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Results for “Environmental Monitoring and Assessment”

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At least 289 records · Page 16Linked to original sources
USGS2004

Michigan lakes: An assessment of water quality

Michigan has more than 11,000 inland lakes, that provide countless recreational opportunities and are an important resource that makes tourism and recreation a $15-billion-dollar per-year industry in the State (Stynes, 2002). Knowledge of the water-quality characteristics of inland lakes is essential for the current and future management of these resources. Historically the U. S. Geological Survey (USGS) and the Michigan Department of Environmental Quality (MDEQ) jointly have monitored water quality in Michigan's lakes and rivers. During the 1990's, however, funding for surface-water-quality monitoring was reduced greatly. In 1998, the citizens of Michigan passed the Clean Michigan Initiative to clean up, protect, and enhance Michigan's environmental infrastructure. Because of expanding water-quality-data needs, the MDEQ and the USGS jointly redesigned and implemented the Lake Water-Quality Assessment (LWQA) Monitoring Program (Michigan Department of Environmental Quality, 1997).

Michigan↗
USGS2025

Retrospective stepwise prioritization of chemicals detected in Great Lakes tributaries (2008–2018)

Through the U.S. Great Lakes Restoration Initiative, a 10-year, multiagency chemical monitoring effort was undertaken across the Great Lakes. In this effort, 586 chemicals were monitored and 334 were detected in grab/composite water samples. To help inform potential future actions, a stepwise prioritization framework was used to identify compounds for which publicly accessible water quality guidelines or effects information suggested there was potential aquatic ecotoxicity. Because water quality guidelines were only available for some chemicals, this framework used apical toxicity data collated from publicly accessible databases (e.g., the ECOTOXicology Knowledgebase) and alternative data, including literature-derived non-apical effect concentrations, in vitro bioactivities from high-throughput screening, and modeled ecotoxicity. To account for the diverse levels of confidence in these data, chemicals were prioritized within specific action categories, which suggested potential management or experimental activities that may be considered based on the types of data available for each compound. Overall, 11 detected chemicals were identified as high priority in different action categories. This included four chemicals prioritized for environmental management or targeted risk assessment, three chemicals prioritized for effects-based monitoring, one chemical prioritized for apical effects assessment, and three chemicals targeted for non-apical effects evaluation. This framework also identified 164 low-priority chemicals, among which more than 50% were prioritized based on water quality guidelines or apical effect concentrations (thus could be considered low priority for future risk assessment or management activities). Results aim to help regulatory agencies, environmental managers, and other stakeholders focus available resources on carrying out monitoring, experimental, and risk assessments for the chemicals that display the greatest potential to adversely impact Great Lakes ecosystems.

Great Lakes↗
USGS2026

Seasonal drivers of density in a subarctic population of northern red-backed voles

Northern red-backed voles ( Clethrionomys rutilus ) are an important species in the boreal forest ecosystem, both as herbivores and as a key food source for many mammalian and avian predators. They exhibit dramatic inter- and intra-annual population fluctuations, for which causes are not entirely known. We monitored northern red-backed vole densities in Denali National Park and Preserve through time with the goal of examining how environmental factors influenced density over time. Using a 30-year record of mark-recapture data, we used spatially explicit capture-recapture methods to estimate autumn and early summer densities each year. We assessed cyclic patterns in density, variation in amplitude, and any periodicity of population fluctuations using post hoc linear modeling. We found that the vole population appeared to be cyclic with a 2–4 year period, although the pattern varied somewhat among sampling sites. Our results indicated an association between white spruce ( Picea glauca ) seed production and vole density, implying white spruce seeds were either an important source of food during winter seasons, or that the environmental triggers that promote high seed fall were also associated with increased vole density. We also found a negative effect of an autumn harshness index, indicating winter conditions play a role in vole density in the following season. Finally, we found evidence of a negative density-dependent relationship between autumn and early summer. Together, these findings suggest a system in which density dependence and cyclic relationships are irregular but highly influential, with environmental effects capable of enhancing or moderating their impact. Continued monitoring of voles, alongside more thorough assessments of environmental conditions, may provide additional insight into the complex population dynamics of this species.

Alaska↗
USGS2024

Evaluating the reliability of environmental concentration data to characterize exposure in environmental risk assessments

Environmental risk assessments often rely on measured concentrations in environmental matrices to characterize exposure of the population of interest—typically, humans, aquatic biota, or other wildlife. Yet, there is limited guidance available on how to report and evaluate exposure datasets for reliability and relevance, despite their importance to regulatory decision-making. This paper is the second of a four-paper series detailing the outcomes of a Society of Environmental Toxicology and Chemistry Technical Workshop that has developed Criteria for Reporting and Evaluating Exposure Datasets (CREED). It presents specific criteria to systematically evaluate the reliability of environmental exposure datasets. These criteria can help risk assessors understand and characterize uncertainties when existing data are used in various types of assessments and can serve as guidance on best practice for the reporting of data for data generators (to maximize utility of their datasets). Although most reliability criteria are universal, some practices may need to be evaluated considering the purpose of the assessment. Reliability refers to the inherent quality of the dataset and evaluation criteria address the identification of analytes, study sites, environmental matrices, sampling dates, sample collection methods, analytical method performance, data handling or aggregation, treatment of censored data, and generation of summary statistics. Each criterion is evaluated as “fully met,” “partly met,” “not met or inappropriate,” “not reported,” or “not applicable” for the dataset being reviewed. The evaluation concludes with a scheme for scoring the dataset as reliable with or without restrictions, not reliable, or not assignable, and is demonstrated with three case studies representing both organic and inorganic constituents, and different study designs and assessment purposes. Reliability evaluation can be used in conjunction with relevance evaluation (assessed separately) to determine the extent to which environmental monitoring datasets are “fit for purpose,” that is, suitable for use in various types of assessments. Integr Environ Assess Manag 2024;00:1–23. © 2024 Society of Environmental Toxicology & Chemistry (SETAC). This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Integrated Environmental Assessment and Management↗
USGS2024

Environmental drivers and spatial patterns of antibiotic-resistant, enteric coliforms across a forest–urban riverscape

Antibiotic resistant bacteria are prevalent environmental contaminants in freshwaters, and antibiotic resistance genes circulate throughout the urban water cycle. The increase of antibiotic resistant pathogens threatens public health through direct and indirect exposure, and natural resource managers need information on the spatial patterns of antibiotic resistant bacteria and environmental factors associated with their distribution to improve water quality monitoring and to better assess human, animal, and environmental health risks. We collected water and epilithic biofilm samples and measured physicochemical environmental variables at 29 sites distributed longitudinally in the Green-Duwamish River basin, Washington, USA. We characterized catchment-wide patterns of gram-negative fecal indicator bacteria and hypothesized that the presence of antibiotic resistance would be associated with environmental heterogeneity, bacterial primary ecology, stream compartment, and stream type. Antibiotic resistance was determined by microbial growth on selective media supplemented with 3 different antibiotics (ampicillin, chloramphenicol, or tetracycline). Phenotypic antibiotic resistance was positively associated with disturbance, but resistance to at least 1 antibiotic was also detected in undeveloped river segments, with an 83% overall detection rate (i.e., 24 out of 29 sites, 17 in the mainstem and 7 in tributaries). The most probable number of Escherichia coli was associated with higher levels of antibiotic resistance of non- E. coli coliforms across the basin (ρ = 0.38, p < 0.01) but was not associated with antibiotic resistance of E. coli . Phenotypic resistance was highest among non- E. coli coliforms in the water column of tributaries draining moderately to extensively developed subcatchments. Generalized linear mixed-effects model results showed that 18% of the variance in presence of antibiotic resistance was explained by the fixed effects (summed CV across environmental variables, stream type, primary ecology, and stream compartment), and when a spatial random effect was included, the model explained 27% of the variance. Our study provides new evidence that environmental factors and bacterial primary ecology are important underlying factors associated with spatial patterns of antibiotic resistant enteric coliforms. We used macroecological concepts and a riverscape approach to characterize the distribution of antibiotic resistance with methods applicable to municipalities.

Freshwater Science↗
USGS2016

A long-term study of ecological impacts of river channelization on the population of an endangered fish: Lessons learned for assessment and restoration

Projects to assess environmental impact or restoration success in rivers focus on project-specific questions but can also provide valuable insights for future projects. Both restoration actions and impact assessments can become “adaptive” by using the knowledge gained from long-term monitoring and analysis to revise the actions, monitoring, conceptual model, or interpretation of findings so that subsequent actions or assessments are better informed. Assessments of impact or restoration success are especially challenging when the indicators of interest are imperiled species and/or the impacts being addressed are complex. From 1997 to 2015, we worked closely with two federal agencies to monitor habitat availability for and population density of Roanoke logperch ( Percina rex ), an endangered fish, in a 24-km-long segment of the upper Roanoke River, VA. We primarily used a Before-After-Control-Impact analytical framework to assess potential impacts of a river channelization project on the P. rex population. In this paper, we summarize how our extensive monitoring facilitated the evolution of our (a) conceptual understanding of the ecosystem and fish population dynamics; (b) choices of ecological indicators and analytical tools; and (c) conclusions regarding the magnitude, mechanisms, and significance of observed impacts. Our experience with this case study taught us important lessons about how to adaptively develop and conduct a monitoring program, which we believe are broadly applicable to assessments of environmental impact and restoration success in other rivers. In particular, we learned that (a) pre-treatment planning can enhance monitoring effectiveness, help avoid unforeseen pitfalls, and lead to more robust conclusions; (b) developing adaptable conceptual and analytical models early was crucial to organizing our knowledge, guiding our study design, and analyzing our data; (c) catchment-wide processes that we did not monitor, or initially consider, had profound implications for interpreting our findings; and (d) using multiple analytical frameworks, with varying assumptions, led to clearer interpretation of findings than the use of a single framework alone. Broader integration of these guiding principles into monitoring studies, though potentially challenging, could lead to more scientifically defensible assessments of project effects.

Water↗
USGS2026

Tracking Pacific salmon migrations with a prototype eDNA autosampler

Pacific salmon ( Oncorhynchus spp.) are keystone species that support commercial and recreational fisheries and play a significant role in Indigenous cultures. As a keystone species, they are commonly monitored to assess population metrics and adult and juvenile migration. Environmental DNA (eDNA) has been successfully applied to salmon monitoring, but these efforts have relied on manually collected samples which can limit temporal resolution and increase field effort. Here, we evaluated a prototype autonomous eDNA sampler for fine-scale tracking of adult salmon migrations in the Lake Washington Ship Canal (LWSC) in Washington state, USA. The autosampler was deployed approximately 3 km upstream of the Ballard Locks, where returning adult salmon are counted daily, for 4 months during the adult salmon return in 2022, and it collected eDNA samples twice daily (day and night) onto self-preserving filters. We tested eDNA samples for Chinook Salmon ( Oncorhynchus tshawytscha ), Sockeye Salmon ( O. nerka ) and Coho Salmon ( O. kisutch ) and results were compared with daily adult counts at the Ballard Locks. eDNA detection lagged visual counts by approximately 5 days for Sockeye and Coho salmon and approximately 23 days for Chinook Salmon. The extensive time lag in eDNA detection for Chinook Salmon was likely due to a thermal barrier, delaying their migration through the LWSC. We found no clear effect of day versus night sampling on eDNA detection probability. Two additional experiments were performed: one to assess eDNA degradation on used self-preserving filters stored in the autosampler and another to assess whether our 3 L system flush volume was sufficient to prevent residual eDNA from being carried over from one sample to the next. We found no apparent eDNA degradation but potential for sample-to-sample carry over at this flush volume. Our study highlights the need to consider strategic placement of the autosampler intake to optimize eDNA capture and testing of flush volumes to minimize sample-to-sample carryover. Autonomous eDNA sampling provided efficient, high-frequency, and fine-scale surveillance of salmon migrations and offers a scalable approach for a wide variety of monitoring applications.

Washington↗
USGS2023

Spatiotemporal variations in copper, arsenic, cadmium, and zinc concentrations in surface water, fine-grained bed sediment, and aquatic macroinvertebrates in the upper Clark Fork Basin, western Montana—A 20-year synthesis, 1996–2016

The legacy of mining-related contamination in the upper Clark Fork Basin created an extensive longitudinal gradient in metal concentrations, extending from Silver Bow Creek to Lake Pend Oreille, Idaho. Downstream metal concentrations continue to decline, but, despite such improvements, the ecological health of much of the river remains uncertain. Understanding the long-term consequences of the Clark Fork River mining legacy may be supported by environmental monitoring techniques that include a holistic assessment of biological health or response to define organism exposure to complex contaminant mixtures and the consequences of such exposures. This report presents the spatiotemporal patterns of mining-related contaminants, copper, arsenic, cadmium, and zinc, in surface water, fine-grained bed sediment, and macroinvertebrate (aquatic insect) tissue in the upper Clark Fork from near Butte to Missoula, Montana. Overall, the patterns in water column sample concentrations observed in this study were consistent with previously observed trends, but bed sediment concentrations and concentrations of copper and arsenic varied more in tissue samples among sites. Trace element concentrations, especially copper, often exceeded the chronic aquatic life criteria and consistently exceeded the sediment probable effects level PEL for copper, particularly in the upper and middle river segments. The 20 years considered here were the wettest period since remediation started, and this increase in precipitation may have affected patterns in contaminant concentrations. Results of this study demonstrated the utility of a continued, comprehensive biomonitoring program to help guide and evaluate future environmental cleanup activities in the Clark Fork. Despite variation in defining complete restoration in these watersheds, using multiple lines of evidence in this study provided quantifiable measures of the timing and completeness of recovery relative to reference conditions. Successful recovery in the Clark Fork may benefit from an adaptive management strategy to continue collecting a comprehensive, multivariate dataset to evaluate whether established goals are being met and for subsequent adjustments and management, as needed.

Montana↗
USGS2007

A comparison of macroinvertebrate and habitat methods of data collection in the Little Colorado River Watershed, Arizona 2007

The Arizona Department of Environmental Quality (ADEQ) and the U.S. Environmental Protection Agency (USEPA) Ecological Monitoring and Assessment Program (EMAP), use different field methods for collecting macroinvertebrate samples and habitat data for bioassessment purposes. Arizona’s Biocriteria index was developed using a riffle habitat sampling methodology, whereas the EMAP method employs a multi-habitat sampling protocol. There was a need to demonstrate comparability of these different bioassessment methodologies to allow use of the EMAP multi-habitat protocol for both statewide probabilistic assessments for integration of the EMAP data into the national (305b) assessment and for targeted in-state bioassessments for 303d determinations of standards violations and impaired aquatic life conditions. The purpose of this study was to evaluate whether the two methods yield similar bioassessment results, such that the data could be used interchangeably in water quality assessments. In this Regional EMAP grant funded project, a probabilistic survey of 30 sites in the Little Colorado River basin was conducted in the spring of 2007. Macroinvertebrate and habitat data were collected using both ADEQ and EMAP sampling methods, from adjacent reaches within these stream channels. All analyses indicated that the two macroinvertebrate sampling methods were significantly correlated. ADEQ and EMAP samples were classified into the same scoring categories (meeting, inconclusive, violating the biocriteria standard) 82% of the time. When the ADEQ-IBI was applied to both the ADEQ and EMAP taxa lists, the resulting IBI scores were significantly correlated (r=0.91), even though only 4 of the 7 metrics in the IBI were significantly correlated. The IBI scores from both methods were significantly correlated to the percent of riffle habitat, even though the average percent riffle habitat was only 30% of the stream reach. Multivariate analyses found that the percent riffle was an important attribute for both datasets in classifying IBI scores into assessment categories. Habitat measurements generated from EMAP and ADEQ methods were also significantly correlated; 13 of 16 habitat measures were significantly correlated (p<0.01). The visual-based percentage estimates of percent riffle and pool habitats, vegetative cover and percent canopy cover, and substrate measurements of percent fine substrate and embeddedness were all remarkably similar, given the different field methods used. A multivariate analysis identified substrate and flow conditions, as well as canopy cover as important combinations of habitat attributes affecting both IBI scores. These results indicate that similar habitat measures can be obtained using two different field sampling protocols. In addition, similar combinations of these habitat parameters were important to macroinvertebrate community condition in multivariate analyses of both ADEQ and EMAP datasets. These results indicate the two sampling methods for macroinvertebrates and habitat data were very similar in terms of bioassessment results and stressors. While the bioassessment category was not identical for all sites, overall the assessments were significantly correlated, providing similar bioassessment results for the cold water streams used in this study. The findings of this study indicate that ADEQ can utilize either a riffle-based sampling methodology or a multi-habitat sampling approach in cold water streams as both yield similar results relative to the macroinvertebrate assemblage. These results will allow for use of either macroinvertebrate dataset to determine water quality standards compliance with the ADEQ Indexes of Biological Integrity, for which threshold values were just recently placed into the Arizona Surface Water Quality Standards. While this survey did not include warm water desert streams of Arizona, we would predict that EMAP and ADEQ sampling methodologies would provide similar bioassessment results and would not be significantly different, as we have found that the percent riffle habitat in cold and warm water perennial, wadeable streams is not significantly different. However, a comparison study of sampling methodologies in warm water streams should be conducted to confirm the predicted similarity of bioassessment results. ADEQ will continue to implement a monitoring strategy that includes probabilistic monitoring for a statewide ecological assessment of stream conditions. Conclusions from this study will guide decisions regarding the most appropriate sampling methods for future probabilistic monitoring sample plans.

Arizona↗
USGS1984

Assessing the tolerance of fish and fish populations to environmental stress: The problems and methods of monitoring

Environmental stress is an inescapable aspect of life in the aquatic environment. The chemical and physical demands of life underwater impose somewhat rigorous constraints on aquatic species (Smith, 1982a). Superimposed on such demands may be the additional. physiological constraints of particular ecological niches. It is true that aquatic species are adapted to these conditions, but this does not imply the absence of energy drains (Lugo, 1978). For example, thermophilic fishes must still cope physiologically with the demands of high temperatures even though they are adapted to high temperatures per se.

Book chapter↗
USGS1989

Applicability of ambient toxicity testing to national or regional water-quality assessment

Comprehensive assessment of the quality of natural waters requires a multifaceted approach. Based on experimentation designed to monitor responses of organisms to environmental stresses, toxicity testing may have diverse purposes in water quality assessments. These purposes may include identification that warrant further study because of poor water quality or unusual ecological features, verification of other types of monitoring, or assessment of contaminant effects on aquatic communities. A wide variety of toxicity test methods have been developed to fulfill the needs of diverse applications. The methods differ primarily in the full selections made relative to four characteristics: (1) test species, (2) endpoints (acute or chronic), (3) test enclosure type, and (4) test substance (toxicant) that functions as the environmental stress. Toxicity test approachs vary in their capacity to meet the needs of large-scale assessments of existing water quality. Ambient testing is more likely to meet these needs than are the procedures that call for exposure of the test organisms to known concentrations of a single toxicant. However, meaningful interpretation of ambient test results depend on the existence of accompanying chemical analysis of the ambient media. The ambient test substance may be water or sediments. Sediment tests have had limited application, but they are useful because of the fact that most toxicants tend to accumulate in sediments, and many test species either inhabit the sediments or are in frequent contact with them. Biochemical testing methods, which have been developing rapidly in recent years, are likely to be among the most useful procedures for large-scale water quality assessments. They are relatively rapid and simple, and more importantly, they focus on biochemical changes that are the initial responses of virtually all organisms to environmental stimuli. Most species are sensitive to relatively few toxicants and their sensitivities vary as conditions change. One of the most informative approaches for toxicity testing is to combine biochemical tests with other test methods in a ' battery or tests ' that is diversified enough to characterize different types of toxicants and different trophic levels. (Lantz-PTT)

Open-File Report↗
USGS2021

Effects of environmental clutter on synthesized chiropteran echolocation signals in an anechoic chamber

Ultrasonic bat detectors are useful for research and monitoring purposes to assess occupancy and relative activity of bat communities. Environmental “clutter” such as tree boles and foliage can affect the recording quality and identification of bat echolocation calls collected using ultrasonic detectors. It can also affect the transmission of calls and recognition by bats when using acoustic lure devices to attract bats to mist-nets. Bat detectors are often placed in forests, yet automatic identification programs are trained on call libraries using echolocation passes recorded largely from open spaces. Research indicates that using clutter-recorded calls can increase classification accuracy for some bat species and decrease accuracy for others, but a detailed understanding of how clutter impacts the recording and identification of echolocation calls remains elusive. To clarify this, we experimentally investigated how two measures of clutter (i.e., total basal area and number of stems of simulated woody growth, as well as recording angle) affected the recording and classification of a synthesized echolocation signal under controlled conditions in an anechoic chamber. Recording angle (i.e., receiver position relative to emitter) significantly influenced the probability of correct classification and differed significantly for many of the call parameters measured. The probability of recording echo pulses was also a function of clutter but only for the detector angle at 0° from the emitter that could receive deflected pulses. Overall, the two clutter metrics were overshadowed by proximity and angle of the receiver to the sound source but some deviations from the synthesized call in terms of maximum, minimum, and mean frequency parameters were observed. Results from our work may aid efforts to better understand underlying environmental conditions that produce false-positive and -negative identifications for bat species of interest and how this could be used to adjust survey accuracy estimates. Our results also help pave the way for future research into the development of acoustic lure technology by exploring the effects of environmental clutter on ultrasound transmission.

Acoustics↗
USGS2013

Northern Great Plains Network water quality monitoring design for tributaries to the Missouri National Recreational River

The National Park Service (NPS) organized more than 270 parks with important natural resources into 32 ecoregional networks to conduct Inventory and Monitoring (I&M) activities for assessment of natural resources within park units. The Missouri National Recreational River (NRR) is among the 13 parks in the NPS Northern Great Plain Network (NGPN). Park managers and NGPN staff identified surface water resources as a high priority vital sign to monitor in park units. The objectives for the Missouri NRR water quality sampling design are to (1) assess the current status and long-term trends of select water quality parameters; and (2) document trends in streamflow at high-priority stream systems. Due to the large size of the Missouri River main stem, the NGPN water quality design for the Missouri NRR focuses on wadeable tributaries within the park unit. To correlate with the NGPN water quality protocols, monitoring of the Missouri NRR consists of measurement of field core parameters including dissolved oxygen, pH, specific conductance, and temperature; and streamflow. The purpose of this document is to discuss factors examined for selection of water quality monitoring on segments of the Missouri River tributaries within the Missouri NRR. Awareness of the complex history of the Missouri NRR aids in the current understanding and direction for designing a monitoring plan. Historical and current monitoring data from agencies and entities were examined to assess potential NGPN monitoring sites. In addition, the U.S. Environmental Protection Agency 303(d) list was examined for the impaired segments on tributaries to the Missouri River main stem. Because major tributaries integrate water quality effects from complex combinations of land use and environmental settings within contributing areas, a 20-mile buffer of the Missouri NRR was used to establish environmental settings that may impact the water quality of tributaries that feed the Missouri River main stem. For selection of monitoring sites, anthropogenic and natural influences to water quality were assessed for Missouri NRR tributaries. Factors that were examined include the size and contributions of tributaries within watersheds to the main stem; population density; and land use such as urban development and agricultural practices including concentrated animal feeding operations. Based on examination of these data in addition to the park’s legislation and management considerations, two sites were selected for monitoring water quality on Missouri NRR tributaries for the ice-free season (mid-May to mid-October) on a rotational basis every third year. Bow Creek at St. James was selected for water quality monitoring based on lack of long-term water quality monitoring, current recreational use, and proximity of the tributary to intense agricultural practices. In addition, land within the Bow Creek watershed is owned by the NPS. The Niobrara River at Verdel was selected for monitoring due to high use for public recreational activities, adjacent agricultural land use, and documented impairments for designated beneficial uses. Both sites will have access to real-time streamgages that will aid in a greater understanding of water quality.

Natural Resource Technical Report↗
USGS2024

Critical considerations for communicating environmental DNA science

The economic and methodological efficiencies of environmental DNA (eDNA) based survey approaches provide an unprecedented opportunity to assess and monitor aquatic environments. However, instances of inadequate communication from the scientific community about confidence levels, knowledge gaps, reliability, and appropriate parameters of eDNA-based methods have hindered their uptake in environmental monitoring programs and, in some cases, has created misperceptions or doubts in the management community. To help remedy this situation, scientists convened a session at the Second National Marine eDNA Workshop to discuss strategies for improving communications with managers. These include articulating the readiness of different eDNA applications, highlighting the strengths and limitations of eDNA tools for various applications or use cases, communicating uncertainties associated with specified uses transparently, and avoiding the exaggeration of exploratory and preliminary findings. Several key messages regarding implementation, limitations, and relationship to existing methods were prioritized. To be inclusive of the diverse managers, practitioners, and researchers, we and the other workshop participants propose the development of communication workflow plans, using RACI (Responsible, Accountable, Consulted, Informed) charts to clarify the roles of all pertinent individuals and parties and to minimize the chance for miscommunications. We also propose developing decision support tools such as Structured Decision-Making (SDM) to help balance the benefits of eDNA sampling with the inherent uncertainty, and developing an eDNA readiness scale to articulate the technological readiness of eDNA approaches for specific applications. These strategies will increase clarity and consistency regarding our understanding of the utility of eDNA-based methods, improve transparency, foster a common vision for confidently applying eDNA approaches, and enhance their benefit to the monitoring and assessment community.

Environmental DNA↗
USGS2009

Applications of stable isotopes for regional to national-scale water quality and environmental monitoring programs

Isotopes are a potentially powerful component of monitoring and assessment programs aimed at quantifying and mitigating alterations to environments from human activities. In particular, isotopic techniques have proved useful for tracing sources and sinks of various pollutants in large river basins, wetlands, and airsheds. Many of these studies have been conducted at the regional to national scale by building on existing large-scale water, air, and ecological monitoring programs managed by federal and state agencies, and demonstrate the usefulness of isotopes as a complement to standard chemical and hydrological mass balance methods. This chapter presents an overview of how nitrate, particulate organic matter, and water isotopes can be used to interpret spatial patterns and temporal changes in pollution sources, biogeochemical processes, and ecosystem function in watersheds, at the regional to national scale. Examples from several recent and ongoing studies are presented. From the insights developed using varied sampling strategies and isoscapes, we suggest guidelines for future studies in biologically active and human-impacted rivers.

Book chapter↗
USGS2020

Stressor identification framework of biological impairment in Mississippi streams to support watershed restoration and TMDL development

The Clean Water Act (CWA) requires States to identify waters that are impaired for designated uses. These waters are published through a State’s §303(d) list. The CWA also requires that a total maximum daily load (TMDL) be completed for each water body to calculate the maximum amount of contaminants that can be present in that water body and still meet water-quality standards. The Mississippi Department of Environmental Quality (MDEQ) uses a statewide monitoring and assessment strategy to collect benthic macroinvertebrate community data to assess the health of streams and rivers and to identify impaired waters. Waters that are found to be impaired based on the macroinvertebrate community data are listed on the Mississippi §303(d) list, and the cause of impairment is listed as “biological impairment.” Although the CWA requires TMDLs to be developed for applicable contaminants identified in the §303(d) list, TMDLs cannot be computed for stream reaches in Mississippi listed for biological impairment because the actual stressors causing the impairment have not yet been determined. The MDEQ and other water-resource managers in Mississippi require a framework for stressor identification in biologically impaired streams and rivers. This report is organized to (1) provide a general overview of biological impairment and stressor identification in stream ecosystems and (2) provide a detailed framework for stressor identification of Mississippi streams that are biologically impaired. The intent is for the framework to reduce subjectivity, provide consistency, and allow for adaptation as the science evolves. The stressor identification framework for Mississippi involves six key steps: Define the impairment, List the candidate causes of impairment and develop a conceptual model, Compile all relevant data, Evaluate the data, Identify probable causes of impairment by using a weight-of-evidence approach, and Generate a report of results.

Mississippi↗
USGS2024

Widespread occupancy of the endangered northern myotis on northeastern Atlantic Coastal Plain islands

Northern myotis Myotis septentrionalis are one of the bat species most affected by white-nose syndrome (WNS), and disease-induced declines may cause compounding effects when combined with other threats such as habitat loss and fragmentation. Recent evidence suggests that peripheral populations are persisting in post-WNS years; however, the environmental factors that influence the occurrence of this species along the Atlantic Coastal Plain are virtually unknown. We conducted a large-scale acoustic survey on 3 islands: Long Island, New York, and Martha’s Vineyard and Nantucket, Massachusetts, USA, and used a multi-scale occupancy modeling approach to determine the landscape and abiotic factors affecting the distribution of northern myotis. Our estimates of occupancy and detection probability suggest widespread presence across the islands. At the local (200 m) scale, we identified strong negative effects of development on Long Island and Nantucket and a strong positive effect of forest habitat on Martha’s Vineyard. None of the variables we measured sufficiently explained the landscape (1 km 2 ) occupancy of this species, which was very high (ψ = 0.81–0.97), representing an outlier for this species in the post-WNS landscape. The lack of association at the landscape scale suggests that general differences in land cover are not a driving factor of higher occupancy of peripheral northern myotis populations, while local site- specific conditions may be supporting critical foraging or roosting habitat. Because islands are particularly vulnerable to human-driven habitat alteration due to the constraint of limited space, and development pressure is expected to increase, this study provides a baseline to enable managers to assess the effects of future environmental disturbances and monitor population trends to support long-term survival of northern myotis.

Massachusetts, New York↗
USGS1993

Flow recommendations for maintaining riparian vegetation along the Upper Missouri River, Montana

Montana Power Company, Inc. (MPC) submitted a final license application to the Federal Energy Regulatory Commission (FERC) on November 30, 1992. In this application, MPC proposed a plan for the protection of fish, wildlife, habitat, and water-quality resources. One concern was maintenance of woody riparian vegetation along the Missouri River, especially along the Wild and Scenic reach of the river, where the riparian forest occurs in relatively small discontinuous stands. The objectives of this project were 1) to recommend flows that would protect and enhance riparian forests along the Missouri River, and 2) to develop elements of an environmental monitoring program that could be used to assess the effectiveness of the recommended flows. Plains cottonwood ( Populus deltoides subsp. monilifera ) is the key structural component of riparian forests along the Missouri River. Therefore, we focused our analysis on factors affecting populations of this species. Previous work had demonstrated that the age structure of cottonwood populations is strongly influenced by aspects of flow that promote successfully establishment. In this study our approach was to determine the precise age of plains cottonwood trees growing along the Upper Missouri River and to relate years of establishment to the flow record. Our work was carried out between Coal Banks Landing and the Fred G. Robinson Bridge within the Wild and Scenic portion of the Missouri River. This segment of the river occupies a narrow valley and exhibits little channel migration. Maps and notes from the journals of Lewis and Clark (1804-1806) suggest that the present distribution and abundance of cottonwoods within the study reach is generally similar to presettlement conditions. Flows in the study reach are influenced by a number of dams and diversions, most importantly, Canyon Ferry and Tiber Dams. Although flow regulation has decreased peak flows and increased low flows, the gross seasonal pattern of flow has not been greatly altered. Most cottonwood establishment in our study reach occurred in years with a peak mean daily flow greater than 1,400 m 3 /s (49,434 cfs), or in the two years following such a flow. These years include 35 out of the 111 years of record, and account for establishment of 47 of 60 trees examined, a highly significant relationship. Infrequent establishment of cottonwood trees is not the result of scarcity of seed or seedlings. In the study reach seedlings become established most years on bare, relatively low surfaces deposited by the river. However, the high elevation of establishment of all trees dating to before 1978 indicates that only individuals established on high flood deposits are able to survive subsequent floods and ice jams. In order to maintain the present abundance of plains cottonwood in the study area we recommend flood flows in excess of 1,400 m 3 /s (49,434 cfs) measures as mean daily discharge at Fort Benton (U.S. Geological Survey gage 06090800) with a recurrence interval of approximately 9 years. Because cottonwood seeds remain viable for only a few weeks, and because seedling require a moist, bare surface, we further recommend maintenance of the historic timing of flooding with peak flood flows occurring between mid-May and late-June. Flow is not the only factor influencing cottonwood regeneration along this reach of the Missouri River. Land management, especially cattle grazing, is clearly having an impact, and changes in cottonwood populations could be expected if these practices were altered. However, the dependence of cottonwood establishment on high flow is clear in this reach in spite of the effects of other factors. Given the value of the resource, we strongly suggest establishment of a monitoring program to determine the effectiveness of the recommended flows and to provide the data necessary for refining them. We recommend a monitoring program that would include: 1) ten permanent, widely space channel cross sections for annual measurement of channel geometry and cottonwood establishment, growth, and survival; 2) five livestock enclosures to monitor the influence of grazing in the study area; and 3) low-elevation aerial photography of the reach every five years and after every flood to detect changes in channel geometry and forested area. Because cottonwood establishment is episodic, a long-term commitment to the monitoring effort is essential. In addition, cross sections and exclosures should be easy enough to access that measurements during flood years are possible.

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