Egg-mimicry as a mating strategy in the fantail darter,Etheostoma flabellare: females prefer males with eggs

Summary In some species of fishes with paternal care, females prefer to spawn with males already defending eggs. Such female preference appears to have resulted in adoption of unrelated eggs as a male mating strategy in several species. Page and Swofford (1984) proposed that such female preference may have also resulted in the evolution of male egg-mimics in several species of darters (Percidae); however, their hypothesis has not been tested. We examined female preference in the fantail darter (Etheostoma flabellare) and found that females preferred males with eggs over males without eggs, and males with egg-mimics over males without egg-mimics. Thus it appears that female preference for males already guarding eggs may have led to the evolution of specialized egg-mimicking morphology in males.     

INTEGRATING A GEOGRAPHIC INFORMATION SYSTEM,A SCIENTIFIC VISUALIZATION SYSTEM,AND A PRECIPITATION MODEL1

ABSTRACT: Investigating natural, potential, and human-induced impacts on hydrologic systems commonly requires complex modeling with overlapping data requirements, plus massive amounts of one- to four-dimensional data at multiple scales and formats. Given the complexity of most hydrologic studies, the requisite software infrastructure must incorporate many components including simulation modeling and spatial analysis with a flexible, intuitive display. Integrating geographic information systems (GIS) and scientific visualization systems (SVS) provides such an infrastructure. This paper describes an integrated system consisting of an orographic precipitation model, a GIS, and an SVS. The results of this study provide a basis for improving the understanding of hydro-climatic processes in mountainous regions. An additional benefit of the integrated system, the value of which is often underestimated, is the improved ability to communicate model results, leading to a broader understanding of the model assumptions, sensitivities, and conclusions at a management level.     

Improving species status assessments under the U.S. Endangered Species Act and implications for multispecies conservation challenges worldwide

Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline ESA decisions include multispecies recovery plans and habitat conservation plans. We address species status assessment (SSA), a USFWS process to inform ESA decisions from listing to recovery, within the context of multispecies and ecosystem planning. Although existing SSAs have a single-species focus, ecosystem-based research can efficiently inform multiple SSAs within a region and provide a foundation for transition to multispecies SSAs in the future. We considered at-risk grassland species and ecosystems within the southeastern United States, where a disproportionate number of rare and endemic species are associated with grasslands. To initiate our ecosystem-based approach, we used a combined literature-based and structured World Café workshop format to identify science needs for SSAs. Discussions concentrated on 5 categories of threats to grassland species and ecosystems, consistent with recommendations to make shared threats a focus of planning under the ESA: (1) habitat loss, fragmentation, and disruption of functional connectivity; (2) climate change; (3) altered disturbance regimes; (4) invasive species; and (5) localized impacts. For each threat, workshop participants identified science and information needs, including database availability, research priorities, and modeling and mapping needs. Grouping species by habitat and shared threats can make the SSA process and other planning processes for conservation of at-risk species worldwide more efficient and useful. We found a combination of literature review and structured discussion effective for identifying the scientific information and analysis needed to support the development of multiple SSAs. Article impact statement: Species status assessments can be improved by an ecosystem-based approach that groups imperiled species by shared habitats and threats.     

A Transition-Flow Reactor Tube for Measuring Trace Gas Concentrations

Dry deposition contributes significantly to the acidification of ecosystems. However, difficulties in measuring dry deposition of reactive gases and fine particles make routine direct monitoring impractical. An alternate approach is to use the “concentration monitoring” method in which dry deposition flux is estimated as the product of measured concentration and estimated deposition velocity. A sampling system that performs over the period of 6 hours to 7 days, depending on atmospheric concentrations, has been developed. It consists of a Teflon cyclone to exclude particles larger than about 2 μm, selective solid adsorption media for reactive gases—some of which are sampled from a transition flow to avoid possible bias from particle evaporation, a particle filter, and a final gas adsorption filter to collect the remaining trace gas. The sampler Is the first reported application of transition flow mass transfer for the collection and quantitative measurement of trace atmospheric gases. Laboratory and field tests have shown that the sampler performs well for HNO₃(g).     

Formation of deposits on the surfaces of superheaters and economisers of MSW incinerator plants

Mineralogical and chemical investigations of deposits from superheaters and economisers from a MSWI plant in Mannheim, Germany, lead to a classification system which provides information about the most critical parameters leading to fouling and corrosion. With the help of this classification system parameters like the geometry of boilers and the waste input can be changed in order to prolong run times between revisions and enhance energy efficiency of MSWI plants.