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USGS2025

Density as a mechanism linking habitat disturbance to increased pathogen prevalence: Evidence from a natural experiment

Sudden habitat loss associated with environmental disturbance can trigger animals to move from affected to undisturbed areas, where increases in local density may occur. Although pathogen transmission is strongly related to local density, how crowding after habitat loss affects infection dynamics in wild populations remains unclear. Here we conceptualize the Disturbance-Density-Disease hypothesis, which posits that disturbance-induced habitat loss results in increased pathogen prevalence via increases in local density at adjacent, undisturbed patches. We then used data from before, during, and after flooding disturbance to test this hypothesis in boreal toads Anaxyrus boreas boreas co-occurring with the pathogenic fungus Batrachochytrium dendrobatidis ( Bd ). We collected Bd samples from captured individuals during a 5-year (2015–2019) mark-recapture study of boreal toads ( n = 1295) that breed in beaver ponds in western Wyoming, USA. During spring of 2017, an extreme flooding event destroyed several beaver dams, resulting in the loss of breeding habitat. We compared host density and pathogen prevalence pre- and post-disturbance at sites affected versus unaffected by flooding. At affected sites, population density and Bd prevalence increased at adjacent, undisturbed ponds following the sudden loss of habitat. Moreover, neither host density nor Bd prevalence increased at control sites in areas unaffected by flooding. Taken together, our results support hypothesized links between disturbance, adjacent increases in density, and subsequent increases in pathogen prevalence. Our study contributes to a growing body of ecological research leveraging natural experiments to extract insights from extreme disturbance events. By doing so, we demonstrate an important consequence of disturbance beyond proximate habitat loss and introduce a clear conceptual approach (the Disturbance-Density-Disease hypothesis) to understanding how pathogen transmission can be affected by disturbance via alterations to local density.

Wyoming↗

USGS1997

Industrially induced changes in Earth structure at the geysers geothermal area, California

Industrial exploitation is causing clearly-measurable changes in Earth structure at The Geysers geothermal area, California. Production at The Geysers peaked in the late 1980s at ∼3.5 × 10³ kg s −1 of steam and 1800 MW of electricity. It subsequently decreased by about 10% per year [ Barker et al. , 1992] because of declining reservoir pressure. The steam reservoir coincides with a strong negative anomaly (∼0.16, ∼9%) in the compressional-to-shear seismic wave speed ratio V P / V S , consistent with the expected effects of low-pressure vapor-phase pore fluid [ Julian et al. , 1996]. Between 1991 and 1994 this anomaly increased in amplitude by up to about 0.07 (∼4%). This is consistent with the expected effects of continued pressure reduction and conversion of pore water to steam as a result of exploitation. These unique results show that V P / V S tomography can easily detect saturation changes caused by exploitation of reservoirs, and is a potentially valuable technique for monitoring environmental change. They also provide geophysical observational evidence that geothermal energy is not a renewable energy source.

Geophysical Research Letters↗

USGS2002

The endemic headwater stream amphibians of the American Northwest: Associations with environmental gradients in a large forested preserve

We used a large forested preserve (Olympic National Park, USA) to examine the habitat associations of a unique and environmentally sensitive stream amphibian fauna: Ascaphus truei Stegneger, Rhyacotriton olympicus (Gaige) and Dicamptodon copei Nussbaum. We quantified the relative abundance of stream amphibians and compared them to physical, topographic, climatic and landscape variables. All three species were associated with the south-west to north-east climate gradient, tending to be most abundant in the south-west. Although a habitat generalist relative to the other two species, Dicamptodon copei was absent from the north-eastern portion of the park. Ascaphus truei and Rhyacotriton olympicus were both associated with coarse substrates and steep gradients. Unlike studies in harvested forests, all stream amphibians were common in waters with unconsolidated surface geology (e.g. marine sediments that erode easily). Studies of ecological preserves can provide an important baseline for evaluating species associations with environmental gradients and can reveal patterns not evident in more disturbed landscapes.

Global Ecology and Biogeography↗

USGS2012

Effects of urban development on stream ecosystems in nine metropolitan study areas across the United States

Urban development is an important agent of environmental change in the United States. The urban footprint on the American landscape has expanded during a century and a half of almost continuous development. Eighty percent of Americans now live in metropolitan areas, and the advantages and challenges of living in these developed areas—convenience, congestion, employment, pollution—are part of the day-to-day realities of most Americans. Nowhere are the environmental changes associated with urban development more evident than in urban streams. Contaminants, habitat destruction, and increasing streamflow flashiness resulting from urban development have been associated with the disruption of biological communities, particularly the loss of sensitive aquatic species. Every stream is connected downstream to larger water bodies, including rivers, reservoirs, and ultimately coastal waters. Inputs of chemical contaminants or sediments at any point along the stream can cause degradation downstream with adverse effects on biological communities and on economically valuable resources, such as fisheries and tourism. In response to general concerns about the degradation of urban streams, the U.S. Geological Survey (USGS) conducted a national-scale, scientific investigation of the effects of urban development on stream ecosystems. Nine metropolitan study areas of the United States were selected—Portland, Oregon; Salt Lake City, Utah; Birmingham, Alabama; Atlanta, Georgia; Raleigh, North Carolina; Boston, Massachusetts; Denver, Colorado; Dallas, Texas; and Milwaukee, Wisconsin. The studies were conducted in Salt Lake City, Birmingham, and Boston in 1999–2000; in Atlanta, Raleigh, and Denver in 2002–2003; and in Portland, Dallas, and Milwaukee in 2003–2004. The comprehensive investigation of all nine studies focused on three broad questions of interest to decision makers: What are the primary effects of urban development on stream ecosystems? How do the effects of urban development on stream ecosystems vary regionally across the country? Which urban-related stressors are most closely linked to biological community degradation, and how can multiple stressors be managed to protect stream health as a watershed becomes increasingly urbanized?

Alabama;Colorado;Georgia;Massachusetts;North Carol↗

USGS2012

Strategies for managing the effects of urban development on streams

Urban development remains an important agent of environmental change in the United States. The U.S. population grew by 17 percent from 1982 to 1997, while urbanized land area grew by 47 percent, suggesting that urban land consumption far outpaced population growth (Fulton and others, 2001; Sierra Club, 2003; American Farmland Trust, 2009). Eighty percent of Americans now live in metropolitan areas. Each American effectively occupies about 20 percent more developed land (for housing, schools, shopping, roads, and other related services) than 20 years ago (Markham and Steinzor, 2006). Passel and Cohn (2008) predict a dramatic 48 percent increase in the population of the United States from 2005 to 2050. The advantages and challenges of living in these developed areas—convenience, congestion, employment, pollution—are part of the day-to-day realities of most Americans. Nowhere are the environmental changes associated with urban development more evident than in urban streams. The U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program investigation of the effects of urban development on stream ecosystems (EUSE) during 1999–2004 provides the most spatially comprehensive analysis of stream impacts of urban development that has been completed in the United States. A nationally consistent study design was used in nine metropolitan areas of the United States—Portland, Oregon; Salt Lake City, Utah; Birmingham, Alabama; Atlanta, Georgia; Raleigh, North Carolina; Boston, Massachusetts; Denver, Colorado; Dallas, Texas; and Milwaukee, Wisconsin. A summary report published as part of the EUSE study describes several of these impacts on urban streams ( Coles and others, 2012 ).

Alabama;Colorado;Georgia;Massachusetts;North Carol↗

USGS2012

Urban development results in stressors that degrade stream ecosystems

In 2003, eighty-three percent of Americans lived in metropolitan areas, and considerable population increases are predicted within the next 50 years. Nowhere are the environmental changes associated with urban development more evident than in urban streams. Contaminants, habitat destruction, and increasing streamflow flashiness resulting from urban development have been associated with the disruption of biological communities, particularly the loss of sensitive aquatic biota. Every stream is connected downstream to other water bodies, and inputs of contaminants and (or) sediments to streams can cause degradation downstream with adverse effects on biological communities and on economically valuable resources, such as fisheries and tourism. Understanding how algal, invertebrate, and fish communities respond to physical and chemical stressors associated with urban development can provide important clues on how multiple stressors may be managed to protect stream health as a watershed becomes increasingly urbanized. This fact sheet highlights selected findings of a comprehensive assessment by the National Water-Quality Assessment Program of the U.S. Geological Survey (USGS) of the effects of urban development on stream ecosystems in nine metropolitan study areas.

Fact Sheet↗

USGS1996

Distribution of petroleum hydrocarbons and toluene biodegradation, Knox Street fire pits, Fort Bragg, North Carolina

An investigation was conducted at the Knox Street fire pits, Fort Bragg, North Carolina, to monitor the distribution of toluene, ethylbenzene, and xylene (TEX) in soil vapor, ground water, and ground-water/vapor to evaluate if total concentrations of TEX at the site are decreasing with time, and to quantify biodegradation rates of toluene in the unsaturated and saturated zones. Soil-vapor and ground-water samples were collected around the fire pits and ground-water/vapor samples were collected along the ground-water discharge zone, Beaver Creek, on a monthly basis from June 1994 through June 1995. Concentrations of TEX compounds in these samples were determined with a field gas chro- matograph. Laboratory experiments were performed on aquifer sediment samples to measure rates of toluene biodegradation by in situ micro- organisms. Based on field gas chromatographic analytical results, contamination levels of TEX compounds in both soil vapor and ground water appear to decrease downgradient of the fire-pit source area. During the 1-year study period, the observed temporal and spatial trends in soil vapor TEX concentrations appear to reflect differences in the distribution of TEX among solid, aqueous, and gaseous phases within fuel-contaminated soils in the unsaturated zone. Soil temperature and soil moisture are two important factors which influence the distribution of TEX com- pounds among the different phases. Because of the short period of data collection, it was not possible to distinguish between seasonal fluc- tuations in soil vapor TEX concentrations and an overall net decrease in TEX concentrations at the study site. No seasonal trend was observed in total TEX concentrations for ground- water samples collected at the study site. Although the analytical results could not be used to determine if ground-water TEX concen- trations decreased during the study at a specific location, the data were used to examine rate constants of toluene biodegradation. Based on ground-water toluene concentration data, a maximum rate constant for anaerobic biodegradation of toluene in the saturated zone was estimated to be as low as 0.002 d-1 or as high as 0.026 d-1. Based on analyses of ground-water/vapor samples, toluene was the prin- cipal TEX compound identified in ground water discharging to Beaver Creek. Observed decreases in ground-water/vapor toluene concentrations during the study period may reflect a decrease in source inputs, an increase in dilution caused by higher ground-water flow, and(or) removal by biological or other physical processes. Rate constants of toluene anaerobic biodegradation determined by laboratory measurements illustrate a typical acclimation response of micro-organisms to hydrocarbon contamination in sediments collected from the site. Toluene biodegradation rate constants derived from laboratory microcosm studies ranged from 0.001 to 0.027 d-1, which is similar to the range of 0.002 to 0.026 d-1 for toluene biodegradation rate constants derived from ground-water analytical data. The close agreement of toluene biodegradation rate constants reported using both approaches offer strong evidence that toluene can be degraded at environmentally significant rates at the study site.

Water-Resources Investigations Report↗

USGS2006

Birds and polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAH) are present throughout the global environment and are produced naturally and by activities of humans. Effects of PAH on birds have been determined by studies employing egg injection, egg immersion, egg shell application, single and multiple oral doses, subcutaneous injection, and chemical analysis of field-collected eggs and tissue. The four-to six-ring aromatic compounds are the most toxic to embryos, young birds, and adult birds. For embryos, effects include death, developmental abnormalities, and a variety of cellular and biochemical responses. For adult and young birds, effects include reduced egg production and hatching, increased clutch or brood abandonment, reduced growth, increased organweights, and a variety of biochemical responses. Trophic level accumulation is unlikely. Environmental exposure to PAH in areas of high human population or habitats affected by recent petroleum spills might be sufficient to adversely affect reproduction. Evidence of long-term effects of elevated concentrations of environmental PAH on bird populations is very limited and the mechanisms of effect are unclear.

Avian and Poultry Biology Reviews↗

USGS2025

Cryptic CAM photosynthesis in Joshua tree (Yucca brevifolia, Y. jaegeriana)

Joshua trees are long-lived perennial monocots native to the Mojave Desert in North America. Composed of two species, Yucca brevifolia and Y. jaegeriana (Asparagaceae), Joshua trees are imperiled by climate change, with decreases in suitable habitat predicted under future climate change scenarios. Relatively little is understood about the ecophysiology of Joshua trees across their range, including the extent to which populations are locally adapted or phenotypically plastic to environmental stress. Plants in our common gardens showed evidence of Crassulacean acid metabolism photosynthesis (CAM) in a pilot experiment, despite no prior report of this photosynthetic pathway in these species. We further studied the variation and strength of CAM within a single common garden, measuring seedlings representing populations across the range of the two species. A combination of physiology and transcriptomic data showed low levels of CAM that varied across populations but were unrelated to home environmental conditions. Gene expression confirmed CAM activity and further suggested differences in carbon and nitrogen metabolism between Y. brevifolia and Y. jaegeriana. Together the results suggest greater physiological diversity between these species than initially expected, particularly at the seedling stage, with implications for future survival of Joshua trees under a warming climate.

New Phytologist↗

USGS2003

Late Eocene impacts: Geologic record, correlation, and paleoenvironmental consequences

We present new magnetostratigraphic and stable isotopic ( 𝜹 18 C, 𝜹 13 C carb ) data to help improve correlations among three late Eocene impact craters and their inferred breccia and ejecta deposits. Our analyses also shed light on potential global environmental consequences attributable to the impacts. The new data come from a continuously cored interval of the subsurface Chickahominy Formation, which lies conformably above the Chesapeake Bay impact crater in southeastern Virginia. The new magnetostratigraphic data indicate that the Chesapeake Bay impact took place in Chron C16n. 2n, the same magnetochron that encompasses the late Eocene ejecta layer at Massignano, Italy. This correlation places both the Chesapeake Bay impact and the Massignano ejecta at ~35.6 Ma, and resolves a previous miscorrelation between these two sites based on planktonic foraminifera and calcareous nannofossils. The new magnetostratigraphic correlations also suggest that the published magnetostratigraphic framework for ejecta-bearing late Eocene strata ar ODP Site 689B (Maud Rise) is incorrect, due to an incomplete section. New 𝜹 18 C data (single species of benthic foraminifera) from the same Chickahominy section ar Chesapeake Bay indicate that successional intervals of warm oceanic bottom-water may be characteristic of the late Eocene. We infer that the warm intervals correlate with successive episodes of greenhouse warming, triggered in part by a comer shower, which produced the Chesapeake Bay, Toms Canyon, Popigai, and presumably additional (as yet undiscovered) late Eocene impact craters. We also demonstrate that a marked negative execution of 𝜹 13 C carb persists through the upper half of the Chickahominy Formation. This excursion, also recorded at Massigno, at Bath Cliff, Barbados, and at other widespread localities in the world ocean, may be additional evidence of global-scale, long-term environmental disturbances related to the bolide impacts. As such, this 𝜹 13 C signal may be useful for global subdivision of the late Eocene stratigraphic record.

Book chapter↗

USGS2016

Evaluating within-population variability in behavior and demography for the adaptive potential of a dispersal-limited species to climate change

Multiple pathways exist for species to respond to changing climates. However, responses of dispersal-limited species will be more strongly tied to ability to adapt within existing populations as rates of environmental change will likely exceed movement rates. Here, we assess adaptive capacity in Plethodon cinereus , a dispersal-limited woodland salamander. We quantify plasticity in behavior and variation in demography to observed variation in environmental variables over a 5-year period. We found strong evidence that temperature and rainfall influence P. cinereus surface presence, indicating changes in climate are likely to affect seasonal activity patterns. We also found that warmer summer temperatures reduced individual growth rates into the autumn, which is likely to have negative demographic consequences. Reduced growth rates may delay reproductive maturity and lead to reductions in size-specific fecundity, potentially reducing population-level persistence. To better understand within-population variability in responses, we examined differences between two common color morphs. Previous evidence suggests that the color polymorphism may be linked to physiological differences in heat and moisture tolerance. We found only moderate support for morph-specific differences for the relationship between individual growth and temperature. Measuring environmental sensitivity to climatic variability is the first step in predicting species' responses to climate change. Our results suggest phenological shifts and changes in growth rates are likely responses under scenarios where further warming occurs, and we discuss possible adaptive strategies for resulting selective pressures.

Ecology and Evolution↗

USGS2025

Understanding and predicting infection dynamics for an endangered amphibian using long-term surveys of wild and translocated frogs

Amphibians are a prominent component of Earth's sixth mass extinction and the fungal pathogen Batrachochytrium dendrobatidis (Bd) is a primary driver of declines. Although Bd dynamics are well studied, the environmental drivers, exacerbating risk factors, and value of conservation interventions like translocations remain challenging to predict. Here, we present results from two decades of Bd monitoring for mountain yellow-legged frogs ( Rana muscosa) in the southern California Transverse and Peninsular mountain ranges. We describe Bd prevalence and infection intensity across sites; model how variables associated with climate, habitat, and populations relate to prevalence; and integrate Bd data from wild and translocated frogs to test whether a machine learning system can predict infection prevalence at new sites. Our findings indicate substantial spatiotemporal variation in Bd dynamics. Bd was present at all sites but prevalence and infection intensities were often low. Environmental features including temperature, precipitation, vegetation, and shortwave radiation explained significant variation in Bd prevalence, but their predictive value varied across mountain ranges. Although clear environmental predictors across populations remain elusive, we provide evidence for the importance of warmer and wetter springs and winters, with implications of increased risk under climate change predictions. We also found evidence for higher Bd prevalence among translocated than wild frogs. Although our machine learning model predicted a Bd prevalence threshold with relatively high accuracy, understanding the factors driving within- and between-population Bd dynamics is complex. Taken together, our findings provide new insights into the complicated role of Bd in amphibian declines and suggest revised management approaches.

California↗

USGS2019

Review of and recommendations for monitoring contaminants and their effects in the San Francisco Bay−Delta

Legacy and current-use contaminants enter into and accumulate throughout the San Francisco Bay−Delta (Bay−Delta), and are present at concentrations with known effects on species important to this diverse watershed. There remains major uncertainty and a lack of focused research able to address and provide understanding of effects across multiple biological scales, despite previous and ongoing emphasis on the need for it. These needs are challenging specifically because of the established regulatory programs that often monitor on a chemical- by-chemical basis, or in which decisions are grounded in lethality-based endpoints. To best address issues of contaminants in the Bay−Delta, monitoring efforts should consider effects of environmentally relevant mixtures and sub- lethal impacts that can affect ecosystem health. These efforts need to consider the complex environment in the Bay−Delta including variable abiotic (e.g., temperature, salinity) and biotic (e.g., pathogens) factors. This calls for controlled and focused research, and the development of a multi-disciplinary contaminant monitoring and assessment program that provides information across biological scales. Information gained in this manner will contribute toward evaluating parameters that could alleviate ecologically detrimental outcomes. This review is a result of a Special Symposium convened at the University of California−Davis (UCD) on January 31, 2017 to address critical information needed on how contaminants affect the Bay−Delta. The UCD Symposium focused on new tools and approaches for assessing multiple stressor effects to freshwater and estuarine systems. Our approach is similar to the recently proposed framework laid out by the U.S. Environmental Protection Agency (USEPA) that uses weight of evidence to scale toxicological responses to chemical contaminants in a laboratory, and to guide the conservation of priority species and habitats. As such, we also aimed to recommend multiple endpoints that could be used to promote a multi-disciplinary understanding of contaminant risks in Bay−Delta while supporting management needs.

California↗

USGS2011

A trait-based framework for predicting when and where microbial adaptation to climate change will affect ecosystem functioning

As the earth system changes in response to human activities, a critical objective is to predict how biogeochemical process rates (e.g. nitrification, decomposition) and ecosystem function (e.g. net ecosystem productivity) will change under future conditions. A particular challenge is that the microbial communities that drive many of these processes are capable of adapting to environmental change in ways that alter ecosystem functioning. Despite evidence that microbes can adapt to temperature, precipitation regimes, and redox fluctuations, microbial communities are typically not optimally adapted to their local environment. For example, temperature optima for growth and enzyme activity are often greater than in situ temperatures in their environment. Here we discuss fundamental constraints on microbial adaptation and suggest specific environments where microbial adaptation to climate change (or lack thereof) is most likely to alter ecosystem functioning. Our framework is based on two principal assumptions. First, there are fundamental ecological trade-offs in microbial community traits that occur across environmental gradients (in time and space). These trade-offs result in shifting of microbial function (e.g. ability to take up resources at low temperature) in response to adaptation of another trait (e.g. limiting maintenance respiration at high temperature). Second, the mechanism and level of microbial community adaptation to changing environmental parameters is a function of the potential rate of change in community composition relative to the rate of environmental change. Together, this framework provides a basis for developing testable predictions about how the rate and degree of microbial adaptation to climate change will alter biogeochemical processes in aquatic and terrestrial ecosystems across the planet.

Biogeochemistry↗

USGS2022

A forested wetland at a climate-induced tipping-point: 17-year demographic evidence of widespread tree recruitment failure

Regeneration and survival of forested wetlands are affected by environmental variables related to the hydrologic regime. Climate change, specifically alterations to precipitation patterns, may have outsized effects on these forests. In Tennessee, USA, precipitation has increased by 15% since 1960. The goal of our research was to assess the evidence for whether this change in precipitation patterns resulted in shorter growing seasons and recruitment failure in common canopy trees for a forest wetland. In 2001 and 2018, the density of Quercus lyrata (overcup oak), Liquidambar styraciflua (sweetgum), Quercus phellos (willow oak), and Betula nigra (river birch) seedling, sapling and adult density were mapped in an area of 2.3 ha within a seasonally flooded karst depression. Overall, the percentage of the growing season experiencing inundation was 26% greater in the deep than in shallow areas between 2001 and 2018. Saplings and small adults of all four species were restricted to shallow areas, and their abundance has declined substantially. Overcup oak and sweetgum individuals that were recruited into the adult life history stage were repelled from the deep zone. Overcup oak and sweetgum adults experienced lower mortality across the 2.3-ha study area (11% and 26%, respectively) relative to willow oak (56%) and river birch (64%) over the 17-year study. Growing-season inundation showed no relation to mortality in adult sweetgum and willow oak, a positive relation to mortality among adult river birch across size classes and among small adult overcup oak, and an inverse relation to mortality among large adult overcup oak. In shallow regions, overcup oak and sweetgum adults had greater basal area increment relative to the intermediate and deep regions of the pond. Results of hydrologic modeling for the study area, based on rainfall and temperature records covering 1855–2019, show ponding durations after 1970 considerably longer than the historical baseline, across ponding-depth classes. Our results strongly suggest that climate change is a driving factor suppressing tree regeneration since 1970 in this seasonally flooded karst depression.

Tennessee↗

USGS2020

Photosynthetic and respiratory acclimation of understory shrubs in response to in situ experimental warming of a wet tropical forest

Despite the importance of tropical forests to global carbon balance, our understanding of how tropical plant physiology will respond to climate warming is limited. In addition, the contribution of tropical forest understories to global carbon cycling is predicted to increase with rising temperatures, however, in situ warming studies of tropical forest plants to date focus only on upper canopies. We present results of an in situ field-scale +4°C understory infrared warming experiment in Puerto Rico (Tropical Responses to Altered Climate Experiment; TRACE). We investigated gas exchange responses of two common understory shrubs, Psychotria brachiata and Piper glabrescens , after exposure to 4 and 8 months warming. We assessed physiological acclimation in two ways: (1) by comparing plot-level physiological responses in heated versus control treatments before and after warming, and (2) by examining physiological responses of individual plants to variation in environmental drivers across all plots, seasons, and treatments. P. brachiata has the capacity to up-regulate (i.e., acclimate) photosynthesis through broadened thermal niche and up-regulation of photosynthetic temperature optimum ( T opt ) with warmer temperatures. P. glabrescens , however, did not upregulate any photosynthetic parameter, but rather experienced declines in the rate of photosynthesis at the optimum temperature ( A opt ), corresponding with lower stomatal conductance under warmer daily temperatures. Contrary to expectation, neither species showed strong evidence for respiratory acclimation. P. brachiata down-regulated basal respiration with warmer daily temperatures during the drier winter months only. P. glabrescens showed no evidence of respiratory acclimation. Unexpectedly, soil moisture, was the strongest environmental driver of daily physiological temperature responses, not vegetation temperature. T opt increased, while photosynthesis and basal respiration declined as soils dried, suggesting that drier conditions negatively affected carbon uptake for both species. Overall, P. brachiata , an early successional shrub, showed higher acclimation potential to daily temperature variations, potentially mitigating negative effects of chronic warming. The negative photosynthetic response to warming experienced by P. glabrescens , a mid-successional shrub, suggests that this species may not be able to as successfully tolerate future, warmer temperatures. These results highlight the importance of considering species when assessing climate change and relay the importance of soil moisture on plant function in large-scale warming experiments.

Puerto Rico↗

USGS1990

Dicofol (Kelthane) as an environmental contaminant: A review

Dicofol is persistent in soil and on plants. No compelling evidence exists that dicofol breaks down or is metabolized to DDTr in nature. Dicofol does not accumulate in birds as rapidly as DDE, and it has reproductive effects that are less harmful than DDE. Fish, birds, and mammals are reproductively sensitive to dicofol products, but levels presently found in wildlife are below levels shown experimentally to cause significant harm. Eggs of fish-eating wild birds from citrus, cotton, and apple-growing areas should be analyzed for dicofol residues. Nest success of fish-eating birds in the most contaminated populations should be studied to evaluate the environmental effects of dicofol.

Fish and Wildlife Technical Report↗

USGS2025

Climate consideration in environmental effects analyses on federal public lands in the United States

Effects of a changing climate, including drought, wildfire, and invasive species encroachment, are evident on public lands across the United States. Decision making on Federal public lands requires analyses under the National Environmental Policy Act (NEPA), and there are guidelines for considering climate in NEPA analyses. To better understand how climate most recently has been considered, we analyzed a stratified random sample of 130 environmental assessments (EAs) completed by the Bureau of Land Management (BLM) from 2021 to 2023 across the contiguous United States. We assessed whether EAs considered (1) potential effects of the proposed action on climate (2) potential climate effects on the proposed action, and (3) potential climate effects on resources of concern. We also identified whether EAs included data and science about climate or greenhouse gas emissions, and which datasets and documents were cited. We used two approaches: automated keyword searches and document analysis. Thirty-seven percent of EAs considered the potential effects of the proposed action on climate, 8% considered the potential effects of climate on the proposed action, and 4% of individual resource analyses considered the potential effects of climate on the resource. EAs in the ‘oil and gas development,’ ‘renewable energy,’ and ‘forestry and timber management’ proposed action categories most frequently considered the potential effects of climate and used climate data and science. Our findings suggest an opportunity for scientists to work more closely with public land managers to identify available data and science for considering climate in environmental effects analyses and to provide science delivery mechanisms that can facilitate the consideration and use of climate science in decision making.

Environmental Management↗