Forage and rangeland plants from uranium mine soils: long-term hazard to herbivores and livestock?

Metalliferous uranium mine overburden soils integrated into arable land or stabilized by perennial rangeland plants evoke concern about the quality of crops and the exposure of grazing and thereby soil-ingesting (wildlife) herbivores to heavy metals (HM) and radionuclides. In a 2-year trial, thirteen annual and perennial forage and rangeland plants were thus potted on, or taken from, cultivated field soil of a metalliferous hot spot near Ronneburg (Germany). The content of soil and shoot tissues in 20 minerals was determined by ICP-MS to estimate HM (and uranium) toxicities to grazing animals and the plants themselves, and to calculate the long-term persistence of the metal toxicants (soil clean-up times) from the annual uptake rates of the plants. On Ronneburg soil elevated in As, Cd, Cu, Mn, Pb, U, and Zn, the shoot mineral content of all test plants remained preferentially in the range of “normal plant concentrations” but reached up to the fourfold to sixfold in Mn, Ni, and Zn, the 1.45- to 21.5-fold of the forage legislative limit in Cd, and the 10- to 180-fold of common herb concentrations in U. Shoot and the calculated root concentrations in Cd, Cu, Ni, and Zn accounted for phytotoxic effects at least to grasses and cereals. Based on WHO PTWI values for the tolerable weekly human Cd and Pb intake, the expanded Cd and Pb limits for forage, and reported rates of hay, roots, and adhering-soil ingestion, the tolerable daily intake rates of 0.65/11.6 mg in Cd/Pb by a 65 kg herbivore would be surpassed by the 11- to 27/0.7- to 4.7-fold across the year, with drastic consequences for winter-grazing and thereby high rates of roots and soil-ingesting animals. The daily intake of 5.3–31.5 mg of the alpha radiation emitter, U, may be less disastrous to short-lived herbivores. The annual phytoextraction rates of critical HM by the tested excluder crops indicate that hundreds to thousands of years are necessary to halve the HM and (long-lived) radionuclide load of Ronneburg soil, provided the herbage is harvested at all. It is concluded that the content in Cd/As, Cd, and Cu exclude herbage/Ronneburg soil from the commercial use as forage or pasture land soil for incalculable time spans. Caution is required, too, with the consumption of game.     

Golden Eagle fatalities and the continental‐scale consequences of local wind‐energy generation

Renewable energy production is expanding rapidly despite mostly unknown environmental effects on wildlife and habitats. We used genetic and stable isotope data collected from Golden Eagles (Aquila chrysaetos) killed at the Altamont Pass Wind Resource Area (APWRA) in California in demographic models to test hypotheses about the geographic extent and demographic consequences of fatalities caused by renewable energy facilities. Geospatial analyses of δ²H values obtained from feathers showed that ≥25% of these APWRA‐killed eagles were recent immigrants to the population, most from long distances away (>100 km). Data from nuclear genes indicated this subset of immigrant eagles was genetically similar to birds identified as locals from the δ²H data. Demographic models implied that in the face of this mortality, the apparent stability of the local Golden Eagle population was maintained by continental‐scale immigration. These analyses demonstrate that ecosystem management decisions concerning the effects of local‐scale renewable energy can have continental‐scale consequences.     

Social Contexts and Customary Fisheries: Marine Protected Areas and Indigenous Use,Australia

Worldwide, the implementation of marine protected areas (MPAs) offers opportunities for delivering fisheries and biodiversity management objectives. In Australia however, the primary function of an MPA is that of biodiversity conservation. Nonetheless, the management of Indigenous customary fisheries is one area where fisheries and biodiversity issues converge. This article examines the relationship between biodiversity and customary fisheries in an MPA context by investigation of the role and importance of Indigenous social contexts. Using case study examples from Australia, I explore the role of Indigenous social contexts in two dimensions: (i) management of traditional fisheries and (ii) Indigenous contribution to fisheries within an MPA. Findings demonstrate two narratives concerning social contexts, one of recognition and the other concerning Indigenous involvement in management. I conclude with a survey of Indigenous management initiatives within MPAs. The article ends with a discussion of the utility of understanding social contexts in any marine management endeavour, specifically other social contexts within an MPA.     

Improving public understanding of environmental issues through effective communication

A lack of understanding about the environmental implications of a proposed project may cause the public to perceive a risk of inflated value and, ultimately, bring the project to a complete and permanent standstill. The authors outline an approach to public education and involvement that focuses on two-way communication and promotes the development of acceptable solutions to critical environmental issues.     

Aversive and avoidance responses of female mice to the odors of males infected with an ectoparasite and the effects of prior familiarity

The detection and avoidance of parasitized males is a component of female mate choice. Here we show that female mice can distinguish between the odors of individual males infected with an ectoparasite, the murine louse, Polyplax serrata, and uninfected males. Female mice displayed aversive responses to, and avoided the odors of, parasitized males. A 15 min exposure to the urinary odors of infected males induced an endogenous opioid-peptide-mediated reduction in pain sensitivity or analgesia, while a brief 1 min exposure to the odors elicited a non-opioid-mediated analgesic response. These neuromodulatory mechanisms facilitate the expression of a variety of anxiety and stress associated responses of which pain inhibition is one component. Females further distinguished between novel and familiar infected males. Prior exposure to the odors of an infected males reduced the degree of analgesia expressed and the associated levels of anxiety and stress and their concomitant costs. In a Y-maze odor preference test females also displayed a marked overall preference for, and initial choice of, the odors of clean, uninfected males and an active discrimination against, and avoidance of, the odors of both familiar and novel infected males. These findings indicate that female mice can distinguish between males infected with an ectoparasite and clean uninfected males and display aversive and avoidance responses to infected males. They also show that females can discriminate between individual infected males and modulate their aversive responses to the odors of infected males on the basis of prior familiarity. This is likely part of the mechanisms whereby females can both reduce the transmission of ectoparasites, such as lice, to themselves and select for parasite-free males.     

Feather-like development of Triassic diapsid skin appendages

Of the recent sauropsid skin appendage types, only feathers develop from a cylindrical epidermal invagination, the follicle, and show hierarchical branching. Fossilized integuments of Mesozoic diapsids have been interpreted as follicular and potential feather homologues, an idea particularly controversially discussed for the elongate dorsal skin projections of the small diapsid Longisquama insignis from the Triassic of Kyrgyzstan. Based on new finds and their comparison with the type material, we show that Longisquama's appendages consist of a single-branched internal frame enclosed by a flexible outer membrane. Not supporting a categorization either as feathers or as scales, our analysis demonstrates that the Longisquama appendages formed in a two-stage, feather-like developmental process, representing an unusual early example for the evolutionary plasticity of sauropsid integument.     

Rapid matching in Drosophila place learning

The level of conditioned behavior in animals is proportional to the intensity, amount, frequency, or probability of reinforcement. Interestingly, this matching can be dynamic, with performance levels following, for example, a switch in the probability of reinforcement with a short delay. We previously found that conditioned performance levels in Drosophila match reinforcement intensity in a place conditioning paradigm. Whether Drosophila can match conditioned behavior to a change in reinforcement intensity was an open question. In this study, we found that both conditioned behavior and memory levels match reinforcement intensity after a switch, and this rapid matching occurs within 2 min. Thus, fruit flies can dynamically match conditioned behavior and memory levels to a change in reinforcement intensity.     

On the evolutionary significance of the size and planarity of the proline ring

Proline is a proteinogenic amino acid in which the side chain forms a ring, the pyrrolidine ring. This is a five-membered ring made up of four carbons and one nitrogen. Here, we study the evolutionary significance of this ring size. It is shown that the size of the pyrrolidine ring has the advantage of being nearly planar and strain-free, based on a general mathematical assertion saying that the angular sum of a polygon is maximum if it is planar and convex. We also provide a sketch of the proof to this assertion. The optimality of the ring size of proline can be derived from a triangle inequality for angles. Quasi-planarity is physiologically significant because it allows an easier and evolutionarily old type of fit into binding grooves of proteins with which proline-rich proteins interact. Finally, we present a comparison with other planar, nearly planar and non-planar biomolecules such as neurotransmitters, hormones and toxins, involving, for example, aromatic rings, cyclopentanone and 1,3-dioxole.     

Age and growth rates of Hawaiian hawksbill turtles (Eretmochelys imbricata) using skeletochronology

The Hawaiian hawksbill population has fewer than 20 females nesting per year; hence, there is a need to monitor this population closely and basic biological information on individual growth and age to maturity is critical. We present a skeletochronology analysis of Hawaiian hawksbills using humeri recovered from 30 dead stranded hawksbills, plus 10 dead hatchlings. Growth mark morphology shows readily distinguishable marks similar in appearance to other species, though some animals displayed more diffuse marks. Growth rates remained high (average 2.24–4.77 cm year^?1) from 20 to 80 cm straight carapace length (SCL). Hawksbills larger than 80 cm SCL had average growth rates of 0.3 cm year^?1. There were few adult turtles in the sample; however, results indicate hawksbills have faster growth rates than loggerhead or green turtles, with probable average age to maturity (at size 78.6 cm SCL) occurring between 17 and 22 years.     

Interactions between scientific uncertainty and flood management decisions: Two case studies in Colorado

Flood management policies in the United States rely on scientific information about the frequency and intensity of extreme precipitation and runoff. Yet, the available information is inherently uncertain because of the complexity of meteorological and hydrological processes. In mountainous areas, flood risk can vary greatly even within short distances depending on local climate, topography, soil characteristics, and land use. This paper describes two Colorado cases in which policy makers were presented with conflicting scientific estimates: revision of the Fort Collins floodplain map and modification of the Cherry Creek Dam. The case studies demonstrate that uncertainty can have substantial impacts on regulatory processes, public safety, and costs. The analysis considers the differing perspectives of various participants in the flood management processes, illustrating the interplay between uncertainties attributable to scientific issues and values issues. It suggests that attempts to provide a single “best” estimate do not necessarily meet the decision needs of all stakeholders. Conclusions indicate a need to improve communication about uncertainty when scientific estimates areprovided to decision makers. Furthermore, in highly controversial decisions, it may be necessary to reframe the discussion to consider the values issues raised by scientific uncertainty.