Life history consequences of variation in age at primiparity in northern elephant seals

Summary The age when female northern elephant seals, Mirounga angustirostris, bear their first young varies from 2 to 6 years. At Año Nuevo, California, a group of 77 females, primiparous at age 3, had a lower survivorship rate to each successive year up to age 8 than a group of 98 females that deferred initial pupping until age 4. The difference in survivorship appears to be due to the greater relative energetic costs of gestation and lactation incurred by the earlier breeding females during a period in their development when growth is rapid. An alternate hypothesis for the difference in survivorship — that young primiparous females are in poor condition from birth-is untenable; females that pupped early in life were larger at weaning age (a correlate of condition) than females that were primiparous 1 year later.Models based on the data show that differential survival of seals that vary in age at primiparity has important consequences for population growth and life history strategies. The effect of age at primiparity on the rate of increase of populations varies with colony density and juvenile survivorship. The optimal life history strategy for female elephant seals under most conditions existing today, including those at Ano Nuevo during the study period, is to bear the first offspring at age 4. Primiparity at age 3 is projected to be favored when harem density is very low and weaning success and juvenile survivorship are high; postponement of first breeding to age 5 is expected at high harem densities with intense competition for breeding space. Offprint requests to: B.J. Le Boeuf     

Understanding the return on health, safety and environmental investments

INTRODUCTION: Traditionally, health safety and environmental (HS & E) investments have been viewed as expensive but necessary. HS & E professionals had a difficult task of providing data showing that these investments can also contribute to business success. An ORC task force developed a way for traditional financial analysis methods to be applied to HS & E investments and decisions. METHOD: The result of the task force effort is the software called the ORC Return on Health, Safety and Environmental Investments (ROHSEI), a supporting tool to provide a comprehensive look at health, safety or environmental investment projects and their potential financial impacts. RESULTS: Since its development, more than 200 companies, government agencies, and educational institutions have been trained in the ROHSEI process and software. CONCLUSIONS: HS & E professionals who are able to evaluate and communicate the business value of health, safety and environmental efforts will improve understanding of the impacts HS & E projects and contribute to better decision making by their organizations.     

Preservation of sulfidic waters containing dissolved As(III)

Solutions containing variable concentrations of sulfide (0 to 31 ppm) and arsenite (0.35 to 10 ppm) were subjected to several different preservation treatments. As predicted by equilibrium thermodynamics, at near-neutral pH the experimental solutions were undersaturated with respect to orpiment (As2S3). However, upon acidification to pH 2 with HCl or HNO3, instantaneous precipitation of poorly crystalline As2S3 occurred in sulfidic solutions which resulted in the loss of dissolved arsenite. These results have implications concerning the practice of acidifying water samples containing hydrogen sulfide with HCl or HNO3 for the purpose of preserving total arsenic values. If a near-neutral water sample contains 1 ppm arsenite and as little as 0.4 ppm sulfide, loss of dissolved arsenic will occur upon acidification. An alternative three-step preservation method involving base addition, oxidation, and acidification is proposed and investigated as an appropriate technique for preserving sulfide-bearing aqueous samples for total arsenic.     

Why recycle? A comparison of recycling motivations in four communities

Four Illinois communities with different sociode-mographic compositions and at various stages of planning for solid waste management were surveyed to determine the influence of sociodemographic variables and planning stages on the factors that motivate recycling behavior. A factor analysis of importance ratings of reasons for recycling and for not recycling yielded five factors interpreted as altruism, personal inconvenience, social influences, economic incentives, and household storage. The four communities were shown to be significantly different in multivariate analyses of the five motivational factors. However, attempts to explain these community differences with regression analyses, which predicted the motivational factors with dummy codes for planning stages, a measure of self-reported recycling behavior, and sociodemographic measures were unsatisfactory. Contrary to expectation, the solid waste management planning stages of the cities (curbside pickup, recycling dropoff center, and planning in progress) contributed only very slightly to the prediction of motivational factors for recycling. Community differences were better explained by different underlying motivational structures among the four communities. Altruistic reasons for recycling (e.g., conserving resources) composed the only factor which was similar across the four communities. This factor was also perceived to be the most important reason for recycling by respondents from all four communities. The results of the study supported the notion that convenient, voluntary recycling programs that rely on environmental concern and conscience for motivation are useful approaches to reducing waste.     

Using Bacteriophages in Recycled Water Exposure Assessment Studies

Bacteriophages MS-2 and PRD-1 were used as indicators of human viral behaviour in a series of turf-grass irrigation and washing machine experiments to provide information about the level of human exposure to potential residual enteric viruses in recycled water that can affect health. Results provided evidence to support a potential inadvertent exposure volume of 0.01 ml for recycled water used for machine clothes washing. Results for irrigation experiments showed that a one log reduction in bacteriophage numbers on turf-grass was not achieved under exposure to high solar conditions after 4 h. Experimentation showed that bacteriophages may be usefully employed in exposure assessment studies based on the ease of their enumeration and logistical and cost considerations. In terms of future studies, observed differences in individual bacteriophage characteristics provide a rationale for using multiple viral indicators. However, limitations on the utility of bacteriophage also need to be considered.     

Farmer’s Response to Societal Concerns About Farm Animal Welfare: The Case of Mulesing

The study explored the motivations behind Australian wool producers’ intentions regarding mulesing; a surgical procedure that will be voluntarily phased out after 2010, following retailer boycotts led by People for the Ethical Treatment of Animals. Telephone interviews were conducted with 22 West Australian wool producers and consultants to elicit their behavioral, normative and control beliefs about mulesing and alternative methods of breech strike prevention. Results indicate that approximately half the interviewees intend to continue mulesing, despite attitudes toward the act of mulesing being quite negative. This indicates that attitudes alone are unlikely to be good predictors of this goal directed behavior. Most respondents believed mulesing was more effective and involved less cost, time, and effort than the currently available alternatives to prevent breech strike. Further, they felt relatively little social pressure, as they believed few consumers were concerned about mulesing. However, they noted that if consumer sentiment changed they would likely change their practices. Thus, attitudes are likely to be only one of several factors influencing intentions to change farm practices to address societal concerns about animal welfare. Further, mulesing appears to be goal-directed behavior, suggesting that other factors depicted by the Model of Goal-directed Behavior (MGB; Perugini and Bagozzi In: Br J Soc Psychol, 40: 79–98, 2001) may be worth exploring in this context. Finally, these results provide insight into how policy makers may influence farmers to change practices in response to societal pressure for improving farm animal welfare.     

Analysis of accidents and incidents occurring during transport of packaged dangerous goods by sea

The release of packaged or containerized dangerous goods during transport can have serious consequences on board a ship. This study was focused on identifying factors contributing to these types of releases and on investigating the contribution of dangerous goods accidents to overall container ship accident rates. Records of dangerous goods releases from a US and a UK database for an 11-year period covering 1998–2008 were analyzed to identify and categorize main contributing factors. The majority of releases, estimated as 97% of the US events and 94% of the UK events, did not follow another primary accident type such as a collision. Faults that occurred during activities such as preparation of the goods for transport, packaging, stuffing containers, and loading the ship were main factors contributing to the release of the dangerous goods on board the ship. For container ship casualties occurring worldwide during the same period, 1998–2008, accidents involving packaged dangerous goods were estimated to account for 15% of all fatalities. Self-ignition or ignition of incorrectly declared dangerous goods was identified as a contributing factor for the fatal accidents. Ensuring that dangerous goods are correctly prepared and documented for marine transport is thus very important for preventing releases and improving on board safety.     

Food contamination as a pathway for lead exposure in children during the 2010–2013 lead poisoning epidemic in Zamfara, Nigeria

In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. The contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children's blood lead levels(BLLs). A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32 mg/kg and 0.85 mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78 μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%–34% of children's BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted.