182 research outputs found

    Nonlinear bird-habitat relationships in managed forests of the Swan Valley Montana

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    Habitat Relationships of Landbirds in the Northern Region, USDA Forest Service

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    A series of first-generation habitat-relationships models for 83 bird species were detected in a 3-year study on point counts conducted in association with the USDA Forest Service\u27s Northern Region Landbird Monitoring Program. The models depict probabilities of detection for each of the bird species on 100-m-radius, 10-minute point counts conducted across a series of major vegetation cover types. Based on these models, some bird species appear to be restricted in their habitat distribution to: (1) postfire, standing-dead forests, (2) relatively uncut, older forests, (3) harvested forest types, (4) marshes, (5) riparian environments, and (6) grasslands and sagebrush. Such restricted distributions highlight the need to provide adequate amounts of these cover types to maintain viable species populations. Many bird species were relatively abundant in harvested forests, suggesting a need for nesting success studies because timber harvesting creates unnatural cover types that may elicit settling responses by species that are programmed to respond to similar naturally occurring cover types. Thus, these unnatural cover types could be acting as ecological traps, where species are being attracted to sites where suitability is relatively poor. These preliminary results demonstrate the utility of a landbird monitoring program, and suggest that agencies such as the Forest Service should consider broadening the indicator species concept to monitor groups of species (such as landbirds and butterflies) that can be easily sampled with a single field method. The list of species covered by this program is indeed large enough and ecologically broad enough to help managers predict and monitor the effects of management activities on almost all the major vegetation types in the region. The detail and region-specific nature of this information can be matched by no other database in existence on landbirds, and the information should prove useful to land managers in planning areas that might consist of alternative cover types

    Ce vent qui nous fouette

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    Il y a plus de 20 ans : les Ă©meutes de 1981 Tout d’abord permettez-moi de revenir Ă  l’analyse des Ă©meutes de 1981 dont les principaux lieux se situaient Ă  Brixton, Moss Side et Toxteth (voir Lea et Young, 1982). Les Ă©meutiers Ă©taient de façon prĂ©dominante des Afro-CaribĂ©ens avec une minoritĂ© blanche significative. Les Ă©meutes furent dirigĂ©es contre la police et s’accompagnĂšrent de pillages de magasins. Une explication seulement en termes de pauvretĂ© Ă©tait insuffisante, dans la mesure oĂč histo..

    Monitoring for Adaptive Management in Coniferous Forests of the Northern Rockies

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    Monitoring can and should be much more than the effort to track population trends; it can be a proactive effort to understand the effects of human activities on bird populations. It should be an integral part of the adaptive management process. With this in mind, the Northern Region Landbird Monitoring Program has a dual focus: (1) to monitor long-term bird population trends, and (2) to study bird-habitat relationships and management effects. By conducting permanent, longterm monitoring transects every other year, we are free to use the intervening years to study the effects of specific management activities. The coordination and funding is in place to achieve an impressive degree of replication in such studies. These alternate-year monitoring efforts have great potential to get managementoriented results into the hands of managers in the short term, so planning can be improved before long-term trends might reveal a problem. We have conducted several such projects, including the effects of partialcut logging in coniferous forests, and the effects of grazing on willow-riparian bird communities. We discuss here another such project that we initiated in 2001, on bird responses to dry-forest restoration in the northern Rockies. Ponderosa pine (Pinus ponderosa) stands have been greatly altered from historical conditions due to logging and fire suppression. Active treatment of ponderosa pine forests to reverse historical trends is a recent management direction involving wellfinanced, regionally coordinated restoration efforts. The widespread distribution and abundance of planned treatments provided a unique opportunity for a controlled research design (with high replication), including pre- and post-treatment surveys. We present some preliminary results and discuss their relevance to adaptive management

    Moral panic and social theory: Beyond the heuristic

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    Copyright @ 2011 by International Sociological Association.Critcher has recently conceptualized moral panic as a heuristic device, or 'ideal type'. While he argues that one still has to look beyond the heuristic, despite a few exceptional studies there has been little utilization of recent developments in social theory in order to look 'beyond moral panic'. Explicating two current critical contributions - the first, drawing from the sociologies of governance and risk; the second, from the process/figurational sociology of Norbert Elias - this article highlights the necessity for the continuous theoretical development of the moral panic concept and illustrates how such development is essential to overcome some of the substantial problems with moral panic research: normativity, temporality and (un) intentionality

    Comparison of bird community indices for riparian restoration planning and monitoring

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    The use of a bird community index that characterizes ecosystem integrity is very attractive to conservation planners and habitat managers, particularly in the absence of any single focal species. In riparian areas of the western USA, several attempts at arriving at a community index signifying a functioning riparian bird community have been made previously, mostly resorting to expert opinions or national conservation rankings for species weights. Because extensive local and regional bird monitoring data were available for Nevada, we were able to develop three different indices that were derived empirically, rather than from expert opinion. We formally examined the use of three species weighting schemes in comparison with simple species richness, using different definitions of riparian species assemblage size, for the purpose of predicting community response to changes in vegetation structure from riparian restoration. For the three indices, species were weighted according to the following criteria: (1) the degree of riparian habitat specialization based on regional data, (2) the relative conservation ranking of landbird species, and (3) the degree to which a species is under-represented compared to the regional species pool for riparian areas. To evaluate the usefulness of these indices for habitat restoration planning and monitoring, we modeled them using habitat variables that are expected to respond to riparian restoration efforts, using data from 64 sampling sites in the Walker River Basin in Nevada and California. We found that none of the species-weighting schemes performed any better as an index for evaluating overall habitat condition than using species richness alone as a community index. Based on our findings, the use of a fairly complete list of 30–35 riparian specialists appears to be the best indicator group for predicting the response of bird communities to the restoration of riparian vegetation

    Comparison of bird community indices for riparian restoration planning and monitoring

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    The use of a bird community index that characterizes ecosystem integrity is very attractive to conservation planners and habitat managers, particularly in the absence of any single focal species. In riparian areas of the western USA, several attempts at arriving at a community index signifying a functioning riparian bird community have been made previously, mostly resorting to expert opinions or national conservation rankings for species weights. Because extensive local and regional bird monitoring data were available for Nevada, we were able to develop three different indices that were derived empirically, rather than from expert opinion. We formally examined the use of three species weighting schemes in comparison with simple species richness, using different definitions of riparian species assemblage size, for the purpose of predicting community response to changes in vegetation structure from riparian restoration. For the three indices, species were weighted according to the following criteria: (1) the degree of riparian habitat specialization based on regional data, (2) the relative conservation ranking of landbird species, and (3) the degree to which a species is under-represented compared to the regional species pool for riparian areas. To evaluate the usefulness of these indices for habitat restoration planning and monitoring, we modeled them using habitat variables that are expected to respond to riparian restoration efforts, using data from 64 sampling sites in the Walker River Basin in Nevada and California. We found that none of the species-weighting schemes performed any better as an index for evaluating overall habitat condition than using species richness alone as a community index. Based on our findings, the use of a fairly complete list of 30–35 riparian specialists appears to be the best indicator group for predicting the response of bird communities to the restoration of riparian vegetation

    A new method to extract and purify DNA from allophanic soils and paleosols, and potential for paleoenvironmental reconstruction and other applications

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    Andisols, developed from late-Quaternary tephra (volcanic ash) deposits and dominated by the nanocrystalline aluminosilicate, allophane, contain large stores of organic matter and are potential reservoirs for DNA. However, DNA recovery from Andisols and other allophane-bearing soils has been difficult and inefficient because of strong chemical bonding between DNA and both allophane and organic matter, and also because much DNA can be encased and physically protected in nanopores in allophane nano/microaggregates. We have therefore developed a new two-step DNA isolation method for allophanic soils and buried paleosols, including those low in clay, which circumvents these problems. The method centres on (1) releasing mainly microbial DNA, and extracellular (unbound) DNA, using an alkaline phosphate buffer (“Rai’s lysis buffer”) that blocks re-adsorption sites on the allophanic materials, and (2) the novel application of acidified ammonium oxalate (Tamm’s reagent) to dissolve the allophane and to release DNA which had been chemically-bound and also which had been protected within nanopores. Ammonium oxalate has not previously been applied to soil DNA extraction. DNA yields up to 44.5 ”g g-1 soil (oven-dry basis) were obtained from three field-moist natural allophanic soil samples from northern New Zealand using this two-step method. Following extraction, we evaluated different DNA purification methods. Gel electrophoresis of the extracted DNA followed by gel purification of the DNA from the agarose gel, despite some DNA loss, was the only purification method that removed sufficient humic material for successful DNA amplification using the polymerase chain reaction (PCR) of multiple gene regions. Sequencing of PCR products obtained from a buried allophanic paleosol at 2.2-m depth on a sandy Holocene tephra yielded endemic and exotic plants that differed from the European grasses growing currently on the soil’s surface. This difference suggests that the DNA extraction method is able to access (paleo)environmental DNA derived from previous vegetation cover. Our DNA extraction and purification method hence may be applied to Andisols and allophane-bearing paleosols, potentially offering a means to isolate paleoenvironmental DNA and thus facilitate reconstruction of past environments in volcanic landscapes, datable using tephrochronology, and also aid biodiversity understanding of andic soils and paleosols
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