Creek. The comparisons of these two-paired watersheds will provide a baseline of the potential reductions in stream bank sediment production that could achieved with total perennialization of the watershed. While this is unlikely to happen in any other watershed in Iowa, it provides an upper limit of the kind of reductions that could be possible.

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Beyond site-specific assembly rules: species traits as predictors of the frequency of occurrence of Lepidoptera in restored tallgrass prairies

Principal Investigator: Keith S. Summerville, Ph. D., Department of Environmental Science and Policy, Drake University, Des Moines, Iowa

Restoration ecologists are increasingly turning to the development of trait-filter models to predict how species move from regional species pool into a restored community. Two often untested assumptions of these models, however, are that ecologists have an understanding for which traits are predictors of species distribution and whether traits interact to determine the community membership. The goals of this study were to sample the regional species pool of Lepidoptera and to determine whether combinations of species traits predispose species toward becoming members of the actual species pool within restored prairies. In 2004, we sampled 259 moth species from 13 Tallgrass prairie remnants and restorations in central Iowa, including 164 species from Neal Smith National Wildlife Refuge. We used principle components analysis (PCA) to identify significant combinations of ecological traits that were shard by large groups of moth species. Logistic regression was then employed to test for significant effects of the trait combinations on the frequency of prairie sites occupied by moth species. The PCA partitioned eight moth traits into four axes that explained a total of 81.6% of the variance. Furthermore, our logistic regression model detected highly significant effects for all PCA axes on the fraction of sites occupied by moths. Species most frequently filtered from the regional species pool into prairies were those that: (1) had long flight periods and were multivoltine (2) displayed a feeding preference for legumes but not the Asteraceae or other forb families, and (3) were regionally abundant but relatively small in body size. Ordination revealed significant differences in moth community composition among prairie sites, suggesting trait differences among species partly drive patterns of β-diversity among prairie sites. Finally, our results suggest that a combination of stochastic and deterministic mechanisms interact to determine how moths attain community membership within restored habitats, and that these processes may operate relatively slowly for univoltine forb specialists with restricted distributions.

** This research is being written in manuscript form for submission to the journal Conservation Biology in spring 2005.

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Note: Beginning in 2005, Dr. Summerville will use a multi-year grant from USDA to continue his butterfly and moth research at Neal Smith National Wildlife Refuge.

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Monarch butterfly activity at Neal Smith National Wildlife Refuge: summer and fall 2004

Principal Investigator: Robert D. Woodward, Ellis and Nelle Levitt Professor, Drake University, Des Moines, Iowa

The monarch butterfly activity at Neal Smith National Wildlife Refuge was observed from late June through the end of September 2004 to determine the extent of the both the “resident population” in the summer and visits by monarchs during the fall migration period.

Field observations tended to show the importance of Neal Smith as a key refuge for monarchs in the contemporary environment. Reports from other parts of the nation in 2004 suggested a dramatic decline in the monarch population yet substantial monarch activity was documented by field observations in the summer and fall at Neal Smith.

An old seed production site on the Refuge was used as the primary study area for observing summer monarch activity. In the small area, the variety of wildflowers and milkweeds—the host plants for monarch caterpillars—regularly attracted monarchs from June 23 through August 27. Away from the Refuge across central Iowa, monarchs were being reported much less often. One factor at Neal Smith coincided with many reports from Iowa and other parts of the nation—that few monarch caterpillars were being observed on milkweed leaves. Daily studies of milkweeds in the production site and other areas of Neal Smith indicated little to no presence of the caterpillars.

Nationally, several major studies were reporting significant declines of the numbers of monarchs migrating during the fall 2004. However, at Neal Smith, solid migratory activity was observed from late August until the end of September. Anecdotal reports for the period can be found at http://www.drake.edu/monarch/migration2004.html . Based on yearly studies of fall migration over central Iowa since 1997, it’s fair to say Neal Smith has become a key stopover area for migrating monarchs.

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The Reintroduction of a Declining Insect Associated with an Endangered Ecosystem: A Case Study with Speyeria idalia (Regal Fritillary) in a Reconstructed Prairie in Central Iowa

Principal Investigators: Diane M. Debinski and Stephanie Shepherd, Ecology, Evolution and Organismal Biology, 353 Bessey Hall, Iowa State University, Ames, IA

Abstract: The decline of many prairie endemic butterfly species in the Midwestern United States has been well documented. These species declines are strongly associated with the destruction and fragmentation of their prairie habitat. One conservation strategy that can be used to compensate for both the loss of prairie and its endemic insect fauna is the reintroduction of rare butterfly species into reconstructed prairie areas. We are examining approaches to reintroduce Speyeria idalia, a declining prairie endemic butterfly, to a 1,250-hectare reconstructed prairie at Neal Smith National Wildlife Refuge, in Iowa. We first established 1,980 individuals of S. idalia’s host plant, Viola pedatifida (blue prairie violet) at the Refuge during 1998-1999. Then a total of seven gravid S. idalia females were moved during 2000-2001 from two abundant source populations to the Refuge and placed in mesh cages over violet plots. Surveys for larvae and adults were conducted during the summers following reintroduction. In 2002 and 2003, adult S. idalia were sighted in several places across the Refuge in early July and they persisted through late August. Maximum numbers observed were on the order of 84 individuals. The presence of females was never confirmed on Refuge property during 2002 or 2003. However, during 2004, the butterfly was still present in good numbers and females were documented on the Refuge. Therefore, it appears that in the case of S. idalia, reconstructed prairies may serve as adequate habitat. Additional time will be required to determine whether the population will sustain long-term viability.

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Evaluation of isolated and integrated prairie reconstructions as habitat for prairie butterflies

Principal Investigators: Stephanie Shepherd and Diane M. Debinski, Ecology Evolution, and Organismal Biology, 353 Bessey Hall, Iowa State University, Ames, IA

Reconstructing prairie habitat is one of the most promising techniques for conserving the imperiled prairie ecosystem and its associated organisms. However the degree to which reconstructed prairies function like remnant prairies has not been fully examined. We evaluated the effect of restoration planting prescriptions, management, and vegetative quality on butterfly communities inhabiting prairie reconstructions in central Iowa, USA. Twelve isolated reconstructed prairies (small, surrounded by agriculture), 12 integrated reconstructions (planting units in a larger matrix of reconstructed and remnant prairies at Neal Smith NWR), and 12 remnant prairies were surveyed for butterfly and plant diversity, abundance and composition. Remnant prairies supported significantly higher butterfly richness and plant diversity but were not significantly different from reconstructions in butterfly species composition and abundance. Remnant prairies also supported significantly higher richness and abundance of habitat-sensitive butterfly species. Reconstructions that were the most similar to remnant prairies in plant diversity and % native plant species did not support significantly different butterfly communities than lesser quality reconstructions based on measures of butterfly richness, abundance and composition. However, butterfly richness and abundance were highest on high quality reconstructions. There was also a trend towards higher butterfly richness on integrated reconstructions (sites at Neal Smith NWR) when compared to isolated reconstructions. Finally, the best vegetative predictors of butterfly richness (R² = 0.38) and abundance (R² = 0.13) were the availability of nectar and the % cover of duff (which is related to management issues such as time since burning). In conclusion, we found that the response of the butterfly community to vegetation in a reconstructed prairie is more complex than simply a response to vegetation diversity. Both management and landscape context of the restoration also play an important role (Photo 8).

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Arthropod collecting at the Neal Smith National Wildlife Refuge

Principal Investigator: Steve M. Spangler, Ph.D, CCA, 9468 Indian Hills Drive, Clive, IA

The objective of this preliminary work was to develop a framework for future long-term, funded studies relating to re-establishment of arthropod communities associated with the on-going tallgrass prairie reconstruction at the Refuge.

Various arthropod-collecting techniques were used as outlined below. The following sites, as recommended by the Refuge Biologists, are referenced in the discussion below: ‘NE Entrance’, ‘Cabbage’, ‘Dogleg’, and ‘Coneflower’.

Three sets of five sweeps per location were taken at the NE Entrance, Cabbage, and Dogleg sites, on September 3, at about 11 AM.

Three to five traps were used at the NE Entrance, Cabbage, Dogleg, and Coneflower sites, for a 48-hour period, from about 11 AM on September 3, through 11 AM on September 5.

One Malaise trap at each of the NE Entrance and Cabbage sites, for a 48-hr period, from about 11 AM on September 3 to about 11 AM on September 5.

One light trap at each of the NE Entrance and Cabbage sites, for a 24-hr period, from about 11 AM on September 8 to about 11 AM on September 9.

An entomological collection is being developed at the entomology laboratory at NSM as specimens are identified. It is anticipated that specimens of the Homoptera, Hemiptera, and Coleoptera will be identified eventually to the species level. Other taxa that are analyzed will be identified to Family level.

Ten to 15 species of Homoptera. Hemiptera and Coleoptera were identified from the sweep sampling from the NE Entrance, Cabbage, and Dogleg sites. Indices of diversity (richness, H’, J’) indicated fairly similar levels of diversity. However, the habitat closest to agricultural habitat, the Cabbage site, tended to have certain species much more abundant which are common in agricultural habitats (Empoasca sp., Lygus lineloaris, Diabrotica sp.).

A note of caution here is that these habitats at the NSM can have noticeably different volume of vegetation, which may result sampling errors in comparing habitats because of variable sampling efficiencies relative. In the future, foliage sampling may need to be done with a method other than sweep net sampling.

Ten to 15 species of Homoptera. Hemiptera and Coleoptera were identified from the sweep sampling from the NE Entrance, Cabbage, and Dogleg sites. Indices of diversity (richness, H’, J’) indicated fairly similar levels of diversity. In contrast to the sweep net sampling, one taxon common in agricultural habitats (Empoasca sp.). was more common in the Malaise traps.

Five to 15 species of ground-dwelling Collembola, Coleoptera, Hymenoptera, and Orthoptera were identified from the pitfall sampling from the NE Entrance, Cabbage, and Dogleg sites. Indices of diversity (richness, H’, J’) were highest in the Dogleg site; this site had greater numbers of ant (Formicidae) species, and also had greater numbers of Gryllidae. The NE Entrance and Dogleg sites, particularly the Dogleg site, also had noticeably greater numbers of ground beetles (Carabidae). Springtails (Collembola), which feed on dead plant material (detritus), were noticeably more abundant in the reconstructed sites (NE Entrance and Dogleg) compare3d with the first-year site (Cabbage). Thius, in general, these pitfall trap samples indicated greater abundance and number of species of ground-dwelling ants (Formicidae), springtails (Collembola), and ground beetles (Carabidae).

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Survey of Mycorrhizal Symbioses at Neal Smith National Wildlife Refuge

Principal Investigator: Inger Lamb

Evaluating the effects of the soil system on seedling establishment and growth is a complex task. In addition to soil mineral and nutrient availability, the below-ground biological component has an enormous potential to influence plant growth and survival. The sheer complexity of the interactions and influences of the soil biological and mineral environment can make research intimidating.

Nevertheless, projects designed to establish vigorous and long-lived perennial ecosystems (especially on soils in transition from traditional agricultural practices) require an understanding of the soil microflora if they are to be successful. In Iowa there is considerable interest in establishment of native perennial plants, for a variety of reasons ranging from re-establishment of the original ecosystem to energy and food production from low input perennial plant systems. Any desire to mimic the original flora must include consideration of the soil environment. Optimal soil properties and function are also very important to consider when designing or developing a reduced-input perennial production system.

Mycorrhizae are one of the soil biological components frequently ignored or at best poorly evaluated and understood. Essentially no research has been done documenting the extent or importance of mycorrhizae in Iowa prairies. This is unfortunate considering the potential benefits and essential nature of this common root-fungal symbiosis, and the probable importance in the prairie ecosystems being re-established in Iowa.

This study involves a survey of mycorrhizal associations in remnant (virgin) and reconstructed prairies at Neal Smith National Wildlife Refuge. Techniques for root sample processing and spore isolation and identification will be developed to fit the facilities. The results will be establishment of baseline data and experimental protocols, that will be used to direct and develop future research on this important soil component. Data produced will be made available to any interested party, with the intent of encouraging follow-up studies by graduate students, interns, and other researchers from a wide range of institutions. Sampling is scheduled to begin in December, 2004.

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Evaluation of methods for Canada thistle-free habitat restoration

Brd Principal Contact: Diane Larson, Research Wildlife Biologist

Affiliation: Northern Prairie Wildlife Research Center

The National Wildlife Refuge System has an active habitat restoration program and annually seeds thousands of hectares to native plant species. In FY2003 alone, Region 3 restored 26,690 wetland acres and 7,394 upland acres. The noxious weed, Canada thistle (Cirsium arvense), plagues these restorations, however. Because its control is mandated by law, it is often necessary to apply herbicide or mow at a time that is detrimental to the success of the restoration as a whole. Disturbance at this early stage of the restoration may, in fact, weaken the native seedlings as much or more than it does Canada thistle, thus thwarting the potential of the native restoration to ultimately suppress Canada thistle and other weedy species. Continued control of Canada thistle may perpetuate the repeated disturbances that favor infestation by a variety of exotic plants, thistle included. The goal of the proposed research is to compare the ability of differing seed mixes and application techniques to suppress Canada thistle establishment in new restorations. We hypothesize that by increasing competition and decreasing the disturbance inherent in seeding, we can produce more weed-resistant restorations.

Potential effects on Canada thistle abundance in restoration of cultivated land is divided into four categories: (1) disturbance, (2) competition, (3) site characteristics and (4) year effects. We will experimentally manipulate disturbance and competition, but must also take into account site characteristics and year effects. Three seeding techniques will constitute differing amounts of disturbance: broadcast seeding during the dormant season is expected to inflict the least disturbance to the seedbed, spring seeding with a seed drill the most, and spring broadcast seeding should be intermediate. We will vary competition through the use of three different seed mixtures. A cool-season grass dominated mix should compete directly with Canada thistle seedlings, which also emerge early in the spring. A warm-season grass dominated mix, while emerging later than Canada thistle, may be more efficient at nutrient uptake and ultimately out-compete thistle through nutrient usurpation. Each of these mixes will have low diversity (8 species). A high diversity mix (at least 35 species) with several species from each functional group may effectively utilize all available niches, thus excluding Canada thistle. Site characteristics we will need to take into account include the existing Canada thistle propagule bank and soil fertility and moisture. Year to year variation, over which we have no control, include seasonal temperature and precipitation, which will influence both the probability of Canada thistle and native seedling establishment, though perhaps not equally.

The study will be conducted at Neal Smith National Wildlife Refuge, Fergus Falls Wetland Management District, Morris Wetland Management District, Litchfield Wetland Management District and Minnesota Valley National Wildlife Refuge. Total area treated in each field will be approximately 4 acres. The 4 acres will be divided into 108 cells, each 12.2 x 12.2 m (40 ft x 40 ft, or 0.0367 acre), which will allow five passes by a typical 2.44 m (8 ft.) seed drill. Sampling (see below) will be restricted to a 2 x 6 m plot in the center of the treated cell to avoid edge effects. To minimize disturbance, cells will be oriented in the field such that each can be reached without crossing another cell; a buffer zone will separate rows of cells to accommodate equipment and site access. Treatments will be assigned to cells at random with 12 replications per treatment in each field.

We will employ three seeding methods and three seed mixes, fully crossed, for a total of nine treatments. The three seeding methods include a dormant season broadcast seed application, a spring broadcast seed application, and a spring seed drilling application. Seed mixes will include two low diversity mixes, one dominated by warm-season grasses, similar to currently used seed mixes, and the other dominated by cool-season grasses. Total species richness in the mix will include only one or two species in each functional group, with the exception of the cool- or warm-season grasses, which will have three or four species. The high diversity mix will include at least seven species in each functional group. Functional groups include warm-season grasses, cool-season grasses, warm-season forbs, cool-season forbs, and legumes. To the extent possible, seeds will be collected from sites near the fields to be seeded. Additional seed will be purchased from the nearest available supplier as needed. We will plant 50-60 seeds/m² in the drilled application and 60-75 seeds/m² for broadcast seedings. Fields will be mowed once in the first year for weed control. We will apply glyphosate and 2,4-D to the spring broadcast field prior to seeding, per normal restoration practice.

Prior to seeding, we will collect soil samples from each cell in each field. Soil will be collected within a 0.5m buffer around each plot using a 2.54 x 10 cm soil corer. We will collect five cores in each of the cells and composite the soil over 4-cell blocks (to retain some geographic structure in the data). Soil thus collected will be used to determine average (1) nitrogen availability, (2) soil moisture, and (3) the Canada thistle propagule bank in each field, as well as any gradients across each field. Soil on all fields will be collected within a one-week period.

To assess nitrogen availability in soils we will perform lab incubations on a subset of the soil (approximately 1/5 of soil collected). We first will extract a sub-sample of the collected air-dried soil (referred to as the “initial” sample) with 2 M KCl. A second sub-sample of equal portion will be brought to field capacity (optimal moisture conditions for microbial activity), covered, and allowed to incubate for 28 days at room temperature. Following the 28-day incubation, the sample will be extracted with 2M KCl (the “final” sample). Extracts will then be analyzed for nitrate/nitrite and ammonium, the common available nitrogen compounds in soil using an OI Corporation SF3000 autoanalyzer. Subtracting the initial sample value from the final sample value gives the potential rate of nitrogen mineralization and nitrification, or the potential amount of nitrogen available to plants under ideal conditions, which provides a basis for comparison among the fields. Details of the methods can be found in Robertson (1999).

Rather than measuring soil moisture directly, which is costly and difficult across large landscapes, we will determine soil texture (% sand, silt and clay).  Soil texture is directly related to water holding capacity and will provide, together with precipitation, an index of relative moisture at each site.  We will use the hydrometer method as outlined in Day (1965).

Gross (1990) determined that germination with stratification was the most reliable method to assess viable soil seedbanks. To determine the number of Canada thistle propagules in each field we will first sieve the soil to remove root fragments > 2 cm. Root fragments will be mixed with sterilized potting soil and spread over a 2.5 cm layer of vermiculite in greenhouse flats. A paper towel will separate the vermiculite from the soil. Remaining soil will be cold stratified for 6 weeks, then spread to a depth of 2 cm over a 2.5 cm layer of vermiculite, separated by paper toweling, in greenhouse flats. Flats will be placed in a greenhouse and kept moist, with light regime and temperature consistent with the growing season in the upper Midwest. Root fragments and seedlings will be allowed to grow until no new plants are detected for 7 days. At this point, plants or seedlings that can be identified as Canada thistle will be counted and removed. If identification is equivocal, seedlings will be allowed to continue growth until they can be identified; this may entail transplanting seedlings to larger pots. Results will be expressed as average number of Canada thistle root sprouts and seedlings per cubic meter of soil in each field. We will also assess any gradients across each field.

For post-treatment sampling, we will sample the plant community on each plot using a composite of 12-0.5 x 2 m quadrats. The quadrats will allow more complete searches for individual species, while dividing the plot into sufficiently small sections for accurate cover estimation. On each quadrat we will determine aerial cover of each species using Daubenmire cover classes (Daubenmire 1959). We have chosen to use aerial cover because it is directly related to biomass (Elzinga et al. 1998). Coefficients of Conservatism will be assigned to each species, based on published sources. In addition, we will conduct Canada thistle stem counts on a sub-sample of each plot, with the size of the sub-sample depending on the density of Canada thistle stems. Counts will be standardized to stems/m². The plant community will be assessed in May and July of each year. Canada thistle stem counts will be assessed in July.

Expected Products: Results of this project will be incorporated into management recommendations for planting methods and seed mixtures when Canada thistle and other invasive plants threaten prairie restorations. The sampling design and monitoring protocols are fully transferable to other refuges with prairie habitat. The measurement model developed for this project can also guide future monitoring efforts by identifying additional factors that influence invasibility and that may interact with factors we can manipulate to produce varying – and unexpected – results.

We anticipate, in addition to annual and final reports to the refuges and Region 3, at least two peer-reviewed publication and several oral presentations at meetings and workshops as appropriate. The topic of one paper will be the outcome of the restoration trials. The topic of the second paper will be the utility of multivariate hypothesis testing (e.g., structural equation modeling) for the development of monitoring plans. All reports and publications will be available through the Northern Prairie Wildlife Research Center (NPWRC) web site.

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Publications Resulting from Research Conducted at NSM this Year:

Lewis, M. N., R. M. Steichen, and K. S. Summerville. (in press). The diversity of moths in Tallgrass prairies of Iowa: a preliminary assessment. Journal of the Iowa Academy of Sciences. (Publication expected in March 2005).

Summerville, K. S., M. N. Lewis, and R. M. Steichen. (in press). Restoring lepidopteran communities to savanna remnants: contrasting effects of habitat quantity and quality. Restoration Ecology. (Publication expected in the second quarter, 2005).

Zhang, Y-K, and K.E. Schilling. 2004. Effects of land cover on evapotranspiration, soil moisture and groundwater table and recharge: field observations and assessment. Journal of Hydrology. In review.

Zhang, Y-K, and K.E. Schilling. 2004. Impact of vegetation on main hydrological processes: a field study and its implication for water quality. Advance in Earth Sciences 19(3): 422-428.

Drobney, P.M. and K.E. Schilling. 2003. Treatment of Reed Canary Grass Monoculture Improves Water Table Levels for Sedge Meadow Restoration (Iowa). Restoration and Management Notes. 21(4):323-324.

Schilling, K.E., Zhang, Y-K, and P. Drobney. 2003. Water Table Fluctuations Near an Incised Stream, Walnut Creek, Iowa. Journal of Hydrology. 286:236-248.

Zhang, Y-K, and K.E. Schilling. 2003. Temporal Scaling of Hydraulic Head and River Baseflow with Implications for Groundwater Recharge. Water Resources Research. W03504, doi:10.1029/2003WR002094.

Grants Supporting Research at NSM:

Hydrologic Studies: Keith Schilling et al.

USDA, Conservation Effects Assessment Project (CEAP)Iowa State University to evaluate economics of conservation practices in three watersheds in Iowa - $645,000

(NOTE: One watershed evaluated in this study is the Walnut Creek watershed – primary evaluation of the Walnut Creek watershed will be by the Iowa Geological Survey. A calibrated SWAT model and sediment delivery model will be constructed for the Walnut /Squaw Creek basins by IGS personnel. The model will be given to ISU economics team for evaluation of conservation cost/benefits.) Grant date: October 1, 2004.

Savanna Research: Heidi Asbjornsen et al

Iowa State University: $38,000

U.S. Forest Service: ca. $60,000

Agroecosystem Research: Heidi Asbjornsen et al

U.S. Forest Service: ca. $100,000

Leopold Center for Sustainable Agriculture: $125,000

Iowa State University’s Agroecosystem Initiative: ca. $110,000

Streambank Erosion and Nutrient Pollution: Tom Isenhart et al

Leopold Center for Sustainable Agriculture: $177,230

Moth Studies: Keith Summerville

National Aeronautical and Space Administration: $10,000. Duration - 1 year.

National Geographic Society: $15,000. Duration - 1 year.

Drake University small research grant: $10,000. Duration - 1 year.

USDA Managed Ecosystem Grant: $70,000. Granted for 2005. Duration is 2.5 years.

Mycorrhizal study: Inger Lamb et al

Leopold Center for Sustainable Agriculture. $25,000. Granted for late 2004 through 2005.

Canada Thistle Study: Diane Larson et al. (Note: this study includes 4 FWS stations).

United States Geological Service. $192,000

FWS, Region 3. $68,500

Total funding contributing to research at NSM this year: $1M

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COMMON NAME	SPECIES	# POINTS OBS.	TOTAL #
Red-Winged Blackbird	RWBL	48	177
Common Yellowthroat	COYE	44	72
American Goldfinch	AMGO	39	68
Gray Catbird	GRCA	36	67
House Wren	HOWR	35	63
American Robin	AMRO	30	43
Brown-Headed Cowbird	BHCO	23	36
Song Sparrow	SOSP	25	36
Northern Cardinal	NOCA	25	32
Barn Swallow	BARS	19	30
Mourning Dove	MODO	19	27
Dickcissel	DICK	17	26
Killdeer	KILL	15	26
Indigo Bunting	INBU	17	21
Vesper Sparrow	VESP	15	21
Willow Flycatcher	WIFL	16	20
Cliff Swallow	CLSW	6	19
Rose-Breasted Grosbeak	RBGR	16	19
Bobolink	BOBO	3	17
Downy Woodpecker	DOWO	16	17
White-Breasted Nuthatch	WBNU	11	17
Red-Bellied Woodpecker	RBWO	12	16
Horned Lark	HOLA	9	15
Sedge Wren	SEWR	10	14
Eastern Kingbird	EAKI	12	13
Blue Jay	BLJA	9	12
Field Sparrow	FISP	10	12
Great-Crested Flycatcher	GCFL	8	12
Black-Capped Chickadee	BCCH	6	11
Eastern Bluebird	EABL	5	11
Northern Oriole	NOOR	11	11
Eastern Wood-Peewee	EAWP	9	10
Yellow Warbler	YWAR	10	10
Common Grackle	COGR	8	9
Hairy Woodpecker	HAWO	9	9
Brown Thrasher	BRTH	7	7
Eastern Meadowlark	EAME	7	7
Grasshopper Sparrow	GRSP	6	7
Henslow's Sparrow	HESP	5	7
Rufous-Sided Towhee	RSTO	7	7
Yellow-Billed Cuckoo	YBCU	6	6
Northern Flicker	NOFL	5	5
European Starling	EUST	2	3
House Finch	HOFI	3	3
Lark Sparrow	LASP	2	3
Red-Eyed Vireo	REVI	3	3
Unknown Meadowlark	UNME	3	3
Cerulean Warbler	CERW	2	2
Orchard Oriole	OROR	2	2
Red-Headed Woodpecker	RHWO	1	2
Ring-Necked Pheasant	RNPH	2	2
Tree Swallow	TRES	2	2
Bank Swallow	BANS	1	1
Great-Horned Owl	GHOW	1	1
Loggerhead Shrike	LOSH	1	1
Pileated Woodpecker	PIWO	1	1
Purple Martin	PUMA	1	1
Red-Tailed Hawk	RTHA	1	1
Western Meadowlark	WEME	1	1
Wood Thrush	WOTH	1	1