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USGS2020

Hydrologic conditions in Kansas, water year 2019

The U.S. Geological Survey Kansas Water Science Center, in cooperation with Federal, State, and local agencies, maintains a long-term network of hydrologic monitoring stations in the State of Kansas. These include a network of 217 real-time streamgages and 12 real-time reservoir-level monitoring stations in water year 2019. The data and associated analyses from the streamgages and monitoring stations provide a unique overview of hydrologic conditions and help improve the understanding of Kansas’ water resources. Annual assessments of hydrologic conditions are made by comparing statistical analyses of current and past water year data for the period of record. Long-term monitoring of hydrologic conditions in Kansas provides imperative information for many uses including managing water resources and protecting human life and property and promoting agricultural practices, industrial activities, operation of reservoirs , development of infrastructure, ecological assessments, and recreational purposes.

Kansas↗

USGS2005

GIS compilation of data collected from the Pulley Ridge Deep Coral Reef region

Pulley Ridge is a chain of drowned barrier islands that extends almost 200 km in 60-90 m water depths (Fig. 1). This drowned ridge is located on the Florida Platform in the southeastern Gulf of Mexico about 250 km west of Cape Sable, Florida (Jarrett and others, 2005). These islands formed during the early Holocene marine transgression approximately 12,000 - 14,000 years before present, and were then submerged by sea level rise and preserved near the outer edge of the Florida Platform. The southern portion of Pulley Ridge is the focus of this study. This area hosts zooxanthellate scleractinian corals, green, red and brown macro algae, and a mix of deep and typically shallow-water tropical fishes. This largely photosynthetic community is unique in that it thrives with less than 5% of the light typically associated with shallow-water reefs with similar fauna. Several factors help to account for the existence of this unique deep-water community. First, the underlying drowned barrier islands provide both elevated topography and lithified substrate for the establishment of the hardbottom community. Second, the region is commonly bathed by the Loop Current, which brings relatively clear and warm water to this area. Third, the ridge's position on the continental shelf places it within the thermocline which provides nutrients to the reef during upwelling (Halley and others, 2003). The USGS has made two proposals to resource managers for the designation of marine protected areas based on the geophysical and photographic data in this report. The proposals describe areas that may require some regulatory protection of marine life utilizing the sea floor (Fig. 1). The first proposal is that the area of greatest hermatypic coral cover (Fig. 1) is considered for future management actions and designated a Habitat Area of Particular Concern (HAPC) by the Gulf of Mexico Fishery Management Council. HAPCs are identified on the basis of habitat level considerations: The importance of the ecological function provided by the habitat. The extent to which the habitat is sensitive to human-induced environmental degradation. Whether and to what extent development activities are or will be stressing the habitat. The rarity of the habitat type. The second proposed area is for Coral Essential Fish Habitat (CEFH, Fig. 1). CEFHs are defined as "those waters and substrate necessary to corals for spawning, breeding, feeding, or growth to maturity." The following definitions are provided for clarification: waters is defined as "aquatic areas and their associated physical, chemical, and biological properties that are used by corals" substrate means "sediment, hard bottom, structures underlying the waters, and associated biological communities" necessary means "the habitat required to support a sustainable population and the managed species' contribution to a healthy ecosystem" spawning,breeding, feeding, or growth to maturity covers the full life cycle of a species. The CEFH shown in Figure 1 is the greatest coral cover in the region as determined by the bottom photo and video transects acquired during this study. This report presents the geophysical and photographic data that were collected to describe the surficial and shallow subsurface geologic framework of the area where these deep-water corals are known to occur. The data types include multibeam bathymetry, sidescan-sonar imagery, images of high-resolution seismic-reflection profiles, and bottom photographs. In addition, the tracklines for the seismic data, locations of bottom photographs and camera drifts, and tracklines along which submersible and remotely operated vehicle (ROV) observations were made are contained in the GIS files accompanying this report. Unfortunately, video footage from the camera drifts, submersible, and ROV cruises is not available on this DVD due to the quantity of data. The bottom photograph data set has been previously published (Cross and others, 2004), however it is included in this publication in an effort to integrate the varying data sets in one location. This integration is accomplished through the GIS data included on this DVD.

Florida↗

USGS2025

Assessment of treated wastewater infiltration in Bright Angel Wash and the potential for contaminants of emerging concern influencing spring water quality along the South Rim of the Grand Canyon in Grand Canyon National Park, Arizona

In April 2021, a synoptic study conducted by the U.S. Geological Survey (USGS) and National Park Service (NPS) identified wastewater-related contaminants of emerging concern (CECs) in springs along the South Rim of the Grand Canyon. These springs are located north of Bright Angel Wash, an ephemeral channel that receives treated effluent from the South Rim Wastewater Treatment Plant (SRWTP). Although water flows southwest and away from the canyon, there is evidence that treated wastewater is finding a flow path along fractures associated with the Bright Angel Fault back to water sources along the South Rim. The CECs identified during the April 2021 sampling included several per- and polyfluoroalkyl substances (PFAS) and pharmaceutical compounds. The PFAS compounds detected only consisted of perfluoroalkyl acids, and these were only detected at Bright Angel Wash (treated wastewater), Monument Spring, and upper Horn Bedrock Spring. The other five sampled springs (the Salt Creek, Horn East Alluvium, Garden, Pumphouse, and Pipe Springs) had no detections of PFAS compounds. The five perfluoroalkyl acids detected at Monument Spring (in descending order of concentration) were perfluorobutanesulfonic acid (PFBS), perfluoropentanoic acid, perfluorooctanoic acid, perfluorohexanoic acid, and perfluorooctanesulfonic acid. Only the short-chained PFBS and perfluorobutanoic acid compounds were detected at the upper Horn Bedrock Spring. All the same perfluoroalkyl acids were found at Bright Angel Wash, except for PFBS. Monument Spring was the only spring to have detections of pharmaceuticals. The two pharmaceuticals detected at the highest concentrations at Monument Spring were diphenhydramine (antihistamine) and carbamazepine (anticonvulsant or anti-epileptic drug). The other detected pharmaceuticals included (in descending order of concentration) fluconazole (antifungal), sulfamethoxazole (antibiotic), metformin (diabetes drug), tramadol (opioid analgesic), and venlafaxine (antidepressant and nerve pain medication). The same pharmaceuticals were detected in the wastewater at Bright Angel Wash but in greater concentrations. No CEC concentrations measured at Monument Spring exceeded any drinking water standards or human health benchmarks; however, most of the compounds detected have no regulatory standards. Studies of the ecological effects of these compounds show that some of the compounds detected can have endocrine and physiological effects, but generally, effects were observed at concentrations multiple orders of magnitude greater than what was measured during the April 2021 study. Data from 1980 through 2022 retrieved from the Water Quality Portal were combined with data from the one-time synoptic sampling in April 2021 to assess the usefulness of other analytes for identifying a wastewater connection to South Rim springs. Most of the historical water chemistry data showed a statistical difference between samples collected within and east of the Garden Creek watershed and samples collected from locations in watersheds to the west of Garden Creek, including the Horn Creek, Salt Creek, Monument Creek, and Hermit Creek watersheds, which roughly align with the Bright Angel Fault. Most of the historical analytes were inconclusive as potential wastewater tracers, but nitrate, chloride, and gadolinium data possibly support the historical contribution of wastewater to Monument Spring.

Arizona↗

USGS2020

Building adaptive capacity in a coastal region experiencing global change

Coastal ecosystems in the eastern U.S. have been severely altered by human development, and climate change and other stressors are now further degrading the capacity of those ecological and social systems to remain resilient in the face of such disturbances. We sought to identify potential ways in which local conservation interests in the Lowcountry of South Carolina (USA) could participate in a social process of adaptation planning, and how that process might ultimately be broadened to engage a more diverse set of partners. We engaged participants through a combination of informal meetings, workshops, and other collaborative interactions to explore how the conservation community perceives and pursues its various missions, and how that community might confront the threats and opportunities in its future. Coproduction of knowledge and meaning were facilitated by collaborative scenario planning and strategic planning evaluation, which illuminated how the conservation community is integral to the broader governance of the region and highlighted how responses to forces of change are mediated through local culture, economics, and politics. We suggest an interpretation of conservation in which the fundamental objectives of both social and ecological systems might be prioritized in tandem, rather than narrowly focusing on environmental protection without consideration of the social landscape. Ultimately, adaptive capacity depends on the ability to act collectively, and social capital, trust, and organization greatly influence the capacity to act. Thus, we conclude that the presence of strong social networks, coordination and deliberation among diverse stakeholders, mechanisms for experiential feedback, and emphasis on social learning are key elements needed to build adaptive capacity. Central to the evolving perspective of governance of the commons is recognition that social and ecological systems are coupled; the issues and problems of one cannot be addressed without considering the consequences for the other. Moreover, a dominant theme emerging from our research and that of other scholars is the importance of culture and place attachment, which generates social cohesion and facilitates problem solving. These ideas have important implications for when, where, and how stakeholders are engaged to address the rapid changes being experienced by social-ecological systems.

South Carolina↗

USGS1989

Pentachlorophenol Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review

Pentachlorophenol (PCP) is now widely used as a wood preservative, and this has contributed to the detection of PCP residues in air, rain, groundwaters, surface waters, fish and aquatic invertebrates, and in human urine, blood, and milk of nursing mothers. This report briefly reviews the technical literature on ecological and toxicological aspects of PCP in the environment, with emphasis on fishery and wildlife resources. Subtopics include sources and uses, chemical properties, fate, background concentrations, lethal and sublethal effects, and current recommendations for resource protection

Contaminant Hazard Reviews↗

USGS2017

Human infectious disease burdens decrease with urbanization but not with biodiversity

nfectious disease burdens vary from country to country and year to year due to ecological and economic drivers. Recently, Murray et al. (Murray CJ et al . 2012 Lancet 380 , 2197–2223. ( doi:10.1016/S0140-6736(12)61689-4 )) estimated country-level morbidity and mortality associated with a variety of factors, including infectious diseases, for the years 1990 and 2010. Unlike other databases that report disease prevalence or count outbreaks per country, Murray et al. report health impacts in per-person disability-adjusted life years (DALYs), allowing comparison across diseases with lethal and sublethal health effects. We investigated the spatial and temporal relationships between DALYs lost to infectious disease and potential demographic, economic, environmental and biotic drivers, for the 60 intermediate-sized countries where data were available and comparable. Most drivers had unique associations with each disease. For example, temperature was positively associated with some diseases and negatively associated with others, perhaps due to differences in disease agent thermal optima, transmission modes and host species identities. Biodiverse countries tended to have high disease burdens, consistent with the expectation that high diversity of potential hosts should support high disease transmission. Contrary to the dilution effect hypothesis, increases in biodiversity over time were not correlated with improvements in human health, and increases in forestation over time were actually associated with increased disease burden. Urbanization and wealth were associated with lower burdens for many diseases, a pattern that could arise from increased access to sanitation and healthcare in cities and increased investment in healthcare. The importance of urbanization and wealth helps to explain why most infectious diseases have become less burdensome over the past three decades, and points to possible levers for further progress in improving global public health.

Philosophical Transactions of the Royal Society B:↗

USGS2011

The human dimension of fire regimes on Earth

Humans and their ancestors are unique in being a fire‐making species, but ‘natural’ (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human‐set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from ‘natural’ background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke‐related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas‐induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding of the development and diversification of fire regimes, covering the pre‐human period, human domestication of fire, and the subsequent transition from subsistence agriculture to industrial economies. All of these phases still occur on Earth, providing opportunities for comparative research.

Journal of Biogeography↗

USGS2021

Exposure to domoic acid is an ecological driver of cardiac disease in southern sea otters

Harmful algal blooms produce toxins that bioaccumulate in the food web and adversely affect humans, animals, and entire marine ecosystems. Blooms of the diatom Pseudo-nitzschia can produce domoic acid (DA), a toxin that most commonly causes neurological disease in endothermic animals, with cardiovascular effects that were first recognized in southern sea otters. Over the last 20 years, DA toxicosis has caused significant morbidity and mortality in marine mammals and seabirds along the west coast of the USA. Identifying DA exposure has been limited to toxin detection in biological fluids using biochemical assays, yet measurement of systemic toxin levels is an unreliable indicator of exposure dose or timing. Furthermore, there is little information regarding repeated DA exposure in marine wildlife. Here, the association between long-term environmental DA exposure and fatal cardiac disease was investigated in a longitudinal study of 186 free-ranging sea otters in California from 2001 – 2017, highlighting the chronic health effects of a marine toxin. A novel Bayesian spatiotemporal approach was used to characterize environmental DA exposure by combining several DA surveillance datasets and integrating this with life history data from radio-tagged otters in a time-dependent survival model. In this study, a sea otter with high DA exposure had a 1.7-fold increased hazard of fatal cardiomyopathy compared to an otter with low exposure. Otters that consumed a high proportion of crab and clam had a 2.5- and 1.2-times greater hazard of death due to cardiomyopathy than otters that consumed low proportions. Increasing age is a well-established predictor of cardiac disease, but this study is the first to identify that DA exposure affects the risk of cardiomyopathy more substantially in prime-age adults than aged adults. A 4-year-old otter with high DA exposure had 2.3 times greater risk of fatal cardiomyopathy than an otter with low exposure, while a 10-year old otter with high DA exposure had just 1.2 times greater risk. High Toxoplasma gondii titers also increased the hazard of death due to heart disease 2.4-fold. Domoic acid exposure was most detrimental for prime-age adults, whose survival and reproduction are vital for population growth, suggesting that persistent DA exposure will likely impact long-term viability of this threatened species. These results offer insight into the pervasiveness of DA in the food web and raise awareness of under-recognized chronic health effects of DA for wildlife at a time when toxic blooms are on the rise.

California↗

USGS2019

A landscape model of variable social-ecological fire regimes

Fire regimes are now recognized as the product of social processes whereby fire on any landscape is the product of human-generated drivers: climate change, historical patterns of vegetation manipulation, invasive species, active fire suppression, ongoing fuel management efforts, prescribed burning, and accidental ignitions. We developed a new fire model (Social-Climate Related Pyrogenic Processes and their Landscape Effects: SCRPPLE) that emphasizes the social dimensions of fire and enables simulation of fuel-treatment effects, fire suppression, and prescribed fires. Fire behavior was parameterized with daily fire weather, ignition, and fire-boundary data. SCRPPLE was initially parameterized and developed for the Lake Tahoe Basin (LTB) in California and Nevada, USA although its behavior is general and could be applied worldwide. We demonstrate the behavior and utility of our model via four simple scenarios that emphasize the social dimensions of fire regimes: a) Recent Historical: simulated recent historical patterns of lightning and accidental fires and current patterns of fire suppression, b) Natural-Fire-Regime: simulated wildfire without suppression, accidental fires, or prescribed fires, holding all other factors the same as Recent Historical, c) Enhanced Suppression: simulated a doubling of the effectiveness of suppression, holding all other factors the same as Recent Historical, and d) Reduced Accidental Ignitions: within which the number of accidental fires was reduced by half, holding all other factors the same as Recent Historical. Results indicate that SCRPPLE can recreate past fire regimes, including size, intensity, and locations. Furthermore, our results indicate that the ‘Enhanced Suppression’ and ‘Reduced Accidental Ignitions’ scenarios had similar capacity to reduce fire and related tree mortality over time, suggesting that within the broad outlines of the scenarios, reducing accidental fires can be as effective as substantially increasing resources for suppression.

California, Nevada↗

USGS2009

Science-Based Strategies for Sustaining Coral Ecosystems

Coral ecosystems and their natural capital are at risk. Greenhouse gas emissions, overfishing, and harmful land-use practices are damaging our coral reefs. Overwhelming scientific evidence indicates that the threats are serious, and if they are left unchecked, the ecological and social consequences will be significant and widespread. Although the primary stressors to coral ecosystems are known, science-based strategies are needed to more accurately explain natural processes and forecast human-induced change. Collaborations among managers and scientists and enhanced mapping, monitoring, research, and modeling can lead to effective mitigation plans. U.S. Geological Survey scientists and their partners assess coral ecosystem history, ecology, vulnerability, and resiliency and provide study results to decisionmakers who may devise policies to sustain coral resources and the essential goods and services they provide.

Fact Sheet↗

USGS2014

Maximizing the social and ecological value of Cape Romain National Wildlife Refuge, South Carolina as the effects of global change processes increase.

Coastal ecosystems in the eastern U.S. have been severely altered by processes associated with human development, including drainage of coastal wetlands, changes in hydrology that alter sediment and freshwater delivery to the coast, land clearing, agricultural and forestry activity, and the construction of seawalls and other structures that “harden” the coast. Sea-level rise and the changing frequency of extreme events associated with climate change are now further degrading the capacity of those ecological and social systems to remain resilient in the face of disturbance, largely through the degradation and loss of land and habitat. The goal was to develop a problem framing that would broadly reflect the type, scale and scope of SLR-adaptation decisions faced by refuges in general, and that could be used by individual refuges to help understand how their specific problems fit into a larger context of SLR planning and implementation. We worked with refuge managers in developing a common frame of reference for some shared SLR-related management problems, while also facilitating communication about these problems with other refuges and with surrounding jurisdictions.

South Carolina↗

USGS2015

Hydrology: The interdisciplinary science of water

We live in a world where biophysical and social processes are tightly coupled. Hydrologic systems change in response to a variety of natural and human forces such as climate variability and change, water use and water infrastructure, and land cover change. In turn, changes in hydrologic systems impact socioeconomic, ecological, and climate systems at a number of scales, leading to a coevolution of these interlinked systems. The Harvard Water Program, Hydrosociology, Integrated Water Resources Management, Ecohydrology, Hydromorphology, and Sociohydrology were all introduced to provide distinct, interdisciplinary perspectives on water problems to address the contemporary dynamics of human interaction with the hydrosphere and the evolution of the Earth’s hydrologic systems. Each of them addresses scientific, social, and engineering challenges related to how humans influence water systems and vice versa. There are now numerous examples in the literature of how holistic approaches can provide a structure and vision of the future of hydrology. We review selected examples, which taken together, describe the type of theoretical and applied integrated hydrologic analyses and associated curricular content required to address the societal issue of water resources sustainability. We describe a modern interdisciplinary science of hydrology needed to develop an in-depth understanding of the dynamics of the connectedness between human and natural systems and to determine effective solutions to resolve the complex water problems that the world faces today. Nearly, every theoretical hydrologic model introduced previously is in need of revision to accommodate how climate, land, vegetation, and socioeconomic factors interact, change, and evolve over time.

Water Resources Research↗

USGS2009

Shifts in lake N: P stoichiometry and nutrient limitation driven by atmospheric nitrogen deposition

Human activities have more than doubled the amount of nitrogen (N) circulating in the biosphere. One major pathway of this anthropogenic N input into ecosystems has been increased regional deposition from the atmosphere. Here we show that atmospheric N deposition increased the stoichiometric ratio of N and phosphorus (P) in lakes in Norway, Sweden, and Colorado, United States, and, as a result, patterns of ecological nutrient limitation were shifted. Under low N deposition, phytoplankton growth is generally N-limited; however, in high-N deposition lakes, phytoplankton growth is consistently P-limited. Continued anthropogenic amplification of the global N cycle will further alter ecological processes, such as biogeochemical cycling, trophic dynamics, and biological diversity, in the world's lakes, even in lakes far from direct human disturbance.

Science↗

USGS1997

Habitat associations and effects of urbanization on macroinvertebrates of a small, high-plains stream

We described the relations between abundance of macroinvertebrates and several habitat variables in Crow Creek within F.E. Warren Air Force Base, Laramie County, Wyoming. Water velocity and longitudinal location showed the highest numbers of significant correlations with abundance of macroinvertebrate taxa. Changes in the macroinvertebrate community with changes in longitudinal location appeared to result from increasing urbanization with downstream movement. Caenis lattipennis , Ceratopogonidae, and Dubiraphia sp. were rare in the downstream portion of the study reach that has received substantial human disturbance.

Journal of Freshwater Ecology↗

USGS2015

Broad-scale assessments of ecological landscapes: developing methods and applications

The U.S. Department of the Interior (DOI) Bureau of Land Management (BLM) is developing a Landscape Approach for managing multiple uses of public lands by incorporating multiscale information to quantify the effects of natural and human influences on natural resource conditions and trends. A primary goal of the approach is to identify opportunities for resource conservation, restoration, and development. The BLM Landscape Approach is developing assessment methods that promote consistency in management decisions, identify ecological characteristics that promote ecosystem resilience under rapidly changing environmental conditions, and foster collaboration among land management agencies. The BLM Landscape Approach is closely aligned with the DOI’s “A Strategy for Improving the Mitigation Policies and Practices of The Department of the Interior.” A major component of the BLM Landscape Approach is the Rapid Ecoregional Assessment (REA) program. REAs identify important ecosystems and wildlife habitats at broad spatial scales and determine where these resources are at risk from environmental stressors that can affect the integrity of ecological systems. Building on the lessons learned from completed or current REAs, the BLM, in partnership with the U.S. Geological Survey, will perform systematic comparisons of REA methods to identify the most promising suite of landscape-level analysis tools. In addition, the BLM and USGS will develop practical applications that demonstrate how to incorporate assessment information to address existing management issues, such as cumulative effects of proposed management actions. The outcome of these efforts will be a set of comprehensive technical guidance documents for conducting and applying broad-scale assessments.

Fact Sheet↗

USGS2017

Using regional scale flow–ecology modeling to identify catchments where fish assemblages are most vulnerable to changes in water availability

Streamflow is essential for maintaining healthy aquatic ecosystems and for supporting human water supply needs. Changes in climate, land use and water use practices may alter water availability. Understanding the potential effect of these changes on aquatic ecosystems is critical for long-term water management to maintain a balance between water for human consumption and ecosystem needs. Fish species data and streamflow estimates from a rainfall-runoff and flow routing model were used to develop boosted regression tree models to predict the relationship between streamflow and fish species richness (FSR) under plausible scenarios of (1) water withdrawal, (2) climate change and (3) increases in impervious surfaces in the Piedmont ecoregion of North Carolina, U.S.A. Maximum monthly flow, the fraction of total flow originating from impervious surface runoff, coefficient of monthly streamflow variability, and the specific river basin accounted for 50% of the variability in FSR. This model was used to predict FSR values for all twelve-digit Hydrological Unit Code catchments (HUC-12s) in the North Carolina Piedmont under current flow conditions and under water withdrawal, climate change and impervious surface scenarios. Flow–ecology modeling results indicate that predicted FSR declined significantly with increased water withdrawals. However, the magnitude of decline varied geographically. A “hot-spot” analysis was conducted based on predicted changes in FSR under each scenario to understand which HUC-12s were most likely to be affected by changes in water withdrawals, climate and impervious surfaces. Under the 20% withdrawal increase scenario, 413 of 886 (47%) HUC-12s in the study area were predicted to lose one or more species. HUC-12s in the Broad, Catawba, Yadkin and Cape Fear river basins were most susceptible to species loss. These findings may help decision making efforts by identifying catchments most vulnerable to changing water availability. Additionally, FSR-discharge modeling results can assist resource agencies, water managers and stakeholders in assessing the effect of water withdrawals in catchments to better support the protection and long-term conservation of species.

North Carolina↗

USGS2020

Resist-accept-direct (RAD)-A framework for the 21st-century natural resource manager

An assumption of stationarity—i.e. “the idea that natural systems fluctuate within an unchanging envelope of variability” (Milly et al. 2008)—underlies traditional conservation and natural resource management, as evidenced by widespread reliance on ecological baselines to guide protection, restoration, and other management. Although ecological change certainly occurred under the relatively stable conditions of the recent past, the nature of change under intensifying global change is different; it is unidirectional, and rapidly pushing beyond the bounds of historical variability. In the past, a manager could plausibly work to reverse or mitigate many stressors or their impacts to approximate pre-disturbance ecological conditions, but now accelerated warming, changing disturbance regimes, and extreme events associated with climate change reduce that potential. Indeed, even ‘holding the line’ in the face of inexorable human-caused change is ever more difficult and costly. Thus, the convention of using baseline conditions to define goals for today’s resource management is increasingly untenable, presenting practical and philosophical challenges for managers. As formerly familiar ecological conditions continue to change, bringing novelty, surprise, and uncertainty, natural resource managers require a new, shared approach to make conservation decisions. How, for example, should a manager respond to projections of loss of the Joshua tree from much of its current range, or to the emergence of new and different vegetation communities after a large fire event? The RAD (Resist-Accept-Direct) decision framework has emerged over the past decade as a simple tool that captures the entire decision space for responding to ecosystems facing the potential for rapid, irreversible ecological change. It assists managers in making informed, purposeful choices about how to respond to the trajectory of change, and moreover, provides a straightforward approach to support resource managers in collaborating at larger scales across jurisdictions, which today is more urgent than ever.

Natural Resource Report↗

USGS2011

Portrait of a small population of boreal toads ( Anaxyrus boreas )

Much attention has been given to the conservation of small populations, those that are small because of decline, and those that are naturally small. Small populations are of particular interest because ecological theory suggests that they are vulnerable to the deleterious effects of environmental, demographic, and genetic stochasticity as well as natural and human-induced catastrophes. However, testing theory and developing applicable conservation measures for small populations is hampered by sparse data. This lack of information is frequently driven by computational issues with small data sets that can be confounded by the impacts of stressors. We present estimates of demographic parameters from a small population of Boreal Toads (Anaxyrus boreas) that has been surveyed since 2001 by using capture-recapture methods. Estimates of annual adult survival probability are high relative to other Boreal Toad populations, whereas estimates of recruitment rate are low. Despite using simple models, clear patterns emerged from the analyses, suggesting that population size is constrained by low recruitment of adults and is declining slowly. These patterns provide insights that are useful in developing management directions for this small population, and this study serves as an example of the potential for small populations to yield robust and useful information despite sample size constraints.

Herpetologica↗