Recent trends in ILO conventions related to occupational safety and health.

The present study was conducted to analyze the ratification status of International Labour Organization (ILO) conventions related to occupational safety and health (OSH) by ILO member states in terms of national indicators (length of ILO membership and national income status) and regional affiliation. 17 conventions designated as OSH-related by the 2003 International Labour Conference were examined. In general, countries with longer ILO membership ratified higher numbers of conventions related to OSH. With some variation, long-membership countries had the largest number of ratifications, followed by middle- and short-membership countries in all regions. There were also incremental increases in the number of ratifications for OSH-related conventions according to the national income status. Common regional characteristics that could not be explained by the factors studied also existed. Future efforts to increase ratification at an international level will need to consider the factors influencing ratification practice among the member states.     

RUNOFF EVENT IMPACTS ON A WATER SUPPLY RESERVOIR: SUSPENDED SEDIMENT LOADING, TURBID PLUME BEHAVIOR, AND SEDIMENT DEPOSITION1

Abstract: The impacts of runoff events on external suspended solids loading to Schoharie Reservoir, New York, and patterns of light scattering and sediment deposition in this reservoir are assessed. The assessment is based on monitoring of suspended solids concentrations in the reservoir's primary tributary, detailed vertical profiles of optical backscattering (a surrogate measure of light scattering) in the reservoir water column, and analysis of sediment trap collections, over a seven-month interval of high runoff. These impacts are reported to be tightly temporally coupled and strongly positively related to the magnitude of runoff events. The primary tributary entered the reservoir as a plunging inflow during runoff events, causing conspicuous subsurface peaks in light scattering, with vertical patterns that varied strongly for different events. Deposition quantified by near-bottom trap deployments is reported to be more representative than results from metalimnetic deployments that were generally within, rather than below, the turbid layers. Direct inputs of sediment, transported by density currents, are found to drive deposition, rather than resuspension/redeposition. More than 50 percent of the reported deposition occurred in less than 15 percent of the study period, associated with the four largest runoff events.     

Sex differences in maternal investment by Macaca mulatta

Summary The possibility that male offspring are more costly to produce than female offspring was investigated in captive Macaca mulatta. Differential maternal investment into 187 infants was evaluated by comparing birth weight, infant growth rate, month of birth, and interbirth interval of males and females. There were no statistically significant differences between male and female infants for any of these variables.     

Female nutritional state affects the rate of male incubation feeding in the pied flycatcher Ficedula hypoleuca

Summary Male pied flycatches Ficedula hypoleuca regularly feed their mates during incubation. By experimentally supplying some females with extra food we studied how the female's nutritional state affected her incubation schedule and the rate at which her mate fed her. Females that received extra food spent more time on the nest and shorter periods away from it, compared with control females. This suggests that nest attentiveness is governed by the amount of energy available to the female. When females reccived extra food, males decreased their rate of incubation feeding. They also did so in response to increasing ambient temperatures, whereas incubation schedules were unaffected. We, therefore, conclude that our results support the female nutrition hypothesis, i.e., that the food provided by the male constitutes a significant nutritional contribution to the incubating female.     

Behavioral aspects of competition in a three-species rodent guild of coastal southern California

Summary The influence of vole cycles on the demography, spatial organization, and abundance of potential rodent competitors was studied in three California rodents in the laboratory and in the field. Population densities ofMicrotus californicus were inversely correlated with reproductive success in two potential competitors (Reithrodontomys megalotis andMus musculus). Additionally, high-density vole populations forced these species into suboptimal habitats. During low-density vole populations,Reithrodontomys andMus left their refugia, expanded their usage of habitat, were more active, and their reproductive success was greater. Thus, this work suggests that during vole population peaks, competition with sympatric species of mice is severe. Conversely, when vole populations decline, competition is relaxed. The temporal and spatial organization of the three-species complex supports models of nonequilibrium and fugitive species coexistence.     

In vivo marking of shallow-water and deep-sea amphipods by ingestion of bait mixed with fast green

Seven vital stains were mixed with fish muscle and fed to a sublittoral lysianassid (Orchomene sp. A collected in Scripps Canyon off La Jolla, California USA between August 1978 and August 1981) in the laboratory to test the utility of these dyes as feeding labels for scavenging amphipods. Fast-green FCF proved to be the most effective of the stains tested; >90% of starved amphipods fed fast-green-stained bait (Scomber japonicus muscle) for as little as 1 h exhibited a conspicuous green coloration along the digestive tract, which lasted an average of 35 d. The ability to label animals with such a single, short exposure interval makes this dye especially suitable for marking scavengers attracted to bait. Fast green efficiently stained this amphipod over a broad range of concentrations (1 to 8% by weight in water) and feeding regimes, and had no significant effects on survivorship or activity of laboratory-held organisms. Nile blue A also proved to be an acceptable feeding label for Orchomene sp. A for time scales of about 1 wk. Additional laboratory and field tests between August 1978 and August 1979 indicated that fast green is an effective feeding stain for 2 bathyal species (Orchomene sp. B and O. plebs from the Ross Sea, Antarctica) and 3 abyssal species (Eurythenes gryllus, O. gerulicorbis and Paralicella caperesca from the central North Pacific Ocean) of amphipods. Field labeling of amphipods at 5 800 m in the central North Pacific Ocean with fast green demonstrates that feeding stains may be used readily as in situ marking agents for population studies of scavengers in remote environments.