The risks and benefits of signalling aggressive motivation: a study of cave-dwelling little blue penguins

Summary Cave-dwelling little blue penguins, Eudyptula minor, use a large repertoire of agonistic displays. Both qualitative and quantitative measures suggested that some displays were more dangerous to perform than others (estimated by the risk of being injured by one's opponent). A lag sequential analysis of interactions indicated a positive relationship between the risks of performing a display and the display's effectiveness (i.e., in deterring opponents). The cost or risk asymmetries that exist between displays may allow opponents to assess how motivated the actor is to secure or defend resources. Thus, high cost displays are more effective because they reveal a willingness to take risks and also place the opponent in a higher risk situation. Communicating in this way can be an evolutionarily stable strategy (ESS) because signalling a strong motivation entails using potentially costly behavior (i.e., there are costs associated with bluffing). Also, displays that were accompanied by calls were more effective in deterring opponents than the same displays performed silently. Calls may highlight the risks being taken by actors; this may be particularly important in nocturnal species like little blue penguins. Aggressive displays could also be used to predict what the actor was and was not likely to do following the performance of the display. Generally, aggressive displays predicted that the actor would escalate to a higher risk behavior if the opponent did not retreat, but that it would use a lower risk behavior if the opponent backed down. However, risk-based displays should be seen as revealing a certain level of motivation at the time of the display and not as a way of describing how great a risk the actor is willing to take following the display. The predictive value of displays appears to be the result of an escalation process which ensures that opponents are deterred by the lowest risk behavior possible.     

Achieving eco-efficiency through design for environment

“Eco-efficiency” is a term that does not yet appear in dictionaries but has already gained considerable force in shaping the environmental policies and practices of leading corporations. The Business Council on Sustainable Development (BCSD) sounded a trumpet call with their 1992 manifesto, “Changing Course.” Due to the credibility of the companies that constitute BCSD's membership—including Dow Chemical, 3M, Northern Telecom, Ciba-Geigy, Volkswagen, Nissan, Mitsubishi, and many others—their message has had a substantial influence on the strategic thinking of company executives around the world, BCSD's concept of eco-efficiency suggests an important link between resource efficiency (which leads to productivity and profitability) and environmental responsibility. Eco-efficiency makes business sense. By eliminating waste and using resources wisely, eco-efficient companies reduce costs and become more competitive. As environmental performance standards become commonplace, eco-efficient companies will be at an advantage for penetrating new markets and increasing their share of existing markets. This article describes the business practices companies are adopting to increase their eco-efficiency and improve their competitive advantage. “Corporations that achieve ever more efficiency while preventing pollution through good housekeeping, materials substitution, cleaner technologies, and cleaner products and that strive for more efficient use and recovery of resources can be called eco-efficient.” Declaration of the Business Council on Sustainable Development, 1992.     

How the public perceives the visual effects of timber harvesting: an evaluation of interest group preferences

A total of 25 scenes representing the five visual quality objectives in the US Department of Agriculture Forest Service visual management system were presented to 18 professional and public interest groups in western Montana. The results indicate that nearly all the groups have similar rank orderings of the scenes in terms of visual preference. However, the groups differ according to the absolute values of their ratings. Most groups were unable, in a statistical sense, to differentiate the scenic quality of areas in the preservation and retention visual quality objectives. Landscape architects tended to rate scenes in a way similar to professional forest management groups.     

Unionization and deprofessionalization: Which conies first?

This paper constitutes a review of the question whether unionization leads to deprofessionalization or whether deprofessionalization occurs first to be followed by union efforts to restore professional Matus to a profession under attack from social, political, and enconomic forces, including the bureaucracy. The evidence mustered from the historical literature appears to support the latter hypothesis, although it is questionable whether a union by itself can return an established profession to its original status prior to deprofessionalization.     

RUNOFF POLLUTION FROM MULTIPLE FAMILY HOUSING1

ABSTRACT: Increasingly, residential development in urbanizing areas is accomplished by large housing projects, composed of clusters of townhouses or garden partments. It is hypothesized that the runoff from such developments should carry more pollution than that from the same number of housing units on separate plots, because the runoff is conveyed directly to drainage channels rather than being drained across lawns and gardens, which may absorb part of the pollutants. In order to evaluate this effect, storm event data were obtained from a planned unit development near Hightstown, N. J., using samples taken every 10 minutes throughout the storm at two different storm sewers. Results show heavy metals pollution about what had been anticipated, in accordance with the hypothesis given above, and BOD ammonia and phosphates higher than predicted. The results are significant for areawide water quality planning in metropolitan areas, where projections of future pollution loadings depends upon the land use.     

Trends in speciated fine particulate matter and visibility across monitoring networks in the Southeastern United States

Trends in fine particulate matter <2.5 microm in diameter (PM2.5) and visibility in the Southeastern United States were evaluated for sites in the Interagency Monitoring of Protected Visual Environments, Speciated Trends Network, and Southeastern Aerosol Research and Characterization Study networks. These analyses are part of the technical assessment by Visibility Improvement-State and Tribal Association of the Southeast (VISTAS), the regional planning organization for the southeastern states, in support of State Implementation Plans for the regional haze rule. At all of the VISTAS IMPROVE sites, ammonium sulfate and organic carbon (OC) are the largest and second largest contributors, respectively, to light extinction on both the 20% haziest and 20% clearest days. Ammonium nitrate, elemental carbon (EC), soils, and coarse particles make comparatively small contributions to PM2.5 mass and light extinction on most days at the Class I areas. At Southern Appalachian sites, the 20% haziest days occur primarily in the late spring to fall, whereas at coastal sites, the 20% haziest days can occur through out the year. Levels of ammonium sulfate in Class I areas are similar to those in nearby urban areas and are generally higher at the interior sites than the coastal sites. Concentrations of OC, ammonium nitrate, and, sometimes, EC, tend to be higher in the urban areas than in nearby Class I areas, although differences in measurement methods complicate comparisons between networks. Results support regional controls of sulfur dioxide for both regional haze and PM2.5 implementation and suggest that controls of local sources of OC, EC, or nitrogen oxides might also be considered for urban areas that are not attaining the annual National Ambient Air Quality Standard for PM2.5.     

Measurement of vapour pressures of Fenitrothion and Matacil

Vapour pressures of Fenitrothion and Matacil were measured using a gas saturation method. Polyurethane foam was used to trap the volatilized materials from sand and glass surfaces, and Porapak Q for trapping materials volatilized from leaf surfaces. The vapour pressures (VP) were linearly related to the reciprocal temperature by the equation: $\text{Log (VP)}\text{= 6.3362 ? (}\text{3197.8}\text{T}\text{)}$ for a sand incorporated with Fenitrothion and $\text{Log (VP)}\text{= 8.8316 ? (}\text{4021.4}\text{T}\text{)}$ for a sand incorporated with Matacil. The greatest vapour loss rates were from sand incorporated with fenitrothion, followed by vapour loss rates from glass surfaces; the least vapour loss rate was from leaf surfaces.     

Using dispersion and mesoscale meteorological models to forecast pollen concentrations

This work describes the results of research into a source-oriented pollen concentration forecasting technique. Tests were conducted using the National Center for Atmospheric Research/ Penn State Fifth Generation Mesoscale Model (MM5), the National Oceanographic and Atmospheric Administration (NOAA) Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT_4) Model combined with the locations of oak trees and their aerial coverage from biogenic emissions land cover database version 3.1 (BELD3). Daily forecasts of pollen concentrations via MM5 and HYSPLIT_4 were made with 30-min increments and tested against 30-min oak pollen data collected by the St. Louis County Department of Health in Clayton, Missouri, for the month of April 2000.Results from these tests show that the combination of MM5 and HYSPLIT_4 with accurate source locations can provide short-term forecasts as indicated by the levels of forecast pollen and actual oak pollen levels, which follow similar profiles for the day. From the 30 individual pollen concentration forecasts, two example forecasts are presented. Additional studies need to be conducted to further validate these results, using an array of pollen collectors. A better understanding of the biology of pollen release is critical to improving these pollen concentration forecasts.