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At least 19 recordsLinked to original sources
USGS2021

Great American Outdoors Act Legacy Restoration Fund for National Parks: Economic impacts of fiscal year 2021 funding

The Great American Outdoors Act of 2020 (GAOA), P.L. 116-152, established the National Parks and Public Land Legacy Restoration Fund (LRF) to address priority deferred maintenance projects on National Park Service (NPS) and other federal lands. For the NPS, the LRF equates to receiving a maximum of $1.33 billion per year for fiscal years 2021 through 2025. Funding of this magnitude provides the NPS with the opportunity to reduce the maintenance backlog, protect critical resources, expand recreational opportunities, and focus on long-term sustainable operations for the next century. Use of these funds on NPS projects will also support jobs and business activity in local economies across the Nation. The purpose of this analysis is to present preliminary estimates of the economic impacts associated with the NPS Fiscal Year 2021 (FY21) projects supported by the LRF.

Report↗
USGS1939

Save the Great Lakes fisheries!

During the winters of 1939-40 and 1940-41, two experiments involving 456 bobwhite quail, were conducted at the Patuxent Research Refuge, Bowie, Maryland, to determine the palatability and comparative feeding value of 20 common wild quail-foods when offered as a part of a maintenance diet....2. Mortality was low on all diets, the highest occurring on that containing a mixture of bayberry and wax myrtle fruits. On all diets the birds showed increases in weight during the early winter. These gains were better maintained by birds on the wild foods than those on control diets composed entirely of cultivated feedstuffs.....3. There were statistically significant differences between the quantities of the various diets eaten.....4. For palatability and acceptability, seeds of common ragweed (Ambrosia artemisiifolia) and of shrub lespedeza (Lespedeza bicolor) were the preferred wild foods.....5. It is concluded that pen-reared bobwhite quail can be maintained successfully through winters in the vicinity of Washington, D. C., on diets containing 50 per cent of any one of the wild foods listed and 50 per cent of a high-caloric commercial seed mixture with yellow corn as the principal cereal.....6. The results of these 'cafeteria' studies, although interesting and indicative of the preferences of quail in confinement, do not necessarily represent selections that might be. made by bobwhites in the wild.

Outdoor American↗
USGS2004

Overwintered Bullfrog tadpoles negatively affect Salamanders and Anurans in native amphibian communities

We examined the interactive effects of overwintered Bullfrog ( Rana catesbeiana ) tadpoles and pond hydroperiod on a community of larval amphibians in outdoor mesocosms including American Toads ( Bufo americanus ), Southern Leopard Frogs ( Rana sphenocephala ), and Spotted Salamanders ( Ambystoma maculatum ) - species within the native range of Bullfrogs. Spotted Salamanders and Southern Leopard Frogs were negatively influenced by the presence of overwintered Bullfrogs. Spotted Salamanders had shorter larval periods and slightly smaller masses at metamorphosis, and Southern Leopard Frogs had smaller masses at metamorphosis when reared with Bullfrogs than without. Presence of overwintered Bullfrogs, however, did not significantly affect American Toads. Longer pond hydroperiods resulted in greater survival, greater size at metamorphosis, longer larval periods, and later time until emergence of the first metamorphs for Southern Leopard Frog tadpoles and Spotted Salamander larvae. Our study demonstrated that overwintered Bullfrog tadpoles can respond to changing pond hydroperiods and can negatively impact metamorphosis of native amphibians.

Missouri↗
USGS2004

Colorado Canyons National Conservation Area 2003 visitor use survey: Completion report

This report represents the analysis of research conducted by the U.S. Geological Survey (USGS) for the Bureau of Land Management (BLM). The purpose is to provide socio-economic and recreational use information that can be used in the development of a Resource Management Plan (RMP) for the Colorado Canyons National Conservation Area (CCNCA). The results reported here deal primarily with recreation-based activities in four areas: Kokopelli Loops, Rabbit Valley, Loma Boat Launch, and Devil’s Canyon. In the fall of 2002, researchers from the Policy Analysis and Science Assistance Program (PASA) of the Fort Collins Science Center (FORT) in the USGS met with the staff of the CCNCA to discuss the issues related to social, economic, and human dimensions of natural resource management related to the RMP. As a result, a research study was designed to investigate the recreational experiences of visitors and their attitudes toward the management of the conservation area. In the spring of 2003, PASA conducted an intercept survey of recreational users at the CCNCA and a mail survey of local residents who were actively involved in decision-making regarding recreation on public lands in Mesa County, Colorado. Two hundred and three (203) mail surveys (66%) were returned and all of them were completed in full and considered usable. The intercept survey had a response rate with a range from 56%–64% among the four sites that were surveyed. We developed a questionnaire (OMB Control Number: 1040-0001) to answer the following questions: What are the important differences in citizens’ attitudes regarding recreation at the CCNCA? What are the factors that explain the differences in attitudes and preferences regarding recreation management of the NCA? What are citizens’ attitudes and preferences regarding their attitudes about paying a fee to visit the CCNCA? In general, respondents at all sites reported having an excellent or good recreation experience and almost all indicated that they intended to return. The results from the intercept survey indicated that across four sites 1(Kokopelli Loops, Devil’s Canyon, Loma Boat Launch, and Rabbit Valley) respondents reported support for undeveloped use and recreation restrictions to limit resource impacts. Respondents indicated that managing sites for undeveloped use was a good idea. The respondents from the mail survey generally had a positive orientation toward current management practices of the CCNCA. According to our surveys, non-motorized trail related activities were among the three most popular activities people engaged in both close to home and while away. These trail-based recreational activities included walking, running, mountain bike riding, and horseback riding. Research has shown that people participate in these activities for many reasons including learning about nature, exercising, to learning about paleontology, escaping for awhile, and socializing with family and friends (Taylor, 2000). National data indicate that larger percentages of the general American population engage in trail activities than in many other traditional outdoor activities (Cordell, 1999). Over 65% of people in the U.S. engage in walking as a recreational activity (Figure 1). We found that people wanted to experience the outdoors and the CCNCA provided a good place to do it. Trail activities are often those that people participate in on a regular basis as a way to exercise. This can make trail related activities more attractive from a management standpoint because people who participate in an activity may be more likely to be repeat visitors.

Open-File Report↗
USGS2005

Metamorphosis of two amphibian species after chronic cadmium exposure in outdoor aquatic mesocosms

Amphibian larvae at contaminated sites may experience an alteration of metamorphic traits and survival compared to amphibians in uncontaminated conditions. Effects of chronic cadmium (Cd) exposure on the metamorphosis of American toads ( Bufo americanus ) and southern leopard frogs ( Rana sphenocephala ) were determined. The two species were reared separately from shortly after hatching through metamorphosis in outdoor mesocosms (1,325-L polyethylene cattle tanks) that simulated natural ponds and enhanced environmental realism relative to the laboratory. Both species exhibited a decrease in survival with increasing initial nominal aqueous Cd concentration. Cadmium treatment did not influence mass at metamorphosis for either species when survival was included as a covariate, but increased the age at metamorphosis for the American toads. The whole body Cd content of metamorphs increased with aqueous Cd treatment level for both species, and the American toads tended to possess more elevated residues. Cadmium quickly partitioned out of the water column and accumulated in and altered the abundance of the tadpoles' diet. Cadmium-contaminated sites may produce fewer metamorphs, and those that survive will metamorphose later and contain Cd. Interspecific differences in the response variables illustrate the importance of testing multiple species when assessing risk.

Environmental Toxicology and Chemistry↗
USGS2022

Invasive plant hitchhikers: Appalachian Trail thru-hiker knowledge and attitudes of invasive plants and Leave No Trace practices

Hiking and backpacking on American National Scenic Trails has increased in popularity in recent years. To encourage responsible and sustainable outdoor recreation on these much-loved trails, direct and indirect management strategies must be employed by managerial agencies. The Leave No Trace (LNT) education program aims to protect natural resources by promoting minimum-impact behaviours that lessen environmental impacts. The accidental introduction and dispersal of non-native invasive flora by hikers is little studied but can have a detrimental environmental impact on protected areas. The purpose of our study was to understand whether Appalachian Trail thru-hikers are: 1) aware of this problem, 2) adhering to LNT principles to reduce this problem, and 3) willing to learn and adopt minimum-impact behaviours to address this problem. We found that thru-hiker knowledge of invasive plants was limited and that very few thru-hikers adopted low-impact practices to minimise plant introduction and spread. Promisingly, we found that most thru-hikers, once aware of the problems, were willing to learn and apply low-impact practices to minimise plant introduction and spread. We discuss the barriers to their adoption of these behaviours and present a comprehensive list of suggested LNT practices to limit invasive plant introduction and spread. We conclude that, whilst challenging, protected area managers can help deter the spread of invasive plants along trails by improving educational messaging, signage, personal communication, and providing supporting infrastructure that encourages visitors to adopt specific practices to minimise invasive plant introduction and spread within protected areas.

Virginia, West Virginia↗
USGS2003

Interactions of an insecticide, herbicide, and natural stressors in amphibian community mesocosms

Amphibians developing in wetlands embedded within or near agricultural lands may frequently encounter chemical mixtures. The objectives of our study were to determine the effects that post-application concentrations of an insecticide (carbaryl) and an herbicide (atrazine) have on body mass, development, and survival of two anuran species (southern leopard frog, Rana sphenocephala ; American toad, Bufo americanus ) and two caudate species (spotted salamander, Ambystoma maculatum ; small-mouthed salamander, A. texanum ) reared in outdoor cattle tank mesocosms. In one experiment, we manipulated tadpole density (low or high), carbaryl exposure (0, 3.5, 7.0 mg/L), and atrazine exposure (0 or 200 μg/L) to test for effects on development, mass, and survival of larvae. In a second experiment, we manipulated pond hydroperiod (constant or drying), carbaryl exposure (0 or 5 mg/L), and atrazine exposure (0 or 200 μg/L) to test for effects on mass, time, and survival to metamorphosis. Salamanders were virtually eliminated in carbaryl treatments, indicating that at realistic levels, this insecticide could cause population declines for salamanders in contaminated habitats. Carbaryl also had negative effects on toad survival. Exposure to atrazine had negative effects on body size, development, and time to metamorphosis in anuran species, which were associated with reduced chlorophyll levels. Both chemicals interacted significantly with density or hydroperiod, indicating that the environmental conditions could influence the impact of a contaminant. A significant atrazine-by-carbaryl interaction resulted in smaller and less developed spotted salamander larvae than in control ponds. Atrazine exposure, however, appeared to moderate negative effects of carbaryl for spotted salamanders. Our research suggests that important changes in the community's food web result from chemical exposure, which influence the susceptibility of amphibian species to contaminants.

Ecological Applications↗
USGS1982

HEP as a planning tool: an application to waterfowl enhancement

To many, the principal role of wildlife agencies in public and private resource development has been that of impact mitigation. With known or pending habitat damage, biologists have to develop mitigation or compensation plans. Unfortunately, once in a mitigation framework, they are in a no-win situation, seeking remedial action at best. Yet, the potential exists for cooperative project planning, thereby facilitating mitigation of impacts before they occur, and enhancement of environmental amenities through project development. In fact, such planning is mandated by federal legislation (e.g., National Environmental Policy Act, Fish and Wildlife Coordination Act, Outdoor Recreation Act, etc.).

Transactions of the North American Wildlife and Na↗
USGS2025

USGS—An Unparalleled Scientific Asset

The U.S. Geological Survey (USGS) delivers information critical to powering our economy, managing our natural resources, and keeping Americans safe and healthy. 1 Mapping the Nation $21B Geologic maps save users an estimated 15% in annual costs: a value of between $14B and $21B. $25.6B in annual value to users of imagery from Landsat satellites, which were codeveloped by NASA and the USGS and operated through their lifespans by the USGS. $13.5B in annual benefits is generated by the USGS's 3D Elevation Program. Securing America’s Energy Independence 44% USGS-identified undiscovered geothermal energy is equal to 44% of current U.S. electricity generation. 29.4B barrels of oil and 391.6 trillion cubic feet of gas in recoverable resources are available on U.S. public lands based on USGS assessments. Protecting Americans’ Health and Safety $424B in recent wildland fire damages highlight the need for USGS fire science, which supports efforts to protect communities and reduce risk. USGS earthquake, volcano, landslide, and coastal hazard monitoring and information save lives and minimize costs; for example, $2.8M can be saved because of USGS enhanced information about a Mauna Loa eruption. $4.5B is the estimated cost of annual flooding. Through a network of over 11,885 streamgages, the USGS supports public safety and enables forecasts, early warning systems, and management actions that protect lives and property. Supporting National Security $3.1B The USGS identified a $3.1B risk to the American economy if China restricts gallium imports. This is one example underscoring the importance of the USGS mapping critical minerals, investigating supply chains, and producing the Nation’s critical minerals list. Enhancing Our Lands and Waters $21B in estimated annual costs results from invasive species. The USGS’s invasive species research informs approaches used to reduce their effects on agriculture, water infrastructure, disease transmission, fisheries, and outdoor recreation. USGS innovations support early warnings for harmful algal blooms—over $2M in yearly benefits are provided to Kansas alone. $45B USGS science informs the management of big game (such as deer and elk). The big-game hunting industry contributes $45B to the U.S. economy. Fostering American Prosperity $4.1T Mineral commodities are necessary for the $4.1T in value added to the GDP by major industries that consume processed mineral materials and employ 1 million workers. Because of this, USGS data on mineral supply, demand, and trade are highly valued. 45,000 metric tons Rare earths power the growing technology economy, including cell phones, electric vehicles, and medical devices. For over 70 years, USGS work has supported the discovery of rare earth resources in California’s Mountain Pass area, which produced 45,000 metric tons of rare earth concentrates in 2024—over 11% of the global supply. Guarding American Food Security $70.2B USGS science informs early warning systems and management strategies to mitigate disease outbreaks in agriculture—critical research on highly pathogenic avian influenza, for example, helps safeguard the $70B value in poultry and egg production. $11.8B USGS groundwater tools are vital for agriculture; for example, in the Mississippi Alluvial Plain, 65% of farming relies on groundwater to support its $11.8B annual industry. 1 Values throughout are given in billions (B), millions (M), and trillions (T) of U.S. dollars. GDP is “Gross Domestic Product.” Percentages are shown as %.

General Information Product↗
USGS2025

A nationwide evaluation of crowd-sourced ambient temperature data

Growing concerns about heat in urban areas paired with the sparsity of weather stations have resulted in individuals drawing on data from citizen science sensor networks to fill in data gaps. The PurpleAir are the most widely-used low-cost air quality sensors in the contiguous United States with 14,777 deployed between 1 Jan 2017 and 20 July 2021. Although the air quality data from PurpleAir sensors have been widely studied, less attention has been paid to reported temperature. We compare temperature metrics reported by PurpleAir sensors with a gridded temperature product, the North American Land Data Assimilation System (NLDAS)-2, which although not a gold-standard measure of temperature, is widely used in epidemiologic research. We evaluate the lag between indoor and outdoor PurpleAir temperatures. We report associations of the difference between outdoor PurpleAir temperatures and NLDAS-2 temperatures, an indicator of degradation, and the duration of sensor operation. Finally, based on the temperature range recorded by the outdoor PurpleAir sensors vis.a.vis NLDAS-2 temperatures, we provide a list of 271 (2.5%) sensors potentially misclassified as outdoor and likely located indoors. We observed that outdoor PurpleAir sensors agreed well with NLDAS-2 (R2 > 0.82). This association broke down under warm conditions (daily average NLDAS ≥ 21.1oC). Landcover and climate zone were significant modifiers of the association between PurpleAir and NLDAS-2 temperature metrics with the poorest PurpleAir- NLDAS-2 agreement in urban areas. Indoor PurpleAir temperatures lagged hourly NLDAS temperatures by two hours across almost all climate zones. The mean difference in hourly PurpleAir and NLDAS-2 temperatures increased by 0.57oC for every operational year, suggesting that careful attention must be paid to degradation. Overall, we find for use in epidemiological studies, that the PurpleAir sensor data is a reliable metric of daytime mean air temperature, but researchers should be aware of its limitations when examining extreme heat, or when aggregating sensor data across multiple years.

Frontiers of Environmental Science and Engineering↗
USGS1970

Propagation of captive American kestrels

A colony of kestrels ( Palco sparverius ) was established at the Patuxent Wildlife Research Center in 1964 in connection with work on pesticides. The kestrels were acquired from the wild, both as nestlings and as full-grown birds, and were housed in several rows of outdoor pens. Each 50 x 20 ft pen was covered with wire netting and had its long sides in common with adjacent pens. During the first two reproductive seasons, untreated parent birds (dosed birds are not included in this paper) ate eggs and young. Cannibalism virtually ceased after the diet was changed from ground beef or horsemeat supplemented with liver, vitamins, and minerals to one containing a finely ground mixture of laboratory rodents, chicken heads, skinned chicken necks, and supplements; hatching success thereafter generally equaled that of a wild population. In 1967, 16 pairs of untreated hawks (3-year-old females) laid clutches averaging 4.9 eggs, hatched 88 percent of their eggs, and fledged 88 percent of their young. In 1968, 10 pairs of this group (4-year-old females) laid clutches averaging 4.9 eggs, hatched 51 percent of their eggs, and fledged 85 percent of their young. Nine yearling pairs (hatched in captivity) laid clutches in 1968 averaging 5.1 eggs, hatched 87 percent of their eggs, and fledged all of their young.

Maryland↗
USGS2018

Volcanic eruptions and threats to respiratory health

In early May 2018, Kīlauea volcano became increasingly active, posing an increase in threat to respiratory health. The emission of gases such as sulfur dioxide from Kīlauea produces large amounts of respirable acid particles as the gases react with water vapor and sunlight, resulting in a visible haze called “vog”. Additionally, the lava lake at Kīlauea’s summit crater has fallen, leading to explosions of “ash” that have reached as high up as 30,000 feet above sea level. Finally, lava entering the Pacific Ocean boils sea water to dryness, creating thick clouds of “laze” that is filled with hydrochloric acid and tiny shards of glass. Depending on your location and wind direction and speed, vog, ash, and laze can reach hazardous levels of air pollution that are toxic to humans. This fact sheet serves to inform you of potential adverse health effects following exposure to these airborne products of volcanic activity. This outdoor air quality issue is relevant to other locations worldwide at risk for volcanic activity.

American Journal of Respiratory and Critical Care ↗
USGS1993

Monitoring and research at Walnut Creek National Wildlife Refuge

Walnut Creek National Wildlife Refuge-Prairie Learning Center (Walnut Creek or the Refuge) is one of the newest additions to the National Wildlife Refuge System, which consists of over 480 units throughout the United States operated by the U.S. Department of the Interior, Fish and Wildlife Service (the Service). Located about 20 miles east of Des Moines, Iowa, the Refuge has an approved acquisition boundary containing 8,654 acres (Figure 1). Acquisition is from willing sellers only, and to date the Service has purchased approximately 5,000 acres. The acquisition boundary encompasses about 43% of the watershed of Walnut Creek, which bisects the Refuge and drains into the Des Moines River to the southeast. Approximately 25%-30% of the Walnut Creek watershed is downstream of the Refuge. As authorized by Congress in 1990, the purposes of the Refuge are to (U.S. Fish and Wildlife Service 1992): • restore native tallgrass pairie, wetland, and woodland habitats for breeding and migratory waterfowl and resident wildlife; • serve as a major environmental education center providing opportunities for study; • provide outdoor recreation benefits to the public; and • provide assistance to local landowners to improve their lands for wildlife habitat. To implement these purposes authorized by Congress, the Refuge has established the goal of recreating as nearly as possible the natural communities that existed at the time of settlement by Euro-Americans (circa 1840). Current land use is largely agricultural, including 69% cropland, 17% grazed pasture, and 7.5% grassland (dominantly brome) enrolled in the Conservation Reserve Program). About 1,395 acres of relict native communities also exist on the Refuge, including prairie (725 acres), oak savanna and woodland (450 acres), and riparian or wetland areas (220 acres). Some of these relicts are highly restorable; others contain only a few prairie plants in a matrix of brome and will be more difficult to restore. When the process of restoration (management and enhancement of existing remnant communities) and reconstruction (reestablishment of native communities on agricultural sites) is completed, it is anticipated that the Refuge will consist of approximately 5,900 acres of prairie, 2,000 acres of oak savanna or woodland, and 750 acres of wetland and riparian communities. Ecological restoration and reconstruction at this scale in the tallgrass prairie ecosystem is unprecedented in the United States.

Report↗
USGS2024

Perceived constraints to participating in wildlife-related recreation

Wildlife-related recreationists play an important role in conservation. Understanding constraints to wildlife-related activities is critical for maintaining or increasing participation in activities like birdwatching and hunting. A mail-out survey was administered to a generalized sample representative of U.S. residents (i.e., not specific to birdwatching or hunting) in early 2017 to determine what would limit them from participating in birdwatching and hunting (n = 1030). We employed a concurrent nested mixed-methods design: open-ended responses were thematically coded qualitatively in two distinct cycles (i.e., inductive, and then mixed inductive-deductive coding), and then the probability of expressing the second cycle codes was quantitatively modeled using multinomial logit models for the respective activities. Doing so empirically determined various groups’ constraints that are important to recruitment, retention, and reactivation (R 3 ) efforts for birdwatching and hunting. We found that the likelihood of experiencing unique constraints varied based on sociodemographic characteristics, and these relationships differed between birdwatching and hunting. Gender had a limited effect on constraints to birdwatching but was a strong indicator of intrapersonal constraints and limitations to involvement in hunting. The likelihood of expressing structural constraints decreased with age for both activities. Possessing strong social ties to the activities tended to reduce the likelihood of expressing constraints overall but this was especially true for hunting. Our findings inform R 3 efforts for wildlife-related recreation and provide direct results that organizations can apply in seeking to help Americans negotiate constraints and increase and diversify participation in wildlife-related recreation and conservation behavior.

Journal of Outdoor Recreation and Tourism↗
USGS2001

Intermittent feeding in a migratory omnivore: Digestion and body composition of American Black Duck during autumn

Birds fast intermittently during weather disturbances and migration. We tested responses of black duck to lost feeding days during autumn mass gain. Nine adult males were fed a pelleted diet (1.5% fat, 15.8% protein, and 18.3% neutral detergent fiber) and caged indoors during September and October (12 h light; 17°–24°C) to measure balances over 14 d when fed ad lib. each day and fasted intermittently for 2 d wk −1 (short fast) or 4 d wk −1 (long fast). Body mass (1,081 g), body water content, and metabolizable intakes of energy and protein were maintained as daily intakes of dry matter increased to 1.65 (short fast) and 2.35 (long fast) times the unfasted level. Intermittent feeding reduced metabolizability of dry matter, energy, protein, and acid detergent fiber. Concentrations of Mn provided similar estimates of metabolizability to direct measures in unfasted birds but underestimated measures of birds on long fasts. Fasting regimes continued outdoors for 9 wk when temperatures declined to −9°C. Birds on short fasts were heavier (1,373 vs. 1,241 g) and fatter (159 vs. 58 g) than those on long fasts, while body water (894 g) and protein (316 g) were similar between groups after 5 wk. Birds on long fasts subsequently gained mass when fed daily, but those on short fasts lost mass when fed each day. Omnivorous waterfowl combine ingestive and digestive flexibility with plasticity of body lipid to contend with uncertain food availability.

Physiological and Biochemical Zoology↗
USGS2012

Feeding response of sport fish after electrical immobilization, chemical sedation, or both

Fishery managers frequently capture wild fish for a variety of fishery management activities. Though some activities can be accomplished without immobilizing the fish, others are accomplished more readily, humanely, and safely (for both the handler and the fish) when fish are immobilized by physical (e.g., electrical immobilization) or chemical sedation. A concern regarding the use of chemical sedatives is that chemical residues may remain in the fillet tissue after the fish recovers from sedation. If those residues are harmful to humans, there is some risk that a postsedated fish released to public waters may be caught and consumed by an angler. To characterize this risk, a series of four trials were conducted. Three trials assessed feeding activity after hatchery-reared fish were electrically immobilized, chemically sedated, or both, and one trial assessed the likelihood of an angler catching a wild fish that had been electrically immobilized and chemically sedated. Results from the first trial indicated that the feeding activity of laboratory habituated fish was variable among and within species after electrical immobilization, chemical sedation, or both. Results from the second trial indicated that the resumption of feeding activity was rapid after being mildly sedated for 45 min. Results from the third trial indicated that the feeding activity of outdoor, hatchery-reared fish was relatively aggressive after fish had been chemically sedated. Results from the fourth trial indicated that the probability of capturing wild fish in a more natural environment by angling after fish had been electrically immobilized and chemically sedated is not likely, i.e., in a group of five fish caught, 3 out of 100 times one would be a fish that had been sedated.

North American Journal of Fisheries Management↗