29 research outputs found

    Evaporative water loss from birds: Effects of artificial radiation

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    1. 1. Metabolism (Vo2) and evaporative water loss (mwe) were measured in black, male Lark Buntings (Calamospiza melanocorys) at 10, 30 and 35[deg]C with and without supplemental radiation (simulating sunlight).2. 2. Vo2 was reduced by radiation at 10[deg]C but not 30[deg] or 35[deg]C.3. 3. mwe was unaffected by radiation at 10[deg]C, however; it was increased 36% at 30[deg]C and 150% at 35[deg]C.4. 4. I suggest caution should be used in arguing the selective advantages of black pigmentation in environments with incident radiation, for although there may be an energy saving at low ambient temperatures, there is a considerable increase in water loss at high ambient temperatures.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23741/1/0000713.pd

    Elk Use of Wallows and Potential Chronic Wasting Disease Transmission

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    Deposition of prions into the environment by infected animals may contribute to transmission and spread of chronic wasting disease (CWD) among free-ranging cervids, and identification of such environmental sources may provide an avenue for managing CWD. We evaluated the role that wallow use by elk (Cervus elaphus) may play in CWD transmission by monitoring wallows with animal-activated cameras throughout their period of use. We monitored 39 wallows from 5 August 2005 to 14 October 2005. Elk visited 20 sites; we recorded 22 events when only male elk wallowed and 374 additional events when male and female elk had naso-oral contact with wallow contents. Because wallows are foci of male elk activity, behaviors at wallows could potentially contribute to the maintenance and transmission of CWD. Our findings, however, suggest that because wallows are only used an average of one or two times a season they may not be important in CWD transmission. The data also suggest that mineral licks could be more important in CWD transmission because they were used more frequently and by three species that contract CWD

    Managing the Miombo woodlands of Southern Africa: policies, incentives and options for the rural poor

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    Miombo woodlands cover vast areas of southern Africa. Of comparatively little interest for export-oriented commercial logging, they are part of a complex system of rural land use that integrates woodland management with crops and livestock. There is also evidence that woodland resources are extensively used for household consumption, greatly reducing the risk of households falling deeper into poverty as a result of environmental or economic stress. New opportunities for improving the management of miombo woodlands, with poverty mitigation in mind, suggest four policy options. First, communities are becoming more active in managing local natural resources, a result of decentralization and land reforms, which suggests that there may be good scope for strengthening related policy and legal frameworks and the measures to implement them. Second, new and integrated conservation-development approaches are emerging, which suggests possible scope for providing payments for environmental services to increase the value of managed woodlands. Third, markets throughout the region are developing and expanding, which suggests great scope for enhancing forest- based markets by removing restrictive legislation and by supporting local producers and forest enterprises. Fourth, all these opportunities suggest that public forest institutions can be revitalized by strengthening their service delivery orientations, with poverty mitigation as a main objective

    Mineral licks: motivational factors for visitation and accompanying disease risk at communal use sites of elk and deer

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    Free-ranging cervids acquire most of their essential minerals through forage consumption, though occasionally seek other sources to account for seasonal mineral deficiencies. Mineral sources occur as natural geological deposits (i.e., licks) or as anthropogenic mineral supplements. In both scenarios, these sources commonly serve as focal sites for visitation. We monitored 11 licks in Rocky Mountain National Park, north-central Colorado, using trail cameras to quantify daily visitation indices (DVI) and soil consumption indices (SCI) for Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) during summer 2006 and documented elk, mule deer, and moose (Alces alces) visiting licks. Additionally, soil samples were collected, and mineral concentrations were compared to discern levels that explain rates of visitation. Relationships between response variables; DVI and SCI, and explanatory variables; elevation class, moisture class, period of study, and concentrations of minerals were examined. We found that DVI and SCI were greatest at two wet, low-elevation licks exhibiting relatively high concentrations of manganese and sodium. Because cervids are known to seek Na from soils, we suggest our observed association of Mn with DVI and SCI was a likely consequence of deer and elk seeking supplemental dietary Na. Additionally, highly utilized licks such as these provide an area of concentrated cervid occupation and interaction, thus increasing risk for environmental transmission of infectious pathogens such as chronic wasting disease, which has been shown to be shed in the saliva, urine, and feces of infected cervids

    When donors get cold feet: the community conservation concession in Setulang (Kalimantan, Indonesia) that never happened

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    There is consensus that payments for biodiversity services are a promising conservation tool, yet the implementation of applied schemes has been lagging behind. This paper explores some reasons why potential biodiversity buyers may hesitate. It describes the case of an unsuccessful attempt to establish a community conservation concession in the village of Setulang (East Kalimantan, Indonesia) to safeguard a biologically valuable area from predatory logging. Potential biodiversity donors did not engage in this payments-for-environmental-services scheme mainly because of their limited time horizon and uneasiness about the conditionality principle. Other complicating factors included overlapping land claims, and the diagnosis of the externality at hand. We conclude that new investment modalities and attitudes are needed if potential biodiversity buyers are to exploit the advantages of this innovative tool. We also provide some tangible recommendations on factors to consider when designing a compensation scheme for conservation at the community level
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