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At least 973 records · Page 54Linked to original sources
USGS2021

Rigorously valuing the coastal hazard risks reduction provided by potential coral reef restoration in Florida and Puerto Rico

The restoration of coastal habitats, particularly coral reefs, can reduce risks by decreasing the exposure of coastal communities to flooding hazards. In the United States, the protective services provided by coral reefs were recently assessed in social and economic terms, with the annual protection provided by U.S. coral reefs off the coasts of the State of Florida and the Commonwealth of Puerto Rico estimated to be more than 9,800 people and $859 million (2010 U.S. dollars). Hurricanes Irma and Maria in 2017 caused widespread damage to coral reefs in the State of Florida and the Commonwealth of Puerto Rico. Here we combine engineering, ecologic, geospatial, social, and economic data and tools to provide a rigorous valuation of where potential coral reef restoration could decrease the hazard faced by Florida and Puerto Rico’s reef-fronted coastal communities. The three restoration scenarios considered: (1) Ecological restoration, ‘E25’, which assumes planting 0.25-meter (m)-high corals on a (cross-shore) 25-m-wide reef; (2) Structural plus ecological, ‘S25’, which assumes emplacing a 1.00-m high structure with 0.25-m high corals on top on a 25 m wide reef; and (3) structural plus ecological, ‘S05’, which assumes emplacing a 1.00-m high structure with 0.25-m high corals on top on a 5 m wide reef. Planted corals are assumed to increase hydrodynamic roughness, thereby dissipating incident wave energy and decreasing flooding potential. We used a standardized approach to ‘place’ potential restoration projects throughout the whole (linear) extent of reefs bordering Florida and Puerto Rico to identify where coral reef restoration could be useful for meeting flood reduction benefits. We always sited potential restoration projects within the existing distribution of reefs even though many sites were far (kilometers [km]) offshore and some sites were relatively deep (up to 7 m depth). We followed risk-based valuation approaches to map flood zones at 10-square-meter resolution along all 980 km of Florida and Puerto’s Rico reef-lined shorelines for the three potential coral reef restoration scenarios and compare them to the flood zones without coral reef restoration. We quantified the potential coastal flood risk reduction provided by coral reef restoration using the latest information from the U.S. Census Bureau, Federal Emergency Management Agency, and Bureau of Economic Analysis for return-interval storm events. Using the damages associated with each storm probability, we also calculate the change in annual expected damages, a measure of the annual protection gained because of coral reef restoration. We found that the benefits of reef restoration off Florida and Puerto Rico are spatially highly variable. In most areas, we found little or no benefit from reef restoration (for example, restoration sites were far offshore or deep). However, there were a number of key areas where reef restoration could have substantial benefits for flood risk reduction. In particular, we estimated the protection gained by Florida and Puerto Rico’s coral reefs from coral reef restoration to result in: Avoided flooding to more than 5.6 square kilometers (2.16 square miles) of land annually; Avoided flooding affecting more than 3,100 people annually; Avoided direct damages of more than $124.2 million to more than 890 buildings annually; and Avoided indirect damages to more $148.7 million in economic activity owing to housing and business damage annually. Thus, the annual value of flood risk reduction provided by potential coral reef restoration in Florida and Puerto Rico is more than 3,100 people and $272.9 million (2010 U.S. dollars) in economic activity. These data provide stakeholders and decision makers with a spatially explicit, rigorous valuation of how, where, and when potential coral reef restoration in Florida and Puerto Rico can increase critical coastal storm flood reduction benefits. These results help identify areas where reef management, recovery, and restoration could potentially help reduce the risk to, and increase the resiliency of, Florida and Puerto Rico’s coastal communities.

Florida↗
USGS2004

Ground-water hydrology and water quality of the southern high plains aquifer, Melrose Air Force Range, Cannon Air Force Base, Curry and Roosevelt Counties, New Mexico, 2002-03

In cooperation with the U.S. Air Force, the U.S. Geological Survey characterized the ground-water hydrology and water quality at Melrose Air Force Range in east-central New Mexico. The purpose of the study was to provide baseline data to Cannon Air Force Base resource managers to make informed decisions concerning actions that may affect the ground-water system. Five periods of water-level measurements and four periods of water-quality sample collection were completed at Melrose Air Force Range during 2002 and 2003. The water-level measurements and water-quality samples were collected from a 29-well monitoring network that included wells in the Impact Area and leased lands of Melrose Air Force Range managed by Cannon Air Force Base personnel. The purpose of this report is to provide a broad overview of ground-water flow and ground-water quality in the Southern High Plains aquifer in the Ogallala Formation at Melrose Air Force Range. Results of the ground-water characterization of the Southern High Plains aquifer indicated a local flow system in the unconfined aquifer flowing northeastward from a topographic high, the Mesa (located in the southwestern part of the Range), toward a regional flow system in the unconfined aquifer that flows southeastward through the Portales Valley. Ground water was less than 55 years old across the Range; ground water was younger (less than 25 years) near the Mesa and ephemeral channels and older (25 years to 55 years) in the Portales Valley. Results of water-quality analysis indicated three areas of different water types: near the Mesa and ephemeral channels, in the Impact Area of the Range, and in the Portales Valley. Within the Southern High Plains aquifer, a sodium/chloride-dominated ground water was found in the center of the Impact Area of the Range with water-quality characteristics similar to ground water from the underlying Chinle Formation. This sodium/chloride-dominated ground water of the unconfined aquifer in the Impact Area indicates a likely connection with the deeper water-producing zone. No pesticides, explosives, volatile organic compounds, semivolatile organic compounds, organic halogens, or perchlorate were found in water samples from the Southern High Plains aquifer at the Range.

Scientific Investigations Report↗
USGS2018

The Central African Republic Diamond Database—A geodatabase of archival diamond occurrences and areas of recent artisanal and small-scale diamond mining

The alluvial diamond deposits of the Central African Republic (CAR) are mined almost exclusively by way of informal artisanal and small-scale mining (ASM) methods. ASM sites range in diameter from a few meters to 30 meters or more, and are typically excavated by crews of diggers using hand tools, sieves, and jigs. CAR’s reported annual production has ranged from 300,000 to 470,000 carats over the past decade. This production is significant for CAR because it accounts for a large portion of the country’s export income and employs an estimated 60,000 to 90,000 miners nationally. Diamond production has also been linked to the violent conflict and political instability which have plagued the country for decades. The most recent conflict began in 2012 and resulted in an international embargo on the export of rough diamonds from CAR. This embargo was followed by a ceasefire and a return of peace in certain zones of the country in 2015; however, political and economic instability continues to afflict many areas of the country. International efforts to restore peace in CAR have included United Nations support as well as international technical assistance in tracking, assessing, and monitoring diamond production. In 2015, the Kimberley Process (KP) developed an operational framework allowing for legitimate exports from five subprefectures in CAR that were deemed to be compliant with KP internal controls and which were also considered to be free from systematic violence or control of armed groups. The goal of this study was to address information gaps regarding the location and extent of diamond occurrences and mining activity through the integration of geologic research with remote sensing, geographic information systems analysis, and fieldwork. Effective and efficient monitoring of diamond mining activity using satellite imagery requires detailed understanding of the geographic distribution of diamond sources and mining activities. A two-phase methodology was developed to address the knowledge gaps. The first phase consisted of the creation of a comprehensive geospatial catalogue of diamond mining and occurrence locations from archival records such as historical maps, mining reports, academic publications, and field data. Building upon this locational database, the second phase consisted of the creation of a geospatial dataset cataloguing current mining activity locations through manual interpretation of recently acquired satellite imagery. The accuracy of this second geospatial dataset was then assessed using field observations made between 2016 and 2017 by the U.S. Agency for International Development’s Property Rights and Artisanal Diamond Development II project. This report presents a two-part geodatabase: part 1 contains the locations of diamond mine sites and occurrences from archival sources, and part 2 indicates areas of current or recent mining activity. This geodatabase is unique in its temporal and spatial extent and may be used to analyze the geographic distribution of CAR’s known diamond resources, to assess the effect of recent violent conflicts and KP actions on diamond produc-tion, to provide decision makers with information regarding small-scale diamond mining, and to improve the monitoring of mining in regions of the country prone to conflict.

Open-File Report↗
USGS2007

Understanding knowledge and perceptions of bats among residents of Fort Collins, Colorado

As regional urbanization increases in Colorado, so do interactions between humans and wildlife. Where previous habitat has been reduced due to urbanization and development, a few bat species that easily adapt to new environments now roost in homes and buildings (Kunz and Reynolds, 2003). Bats frequently serve as reservoirs of disease that have potential health consequences for humans and other mammals (Messenger and others, 2003). As bat use of buildings becomes more frequent, the incidences of bat/human contact and the risk of spreading disease also increase. In Colorado, rabies is most common in the big brown bat (Eptesicus fuscus) Pape and others, 1999), the most ubiquitous species of urban-dwelling bat in the United States (Barbour and Davis, 1969) and the most common species submitted for rabies testing in Colorado (Pape and others, 1999). An in-depth knowledge of the big brown bat - including its ecology, habitat and movements, and aspects of disease transmission - and of its interactions with humans is essential for making informed management decisions regarding this species. To balance the competing priorities of species preservation and public safety, natural resource managers and public health professionals must be able to accurately estimate citizens' knowledge, perceptions, and perceived risks regarding the bat species that use human dwellings and harbor diseases potentially dangerous to humans. A recently completed five-year ecological study (2001-2005) on bats inhabiting buildings in Fort Collins, Colo., has provided much information on the basic epidemiology of rabies and on the ecology of the local bat population (Davis, Rudd, and Bowen, 2007; Ellison and others, 2007; Neubaum, Douglas, and others, in press; Neubaum, O'Shea, and Wilson, 2006; Neubaum, Wilson, and O'Shea, 2007; O'Shea, Ellison, and Stanley, 2004; Pearce and O'Shea, 2007; Pearce and others, in press; Shankar and others, 2004; Shankar and others, 2005; Wimsatt and others 2005). Research investigating the human dimensions of bats and bat/rabies relationships, however, has been very limited (Gibbins and others, 2002; Liesener and others, 2006). Herein, we report the results of a study to evaluate perceptions and knowledge of bats and rabies among residents of Fort Collins, Colo. The study resulted from collaborations between U.S. Geological Survey (USGS) bat ecologists of the Trust Species and Habitats branch, and social scientists of the Policy Analysis and Science Assistance branch, both of the USGS Fort Collins Science Center (FORT).

Open-File Report↗
USGS2021

Improving species status assessments under the U.S. Endangered Species Act and implications for multispecies conservation challenges worldwide

Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline ESA decisions include multispecies recovery plans and habitat conservation plans. We address species status assessment (SSA), a USFWS process to inform ESA decisions from listing to recovery, within the context of multispecies and ecosystem planning. Although existing SSAs have a single-species focus, ecosystem-based research can efficiently inform multiple SSAs within a region and provide a foundation for transition to multispecies SSAs in the future. We considered at-risk grassland species and ecosystems within the southeastern United States, where a disproportionate number of rare and endemic species are associated with grasslands. To initiate our ecosystem-based approach, we used a combined literature-based and structured World Café workshop format to identify science needs for SSAs. Discussions concentrated on 5 categories of threats to grassland species and ecosystems, consistent with recommendations to make shared threats a focus of planning under the ESA: (1) habitat loss, fragmentation, and disruption of functional connectivity; (2) climate change; (3) altered disturbance regimes; (4) invasive species; and (5) localized impacts. For each threat, workshop participants identified science and information needs, including database availability, research priorities, and modeling and mapping needs. Grouping species by habitat and shared threats can make the SSA process and other planning processes for conservation of at-risk species worldwide more efficient and useful. We found a combination of literature review and structured discussion effective for identifying the scientific information and analysis needed to support the development of multiple SSAs.

Conservation Biology↗
USGS2025

Where to restore and conserve? A regional benefit cost analysis of coral reef protection and restoration for coastal flood resilience

Momentum is growing for the management of coral reefs as a strategy to reduce climate risks in tropical coastlines. Yet, quantification of the life-time costs, impacts, and benefits remains limited. This study provides one of the first rigorous, spatially explicit, regional-scale Benefit:Cost Analyses (BCA) for coral reef restoration and was designed to meet the BCA requirements of major hazard mitigation funding and programs. This study simulates coastal flooding using a hydrodynamic model under different scenarios representing current coral reef conditions, reef degradation, and reef restoration. These coastal flood maps are used to estimate socioeconomic damages, which are included in a BCA to assess cost-effectiveness and priority areas for coral reef conservation and restoration. The United States Virgin Islands is used as a case study given recent impacts from storms and their new policy that declares reefs as natural infrastructure. The results show that flood risk across the islands of Saint Croix, Saint John, and Saint Thomas is $51.4 million USD per year. Annually, coral reefs prevent flood damages to 481 people and $43.6 million USD of infrastructure, which represents 87 % of the flood risk. These results identify the communities that could receive the greatest benefits from coral conservation and restoration, which overlap significantly. Coral reef restoration is found to be a cost-effective strategy for flood mitigation although how reefs are restored matters. Hybrid coral reef restoration provides greater flood mitigation benefits than ecological restoration, but its cost-effectiveness is overall lower given its greater costs. Many coastal areas have benefit:cost ratios exceeding 1.5, which complies with typical government agencies’ requirements for accessing hazard mitigation funds. This valuation framework helps provide rigorous regional-scale quantification of nature-based coastal protection solutions for coastal risk management decisions.

Journal of Environmental Management↗
USGS1982

Habitat models for land-use planning: assumptions and strategies for development

Wildlife managers have long recognized that management goals must be constrained by the availability and suitability of habitat. This recognition, combined with ever increasing land development pressures, has resulted in environmental legislation emphasizing systematic approaches to collection and analysis of habitat information. Wildlife planners have responded with a variety of approached to the development of models that quantify habitat requirements. The use of habitat models in wildlife management is certainly not a new concept. Early models attempted to relate habitat quality and quantity as defined by various life requisites (Trippensee 1948). Conceptually, these early approaches are identical to many contemporary efforts directed at modeling habitat. This paper has two objectives related to contemporary habitat modeling approaches. The first objective is to characterize the assumptions and limitations inherent to operational habitat models. Various approaches to habitat modeling, some of which will be discussed at this conference, are described in their own terminology-which tends to obscure the fact that they have common ideals and are subject to the same sets of limitations. The second objective of this paper is to describe a strategy for development of habitat models consistent with these potential limitations. There seems to be two divergent perspectives on operational habitat models. The first is an ideal perspective, which views operational habitat models with skepticism because the current state of habitat knowledge is limited. The second is a pragmatic perspective, which recognizes that available habitat information, no matter how incomplete, can be used to improve the credibility of a land-use decision. The strategy outlined in this paper is directed toward the latter perspective but may help to bridge the gap between the pragmatic and ideal.

Book↗
USGS2007

Analysis of salinity intrusion in the Waccamaw River and Atlantic Intracoastal Waterway near Myrtle Beach, South Carolina, 1995-2002

Six reservoirs in North Carolina discharge into the Pee Dee River, which flows 160 miles through South Carolina to the coastal communities near Myrtle Beach, South Carolina. During the Southeast's record-breaking drought from 1998 to 2003, salinity intrusions inundated a coastal municipal freshwater intake, limiting water supplies. To evaluate the effects of regulated flows of the Pee Dee River on salinity intrusion in the Waccamaw River and Atlantic Intracoastal Waterway, the South Carolina Department of Natural Resources and a consortium of stakeholders entered into a cooperative agreement with the U.S. Geological Survey to apply data-mining techniques to the long-term time series to analyze and simulate salinity dynamics near the freshwater intakes along the Grand Strand of South Carolina. Salinity intrusion in tidal rivers results from the interaction of three principal forces—streamflow, mean tidal water levels, and tidal range. To analyze, model, and simulate hydrodynamic behaviors at critical coastal gages, data-mining techniques were applied to over 20 years of hourly streamflow, coastal water-quality, and water-level data. Artificial neural network models were trained to learn the variable interactions that cause salinity intrusions. Streamflow data from the 18,300-square-mile basin were input to the model as time-delayed variables and accumulated tributary inflows. Tidal inputs to the models were obtained by decomposing tidal water-level data into a "periodic" signal of tidal range and a "chaotic" signal of mean water levels. The artificial neural network models were able to convincingly reproduce historical behaviors and generate alternative scenarios of interest. To make the models directly available to all stakeholders along the Pee Dee and Waccamaw Rivers and Atlantic Intracoastal Waterway, an easy-to-use decision support system (DSS) was developed as a spreadsheet application that integrates the historical database, artificial neural network models, model controls, streaming graphics, and model output. An additional feature is a built-in optimizer that dynamically calculates the amount of flow needed to suppress salinity intrusions as tidal ranges and water levels vary over days and months. This DSS greatly reduced the number of long-term simulations needed for stakeholders to determine the minimum flow required to adequately protect the freshwater intakes.

South Carolina↗
USGS2021

A framework for allocating conservation resources among multiple threats and actions

Land managers decide how to allocate resources among multiple threats that can be addressed through multiple possible actions. Additionally, these actions vary in feasibility, effectiveness, and cost. We sought to provide a way to optimize resource allocation to address multiple threats when multiple management options are available, including mutually exclusive options. Formulating the decision as a combinatorial optimization problem, our framework takes as inputs the expected impact and cost of each threat for each action (including do nothing) and for each overall budget identifies the optimal action to take for each threat. We compared the optimal solution to an easy to calculate greedy algorithm approximation and a variety of plausible ranking schemes. We applied the framework to management of multiple introduced plant species in Australian alpine areas. We developed a model of invasion to predict the expected impact in 50 years for each species‐action combination that accounted for each species’ current invasion state (absent, localized, widespread); arrival probability; spread rate; impact, if present, of each species; and management effectiveness of each species‐action combination. We found that the recommended action for a threat changed with budget; there was no single optimal management action for each species; and considering more than one candidate action can substantially increase the management plan's overall efficiency. The approximate solution (solution ranked by marginal cost‐effectiveness) performed well when the budget matched the cost of the prioritized actions, indicating that this approach would be effective if the budget was set as part of the prioritization process. The ranking schemes varied in performance, and achieving a close to optimal solution was not guaranteed. Global sensitivity analysis revealed a threat's expected impact and, to a lesser extent, management effectiveness were the most influential parameters, emphasizing the need to focus research and monitoring efforts on their quantification.

Conservation Biology↗
USGS1983

Ground-water contamination at Wurtsmith Air Force Base, Michigan

A sand and gravel aquifer of glacial origin underlies Wurtsmith Air Force Base in northeastern lower Michigan. The aquifer overlies a thick clay layer at an average depth of 65 feet. The water table is about 10 feet below land surface in the western part of the Base and about 25 feet below land surface in the eastern part. A ground-water divide cuts diagonally across the Base from northwest to southeast. South of the divide, ground water flows to the Au Sable River; north of the divide, it flows to Van Etten Creek and Van Etten Lake. Mathematical models were used to aid in calculating rates of groundwater flow. Rates range from about 0.8 feet per day in the eastern part of the Base to about 0.3 feet per day in the western part. Models also were used as an aid in making decisions regarding purging of contaminated water from the aquifer. In 1977, trichloroethylene was detected in the Air Force Base water-supply system. It had leaked from a buried storage tank near Building 43 in the southeastern part of the Base and moved northeastward under the influence of the natural ground-water gradient and the pumping of Base water-supply wells. In the most highly contaminated part of the plume, concentrations are greater than 1,000 micrograms per liter. Current purge pumping is removing some of the trichloroethylene, and seems to have arrested its eastward movement. Pumping of additional purge wells could increase the rate of removal. Trichloroethylene has also been detected in ground water in the vicinity of the Base alert apron, where a plume from an unknown source extends northeastward off Base. A smaller, less well-defined area of contamination also occurs just north of the larger plume. Trichloroethylene, identified near the waste-treatment plant, seepage lagoons, and the northern landfill area, is related to activities and operations in these areas. Dichloroethylene and trichloroethylene occur in significant quantities westward of Building 43, upgradient from the major spill site. Benzene, indicative of ground-water contamination by a fuel substance, occurs in an area northeast of the bulk-fuel storage area. Analysis of a variety of chemical, physical, and biologic characteristics of water on the Base indicate that there is a measurable affect on ground-water quality from landfills, the seepage lagoon, and the waste-treatment plant.

Michigan↗
USGS2004

The effects of urbanization on the biological, physical, and chemical characteristics of coastal New England streams

During August 2000, responses of biological communities (invertebrates, fish, and algae), physical habitat, and water chemistry to urban intensity were compared among 30 streams within 80 miles of Boston, Massachusetts. Sites chosen for sampling represented a gradient of the intensity of urban development (urban intensity) among drainage basins that had minimal natural variability. In this study, spatial differences were used as surrogates for temporal changes to represent the effects of urbanization over time. The degree of urban intensity for each drainage basin was characterized with a standardized urban index (0-100, lowest to highest) derived from land cover, infrastructure, and socioeconomic variables. Multivariate and multimetric analyses were used to compare urban index values with biological, physical, and chemical data to determine how the data indicated responses to urbanization. Multivariate ordinations were derived for the invertebrate-, fish-, and algae-community data by use of correspondence analysis, and ordinations were derived for the chemical and physical data by use of principal-component analysis. Site scores from each of the ordinations were plotted in relation to the urban index to test for a response. In all cases, the primary axis scores showed the strongest response to the urban index, indicating that urbanization was a primary factor affecting the data ordination. For the multimetric analyses, each of the biological data sets was used to calculate a series of community metrics. For the sets of chemical and physical data, the individual variables and various combinations of individual variables were used as measured and derived metrics, respectively. Metrics that were generally most responsive to the urban index for each data set included: EPT (Ephemeroptera, Plecoptera, Trichoptera) taxa for invertebrates; cyprinid taxa for fish; diatom taxa for algae; bicarbonate, conductivity, and nitrogen for chemistry; and water depth and temperature for physical habitat. The slopes of the responses generally were higher between the urban index values of 0 to 35, indicating that the greatest change in aquatic health may occur between low and moderate levels of urban intensity. Additionally, many of the responses showed that at urban index values greater than 35, there was a threshold effect where the response variable no longer changed with respect to urban intensity. Recognizing and understanding this type of response is important in management and monitoring programs that rely on decisive interpretations of variable responses. Any biological, physical, or chemical variable that is used to characterize stream health over a gradient of disturbance would not be a reliable indicator when a level of disturbance is reached where the variable does not respond in a predictable manner.

Maine, Massachusetts, New Hampshire↗
USGS2021

Using high resolution satellite and telemetry data to track flooded habitats, their use by waterfowl, and evaluate effects of drought on waterfowl and shorebird bioenergetics in California

Wetland managers in the Central Valley of California, a dynamic hydrological landscape, require information regarding the amount and location of existing wetland habitat to make decisions on how to best use water resources to support multiple wildlife objectives, particularly during drought. Scientists from the U.S. Geological Survey Western Ecological Research Center (WERC), Point Blue Conservation Science (Point Blue), and the U.S. Fish and Wildlife Service (USFWS) partnered to learn how wetland and flooded agricultural habitats used by waterfowl and shorebirds change during the non-breeding season (July–April) particularly during drought. During extreme drought conditions, the ability to provide sufficient water for wildlife often depends on the timing of water deliveries to managed wetlands and winter-flooded crop fields and decisions on whether to fallow croplands. Waterfowl and shorebirds could be particularly affected by these decisions because they typically rest and feed in flooded habitats. Poor habitat conditions resulting from spatially or temporally suboptimal water deliveries (that is, mismatch between waterfowl habitat needs and timing and location of flooded habitats) could reduce waterfowl hunting opportunities and body condition. Point Blue scientists developed a system for near real-time tracking of habitats used by waterfowl, shorebirds, and some other wetland-dependent “waterbirds” ( www.pointblue.org/watertracker ) and to assess the impacts of drought on habitat availability and on waterfowl and shorebird bioenergetics. The WERC researchers linked these data with near real-time tracking (telemetry) data of duck locations throughout the Valley. The team used these two datasets to relate duck locations to open-water characteristics and to learn how waterfowl use habitats under spatially and temporally changing conditions during drought and non-drought periods. We found that recent extreme drought (2013–15) significantly changed the timing and magnitude of flooding and consequently reduced the availability of habitats used by waterfowl and shorebirds more than other recent historic droughts 2000–11. Drought reduced irrigations of moist soil seed plants and thus there was lower food energy available for waterfowl. Analyses using bioenergetics models indicated that, overall, extreme drought increased food energy deficits (total number of deficit days) for shorebirds and waterfowl. Our analysis indicated a strong direct relationship between duck locations and classified habitat derived from open-water data during the wintering period (October–March). This result helps confirm the application of dynamic water data to identify flooded areas that provide waterfowl habitat. Presence of open water at a 1-hectare resolution can be used effectively to identify flooded landscape areas available as habitat for ducks. Our discoveries from evaluating use of space by ducks also indicated that nighttime feeding locations of ducks were concentrated nearby primary roosts and that foraging distances could depend on hydrologic dynamics of location (Suisun Marsh versus California excluding Suisun Marsh) and time of season (early, middle, late). Other results indicated that some areas on the California landscape with extremely reliable water supplies could receive consistent use by ducks year after year (in essence, almost drought proof). The Water Tracker is set up to automatically track wetland habitat and food availability each year and is making these data available to water and wetland managers. Results from this research are a significant step toward understanding how waterfowl and shorebird habitats can be optimally managed on the landscape to support desired populations of these migratory birds during extreme drought.

California↗
USGS2022

Estimating stream temperature in the Willamette River Basin, northwestern Oregon—A regression-based approach

The alteration of thermal regimes, including increased temperatures and shifts in seasonality, is a key challenge to the health and survival of federally protected cold-water salmonids in streams of the Willamette River basin in northwestern Oregon. To better support threatened fish species, the U.S. Army Corps of Engineers (USACE) and other water managers seek to improve the thermal regime in the Willamette River and key tributaries downstream of USACE dams by utilizing strategically timed flow releases from USACE dams. To inform flow management decisions, regression relations were developed for 12 Willamette River basin locations below USACE dams relating stream temperature with streamflow and air temperature utilizing publicly available datasets spanning 2000–18. The resulting relations provide simple tools to investigate stream temperature responses to changes in streamflow and climatic conditions in the Willamette River system. Regression relations on the Willamette River and key tributaries show that, at locations sufficiently distant from the direct temperature influence of upstream dam releases, air temperature and streamflow are reasonable proxies to predict the 7-day average of the daily mean (7dADMean) and 7-day average of the daily maximum (7dADMax) water temperature with errors generally ≤1 degrees Celsius (°C). To account for seasonal variations in the relation between air temperature, streamflow, and stream temperature, a transition-smoothed, seasonal regression approach was used. Stream temperature is inversely correlated with streamflow in all seasons except “winter” (January–March), when it is relatively independent. Stream temperature is positively correlated with air temperature in all seasons, but the slope decreases at very low or very high air temperatures. Generally, fit is best for seasonal models “winter” (January–March), “spring” (April–May), “summer” (June–August), and “early autumn” (September–October). Error in “autumn” (November–December) is larger, probably due to variation in the onset timing of winter storms. Simulated results from a climatological analysis of predicted stream temperature suggest that, excluding extremes and accounting for some seasonal variability, the 7dADMean and 7dADMax stream temperature sensitivity to air temperature and streamflow varies by location on the river. To investigate the potential range of stream temperature variability based on historical air temperature and streamflow conditions, stream temperature predictions were calculated using synthetic time series comprised of daily temperature values representing the 0.10, 0.33, 0.50, 0.67, and 0.90 quantile of air temperature and streamflow from 1954 (the year meaningful streamflow augmentation began) to 2018. Results show that from a “very hot” (0.90 quantile) and “very dry” (0.10 quantile) year to a “very cool” (0.10 quantile) and “very wet” (0.90; all quantiles from 1954 to 2018) year, the stream temperature sensitivity to air temperature and streamflow is about 3 °C at Harrisburg (river mile 161.0) and increases to about 5 °C at Keizer (river mile 82.2). While the number of days exceeding regulatory criteria are fewer in cooler, wetter years than in warmer, dryer years, the models suggest that the Willamette River will likely continue to exceed the State of Oregon maximum water-temperature criterion of 18 °C for sustained periods from late spring to early autumn and that the flow management practices evaluated in this study, while effective at influencing stream temperature, likely cannot prevent many or all such exceedances. As modeled for 2018, a representative very hot year with normal to below-normal streamflow, stream temperature sensitivity to changes in streamflow of ±100 to ±1000 cubic feet per second produced mean monthly temperature changes from 0.0 to 1.4 °C at Keizer, Albany, and Harrisburg during summer. For a specified change in flow, temperature sensitivity is greater at upstream locations where streamflow is less than that at downstream locations because the change in streamflow is a greater percentage of total streamflow at upstream locations. Similarly, temperature response to a set change in flow is greater in the summer and early autumn low-flow season than in spring when flows are higher. The regression models developed in this study thus indicate that flow management is likely to have a greater effect on stream temperature at upstream locations (such as Harrisburg or Albany) and during the low-flow season than at downstream locations (such as Keizer) or during periods of higher streamflow.

Oregon↗
USGS2016

Using a full annual cycle model to evaluate long-term population viability of the conservation-reliant Kirtland's warbler after successful recovery

Long-term management planning for conservation-reliant migratory songbirds is particularly challenging because habitat quality in different stages and geographic locations of the annual cycle can have direct and carry-over effects that influence the population dynamics. The Neotropical migratory songbird Kirtland's warbler Setophaga kirtlandii (Baird 1852) is listed as endangered under the U.S. Endangered Species Act and Near Threatened under the IUCN Red List. This conservation-reliant species is being considered for U.S. federal delisting because the species has surpassed the designated 1000 breeding pairs recovery threshold since 2001. To help inform the delisting decision and long-term management efforts, we developed a population simulation model for the Kirtland's warbler that incorporated both breeding and wintering grounds habitat dynamics, and projected population viability based on current environmental conditions and potential future management scenarios. Future management scenarios included the continuation of current management conditions, reduced productivity and carrying capacity due to the changes in habitat suitability from the creation of experimental jack pine Pinus banksiana (Lamb.) plantations, and reduced productivity from alteration of the brown-headed cowbird Molothrus ater (Boddaert 1783) removal programme. Linking wintering grounds precipitation to productivity improved the accuracy of the model for replicating past observed population dynamics. Our future simulations indicate that the Kirtland's warbler population is stable under two potential future management scenarios: (i) continuation of current management practices and (ii) spatially restricting cowbird removal to the core breeding area, assuming that cowbirds reduce productivity in the remaining patches by ≤41%. The additional future management scenarios we assessed resulted in population declines. Synthesis and applications . Our study indicates that the Kirtland's warbler population is stable under current management conditions and that the jack pine plantation and cowbird removal programmes continue to be necessary for the long-term persistence of the species. This study represents one of the first attempts to incorporate full annual cycle dynamics into a population viability analysis for a migratory bird, and our results indicate that incorporating wintering grounds dynamics improved the model performance.

Michigan↗
USGS2014

Unmanned aircraft systems (UAS) activities at the Department of the Interior

The U.S. Department of the Interior (DOI) is responsible for protecting and managing the natural resources and heritage on almost 20% of the land in the United States. The DOI’s mission requires access to remotely sensed data over vast lands, including areas that are remote and potentially dangerous to access. Unmanned Aircraft Systems (UAS) technology has the potential to enable the DOI to be a better steward of the land by: (1) Improving natural hazard forecasting and the analysis of the impacts. (2) Improving the understanding of climate change to better plan for likely impacts. (3) Developing precipitation and evaporation forecasting to better manage water resources. (4) Monitoring Arctic ice change and its impacts on ecosystems, coasts, and transportation. (5) Increasing safety and effectiveness of wildland fire management. (6) Enhancing search and rescue capabilities. (7) Broadening the abilities to monitor environmental or landscape conditions and changes. (8) Better understanding and protecting the Nation’s ecosystems. The initial operational testing and evaluations performed by the DOI have proven that UAS technology can be used to support many of the Department’s activities. UAS technology provides scientists a way to look longer, closer and more frequently at some of Earth’s most remote areas—places that were previously too dangerous or expensive to monitor in detail. The flexibility of operations and relative low cost to purchase and operate Small Unmanned Aerial System (sUAS) enhances the ability to track long-term landscape and environmental change. The initial testing indicates the operational costs are approximately 10% of traditional manned aircraft. In addition, users can quickly assess landscape-altering events such as wildland fires, floods and volcanoes. UAS technology will allow the DOI to do more with less and in the process enhance the Department’s ability to provide unbiased scientific information to help stakeholders make informed decisions. It will also provide a digital baseline record that can be archived and used when monitoring future events or conditions. One possible future scenario has scientists carrying sUAS into the field allowing quick deployment and operation to observe the environment or for emergency response. This scenario could also include a persistent monitoring capability provided by a UAS that can stay airborne over a small geographic area for days or weeks, or possibly longer. While the DOI focus is on sUAS, the Department recognizes that larger UAS systems will also play a role in meeting its mission. The Department anticipates meeting long-duration or specialized acquisition commitments, such as state or national aerial photography, by collaboration with other agencies or through commercial contracts. Even though the DOI continues to evaluate UAS and sensor technology to meet the Department’s mission, some of its bureaus are already moving towards an operational capability. The authors fully anticipate that by 2020 UAS will emerge as one of the primary platforms for DOI remote sensing applications.

Photogrammetric Engineering and Remote Sensing↗
USGS2010

Postfledging survival of Laysan ducks

Precise and unbiased estimates of demographic parameters are necessary for effective population monitoring and to parameterize population models (e.g., population viability analyses). This is especially important for endangered species, where recovery planning and managers' decisions can influence species persistence. In this study, we used mark–recapture methods to estimate survival of fledged juveniles (hatch-yr [HY]) and adult (after-hatch-yr [AHY]) Laysan ducks ( Anas laysanensis ), an endangered anatid restricted to Laysan Island in the northwestern Hawaiian Islands. To better understand population dynamics, we examined how survival varied as a function of Laysan duck density during 1998–2004. Using random effects models, we also quantified process variation in survival, thereby quantifying the appropriate source of variation for future population models. The dataset supported variation in survival that was time (yr), age (AHY vs. HY), and sex specific. Due to small sample sizes, we did not examine time specificity in the survival of HY ducks. Survival of HY ducks was 0.832 (SE = 0.087) for females ( n = 21) and 0.999 (SE < 0.001) for males ( n = 15) during 1998–2001. Trends in time and density lacked support as sources of variation in the survival of AHY ducks during 1998–2004. After-hatch-year survival ranged from 0.792 (SE = 0.033) to 0.999 (SE < 0.001). Where we modeled survival as a random effect, annual survival for AHY females was 0.881 (SE = 0.017) and process variation (σ S ) was 0.034. For AHY males, annual survival (μ S ) was 0.906 (SE = 0.019) and process variation (σ S ) was 0.040. This information will improve existing population viability analysis models for Laysan ducks. We believe that monitoring the source and translocation populations will be paramount for increasing our understanding of Laysan duck dynamics, recovery planning, and population management.

Journal of Wildlife Management↗
USGS2019

Monitoring breeding and survival of ring-necked pheasant (Phasianus colchicus) in the Sacramento Valley, Sacramento-San Joaquin River Delta, and Klamath Basin, northern California—Five-year summary, 2013–17

The U.S. Geological Survey Western Ecological Research Center, Pheasants Forever, Mandeville Island Duck Club, and the California Department of Fish and Wildlife collaborated in a reconnaissance study to monitor populations of ring-necked pheasant ( Phasianus colchicus ) using radio-telemetry in the Sacramento Valley, Sacramento-San Joaquin River Delta, and Klamath Basin of northern California. The purpose of this study was to provide agencies and private landowners with a framework of decision-support tools to help manage pheasant populations in California. During winter, spring, and autumn of 2013–17, we radio- or Global Positioning System-marked 227 female pheasant across six study sites. Data collection was focused on investigating nest-site and brood-rearing habitat selection, examining avian predator composition, and estimating population vital rates to improve our understanding of pheasant population dynamics and to identify factors that may contribute to decreases in pheasant populations in California. The cumulative annual adult survival probability across all sites during 2013–17 was 27.6 percent (95-percent confidence interval [CI], 21.9–33.6), and the cumulative nest and brood survival probabilities were 34.5 percent (95-percent CI, 27.0–42.2) and 54.2 percent (95-percent CI, 43.7–63.5), respectively. Evidence from microhabitat surveys completed at nest-sites, brood locations, and random locations suggested that marked female pheasant tended to select increasing vertical cover and residual vegetation cover and tended to avoid areas of increasing bare ground cover regardless of life-history stage. However, females at nest-sites selected increasing grass cover and height, whereas brood-rearing females tended to select increasing forb cover and height. Only perennial grass cover and perennial grass height were shown to have a positive influence on nest survival, which suggests that increasing perennial grass cover in areas occupied by pheasant may increase nest survival. Analysis of environmental factors linked to vital rate information are ongoing and will continue with investigations at increased spatial scales (that is, macro-habitat) to develop integrated population models that can incorporate abundance estimates from crow count data with vital rates from telemetry data. This report includes results from 5 years of data collection and should be interpreted with caution, as these findings are preliminary.

California↗
USGS2021

Assessment of diel cycling in nutrients and trace elements in the Eagle River Basin, 2017–18

Diel cycles are known to occur in all types of waters, and increasing studies indicate routine water samples may not provide an accurate snapshot in concentrations of trace elements and nutrients. Diel behavior in neutral to alkaline pH ranges is independent of streamflow variability and concentration. Extensive historical U.S. Geological Survey (USGS) water-quality data have been collected in the Eagle River Basin during daylight hours, which is defined as the period of time between one-half hour prior to sunrise and one-half hour after sunset. However, no USGS data have been collected throughout the nighttime, defined as the time between one-half hour after sunset and one-half hour prior to sunrise, making the evaluation of diel cycles impossible. To assess the importance of diel cycling within the Eagle River Basin, the USGS, in cooperation with Eagle River Watershed Council, developed a study to assess the mechanisms, patterns, and magnitude of change during the diel cycle for selected constituents. Water-quality monitors at five USGS streamgage sites (09065500, Gore Creek at Upper Station, near Minturn, Colorado, 09063000, Eagle River at Red Cliff, Colorado, 09064600, Eagle River near Minturn, Colorado, 09066325, Gore Creek above Red Sandstone Creek at Vail, Colorado, and 394220106431500, Eagle River below Milk Creek near Wolcott, Colorado) were deployed in 2017 to evaluate the water-quality field parameters and to determine if water conditions were favorable for the diel cycling of nutrients and trace elements. Based on the evaluation of water-quality parameters, three of the five sites were sampled for nutrient and trace-element concentrations in 2018 to confirm the presence and magnitude of diel cycling. Historical data were also analyzed to assess the effect of time of day on measured nutrient and trace-element concentrations. An assessment of the effect of land use on diel cycling was also investigated. Measurable nutrients displayed a diel cycle at all three sites with the largest percentage change at the most downstream site (394220106431500), located on the Eagle River. More notable diel cycles at this site include filtered nitrate plus nitrite, which varied 179 percent, with concentrations from 0.24 to 0.67 milligrams per liter (mg/L) and filtered orthophosphate, which varied 71 percent, with concentrations from 0.07 to 0.12 mg/L. Filtered nitrate plus nitrite at site 09066325 varied 57 percent, ranging from 0.14 to 0.22 mg/L. Maximum concentrations occurred prior to noon, decreased through the afternoon (between noon and sunset), and increased during the night (between sunset and sunrise). That pattern is consistent with nutrient uptake in response to daytime (between sunrise and sunset) photosynthesis along with biologically driven denitrification and nitrification cycles. Nutrient concentrations at sites 09064600 and 09066325 were generally low and below laboratory reporting limits, which is the smallest measured concentration that nutrients could be measured by a given analytical method. Trace-element concentrations were detectable at all sites with the largest percentage change at the most downstream site (394220106431500) and exhibited diel concentration variation from 11.6 to 284 percent. Appreciable diel cycles included filtered copper (0.98–1.40 micrograms per liter [µg/L], 42.9 percent), filtered zinc (less than [<] 4.00–5.50 µg/L, greater than [>] 37.5 percent), total manganese (9.70–19.5 µg/L, 101 percent), and total arsenic (0.30–0.40 µg/L, 33.3 percent). The largest percentage change in concentration was filtered manganese (2.84–10.9 µg/L, 284 percent). Diel cycles at site 09064600 ranged from 9.1 to 64.5 percent across the trace elements measured. Dissolved trace elements with appreciable diel cycles during the sampling period include filtered cadmium (0.09–0.12 µg/L, 33.3 percent), filtered copper (0.99–1.40 µg/L, 41.4 percent), and total arsenic (0.20–0.30 µg/L, 50 percent). The largest percentage change was filtered zinc (38.3–63.0 µg/L, 65 percent). Trace-element concentrations at site 09066325 were below laboratory reporting limits for many parameters, and no diel cycle could be assessed for these parameters. However, total recoverable iron, filtered barium, filtered manganese, and filtered selenium exhibited changes in concentrations of <10.0–19.4 µg/L (>94 percent), 115–121 µg/L (5 percent), 1.44–1.72 µg/L (19.4 percent), and 0.25–0.28 µg/L (12 percent), respectively. At sites 09064600 and 394220106431500, maximum trace-element concentrations occurred during nighttime with some variation regarding the timing of the peak. The exceptions to this were filtered copper, total arsenic, and filtered selenium, which had maximum concentrations around noon or as the sun disappeared below the horizon. The timing of minimum concentrations occurred in the afternoon for many trace elements, with filtered copper, total arsenic, and filtered selenium having minimum concentrations in the morning or just prior to the appearance of the sun. Analysis of historical data also showed evidence of diel cycling. Historical samples collected from July through October were used to identify diel cycling in base-flow conditions. The resulting diel pattern in the median concentration for filtered manganese, filtered zinc at water-quality site 09064600, and filtered manganese and filtered nitrate plus nitrite at water-quality site 39422016431500 were consistent with the diel pattern in the September 2018 samples, and indicate time of day can bias sampling results even during daylight hours. Diel cycling in the Eagle River Basin appears to be driven primarily by instream, biological processes. However, land use, particularly human effects downstream from urban areas, mining, and agriculture, may affect these processes. At some locations, diel variations in nutrient and trace-element concentrations are small enough to be of low concern. At other locations, however, variations in concentrations up to 284 percent in the data collected for this study and 214 percent in base-flow historical data, indicate daytime-only sampling, particularly in late afternoon, can underestimate daily average nutrient and trace-element concentrations. When feasible, the potential of diel cycling warrants consideration in sample design to account for the potential of diel cycles, or at a minimum, be recognized as a component of the river dynamic and the potential consequences that diel cycles may have in data interpretation and river management decisions.

Colorado↗