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To elucidate ecological effects of variation in the temporal distribution of a limiting resource (water in the Mojave Desert), energetics of two free-living populations of desert tortoises (Gopherus [=Xerobates] agassizii) were studied concurrently over 18 mo with use of doubly-labeled water. Field metabolic rates (FMR) and feeding rates (estimated from rates of water influx and rates of change in dry mass) were highly variable. This variability was manifested at several levels, including seasonal changes within populations, year-to-year differences within populations, and differences between populations. Underlying observed patterns and contrasts was considerable variation among individuals. Much of the variation...
The review provides an overview of the features of the North Sea and the Baltic Sea in their European geographical and socio-political context. To reach sustainability in the wider sense the common society has to meet the 7 tenets - that management actions have to be environmentally sustainable, economically viable, technologically feasible, socially desirable (or at least tolerable), legally permissible, administratively achievable and politically expedient. Each of these are explained and discussed using examples from the two seas including pollution control, physical resource exploitation (such as aggregates, habitat loss, renewable energy and oil and gas), and biological resources exploitation (fisheries and...
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Conclusions: Caribou subpopulation persistence and landscape occupancy depends highly on the degree of forest cover, cover type, and distance from human presence. Thresholds/Learnings: Synopsis: This study evaluates factors influencing the persistence and landscape occupancy of caribou subpopulations in southern British Columbia. Data from 235 radio-collared caribou across 13 subpopulations were used to derive a landscape occupancy index. The index was analyzed against 33 landscape variables including, land cover, terrain, climate, and human influence. At the metapopulation level, the persistence of subpopulations correlated with the extent of wet climate conditions and the distribution of old forests and alpine...
The Utah sucker (Catostomus ardens) is endemic to the Bonneville Basin and the upper Snake River drainage in western North America, and is thought to hybridize with the federally endangered June sucker (Chasmistes liorus mictus) in Utah Lake (Bonneville Basin). Here we describe the discovery of a major subdivision in Utah suckers (4.5% mitochondrial sequence divergence) between the ancient Snake River drainage and the Bonneville Basin. This boundary has not previously been recognized in Utah suckers based on morphologic variation, but has been recently described in two endemic cyprinids in the region. Populations in valleys east of the Wasatch Mountains in Utah clustered with the Snake River populations, suggesting...
Miscanthus is a newly introduced crop grown primarily to produce biomass for energy production and the area grown in the UK is anticipated to increase. Major differences in crop management from conventional arable crops have led to speculation that miscanthus may also have effects on farmland biodiversity. Six miscanthus fields were paired with six of a conventional crop, winter wheat, and bird diversity and abundance were compared in winter and during the breeding season along with potential food sources. Miscanthus fields had a greater abundance and diversity of birds than did wheat in winter and summer. In winter, the greater numbers of birds in miscanthus fields were probably attracted by the shelter provided...
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Conclusions: Caribou demonstrated patterns of avoidance near linear features such as pipelines, roads, and other oil field structures. Females demonstrated heightened avoidance, especially during calving seasons. Thresholds/Learnings: Synopsis: This study documented the behavioural reactions of caribou to oil development in the circumpolar regions of the northern hemisphere. Researchers observed patterns of avoidance near linear features such as pipelines, roads, and other oil field structures. Female caribou, especially those accompanied by calves avoided these areas in particular. Male caribou were more apt to occupy areas influenced by oil field structures and activity. In summary, the patterns oil field development...
Global climatic change is expected to affect growth and survival of trees and will likely change the geographical distribution of many temperate and boreal tree species. Models that calculate the effects of environmental factors, as well as biotic factors, such as intra- and interspecific competition, on growth and survival of trees have been widely used to calculate the potential effects of temperature changes on tree populations. The methods to calculate thermal effects in such models are described and analyzed for the soundness and consistency of underlying assumptions. They are compared to the evidence from studies of tree physiology, growth, and biogeography. The use of thermal indices, especially temperature...
Modification of landscapes due to energy development may alter both habitat use and vital rates of sensitive wildlife species. Greater sage-grouse (Centrocercus urophasianus) in the Powder River Basin (PRB) of Wyoming and Montana, USA, have experienced rapid, widespread changes to their habitat due to recent coal-bed natural gas (CBNG) development. We analyzed lek-count, habitat, and infrastructure data to assess how CBNG development and other landscape features influenced trends in the numbers of male sage-grouse observed and persistence of leks in the PRB. From 2001 to 2005, the number of males observed on leks in CBNG fields declined more rapidly than leks outside of CBNG. Of leks active in 1997 or later, only...
A regularly raised concern for wind farms is the number of species and rate of bird and bat collisions with turbines. Australian regulators require, at some operating wind farms, the monitoring of bird and bat collisions. Although monitoring is becoming more commonplace, the area recommended for searching beneath turbines is inconsistent, with many guidelines both in Australia and overseas being based on conjecture rather than empirical evidence. This has the potential to bias survey results, reduce confidence in the data collected, and preclude meaningful comparisons between sites. By having a measure of the range of the fall zone of a bird or bat, a survey can be designed that ensures that an adequate area is...
The basic principles underlying a four-discrete age group, logistic, growth model for the European lobster Homarus gammarus are presented and discussed at proof-of-concept level. The model considers reproduction, removal by predation, natural death, fishing, radiation and migration. Non-stochastic effects of chronic low linear energy transfer (LET) radiation are modelled with emphasis on Tc-99, using three endpoints: repairable radiation damage, impairment of reproductive ability and, at higher dose rates, mortality. An allometric approach for the calculation of LD50/30 as a function of the mass of each life stage is used in model calibration. The model predicts that at a dose rate of 1 Gy day(-1), lobster population...
The basic principles underlying a four-discrete age group, logistic, growth model for the European lobster Homarus gammarus are presented and discussed at proof-of-concept level. The model considers reproduction, removal by predation, natural death, fishing, radiation and migration. Non-stochastic effects of chronic low linear energy transfer (LET) radiation are modelled with emphasis on Tc-99, using three endpoints: repairable radiation damage, impairment of reproductive ability and, at higher dose rates, mortality. An allometric approach for the calculation of LD50/30 as a function of the mass of each life stage is used in model calibration. The model predicts that at a dose rate of 1 Gy day(-1), lobster population...
We used variation in a portion of the mitochondrial DNA control region to examine phylogeography of Tamiasciurus hudsonicus, a boreal-adapted small mammal in the central Rocky Mountain region. AMOVA revealed that 65.66% of genetic diversity was attributable to variation within populations, 16.93% to variation among populations on different mountain ranges, and 17.41% to variation among populations within mountain ranges. Nested clade analysis revealed two major clades that likely diverged in allopatry during the Pleistocene: a southern clade from southern Colorado and a northern clade comprising northern Colorado, Wyoming, eastern Utah, and eastern Idaho. Historically restricted gene flow as a result of geographic...
U.S. States (Generalized) represents the fifty states and the District of Columbia of the United States. The Northwest Climate Science Center (NW CSC) Science Agenda outlines the overall science direction for the NW CSC in 2012-2016. It forms an integral part of the NW CSC Strategic Plan for 2012-2016 and was developed with input from cultural and natural resource managers in the Northwest. The Science Agenda guides the NW CSC and its Executive Stakeholder Advisory Committee ( ESAC) in the identification of annual and long-term research priorities to be funded by the NW CSC.
Standard of living is determined in part by the availability of ecological resources, and in part by the availability of "cheap energy." The demise of cheap energy is likely to occur during the twenty-first century. Gradually, over this time, humans will be restricted to using renewable natural capital. Reliance on renewable energy sources will require a reduction in population to within the range of 1.5 to 3 billion people in order to maintain what most of us would regard as an adequate lifestyle. Attention is drawn to the need for nations to exercise sovereign responsibility.
Categories: Publication; Types: Citation; Tags: Population, cheap, demise, energy
With electric generation responsible for 41 percent of U.S anthropogenic carbon dioxide (CO2) emissions from energy use, development of clean energy sources is essential if the United States is to reduce release of greenhouse gases and slow global warming. Many proponents of sustainable energy anticipate that electric generation from renewable sources would thrive in a deregulated market, driven by consumer demand for "green" energy and the end of incentives to build large central power plants under the cost-plus profits guaranteed by state utility commissions. This paper examines the flaws in this expectation. After reviewing the highly cyclical nature of U.S. energy policy making in recent decades, the study links...
Categories: Publication; Types: Citation; Tags: Population, cheap, demise, energy
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This dataset provides transboundary census information in the Crown of the Continent Ecosystem. In Canada the data are from the 2011 census collected at the dissemination block level, in the United States the data are assembled from the 2010 census. Data on total population and total dwellings in each census unit are available. This dataset was developed by the Crown Managers Partnership, as part of a transboundary collaborative management initiative for the Crown of the Continent Ecosystem, based on commonly identified management priorities that are relevant at the landscape scale. The CMP is collaborative group of land managers, scientists, and stakeholder in the CCE. For more information on the CMP and its collaborators,...
Recent reintroduction of the black-footed ferret (Mustela nigripes) in west-central South Dakota has focused new attention on black-tailed prairie dogs (Cynomys ludovicianus), because prairie dog colonies provide essential habitat for ferrets. Currently, management agencies are assessing prairie dog populations by counting active burrows, a technique that is attracting criticism. We correlated active and total burrow counts with prairie dog mark-recapture population estimates from 12 colonies located in Badlands National Park and adjacent Buffalo Gap National Grassland. We also correlated visual counts of prairie dogs and counts of mounds from aerial photographs with mark-recapture estimates to assess an alternative...
Implementing conservation in the face of unprecedented landscape change requires an understanding of processes and scales that limit wildlife populations. We assessed landscape-level processes influencing sage-grouse (Centrocercus urophasianus), to a migratory population in the Milk River Basin (MRB), northeast Montana, USA, and south-central Saskatchewan, Canada. A regional analysis of leks (e.g., communal breeding sites) documented that populations impacted by the increasing extent of agricultural tillage, roads, and energy development out to spatial scales larger than previously known. Using bird abundance as a novel way to evaluate human impacts revealed relationships that would have been missed had we not incorporated...
map background search result map search result map Caribou in the Changing North Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Census c2010 Crown of the Continent Ecosystem Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Census c2010 Crown of the Continent Ecosystem Caribou in the Changing North