The Gunnison Basin Sage-grouse Strategic Committee: A Colorado County’s Fight for Conservation Self-Determination

Since 1995, sage-grouse (Centrocercus spp.) conservation planning in the western United States has largely been based upon local working groups comprised of federal, state and local governments, environmental groups, landowners, interested citizens. In this article, we review the history and process of these local working groups in western Colorado. These groups are generally convened by one or more government agencies, operate on the general principle of consensus, and have little or no administrative or financial support. The local working groups were generally comprised of field biologist, rancher/landowners, members of local environmental groups and occasionally representatives from local governments. The plans they generated were based upon consensus, therefore difficult issues were often bypassed in order to keep the plan development process moving. The early success of a number of these local working groups resulted in sage-grouse conservation plans such as the Gunnison Sage-grouse Conservation Plan, which provides sage-grouse conservation guidance for the Gunnison Basin in South Central Colorado. However, there were problems such as an undefined membership, lack of administrative support, and achieving consensus. The Gunnison County Board of County Commissioners (BoCC) created an entirely new approach to the local work group concept. The Gunnison Basin Sage-grouse Strategic Committee (GBSGSC) was created, with appointed (by the BoCC) representatives from the federal land management agencies, the state wildlife agency, the neighboring county, the ranching community, the environmental community, the development community, the recreation community, and the public at large. Formal operating guidelines were adopted by the BoCC. Specific membership criteria were identified. Administrative staff from Gunnison County was assigned to the Committee. Importantly, the BoCC determined that, though consensus was an admirable goal, this Committee would operate under majority rule. The GBSGSC has been meeting monthly since 2005

Western corn rootworm pyrethroid resistance confirmed by aerial application simulations of commercial insecticides

The western corn rootworm (Diabrotica virgifera virgifera LeConte) (WCR) is a major insect pest of corn (Zea mays L.) in the United States (US) and is highly adaptable to multiple management tactics. A low level of WCR field-evolved resistance to pyrethroid insecticides has been confirmed in the US western Corn Belt by laboratory dose-response bioassays. Further investigation has identified detoxification enzymes as a potential part of the WCR resistance mechanism, which could affect the performance of insecticides that are structurally related to pyrethroids, such as organophosphates. Thus, the responses of pyrethroid-resistant and -susceptible WCR populations to the commonly used pyrethroid bifenthrin and organophosphate dimethoate were compared in active ingredient bioassays. Results revealed a relatively low level of WCR resistance to both active ingredients. Therefore, a simulated aerial application bioassay technique was developed to evaluate how the estimated resistance levels would affect performance of registered rates of formulated products. The simulated aerial application technique confirmed pyrethroid resistance to formulated rates of bifenthrin whereas formulated dimethoate provided optimal control. Results suggest that the relationship between levels of resistance observed in dose-response bioassays and actual efficacy of formulated product needs to be further explored to understand the practical implications of resistance

Bifenthrin Baseline Susceptibility and Evaluation of Simulated Aerial Applications in \u3ci\u3eStriacosta albicosta\u3c/i\u3e (Lepidoptera: Noctuidae)

Striacosta albicosta (Smith) is a maize pest that has recently expanded its geographical range into the eastern United States and southeastern Canada. Aerial application of pyrethroids, such as bifenthrin, has been a major practice adopted to manage this pest. Reports of field failure of pyrethroids have increased since 2013. Striacosta albicosta populations were collected in 2016 and 2017 from maize fields in Nebraska, Kansas, and Canada and screened with bifenthrin active ingredient in larval contact dose-response bioassays. Resistance ratios estimated were generally low in 2016 (1.04- to 1.32-fold) with the highest LC50 in North Platte, NE (66.10 ng/cm2) and lowest in Scottsbluff, NE (50.10 ng/cm2). In 2017, O’Neill, NE showed the highest LC50 (100.66 ng/cm2) and Delhi, Canada exhibited the lowest (6.33 ng/cm2), resulting in a resistance ratio variation of 6.02- to 15.90-fold. Implications of bifenthrin resistance levels were further investigated by aerial application simulations. Experiments were conducted with a spray chamber where representative S. albicosta populations were exposed to labeled rates of a commercial bifenthrin formulation. Experiments resulted in 100% mortality for all populations, instars, insecticide rates, and carrier volumes, suggesting that levels of resistance estimated for bifenthrin active ingredient did not seem to impact the efficacy of the correspondent commercial product under controlled conditions. Results obtained from this research indicate that control failures reported in Nebraska could be associated with factors other than insecticide resistance, such as issues with the application technique, environmental conditions during and/or after application, or the insect’s natural behavior. Data generated will assist future S. albicosta resistance management programs

Effect of Moisture Content on Dust-Layer Dispersion Behind a Moving Shock Wave

PresentationSecondary dust explosions in coal mines or industrial settings are known to cause greater catastrophic hazards than the coupled primary explosions themselves. The shock waves produced during a primary explosion, which are initiated by inadvertent stimuli in an explosive atmosphere such as methane, lift surrounding coal particles from neighboring areas, and if added in an effort to create an inert mixture, limestone as well. This experimental study works with limestone dust, as its density is close to that of coal particles and its likely presence in the hazardous environment. The current study explored limestone moisture content to understand its effect on dust dispersion, which ultimately can influence the severity of a secondary explosion. A shock tube modified to evaluate dust dispersion provides the optical access to characterize the shock- wave / dust-layer interaction. Based on three shock Mach numbers, namely Ms = 1.1, 1.23, and 1.4, the trending data show an average increase of 10% in overall lifting heights and 20% in initial linear growth rates for the moisture-reduced, dried samples, as compared to undried samples stored in standard temperature and pressure (STP) conditions. Conceivably, the effective moisture reduction in the samples led to fewer agglomerations and/or reduced densities, influencing the ability of lift forces to act on the particles. The quantification of weight loss and weight differences between dried and undried samples was compared. The dust-layer rise height was measured with respect to time after the shock passage, where regardless of moisture content in the samples, initial dust growth rates increased with Mach number. Laminar and unstable regimes were also identified in the data samples, as seen in previous studies by the authors

Polarization mode dispersion compensator field trial and field fiber characterization

Two high-PMD long distance routes were characterized and used to test an optical polarization mode dispersion compensator (PMDC) under field conditions. For this trial, 110 km routes with mean PMD values of 25 and 26.5 ps were provisioned with commercial WDM transport equipment and tested for several weeks. The route was comprised of three spans of characterized fiber that followed railroad tracks. We show the temporal variation of the output polarization state and the evolution of first- and second-order PMD spectra over 7 days. The deployment of a variable-length PMDC on these links allowed error-free transmission of an OC-192 signal. Splitting the output to receivers with and without PMDC demonstrated specific PMD events that caused errors in the absence of a PMDC. (C) 2002 Optical Society of America