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At least 487 records · Page 27Linked to original sources
USGS2022

Effects of prescribed fire on prenesting movements of wild turkeys in Arkansas

The restoration of historic disturbance regimes is an increasingly common management strategy to conserve disturbance-dependent communities and species, and enhance resilience of ecosystems to climate change or plant and animal invasions. However, the reintroduction of frequent and wide-scale disturbance may have unexpected consequences on species that are accustomed to an environment absent of frequent disturbance. Implementation of frequent prescribed fire for community restoration has coincided with population declines of eastern wild turkeys ( Meleagris gallopavo silvestris ) in the Ozark Highlands of Arkansas. We investigated whether there was evidence of linkage between wild turkey movement behavior and habitat use and the widespread use of prescribed fire that began in 2002 and continued through the end of our study in 2013. We fitted 67 female wild turkeys with satellite transmitters in 2012 and 2013 on the White Rock Ecosystem Restoration Area to estimate annual and seasonal home ranges and examine pre-nesting habitat use at multiple spatial scales. Home range was larger for adults in 2013 (4,750 ha, SE = 946.2, n = 12) than in 2012 (2,703 ha, SE = 283.4, n = 19). Mean pre-nesting ranges for adults were 1,633 ha (SE = 238.9, n = 23) in 2012 and 1,118 ha (SE = 158.8, n = 18) in 2013, smaller than those of sub-adults, 1,761 ha (SE = 581.2, n = 3) in 2012 and 5,576 ha (SE = 2260, n = 8) in 2013. Habitat selection analyses for the pre-nesting period indicated that wild turkeys used locations with more variability in canopy cover and vegetation height and in smaller patch sizes than expected based on availability. However, female wild turkeys selected nesting cover that had more variability in canopy cover and vegetation height but in larger patches. Differences in sub-adults and adult home and seasonal ranges suggest that other factors such as density dependence or social hierarchy could be driving movements as opposed to prescribed fire application. Wild turkey females selected variable vegetation structure during the pre-nesting and nesting periods with characteristics that could be a result of frequent prescribed fire or forest succession. However, we documented no direct evidence these characteristics or other aspects of the prescribed fire program were causing wild turkey population declines.

Arkansas↗
USGS2013

Fluvial rainbow trout contribute to the colonization of steelhead ( Oncorhynchus mykiss ) in a small stream

Life history polymorphisms provide ecological and genetic diversity important to the long term persistence of species responding to stochastic environments. Oncorhynchus mykiss have complex and overlapping life history strategies that are also sympatric with hatchery populations. Passive integrated transponder (PIT) tags and parentage analysis were used to identify the life history, origin (hatchery or wild) and reproductive success of migratory rainbow/steelhead for two brood years after barriers were removed from a small stream. The fluvial rainbow trout provided a source of wild genotypes to the colonizing population boosting the number of successful spawners. Significantly more parr offspring were produced by anadromous parents than expected in brood year 2005, whereas significantly more parr offspring were produced by fluvial parents than expected in brood year 2006. Although hatchery steelhead were prevalent in the Methow Basin, they produced only 2 parr and no returning adults in Beaver Creek. On average, individual wild steelhead produced more parr offspring than the fluvial or hatchery groups. Yet, the offspring that returned as adult steelhead were from parents that produced few parr offspring, indicating that high production of parr offspring may not be related to greater returns of adult offspring. These data in combination with other studies of sympatric life histories of O. mykiss indicate that fluvial rainbow trout are important to the conservation and recovery of steelhead and should be included in the management and recovery efforts.

Washington↗
USGS2024

Enhanced microplastic fragmentation along human built structures in an urban waterway

Plastic pollution and microplastic (MP, 1 µm to 5 mm) generation are growing problems affecting the global community and a wide range of natural and disturbed environments. Urban and suburban waterways are directly impacted by plastic pollution due to their proximity to population centers and many different types single use plastic waste sources. In this study, plastic waste accumulation and fragmentation was investigated along the Cooper River in Camden County, NJ. Polymer composition was identified for individual plastic waste particles collected along the Cooper River using Fourier transform infrared (FTIR) spectrometry. Multiple human-built structures (Wallworth Lake, Evans Pond and Hopkins Pond dams) along the Cooper River were found to accumulate different types of plastic waste. The accumulation of plastic waste along these structures resulted in the initial stages of plastic fragmentation and the identification of large MP particles (1 to 5 mm). Quantitative analysis revealed that fragmented polystyrene (PS) particles constituted 82.8% of the total plastic fragments identified, most of which were identified at the Wallworth Lake dam. Many other types of fragmented plastic litter, including polyethylene and polypropylene, were identified at the Wallworth Lake dam, as well. This research demonstrates that engineered structures within urban and suburban aquatic ecosystems serve as significant aggregators of plastic debris, thereby catalyzing its breakdown into microplastics. Considering the escalating ecological and human health ramifications of microplastic proliferation, the fragmentation of plastic waste in an urban and suburban waterway observed in this study can also result in potentially toxic smaller MP particles, and increased exposure to aquatic organisms and humans.

New Jersey↗
USGS2004

Chapter 4 The meade peak member of the phosphoria formation: Temporal and spatial variations in sediment geochemistry

Variations in the geochemistry of rocks from the Meade Peak Member of the Phosphoria Formation were examined using ratios of elements associated with either the +terrigenous or marine sediment fractions. Inter-element relationships in the terrigenous fraction appear useful for chemo-stratigraphic correlation. A sharp decrease upsection in K 2 O/AI 2 O 3 ratios occurs in the lower half of all but the most northeasterly section, wherein an offset is still evident in average and minimum values. These offsets correspond closely to the lower Guadalupian Series boundary as defined by conodont zonations, coincident with a change from major low-stand to transgressive conditions. The offsets are possibly the result of increased transport distances or flooding of source areas related to transgres- sion of the Phosphoria sea on the Wyoming shelf. A series of intervals displaying high Fe 2 O 3 /Al 2 O 3 , Ba/Al 2 O 3 and Sc/Al 2 O 3 ratios occur in the upper beds of the easternmost sections. The intervals do not appear to reflect amplified marine signals, but rather the introduction of terrigenous sediment from a secondary source, or, simply, reworking of sediments under higher energy conditions. The westernmost section, presumably repre- senting the deepest parts of the Phosphoria basin, contains intervals with high Ba/Al 2 O 3 . We suggest these horizons represent periods of low sediment accumulation during maxi- mum flooding and high-stand conditions. Inter-element relationships in the marine-derived sediment fraction indicate that bottom waters of the Phosphoria basin were dominantly denitrifying (suboxic). Ratios of Cd and Mo to Zn and Cu closely approach those in modern plankton in most of the sections, implying a major biogenic source for these elements. Exceptions occur through- out the westernmost (distal) section, possibly due to changes in the dominant plankton populations and relative nutrient uptakes, and in the upper part of the most northeasterly (shoreward, ramp) section, which we suggest is due to increased oxygen levels. Relatively thick phosphatic layers occur in basinal areas due largely to lack of terrig- enous dilution during deposition. These basinal deposits appear to have lower concentra- tions of many trace elements than more shoreward deposits. This may reflect deposition away from areas of peak primary production. Alternatively, biogenic detritus in these areas may have been derived from differing populations of primary producers with differing nutrient requirements. Both mid-shelf (middle ramp) and marginal environments were sites of accumulation of rich phosphatic units with high concentrations of trace elements. Deposits from marginal areas have the most varied geochemistry, largely because they experienced greater variability in terrigenous sediment influx. Even moderate changes in sea level may have dramatically altered energy levels, sediment mixing, and the amount of organic detritus reaching the sediment surface in these shallower marginal areas.

Colorado, Idaho, Montana, Nebraska, North Dakota, ↗
USGS2025

Negative growth in body mass of trout and salmon in a small stream network

In species inhabiting stressful environments, some individuals experience negative growth in body mass during their lives, potentially influencing survival, reproduction, populations, and ecosystems. Using data from a long-term (1997–2015) study of brook trout ( Salvelinus fontinalis ), brown trout ( Salmo trutta ), and juvenile Atlantic salmon ( Salmo salar ) in Massachusetts, USA, we analyzed the frequency, causes, and consequences of seasonal mass loss. Negative growth occurred in 14.8% of observations (3573 instances), with the highest prevalence during summer (June–September). Species differed markedly: 42.5% of juvenile Atlantic salmon, 24.9% of brook trout, but only 7.7% of brown trout exhibited negative growth. The likelihood of mass loss increased with size, age, and low stream flows, particularly in summer. Brook trout in the small or isolated tributaries exhibited less summer mass loss than those in the larger streams. Other factors, including temperature and population density, had minimal or inconsistent effects. Individuals experiencing negative growth, especially brook trout in summer and autumn, were less likely to be re-encountered. As we observed no association of mass loss with movement, this suggests a potential survival cost of negative body mass growth.

Massachusetts↗
USGS2013

Theoretical life history responses of juvenile Oncorhynchus mykiss to changes in food availability using a dynamic state-dependent approach

Marine subsidies can play an important role in the growth, survival, and migratory behavior of rearing juvenile salmonids. Availability of high-energy, marine-derived food sources during critical decision windows may influence the timing of emigration or the decision to forego emigration completely and remain in the freshwater environment. Increasing growth and growth rate during these decision windows may result in an altered juvenile population structure, which will ultimately affect the adult population age-structure. We used a state dependent model to understand how the juvenile Oncorhynchus mykiss population structure may respond to increased availability of salmon eggs in their diet during critical decision windows. Our models predicted an increase in smolt production until coho salmon eggs comprised more than 50 percent of juvenile O. mykiss diet at the peak of the spawning run. At higher-than intermediate levels of egg consumption, smolt production decreased owing to increasing numbers of fish adopting a resident life-history strategy. Additionally, greater growth rates decreased the number of age-3 smolts and increased the number of age-2 smolts. Increased growth rates with higher egg consumption also decreased the age at which fish adopted the resident pathway. Our models suggest that the introduction of a high-energy food source during critical periods of the year could be sufficient to increase smolt production.

Open-File Report↗
USGS2024

Integrating genetic and demographic data to refine indices of abundance for Atlantic sturgeon in the Hudson River, New York

Critical to Atlantic sturgeon Acipenser oxyrinchus oxyrinchus recovery and monitoring is the ability to estimate abundance and identify age- and stock-specific threats to survival. As adult Atlantic sturgeon spend much of their lives broadly distributed in marine and estuarine environments, it is challenging to collect data needed to estimate these demographic parameters in the adult population. Alternatively, data collected from juveniles and subadults before emigration may be used to calculate indices of abundance and provide insights into recruitment dynamics and stage-specific survival. However, uncertainty about stock mixture during early life stages may limit the use of juvenile and subadult data for monitoring recovery. To better understand early life stage stock composition, we conducted a genetic mixed-stock analysis of over 500 juvenile and subadult Atlantic sturgeon captured in an overwintering area in the Hudson River, New York, USA, from 2017 to 2022. The majority of Atlantic sturgeon in our study were natal to the Hudson River population, regardless of sex, size, or age. As such, indices of relative abundance estimated from survey data are expected to primarily characterize the demographic trends of Hudson River juvenile and subadult Atlantic sturgeon. We also found a small proportion of individuals that were most likely to have originated from more distantly located rivers, highlighting the potential for long-distance migration in juvenile and subadult Atlantic sturgeon. Results of this study strengthen our understanding of juvenile and subadult Atlantic sturgeon habitat use in the Hudson River and improve our ability to use data from early age classes to monitor recovery and stage-specific survival.

New York↗
USGS2020

Calibrating environmental DNA metabarcoding to conventional surveys for measuring fish species richness

The ability to properly identify species present in a landscape is foundational to ecology and essential for natural resource management and conservation. However, many species are often unaccounted for due to ineffective direct capture and visual surveys, especially in aquatic environments. Environmental DNA metabarcoding is an approach that overcomes low detection probabilities and should consequently enhance estimates of biodiversity and its proxy, species richness. Here, we synthesize 37 studies in natural aquatic systems to compare species richness estimates for bony fish between eDNA metabarcoding and conventional methods, such as nets, visual census, and electrofishing. In freshwater systems with fewer than 100 species, we found eDNA metabarcoding detected more species than conventional methods. Using multiple genetic markers further increased species richness estimates with eDNA metabarcoding. For more diverse freshwater systems and across marine systems, eDNA metabarcoding reported similar values of species richness to conventional methods; however, more studies are needed in these environments to better evaluate relative performance. In systems with greater biodiversity, eDNA metabarcoding will require more populated reference databases, increased sampling effort, and multi-marker assays to ensure robust species richness estimates to further validate the approach. eDNA metabarcoding is reliable and provides a path for broader biodiversity assessments that can outperform conventional methods for estimating species richness.

Frontiers in Ecology and Evolution↗
USGS2007

The need for sustained and integrated high-resolution mapping of dynamic coastal environments

The coastal zone of the United States is a dynamic environment evolving in response to both natural processes and human activities. In order to protect coastal populations and resources, a detailed understanding of the physical setting and of the processes responsible for change is required. A sustained program of mapping coastal areas provides a means to establish baseline conditions, document change, and, in conjunction with models of physical processes, predict future behavior. Recent advances in mapping technology, including airborne lidars and hyperspectral imagers, allow for the rapid collection of high-resolution elevation data and land use information on a national scale. These rich data sets are critical to evaluating risk associated with coastal hazards, such as flooding during extreme storms. For example, coastal elevation data is a fundamental parameter in storm surge models that predict where flooding will occur, and land use maps serve as the foundation of assessments that identify the resources and populations that are most vulnerable. A comprehensive, national coastal mapping plan that is designed to collect, manage, and distribute these data, as well as to take advantage of recent progress in mapping technology, will provide a wealth of information for studying the processes of physical change, for determining areas vulnerable to coastal hazards, and for protecting and managing our coastal communities and resources.

Marine Technology Society Journal↗
USGS2002

Polar Bears

Polar bears ( Ursus maritimus ) are hunted throughout most of their range. In addition to hunting polar bears of the Beaufort Sea region are exposed to mineral and petroleum extraction and related human activities such as shipping road-building, and seismic testing (Stirling 1990). Little was known at the start of this project about how polar bears move about in their environment, and although it was understood that many bears travel across political borders, the boundaries of populations had not been delineated (Amstrup 1986, Amstrup et al. 1986, Amstrup and DeMaster 1988, Garner et al. 1994, Amstrup 1995, Amstrup et al. 1995, Amstrup 2000). As human populations increase and demands for polar bears and other arctic resources escalate, managers must know the sizes and distributions of the polar bear populations. Resource managers also need reliable estimates of breeding rates, reproductive intervals, litter sizes, and survival of young and adults. Our objectives for this research were 1) to determine the seasonal and annual movements of polar bears in the Beaufort Sea, 2) to define the boundaries of the population(s) using this region, 3) to determine the size and status of the Beaufort Sea polar bear population, and 4) to establish reproduction and survival rates (Amstrup 2000).

Alaska, Northwest Territories, Yukon Territory↗
USGS2003

Patterns and processes of population change in selected nearshore vertebrate predators

Sea otters and harlequin ducks have not fully recovered from the oil spill. This project will explore links between oil exposure and the lack of population recovery, with the intent of understanding constraints to recovery of these species and the nearshore environment. In FY 02, sea otter work will include aerial surveys of distribution and abundance and estimates of age-specific survival rates. Harlequin duck field studies will examine the relationship between survival and CYP1A. Captive experiments on harlequin ducks will examine the relationships between oil exposure and CYP1A induction, and metabolic and behavioral consequences of exposure.

Report↗
USGS1999

Vegetation responses to natural regulation of elk in Rocky Mountain National Park

Little experimental information is available on the relationship between herbivory by native ungulates and vegetation in relatively undisturbed environments. A quasi-experimental situation exists in Rocky Mountain National Park, where elk (Cervus elaphus) populations have increased about 3-fold since 1968, following their release from artificial controls within the park boundaries. We reviewed data collected on vegetation transects established and monitored over the 25-year period from 1968 through 1992. Data were subjected to rigorous statistical analysis to detect trends following the release of elk from artificial controls. Increases in elk habitat use and decreases in deer habitat use were observed on all transects over the 25-year period. Significant increases in moss and lichen cover occurred in three offour vegetation types. Percent cover of bare ground, forbs (particularly Selaginella densa), and Carex spp. increased on grassland transects. Increases in timothy (Phleum pratense) were observed on meadow transects. Graminoid and litter cover increased on sagebrush transects, and shrub and litter cover increased on bitterbrush transects. We concluded the lack of control (fenced) plots in this sampling design, the types ofmeasures, the small number of replicates, and nonrandom placement of plots limit the inferences and sensitivity from the work. Unique strengths ofthe work included the long time period (25 years), good distribution of samples, consistency ofthe observer (D. Stevens), and placement of the plots in the most heavily grazed sites. Some grazing-induced responses were detected. Grazing-resistant species such as sedges (native), timothy (exotic), and club mosses increased and the amount of bare ground increased on some grazed sites. However, the changes within this sampling program alone were not alarming. The amount of bare ground increase was minor (4%), and grass and shrub cover increased in the shrub plots. The inferential power ofthis sample design was limited to the study plots only. Other factors (climate change, succession) were not controlled for using fenced plots and the sensitivity ofthe methods and plots to detect change were limited. For example, the low number oftransects in willow was not adequate to monitor conditions on the entire winter range. Lacking controls, observed changes may have been due to other factors (climate trends, beaver dam abandonment, stream channel changes), not elk herbivory alone. We recommend using a new sampling design that would include controls, pretreatment data, random site selection, and much more replication.

Colorado↗
USGS1976

An environmental assessment of impacts of coal development on the water resources of the Yampa River basin, Colorado and Wyoming; Phase II work plan

Coal resources of the western United States are being developed at everincreasing rates, causing concerns of the effects of mining and associated activities on the environment. The Yampa River basin in northwestern Colorado and south-central Wyoming is undergoing economic development of its coal, oil and gas, and uranium resources. By 1990, the annual coal mining in the basin is expected to increase to 20 million tons (18 million tonnes), or more than 4 times the 1975 level. As a result, the regional population is expected to at least double over the same period. Power-generation plants fueled by coal are being expanded or constructed in the basin and will have a combined generating capacity of nearly 1,200 megawatts by 1980. The Yampa River Basin Assessment is a 2-year program of the U.S. Geological Survey. It is designed primarily to assess the availability and quality of the basin's water resources. The basin assessment also will evaluate potential environmental and selected socioeconomic impacts of energy-resource development plans proposed by mining and power companies. This report serves as a project work plan for the basin assessment. It describes the program objectives, and the various approaches of analysis and evaluation. Environmental studies are outlined for analyzing both the direct effects of various proposals regarding coal mining, transportation, and conversion, and the secondary effects resulting from increased population and urban growth. Economic development in the Yampa River basin will generate higher levels of residuals which are discharged into the environment. Residuals-management encompasses the technological and economic interrelationships that should be considered to comply with Federal and State environmental-control regulations regarding air quality, water quality, and disposal of solid wastes. The basin assessment described by this report is designed to provide Federal, State, and local decision-makers with the basic environmental information needed to formulate and to evaluate policies for the development of energy resources. The techniques applied and conclusions reached in the Yampa River Basin Assessment should aid similar studies in other energy-rich basins in the western United States.

Colorado, Wyoming↗
USGS2002

Influences of herbivory and water on willow in elk winter range

Elimination of large predators and reduced hunter harvest have led to concerns that an increasing elk ( Cervus elaphus ) population may be adversely affecting vegetation on the low-elevation elk winter range of Rocky Mountain National Park, Colorado, USA. Beaver ( Castor canadensis ) and their impoundments also have declined dramatically (94%) in the same area over the past 50 years coincident with a 20% decline in willow ( Salix spp.) cover. From 1994 to 1998, we studied vegetation production responses of willow communities to elk herbivory and water availability. We estimated willow production by measuring current annual growth of shrubs in 9.3-m2 circular plots, and we measured herbaceous production by clipping vegetation within 0.25-m2 circular plots. Elk herbivory suppressed willow heights, leader lengths, annual production, and herbaceous productivity of willow communities. Water impoundment had a positive effect on herbaceous plant production, but little effect on shrubs, possibly because water tables were naturally high on the study sites even without beaver dams. Nevertheless, the winter range environment previously included more riparian willow habitat because of more stream area (47-69%) due to larger beaver populations. Elk herbivory appears to be the dominant force determining vegetation productivity in willow sites, but the effects may be exacerbated by lowered water tables. Fewer elk or protection from browsing, and water enhancement for <10 years along with management to encourage elk movement away from willow communities, could possibly work as strategies to reestablish sustainable willow communities.

Colorado↗
USGS2019

Characterizing urban butterfly populations: The case for purposive point-count surveys

Developing effective butterfly monitoring strategies is key to understanding how butterflies interact with urban environments, and, in turn, to developing local conservation practices. We investigated two urban habitat types (public gardens and restored/reconstructed prairies) and compared three survey methods (Pollard transects, purposive point counts, and random point counts) to determine which was most productive for detecting butterflies and assessing family diversity. We conducted 66 butterfly surveys by using each method (198 total) from May through September in 2015 and 2016 at six sites (three public gardens and three prairie areas) in Ames, Ankeny and Des Moines, Iowa. All survey methods were used on 11 sampling dates at each site. Overall, we observed 2,227 butterflies representing 38 species: 1,076 in public gardens and 1,151 in prairie areas. We used a smaller data set standardized for survey effort, including 1,361 of these sightings, to compare survey methods and habitat types. Although there were no significant differences in number of butterfly sightings between the two habitats, more sightings (798) were documented by using purposive point counts when compared to Pollard transects (297) or random point counts (266) (for both comparisons, p < 0.0001). Occupancy modeling also indicated that purposive point counts were most effective in detecting certain species of butterflies, most notably those within the Pieridae (whites, sulphurs) and Papilionidae (swallowtails). We conclude that public gardens and restored/reconstructed prairies in urban settings can provide important butterfly habitat, and that purposive point-count surveys are most effective for detecting butterflies in these relatively small-scale landscape features.

Iowa↗
USGS2022

Experimental inoculation trial to determine the effects of temperature and humidity on White-nose Syndrome in hibernating bats

Disease results from interactions among the host, pathogen, and environment. Inoculation trials can quantify interactions among these players and explain aspects of disease ecology to inform management in variable and dynamic natural environments. White-nose Syndrome, a disease caused by the fungal pathogen, Pseudogymnoascus destructans ( Pd ), has caused severe population declines of several bat species in North America. We conducted the first experimental infection trial on the tri-colored bat, Perimyotis subflavus , to test the effect of temperature and humidity on disease severity. We also tested the effects of temperature and humidity on fungal growth and persistence on substrates. Unexpectedly, only 37% (35/95) of bats experimentally inoculated with Pd at the start of the experiment showed any infection response or disease symptoms after 83 days of captive hibernation. There was no evidence that temperature or humidity influenced infection response. Temperature had a strong effect on fungal growth on media plates, but the influence of humidity was more variable and uncertain. Designing laboratory studies to maximize research outcomes would be beneficial given the high costs of such efforts and potential for unexpected outcomes. Understanding the influence of microclimates on host–pathogen interactions remains an important consideration for managing wildlife diseases, particularly in variable environments.

Scientific Reports↗
USGS2026

Waterfowl move less in heterogeneous and human-populated landscapes, with implications for spread of avian influenza viruses

Animal movements contribute to the spread of infectious diseases and are driven in part by environmental conditions. We investigated the links among the environment, animal movement, and infectious disease dynamics in waterfowl, which are among the primary wildlife hosts of avian influenza viruses. By combining telemetry data on 4606 individuals from 26 waterfowl species with data on land cover, weather, and vegetation, we found that waterfowl moved less in areas of higher land cover heterogeneity and higher human population density. Moreover, predicted waterfowl movement distances were weakly but positively correlated with distances between detections of H5N1 highly pathogenic avian influenza in wild waterfowl, suggesting that environmental conditions might contribute to the spread of this disease via their effects on bird movements. By considering wildlife movements alongside other drivers of infectious disease dynamics, such as livestock production and human mobility, we move closer to predicting outbreaks and informing interventions.

Ecology Letters↗
USGS2017

The role of the North American Breeding Bird Survey in conservation

The North American Breeding Bird Survey (BBS) was established in 1966 in response to a lack of quantitative data on changes in the populations of many bird species at a continental scale, especially songbirds. The BBS now provides the most reliable regional and continental trends and annual indices of abundance available for >500 bird species. This paper reviews some of the ways in which BBS data have contributed to bird conservation in North America over the past 50 yr, and highlights future program enhancement opportunities. BBS data have contributed to the listing of species under the Canadian Species at Risk Act and, in a few cases, have informed species assessments under the U.S. Endangered Species Act. By raising awareness of population changes, the BBS has helped to motivate bird conservation efforts through the creation of Partners in Flight. BBS data have been used to determine priority species and locations for conservation action at regional and national scales through Bird Conservation Region strategies and Joint Ventures. Data from the BBS have provided the quantitative foundation for North American State of the Birds reports, and have informed the public with regard to environmental health through multiple indicators, such as the Canadian Environmental Sustainability Indicators and the U.S. Environmental Protection Agency's Report on the Environment. BBS data have been analyzed with other data (e.g., environmental, land cover, and demographic) to evaluate potential drivers of population change, which have then informed conservation actions. In a few cases, BBS data have contributed to the evaluation of management actions, including informing the management of Mourning Doves ( Zenaida macroura ), Wood Ducks ( Aix sponsa ), and Golden Eagles ( Aquila chrysaetos ). Improving geographic coverage in northern Canada and in Mexico, improving the analytical approaches required to integrate data from other sources and to address variation in detectability, and completing the database, by adding historical bird data at each point count location and pinpointing the current point count locations would further enhance the survey's value.

Condor↗