Escape tactics used by bluegills and fathead minnows to avoid predation by tiger muskellunge

To explain why esocids prefer cylindrical, soft-rayed prey over compressed, spiny-rayed prey, we quantified behavioral interaction between tiger muskellunge (F1 hybrid of male northern pike Esox lucius and female muskellunge E. masquinongy) and fathead minnows (Pimephales promelas) and bluegills (Lepomis macrochirus). Tiger muskellunge required four times as many strikes and longer pursuits to capture bluegills than fathead minnows. Tiger muskellunge attacked each prey species differently; fathead minnows were grasped at midbody and bluegills were attacked in the caudal area. Each prey species exhibited different escape tactics. Fathead minnows remained in open water and consistently schooled; bluegills dispersed throughout the tank and sought cover by moving to corners and edges. Due to their antipredatory behavior (dispersing, cover seeking, and remaining motionless) and morphology (deep body and spines), bluegills were less susceptible to capture by tiger muskellunge than were fathead minnows.Funding for this project was provided by the Federal Aid in Fish Restoration Act under Dingell-Johnson Project F-57-R

Modification of the Iowa State University-Vegetative Treatment Area Model

Vegetative Treatment Systems (VTSs) are currently being used at several open beef feedlots across Iowa as an alternative to traditional feedlot runoff containment systems. There are two types of VTS: a VTA system which is comprised of solids settling basin (SSB) followed by a vegetative treatment area (VTA), and a VIB-VTA system which is comprised of a solids settling basin followed by a vegetative infiltration basin (VIB) and a VTA. Iowa State University developed two computer models to simulate VTS performance. When model predictions were compared with data collected from four Iowa sites, the models were found to under predict the VTA outflow, VIB outflow, and nutrient concentrations in the SSB outflow. This paper focuses on the modifications made to the Iowa State University VTA model. To identify the problems with the model, the graphical and numerical outputs were examined for values that were either not reasonable or did not fit the expected behavior of the system. Three major problem areas were identified in the VTA model: an extremely high rate of water removal from the VTA, incorrect calculation of soil moisture, and incorrect tracking of the water table (especially in high water table situations). Each of these problems was isolated and the code controlling this function of the model was examined. Potential solutions were tested to see if they accurately simulated VTS behavior. If successful, the solutions were then implemented. These modifications and their impact on model performance are discussed in this paper

Evaluation of Vegetative Treatment System Performance of CAFO Beef Feedlot Runoff Control

Rules released by EPA in 2003 require beef feedlots defined as Concentrated Animal Feeding Operations (CAFO) to control rainfall runoff from their feedlots. The rules included verbiage that allowed for the design and use of “Alternative Technologies” and require that any “Alternative Technology” be modeled to show they are at the least as effective as traditional storage systems. The objective of this project is to evaluate, through field monitoring, the performance of vegetative treatment systems (VTSs). Six Iowa beef feedlots are being monitored, and through additional funding and partnering organizations, four other sites are being monitored in Nebraska, Minnesota, and South Dakota. Results from the Iowa sites thus far have shown nutrient mass release reductions 40 – 99% as compared to a settling basin only system

Hydrogen Sulfide and Nonmethane Hydrocarbon Emissions from Broiler Houses in the Southeastern United States

Hydrogen sulfide (H2S) and nonmethane hydrocarbon (NMHC) emissions from two mechanically ventilated commercial broiler houses located in the southeastern United States were continuously monitored over 12 flocks for a one-year period during 2006-2007 as a joint effort between Iowa State University and the University of Kentucky. H2S and NMHC concentrations were measured using UV-Fluorescence H2S analyzers and methane/nonmethane/total hydrocarbon dual flame ionization detector gas chromatographs. Ventilation rates in each house were measured continuously by monitoring building static pressure and operational status of all ventilation fans in conjunction with individual performance curves developed and verified in situ using a Fan Assessment Numeration System (FANS) unit. United States EPA methods TO-15 and TO-17 were used for the nonmethane hydrocarbon compound speciation. The top-25 compounds are presented. The overall mean H2S and NMHC emission rates for a one-year period were 65.7 ± 42 g/d-house and 0.76 ± 0.43 kg C3H8/d-house, respectively. Annual H2S emission for the two broiler houses (including downtime emissions) averaged 19.2 kg per year per house or 0.147 g per bird marketed when the birds were marketed at 52 days of age with a stocking density of 11.8 bird per m2 (1.1 bird per ft2). Annual NMHC emission averaged 231 kg per year per house (510 lb per year per house) or 1.77 g per bird marketed

End-to-end simulations of different coronagraphic techniques

The NASA exoplanet exploration program is dedicated to developing technologies for detecting and characterizing extrasolar planets. In support of that program we have evaluated three different coronagraphic techniques (bandlimited Lyot, optical vortex, and phase-induced pupil apodization) using optical propagation simulations. These utilized a complete hypothetical telescope+coronagraph system with phase and amplitude aberrations. Wavefront control using dual sequential deformable mirrors was performed. We discuss the different computational techniques necessary to accurately simulate each coronagraph

Comparison of Construction Costs for Vegetated Treatment Systems in the Midwest

Vegetated treatment systems (VTSs) provide an alternative to containment basin systems for beef feedlot runoff control. Beef producers in the Midwestern United States have shown an increasing interest in using VTSs as a perceived lower cost option to containment basin systems. This paper reports the actual construction costs associated with 21 VTSs (eight on permitted Concentrated Animal Feeding Operations (CAFOs) and 13 on non permitted Animal Feeding Operations (AFOs)) located within Iowa, Minnesota, South Dakota, and Nebraska. The VTS construction costs are reported on a per head basis in 2009 adjusted dollars for each system. Cost comparisons are presented between CAFO and AFO facilities, by location and by system type. Additionally, estimated construction cost comparisons between open feedlots with VTS systems, open feedlots with containment basins, monoslope barns and hoop structure beef production systems are provided. Results from the cost comparison indicate that monoslope barns with concrete floors are the highest cost at $621 per head on average followed by hoop structures at$395 per head. Vegetated Treatment Systems designed for CAFO facilities ($77 per head avg.) are less expensive to construct than a traditional containment basin ($129 per head avg.) The same results indicated that an AFO VTS ($62 per head avg.) was less expensive to build than a containment basin on a similar facility ($195 per head). The data indicated that the least expensive VTS for an AFO is a sloped or sloped and level VTA ($42 per head avg.) followed by a pump sloped VTA ($68 per head avg.) and a sprinkler VTS ($87 per head avg.)

Quantification of Particulate Emissions from Broiler Houses in the Southeastern United States

Emissions of total suspended particulate (TSP), particulate matter with aerodynamic diameters = 10 µm (PM10), and = 2.5 µm (PM2.5) were continuously monitored at two mechanically ventilated broiler houses in the southeastern United States. Monitoring was performed over a one-year period during 2005-2006 as a joint effort between Iowa State University and the University of Kentucky. Tapered Element Oscillating Microbalances (TEOMs) were used to measure three species of particulate matter (TSP, PM10 and PM2.5). Ventilation rates were measured continuously by monitoring building static pressure and operational status of ventilation fans in conjunction with individual performance curves developed and verified in situ using a Fan Assessment Numeration System (FANS) unit. The magnitude of the TSP, PM10 and PM2.5 emissions are reported as a) annual house total emission and b) on a per 1,000 birds marketed basis. These emission values are: a) 785 kg (1,731 lb) TSP, 330 kg (727 lb) PM10, and 32.5 kg (71.7 lb) PM2.5 per house per year and b) 6.03 kg (13.3 lb) TSP, 2.52 kg (5.56 lb) PM10, and 0.25 kg (0.55 lb) PM2.5, per 1,000 birds marketed. Bird age is the predominant factor influencing particulate emissions. An empirical equation is presented that relates emissions to bird age for the monitored broiler houses. The use of a daily emission factor is not advised for broiler production systems or others in which substantial progressive animal growth occurs over time. The use of emissions per 1,000 birds marketed more realistically expresses emissions and allows for improved emissions inventory tracking

Vegetated Treatment System Models: Modeled vs. Measured Performance

Vegetated treatment systems (VTS) are designed to control runoff from beef feedlots. A VTS consists of a solids settling basin followed by either a vegetated treatment area (VTA) or a vegetated infiltration basin (VIB) followed by a VTA. Two computer models were developed at Iowa State University (ISU) to simulate traditional containment, a VTS with a settling basin and a VTA, and a VTS with a settling basin, VIB, and VTA. The models predict runoff volume and nutrient mass entering and leaving the system for a given design and specific weather conditions. In this paper, the monitored performance of four feedlot VTSs in Iowa is compared to the performance predicted by each site model run. These sites are undergoing extensive monitoring to determine the mass of nutrients discharged from each system component. Weather data including maximum temperature, minimum temperature and precipitation are also continuously recorded. System component discharge data collected at each site is compared to data generated by the model using site specific weather data for model calibration purposes. Comparisons of modeled versus monitored system performance indicate that the VTS models currently under predict discharge from the VTAs at all four sites. The VTS models also under predicted the VIB performance for both of the VIB sites. While the measured and monitored flow volumes from the SSB matched relatively well, the nutrient concentration released from the SSB was much higher than the concentration predicted by the VTS models

Performance of Six Vegetative Treatment Systems for Controlling Runoff from Open Beef Feedlots in Iowa

Beef feedlots of all sizes are looking for more cost-effective solutions for managing feedlot runoff. Vegetative treatment systems (VTSs) are one potential option that has been proposed. Iowa State University (ISU) has monitored the performance of six VTSs on open beef feedlots throughout Iowa since 2006. These feedlots have interim, National Pollution Discharge Elimination System (NPDES) permits that allow the use of VTSs to control and treat feedlot runoff. As part of the permit requirements for these feedlots the effluent volumes, nutrient concentrations, and nutrient masses exiting each component of the VTS were monitored. This paper describes the VTSs and monitoring methods used in this study and evaluates the effectiveness, in terms of both effluent concentration and nutrient mass transport reductions, of each system. During the three-year monitoring period, results have shown that VTSs are capable of reducing the nutrient mass exiting the VTSs by 65 – 99% as compared to a settling basin only system, with performance varying by both site and year. In addition to overall mass transport reductions, nutrient concentrations were also reduced, typically reduced by 50-90%, during treatment. Furthermore, monitoring results have shown a consistent improvement in system performance during the three years of the study. Much of this improvement can be attributed to improved management techniques and system modifications that addressed key performance issues