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A variety of community and external pressures on Indigenous Peoples are leading to increased use of food that is available through industrialization and market economies; food in traditional food systems derived from local, natural environments is declining in use. This report focusses on dietary intake of Arctic men. While nutrient density of Arctic traditional food systems is superior to that of the composite of market food consumed in the North, the percentage of men's daily energy derived from market food is more than double that from traditional food in some communities. Older members of communities consume more traditional food than younger members; men consume more traditional food than do women. In addition...
Forests are important in the global carbon cycle, forming a major sink for carbon. Deforestation is a significant source of carbon dioxide emitted to the atmosphere. There is some scope to enhance natural carbon sinks, and therefore reduce net emissions of greenhouse gases, through afforestation and conservation of existing forests. Such initiatives may be implemented to "offset" emissions of greenhouse gases from other sources. This may be undertaken by private companies, or by governments as part of bilateral agreements or multilateral arrangements. International carbon offsets may be cost effective in terms of reduction of carbon emissions achieved, and may also be one way to mobilise private capital to fund...
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In this observational pilot study, we worked at the largest existing solar tower facility in the world (Ivanpah Solar Electric Generating System - ISEGS) to assess the efficacy of using radar, surveillance video, and insect trapping to monitor animals flying near the towers. During week-long site visits in May and September, we monitored the airspace surrounding towers and observed insects, occasional birds, and bats under a variety of environmental and operational conditions. This dataset enumerates invertebrates captured using both malaise and funnel traps placed on the ground in the immediate vicinity of solar towers in the locations shown in Figure 2 of the associated paper. The locational information below...
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In this observational pilot study, we worked at the largest existing solar tower facility in the world (Ivanpah Solar Electric Generating System - ISEGS) to assess the efficacy of using radar, surveillance video, and insect trapping to monitor animals flying near the towers. During week-long site visits in May and September, we monitored the airspace surrounding towers and observed insects, occasional birds, and bats under a variety of environmental and operational conditions. This dataset consists of raster portable network graphics (png) images of the planned position indicator (ppi) display from a Furuno FR2127 portable radar unit to a maximum range of 1.5 km. A new image is written with each rotation of the...
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These bat location estimates have been reported by Bogan and others (In press) and come in the form of a GIS shape file. Three species of nectar-feeding phyllostomid bats migrate north from Mexico into deserts of the United States (U.S.) each spring and summer to feed on blooms of columnar cacti and century plants (Agave spp). However, the habitat needs of these important desert pollinators are poorly understood. We followed the nighttime movements of two species of long-nosed bats (Leptonycteris yerbabuenae and L. nivalis) in an area of late-summer sympatry at the northern edges of their migratory ranges. We radiotracked bats in extreme southwestern New Mexico during 22 nights over two summers and acquired location...
The rate of future climate change is likely to exceed the migration rates of most plant species. The replacement of dominant species by locally rare species may require decades, and extinctions may occur when plant species cannot migrate fast enough to escape the consequences of climate change. Such lags may impair ecosystem services, such as carbon sequestration and clean water production. Thus, to assess global change, simulation of plant migration and local vegetation change by dynamic global vegetation models (DGVMs) is critical, yet fraught with challenges. Global vegetation models cannot simulate all species, necessitating their aggregation into plant functional types (PFTs). Yet most PFTs encompass the full...
Twelve wild adult Colorado pikeminnow (Ptychocheilus lucius), captured in the tailwaters of Taylor Draw Dam on the White River, Colorado, were implanted with radio transmitters and their movement patterns monitored from 1992 to 1994. The spawning migration of these fish was extensive. In 1993, the only full year of the study, the fish migrated an average of 658 km from the White River to spawning sites in the Yampa or Green rivers and back to the White River. Eight of these fish were translocated in the river upstream of the dam in April 1993. These fish and the 4 others below the dam remained in the river until May 1993. All 12 had migrated down the White River to spawning sites in the Green and Yampa rivers by...
Present power markets are designed for trading conventional generation. For wind generation to participate in a short-term energy market, lengthy wind power production forecasts are required. Although wind speed forecasting techniques are constantly improving, wind speed forecasts are never perfect, and resulting wind power forecast errors imply imbalance costs for wind farm owners. In this paper, a new method for minimization of imbalance costs is developed. Stochastic programming is used to generate optimal wind power production bids for a short-term power market. A Wind power forecast error is represented as a stochastic process. The imbalance costs resulting from this strategy are then compared to the case when...
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In this observational pilot study, we worked at the largest existing solar tower facility in the world (Ivanpah Solar Electric Generating System - ISEGS) to assess the efficacy of using radar, surveillance video, and insect trapping to monitor animals flying near the towers. During week-long site visits in May and September, we monitored the airspace surrounding towers and observed insects, occasional birds, and bats under a variety of environmental and operational conditions. This dataset is comprised of the unedited digital video imagery we gathered during those site visits. There are four types of video imagery included in the data set: (1) "EMCCD camera" is the output of an electron multiplying charge-coupled-device...
Forests are important in the global carbon cycle, forming a major sink for carbon. Deforestation is a significant source of carbon dioxide emitted to the atmosphere. There is some scope to enhance natural carbon sinks, and therefore reduce net emissions of greenhouse gases, through afforestation and conservation of existing forests. Such initiatives may be implemented to "offset" emissions of greenhouse gases from other sources. This may be undertaken by private companies, or by governments as part of bilateral agreements or multilateral arrangements. International carbon offsets may be cost effective in terms of reduction of carbon emissions achieved, and may also be one way to mobilise private capital to fund...
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The Green Wave Hypothesis posits that herbivore migration manifests in response to waves of spring green-up (i.e., green-wave surfing). Nonetheless, empirical support for the Green Wave Hypothesis is mixed, and a framework for understanding variation in surfing is lacking. In a population of migratory mule deer (Odocoileus hemionus), 31% surfed plant phenology in spring as well as a theoretically perfect surfer, and 98% surfed better than random. Green-wave surfing varied among individuals, and was unrelated to age or energetic state. Instead, the greenscape, which we define as the order, rate, and duration of green-up along migratory routes, was the primary factor influencing surfing. Our results indicate that...
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Natural river channels continually evolve and change shape over time. As a result, channel evolution or migration can cause problems for bridge structures that are fixed in the flood plain. A once-stable bridge structure that was uninfluenced by a river’s shape could be encroached upon by a migrating river channel. The potential effect of the actively meandering Wabash River on the Interstate 64 (I–64) Bridge at the border with Indiana near Grayville, Illinois, was studied using a river migration model called RVR Meander (RVR Meander, 2011). RVR Meander is a toolbox that can be used to model river channel meander migration with physically based bank erosion methods. This study assesses the Wabash River meandering...
Little is known regarding the migratory behavior of bats, due in part to their elusive nature. Recently, however, fatalities of migratory bats at some wind energy facilities across North America have provided the opportunity and impetus to study bat migration at the landscape level. Using acoustic monitoring and carcass searches, we examined variation in activity levels and fatality rates of bats across southern Alberta, Canada, to determine if bat activity and fatality are concentrated in certain areas or evenly distributed across the landscape. To investigate geographical variation in bat activity, we acoustically monitored activity from 15 July to 15 September 2006 and 2007 at 7 proposed or existing wind energy...
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The tabular dataset is a compilation of all historic observations of whooping crane locations up through 1941. Most of the records were obtained from Robert Porter Allen's 1952 report, "The Whooping Crane"; an additional 73 records were added from records found since 1952. Records include source (Allen 1952 [The Whooping Crane, Audubon]or other), location name, county, state or province, country (Canada, US, Mexico), estimated latitude and longitude, year, month, day, life stage (breeding, summering, wintering, migration, unknown), season (spring, summer, fall, winter), observer's name, and logical indicators of nesting, specimen taken, observer identified, or if captive bird. Completeness of each record is variable....
1. Wind power plants represent a risk of bird mortality, but the effects are still poorly quantified. We measured bird mortality, analysed the factors that led birds to fly close to turbines, and proposed mitigation measures at two wind farms installed in the Straits of Gibraltar, one of the most important migration bottlenecks between Europe and Africa. 2. Bird corpses were surveyed along turbine lines and an associated power line to estimate mortality rates. The behaviour of birds observed within 250 m of turbines was also recorded as a putative indicator of risk. The effects of location, weather and flight behaviour on risk situations (passes within 5 m of turbines) were analysed using generalized linear modelling...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1111/ele.12772/full): The Green Wave Hypothesis posits that herbivore migration manifests in response to waves of spring green-up (i.e. green-wave surfing). Nonetheless, empirical support for the Green Wave Hypothesis is mixed, and a framework for understanding variation in surfing is lacking. In a population of migratory mule deer (Odocoileus hemionus), 31% surfed plant phenology in spring as well as a theoretically perfect surfer, and 98% surfed better than random. Green-wave surfing varied among individuals and was unrelated to age or energetic state. Instead, the greenscape, which we define as the order, rate and duration of green-up along migratory routes,...
Populations of chemotactic bacteria are able to sense and respond to chemical gradients in their surroundings and direct their migration toward increasing concentrations of chemicals that they perceive to be beneficial to their survival. It has been suggested that this phenomenon may facilitate bioremediation processes by bringing bacteria into closer proximity to the chemical contaminants that they degrade. To determine the significance of chemotaxis in these processes it is necessary to quantify the magnitude of the response and compare it to other groundwater processes that affect the fate and transport of bacteria. We present a systematic approach toward quantifying the chemotactic response of bacteria in laboratory...
Oil spill response, whether planned by government agencies, oil spill cooperatives or individual companies, can be planned and carried out with the goal of minimizing ecological impacts, not merely removing visible oil. Two oil spill cooperatives on the west coast are implementing such planning. First, a coastal survey was conducted in the cooperative's area of responsibility. Physical processes and habitat types were examined. Oil spill cleanup guidelines were written for each habitat type. Biologically sensitive areas, those sites most vulnerable to oil spill impacts, were identified. Strategies were developed to protect most sensitive areas, i.e., prevent spilled oil from reaching them. Protection is the preferred...
Juvenile sculpin (Cottus extensus) less than 30 mm long exhibit a diel vertical migration in the limnetic zone of Bear Lake (Utah-Idaho). Using mid-water and bottom trawls we found that these fish inhabit the bottom of the lake (5� C) during the day but migrate 30?40 m into the water column at night where they reside in the metalimnion or epilimnion at temperatures near 13?16�C. Larger fish do not migrate into the water column. Stomach analyses demonstrated that the young-of-the-year fish do not migrate into the water column to feed: from July to October their diet is 70?93% benthic ostracods and copepods, and pelagic prey are rarely consumed. Furthermore, gut fullness of the sculpin increases through the daylight...
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In this observational pilot study, we worked at the largest existing solar tower facility in the world (Ivanpah Solar Electric Generating System - ISEGS) to assess the efficacy of using radar, surveillance video, and insect trapping to monitor animals flying near the towers. During week-long site visits in May and September, we monitored the airspace surrounding towers and observed insects, occasional birds, and bats under a variety of environmental and operational conditions. This dataset is comprised of the unedited digital thermal samples we gathered during those site visits and consist of 1280x720 pixel arrayed infrared measures from a FLIR SC8340HD science-grade thermal (SGT) camera with a 200mm lens. The data...
map background search result map search result map Invertebrate Data Radar Data Infrared (Thermal) Data Video Files Whooping Crane historic observation records, 1722-1941 Radio telemetry data on nighttime movements of two species of migratory nectar-feeding bats (Leptonycteris) in Hidalgo County, New Mexico, late-summer 2004 and 2005 Geospatial output data from the RVR Meander model of the Wabash River near the Interstate 64 Bridge near Grayville, Illinois Daily Surfing Invertebrate Data Radar Data Infrared (Thermal) Data Video Files Daily Surfing Radio telemetry data on nighttime movements of two species of migratory nectar-feeding bats (Leptonycteris) in Hidalgo County, New Mexico, late-summer 2004 and 2005 Whooping Crane historic observation records, 1722-1941