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Comment on the International Atomic Energy Agency Report on the Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrological Investigation, Vienna, Austria, September 19-21, 1983

According to U.S. Geological Survey records, a report prepared by R. Gonfiantini summarizing the findings and recommendations of the 1983 Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrologic Investigations held in Vienna does not accurately represent the consultants ' consensus on three important points. The consultants (1) recommended no value for the C02-H20 oxygen isotope fractionation factor, not the cited value of 1.04115, (2) adopted a value of 1.0309 rather than 1.03086 to relate the PDB and SMOW scales, and (3) adopted a firm 180 value of -2.20% for NBS-19 on the PDB scale rather than agreeing that this would be a tentative value subject to modification when more measurements in selected laboratories are available. (USGS)

Water-Resources Investigations Report

A validation of satellite derived cyanobacteria detections with state reported events and recreation advisories across U.S. lakes

Cyanobacteria harmful algal blooms (cyanoHABs) negatively affect ecological, human, and animal health. Traditional methods of validating satellite algorithms with data from water samples are often inhibited by the expense of quantifying cyanobacteria indicators in the field and the lack of public data. However, state recreation advisories and other recorded events of cyanoHAB occurrence reported by local authorities can serve as an independent and publicly available dataset for validation. State recreation advisories were defined as a period delimited by a start and end date where a warning was issued due to detections of cyanoHABs over a state's risk threshold. State reported events were defined as any event that was documented with a single date related to cyanoHABs. This study examined the presence-absence agreement between 160 state reported cyanoHAB advisories and 1,343 events and cyanobacteria biomass estimated by a satellite algorithm called the Cyanobacteria Index (CI cyano ). The true positive rate of agreement with state recreation advisories was 69% and 60% with state reported events. CI cyano detected a reduction or absence in cyanobacteria after 76% of the recreation advisories ended. CI cyano was used to quantify the magnitude, spatial extent, and temporal frequency of cyanoHABs; each of these three metrics were greater ( r > 0.2) during state recreation advisories compared to non-advisory times with effect sizes ranging from small to large. This is the first study to quantitatively evaluate satellite algorithm performance for detecting cyanoHABs with state reported events and advisories and supports informed management decisions with satellite technologies that complement traditional field observations.

Harmful Algae

Report of the Federal Advisory Committee on the Bird Banding Laboratory

In the fall of 2005, the Directors of the U.S. Geological Survey (USGS) and the U.S. Fish and Wildlife Service (FWS) determined that to ensure that the Bird Banding Laboratory (BBL) of the USGS maintains and continues its important support of conservation and management of birds, it should be guided by a clear vision for the future. In order to carry out this task, they impaneled a fourteen-member Federal Advisory Committee (FAC) on the Bird Banding Laboratory. It was made up of representatives of the broad bird-banding community, public and private, and was cochaired by a senior representative from each agency. The Committee met four times and a writing subgroup met three times over the course of its work. The Committee identified a new vision and mission for the BBL and identified six goals that it believes should be integral to the development of a strategic plan to achieve them. Those goals are: 1. Facilitate the identification of individual birds through marking. 2. Create automated, electronic systems that efficiently verify, accept, store, and manage data associated with individually marked birds. 3. Facilitate access to and use of data from marked birds for science, conservation, and management. 4. Administer permits in an efficient, timely, and modern manner, and use them to ensure that bird welfare and data quality remain top priorities. 5. Work closely with national and international partners to achieve the mission of the BBL. 6. Manage the BBL in an efficient, cost-effective manner to maximize use of available resources. Most of the report is structured around these goals. The Committee made 2 programmatic recommendations and identified 23 objectives and 58 specific recommendations. The programmatic recommendations are: (1) that the primary role of the BBL is and should continue to be to support the use of banding and banding data by researchers and managers engaged in science, conservation, and management of birds, and not to play a lead role in original research; and (2) that the BBL be managed nationally by USGS headquarters as a research and operational support unit and provided with the resources appropriate to its national and international functions and responsibilities; it should continue to be located physically at the Patuxent Wildlife Research Center (PWRC). In order to achieve its vision and mission, the Committee believes that the BBL must work towards achieving all of the recommendations in this report. Nevertheless, it identified five objectives that stand out as high priority, and they are as follows: *Objective 1.1?to ensure a continuing, adequate supply of high-quality, Federally issued numeric bands of required sizes, materials, and types; *Objective 2.1?to improve mechanisms for verifying, accepting, storing, and managing bird-banding data; *Objective 2.3?to accommodate recapture data; *Objective 4.1?to ensure through the permitting process that banders know how to safely handle birds, collect data accurately, and maintain birds in humane and healthful conditions; and *Objective 5.3?to encourage the development of banding programs in Latin America and the Caribbean. Finally, this Committee believes that the BBL will be well served if it continues to support a Federal Advisory Committee, composed similarly to this one, to continue offering guidance and direction from the broad bird-banding community.

Circular

Mercury in stream ecosystems -- New studies initiated by the U.S. Geological Survey

Mercury can adversely affect humans and wildlife through consumption of contaminated fish, particularly by sensitive individuals, such as children and women of childbearing age. Mercury is currently the leading cause of impairment in the Nation’s estuaries and lakes and was cited in nearly 80 percent of fish-consumption advisories (2,242 of 2,838) reported by states in 2000. The geographic extent of mercury advisories covers more than 10 million acres of lakes and more than 400,000 stream miles—increases of about 7 and 48 percent, respectively, over advisories reported in 1998 (U.S. Environmental Protection Agency, 2002a).

Fact Sheet

Reforestation to enhance Appalachian mined lands as habitat for terrestrial wildlife

Surface mining is widespread throughout the Appalachian coalfield, a region with extensive forests that are rich in wildlife. Game species for hunting, non-game wildlife species, and other organisms are important contributors to sustainable and productive ecosystems. Although small breaks in the forest canopy are important to wildlife diversity, most native Appalachian wildlife species require primarily forested habitats. This Forest Reclamation Advisory provides guidance on reforestation practices to provide high quality habitat for native forest wildlife on Appalachian coal mines.

Forest Reclamation Advisory

Achieving water quality goals in the Chesapeake Bay: A comprehensive evaluation of system response

A Comprehensive Evaluation of System Response Achieving Water Quality Goals in the Chesapeake Bay: A Comprehensive Evaluation of System Response (CESR) includes an evaluation of why progress toward meeting the TMDL and water quality standards has been slower than expected and offers options for how progress can be accelerated. This report is a summation of a three year investigation into the 40 year effort to reduce nutrient loads to Chesapeake Bay. History The effort began as a STAC independent initiative in March 2019, after Kurt Stephenson, Zach Easton, and Brian Benham proposed the idea of a report that would identify gaps and uncertainties in system response—physical, chemical, biological, and socioeconomic—that impact efforts designed to attain water quality standards in Chesapeake Bay. As STAC Chair at the time, Benham facilitated the development of a collaborative process that would engage the entire committee. As a first step in approaching the long causal chain that links management actions to their eventual impact on water quality and living resources, workgroups were formed around the subsystems of this chain: nutrient and sediment reductions (watershed), water quality response to nutrient and sediment reductions (estuary) and living resource response to water quality (living resources). Each of these workgroups generated an independent document with a self-determined scope (i.e., workgroups were afforded flexibility to address issues beyond the original objectives). Because the content of each document was both unique and substantial, STAC chose to publish them as stand-alone documents with authorship attribution. In the second step, a steering committee developed a series of framing questions to guide the preparation of this report that would meet the objective of identifying gaps and uncertainties in achieving the Bay TMDL and water quality standards. Coeditors Stephenson and Wardrop, supported to great extent by a subgroup of the Steering Committee (Leonard Shabman, Zach Easton, Jeremy Testa, William Dennison, Kenny Rose, and Mark Monaco) were tasked with assembling ideas and contributions to write a single draft text, drawing material from the aforementioned resource documents, STAC and Chesapeake Bay Program reports, the scientific literature, and a limited amount of additional analyses performed in collaboration with Bay Program scientists. The resulting report was then submitted for several reviews by both steering committee members and the membership at-large to produce a consensus report.

Maryland, Virginia

Special topic—Eruption plumes and clouds

Introduction Explosive eruptions create plumes of volcanic ash and gas that can rise more than 30,000 feet (9.1 kilometers [km]) above sea level within minutes of eruption onset. The resulting clouds disperse under prevailing winds and may cause hazardous conditions hundreds to thousands of kilometers from the volcano, including in international airspace. Rapid detection and characterization of explosive activity is vital to mitigate the wide-ranging effects of volcanic ash. Ashfall thicknesses as small as a millimeter or so on the ground can affect infrastructure, agriculture, and air quality, requiring extensive clean-up procedures (Schuster, 1981; Warrick and others, 1981, U.S. Geological Survey, 2022). Volcanic clouds also pose substantial threats to aircraft. Since 1953, 88 encounters between airplanes and ash clouds have been documented worldwide (International Civil Aviation Organization, 2015, appendix F), resulting in aircraft damage and, in 9 cases, engine failure (Guffanti and others, 2010). In 1982, two large passenger planes suffered complete engine failure owing to eruptions in Indonesia (Global Volcanism Program, 1982) and a similar incident occurred over Alaska in 1989 (Casadevall, 1994). In all three cases, they were able to restart some engine capability and land safely once they emerged from the ash clouds, although with substantial damage (Guffanti and others, 2010). The clear threat to aviation has led to establishment of nine Volcanic Ash Advisory Centers (VAAC) around the world to monitor and rapidly disseminate information about volcanic eruptions to the aviation community. U.S. Geological Survey (USGS) volcano observatories issue the Volcano Observatory Notice for Aviation that informs of preeruptive unrest or eruptive activity. When ash-producing eruptions do occur, volcano observatories work closely with their regional VAAC to ensure consistency and accuracy in eruption onset time, cloud altitude, ash production, and duration as reported in Volcanic Ash Advisories. Explosive volcanism in the United States and Commonwealth of the Northern Mariana Islands prompts 50–100 such advisories in any given year (table J1). This collaborative effort is greatly aided by USGS detection and monitoring of eruption clouds to ensure a timely and coordinated response. To support these efforts to provide guidance on ash transport and fallout, the USGS developed the Ash3d volcanic ash dispersion model ( https://vsc-ash.wr.usgs.gov/ash3d-gui ) (Schwaiger and others, 2012). Automated simulations are run daily by the USGS for volcanoes that are in elevated states of unrest, and in response mode when eruptions occur. During eruptions, the model output is provided to local National Weather Service Weather Forecast Offices to guide them in the issuance of their information products (such as special weather statements, ashfall advisories, or ashfall warnings), as well as to State and local governments and the public. Characterization of the eruption source is needed to estimate the parameters used to initialize the Ash3d model, and by the Anchorage and Washington VAACs to initialize other dispersion models that inform forecasts for the airborne volcanic cloud. The source parameters that can be provided by observation during an eruption include eruption start time, eruption cloud height over time, and eruption duration. Other, nonobservable source parameters, such as mass eruption rate and grain-size distribution, are based on empirical correlations and study of historical deposits. The goal is to provide a time series of cloud heights, mass eruption rates, and particle-size distributions that accurately reflects current conditions. When feasible, the USGS also provides guidance on the nature of ongoing eruptions and forecasts future activity using petrologic monitoring of collected tephra samples. The aims of providing accurate observable parameters are achieved through analysis of (1) near-real-time meteorological satellite data, (2) ground-based cameras (see of Flinders, A.F., Lowenstern, J.B., Coombs, M.L., and Poland, M.P., eds., Recommended capabilities and instrumentation for volcano monitoring in the United States: U.S. Geological Survey Scientific Investigations Report 2024–5062–G, 11 p., https://doi.org/10.3133/sir20245062g.">chapter G , this volume; Orr and others, 2024), (3) weather radar, (4) volcanic lightning detection, and (5) ground-based ash sensors and sampling. Explosive eruptions can be detected by a variety of geophysical monitoring, including infrasound (see of Flinders, A.F., Lowenstern, J.B., Coombs, M.L., and Poland, M.P., eds., Recommended capabilities and instrumentation for volcano monitoring in the United States: U.S. Geological Survey Scientific Investigations Report 2024–5062–C, 11 p., https://doi.org/10.3133/sir20245062c.">chapter C , this volume; Lyons and others, 2024) and seismicity (see of Flinders, A.F., Lowenstern, J.B., Coombs, M.L., and Poland, M.P., eds., Recommended capabilities and instrumentation for volcano monitoring in the United States: U.S. Geological Survey Scientific Investigations Report 2024–5062–B, 9 p., https://doi.org/10.3133/sir20245062b.">chapter B , this volume; Thelen and others, 2024). However, those methods cannot quantify the altitude, ash content, and dispersal dynamics of resulting volcanic clouds. Ideally, all available sources of monitoring data are synthesized to develop a coherent understanding of eruptive activity. The guidance summarized here provides a framework for characterizing volcanic clouds in the atmosphere and tracking the evolution of explosive eruption dynamics.

Scientific Investigations Report

Designing a high-frequency nutrient and biogeochemical monitoring network for the Sacramento–San Joaquin Delta, northern California

Executive Summary This report is the third in a series of three reports that provide information about how high-frequency (HF) nutrient monitoring may be used to assess nutrient inputs and dynamics in the Sacramento–San Joaquin Delta, California (Delta). The purpose of this report is to provide the background, principles, and considerations for designing an HF nutrient-monitoring network for the Delta to address high-priority, nutrient-management questions. The report starts with discussion of the high-priority management questions to be addressed, continues through discussion of the questions and considerations that place demands and constraints on network design, discusses the principles applicable to network design, and concludes with the presentation of three example nutrient-monitoring network designs for the Delta. For three example network designs, we assess how they would address high-priority questions that have been identified by the Delta Regional Monitoring Program (Delta Regional Monitoring Program Technical Advisory Committee, 2015). This report, along with the other two reports of this series (Kraus and others, 2017; Downing and others, 2017), was drafted in cooperation with the Delta Regional Monitoring Program to help scientists, managers, and planners understand how HF data improve our understanding of nutrient sources and sinks, drivers, and effects in the Delta. The first report in the series (Kraus and others, 2017) provides an introduction to the reasons for and fundamental concepts behind using HF monitoring measurements, including a brief summary of nutrient status and trends in the Delta and an extensive literature review showing how and where other research and monitoring programs have used HF monitoring to improve our understanding of nutrient cycling. The report covers the various technologies available for HF nutrient monitoring and presents the different ways HF monitoring instrumentation may be used for both fixed station and spatial assessments. Finally, it presents numerous examples of how HF measurements are currently (2017) being used in the Delta to examine how nutrients and nutrient cycling are related to aquatic habitat conditions. The second report in the series (Downing and others, 2017) summarizes information about HF nutrient and associated biogeochemical monitoring in the north Delta. The report synthesizes data available from the nutrient and water quality monitoring network currently (2017) operated by the U.S. Geological Survey in this ecologically important region of the Delta. In the report, we present and discuss the available data at various timescales—first at the monthly, seasonal, and inter-annual timescales; and, second, for comparison, at the tidal and event timescales. As expected, we determined that there is substantial variability in nitrate concentrations at short timescales, such as within a few hours, but also significant variability at longer timescales such as months or years. This high variability affects calculation of fluxes and loads, indicating that HF monitoring is necessary for understanding and assessing flux-based processes and outcomes in Delta tidal environments.

California

Monitoring wildlife for pesticide content

In May 1963, the President's Science Advisory Committee issued a report entitled Use of Pesticides . 17 the President already had requested the responsible federal agencies to implement the recommendations in the report. One of these recommendations was to provide for the development and coordination of a pesticide-monitoring program conducted on a continuing basis, by federal agencies to obtain timely systematic data on pesticide residues in the environment. Many people re engaged in research to learn the quantities of pesticide that may be hazardous. Yet there is concern that hazardous quantities may accumulate before the difficult task of evaluation can be completed. The President's report on environmental pollution 12 expresses the view that the soils and waters of the world cannot indefinitely provide a vast dumping ground to absorb and render harmless all human wastes. Chlorinated hydrocarbon pesticides are only one of these kinds of pollutants, yet they are particularly important because they persist long in the environment and accumulate in the tissues of animals.

National Academy of Sciences NRC Publication

Appendix D: Use of wave scenarios to assess potential submerged oil mat (SOM) formation along the coast of Florida and Alabama

During the Deepwater Horizon oil spill, oil in the surf zone mixed with sediment in the surf zone to form heavier-than-water sediment oil agglomerates of various size, ranging from small (cm-scale) pieces (surface residual balls, SRBs) to large mats (100-m scale, surface residue mats, SR mats). Once SR mats formed in the nearshore or in the intertidal zone, they may have become buried by sand moving onshore or alongshore. To assist in locating possible sites of buried oil, wave scenarios previously developed by the U.S. Geological Survey (USGS) were used to determine the depths at which surface oil had the potential to mix with suspended sediment. For sediment to mix with floating oil and form an agglomerate of sufficient density to sink to the seafloor, either the water must be very shallow (e.g., within the swash zone) or sediment must be suspended to the water surface in sufficient concentrations to create a denser-than-sea water agglomerate. The focus of this study is to analyze suspended sediment mixing with surface oil in depths beyond the swash zone, in order to define the seaward limit of mat formation. A theoretical investigation of sediment dynamics in the nearshore zone revealed that non-breaking waves do not suspend enough sediment to the surface to form sinking sand/oil agglomerates. For this study, it was assumed that the cross-shore distribution of potential agglomerate formation is associated with the primary breaker line, and the presence of plunging breakers, over the time frame of oiling. The potential locations of submerged oil mats (SOMs) are sites where (1) possible agglomerate formation occurred, where (2) sediment accreted post-oiling and buried the SOM, and where (3) the bathymetry has not subsequently eroded to re-expose any mat that may have formed at that site. To facilitate identification of these locations, the range of water level variation over the time frame of oiling was also prescribed, which combined with the wave-breaking depth analysis and pre-oiling bathymetry would identify the potential geographic locations of SOMs.

Operational Science Advisory Team Report

Selected low-flow frequency statistics for continuous-record streamgage locations in Maryland, 2010

According to a 2008 report by the Governor's Advisory Committee on the Management and Protection of the State's Water Resources, Maryland's population grew by 35 percent between 1970 and 2000, and is expected to increase by an additional 27 percent between 2000 and 2030. Because domestic water demand generally increases in proportion to population growth, Maryland will be facing increased pressure on water resources over the next 20 years. Water-resources decisions should be based on sound, comprehensive, long-term data and low-flow frequency statistics from all available streamgage locations with unregulated streamflow and adequate record lengths. To provide the Maryland Department of the Environment with tools for making future water-resources decisions, the U.S. Geological Survey initiated a study in October 2009 to compute low-flow frequency statistics for selected streamgage locations in Maryland with 10 or more years of continuous streamflow records. This report presents low-flow frequency statistics for 114 continuous-record streamgage locations in Maryland. The computed statistics presented for each streamgage location include the mean 7-, 14-, and 30-consecutive day minimum daily low-flow dischages for recurrence intervals of 2, 10, and 20 years, and are based on approved streamflow records that include a minimum of 10 complete climatic years of record as of June 2010. Descriptive information for each of these streamgage locations, including the station number, station name, latitude, longitude, county, physiographic province, and drainage area, also is presented. The statistics are planned for incorporation into StreamStats, which is a U.S. Geological Survey Web application for obtaining stream information, and is being used by water-resource managers and decision makers in Maryland to address water-supply planning and management, water-use appropriation and permitting, wastewater and industrial discharge permitting, and setting minimum required streamflows to protect freshwater biota and ecosystems.

Open-File Report

Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River Fall Chinook Salmon ESU: January 2019 - December 2019

The portion of the Snake River fall Chinook salmon Oncorhynchus tshawytscha evolutionary significant unit (ESU) that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 19922019 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners, (2) phenotypic and numeric responses by natural-origin juveniles, and (3) use of a small unmanned aerial system (sUAS) to search for fall Chinook salmon redds and carcasses. Spawners have located and used most of the available spawning habitat and that habitat is gradually approaching redd capacity. Timing of spawning and fry emergence have been relatively stable, but effects of density dependence are evident in juvenile life stages. Apparent abundance of juvenile fall Chinook salmon has increased and we noted the following responses: parr dispersal from riverine rearing habitat into Lower Granite Reservoir has become earlier; growth rate (g/d) and dispersal size of parr declined; and passage timing of smolts from the two Snake River reaches has become earlier and downstream movement rate faster. These findings coupled with stock-recruitment analyses presented in this report provide evidence for density-dependence in the Snake River reaches and in Lower Granite Reservoir that was influenced by the expansion of the recovery program. The long-term goal is to use this information in a comprehensive modeling effort to conduct action-effectiveness and uncertainty research and to inform Fish Population, Hydrosystem, Harvest, Hatchery, and Predation and Invasive Species Management Research, Monitoring, and Evaluation (RM&E) progams. In 2019, the U.S. Geological Survey (USGS) shifted survey efforts in the Snake River toward deepwater redd searches and fish collection for parentage-based tagging (PBT) analyses because all unmanned aerial system (UAS) activities were suspended by the Department of the Interior two weeks into the spawning season. We counted 81 deepwater redds at 17 of the 29 sites surveyed. Redd depths averaged 3.6 m. We collected a total of 123 live fall Chinook salmon from 16 unique geographic locations that spanned 55 river kilometers. Forty-six fish were recovered at Eureka Bar (rkm 307.1) and Kirby Creek (rkm 352.0), which accounted for 37% of all collected fish in 2019. Most (73 fish) post-spawned salmon were collected from early to mid-November just after peak spawning. A summary of 2019 PBT results can be found in Appendix A.1. In 2019, we PIT tagged subyearling fall Chinook salmon in both the Snake and Clearwater rivers. In the Snake River, we tagged 410 fish with 8-mm tags, 666 fish with 9-mm tags, and 1,082 fish 12-mm tags. During seining, our recapture rate of previously tagged fish was slightly higher in the lower reach at 11.4% than in the upper reach at 10.6%. In an effort to represent more of the population through tagging, we tagged fish as small as 45 mm with 8-mm tags at one site in the upper reach. This allowed us to increase the number of fish tagged in that reach by 17.7%. An additional 10.6% of collected fish could have been tagged in the lower reach had we used 8-mm tags in that reach. In the Clearwater River, we tagged 2,451 subyearlings and recaptured 260 (10.6%) fish in the river and 66 fish (48 tagged by USGS, 18 tagged by the Nez Perce Tribe) at Lower Granite Dam during October to provide information for growth estimation. Within riverine habitats, growth in both length and mass were higher for fish tagged with 8-mm tags than with 9- and 12-mm tags. Estimated growth in length and mass of subyearlings was higher in Lower Granite Reservoir than in riverine habitats. We adapted existing statistical models used to estimate abundance of steelhead and spring/summer Chinook salmon for fall Chinook salmon passing Lower Granite Dam. Run reconstruction efforts to date at Lower Granite Dam for Snake River fall Chinook salmon have provided estimates of the number of returning adults but with no measure of uncertainty about the estimates. The objective of this study was to estimate the abundance, with uncertainty, of marked (coded-wire tagged CWT or adipose clipped) and unmarked fall Chinook salmon past Lower Granite Dam for return years 20032018. Estimating uncertainty is important for informing the state-space life cycle model (Chapter 5), which incorporates both observation and process uncertainty into parameter estimates. The coefficient of variation (CV) for log- abundance was 1.0% or less in all years, whereas the CV for abundance averaged 4.2% and ranged from 1.4% to 10.4% among years. Over the past five years, we have been developing a two-stage state-space life-cycle model for naturally produced fall Chinook salmon in the Snake River basin. Initial efforts focused on generating juvenile and adult abundance estimates, with estimates of uncertainty, for informing the life-cycle model. In this report we 1) describe the statistical life-cycle model and improvements made since our last report to the Independent Scientific Advisory Board (ISAB), 2) estimate the effects of covariates on key demographic parameters, and 3) use the fitted life- cycle model to simulate population trajectories under hydrosystem actions proposed for the NOAA 2020 Biological Opinion (hereafter, the Proposed Action). Major recent advancements to the model include revised juvenile abundance estimates, the ability to estimate smolt-to-adult return rates (SAR) separately for subyearling and yearling juvenile fall Chinook salmon, and improvements in the observation model for estimating age, sex, and outmigration structure in adult returns. We examined the effect of numerous environmental, hydrosystem, and ocean covariates on key demographic parameters but only a few covariates were significant. For the adult-to-juvenile transition, we found the maximum weekly river flows during the winter egg- incubation period had a significant negative effect on the juvenile outmigrant abundance from that brood year. For subyearling outmigrants, percent spill during the summer had a significant positive effect on SAR and the mean winter PDO (Pacific Decadal Oscillation) had a significant negative effect on SAR. For yearling outmigrants, NPGO (North Pacific Gyre Oscillation) had a significant positive effect on SAR. We used the fitted model to simulate population trajectories under the Proposed Action, and the median 10-year geometric mean abundance was 8,222 female spawners (interquartile range: 2,592 26,714). Overall, the probability of quasi- extinction (probability of falling below 50 female spawners for 4 consecutive years) was low, with only 1.6% of all simulations having a quasi-extinction probability >0.95. Although quasi-extinction probability was low, we did not assess the additional effect of climate change, which would be expected to increase quasi-extinction probability.

Idaho, Oregon, Washington

Quality of ground water for selected municipal water supplies in Iowa, 1997–2002 water years

The Iowa ground-water-quality monitoring program has been conducted cooperatively since 1982 by the Iowa Department of Natural Resources, Iowa Geological Survey; the University of Iowa Hygienic Laboratory; and the U.S. Geological Survey. The original objectives of the program were to provide baseline ground-water-quality data throughout the State for the major aquifers and to address any new areas of water-quality concern. Since the program began, the emphasis and objectives of the program have changed several times. As of 1992, greater emphasis has been placed on determining trends in ground-water quality and correlating water quality with possible contributing factors such as location, land use, aquifer, aquifer depth, and precipitation. From 1997 through 2002, a total of 471 samples of untreated water have been collected from 154 municipal wells throughout Iowa. The samples, collected from six different aquifers, consisted of 192 alluvial aquifer samples (36 wells), 79 Pleistocene aquifer samples (16 wells), 52 Cretaceous aquifer samples (35 wells), 48 Carboniferous aquifer samples (30 wells), 54 Silurian-Devonian aquifer samples (19 wells), and 46 Cambrian-Ordovician aquifer samples (18 wells). Some samples had concentrations greater than or equal to the respective Maximum Contaminant Levels for drinking water established by the U.S. Environmental Protection Agency. Of 471 samples analyzed, 19 samples had concentrations greater than or equal to the Maximum Contaminant Level for sulfate; 31 samples had concentrations greater than or equal to the Maximum Contaminant Level for nitrite plus nitrate; 257 samples had concentrations greater than or equal to the Secondary Maximum Contaminant Level for iron; and 249 samples had concentrations greater than or equal to the Secondary Maximum Contaminant Level for manganese. Of the 443 samples analyzed for pesticides, 87 samples had concentrations greater than or equal to the respective minimum reporting levels for the parent compounds, 30 samples had concentrations greater than or equal to the respective minimum reporting levels for pesticide metabolites, and 26 samples had detectable concentrations (censored values) less than the minimum reporting levels. Concentrations of alachlor, atrazine, cyanazine, and metolachlor accounted for about 90 percent of the samples equal to or exceeding the respective minimum reporting levels for pesticides. No samples had pesticide concentrations greater than the respective Maximum Contaminant or Health Advisory Levels. The compact disc included with this report has information about water-quality properties and concentrations of dissolved solids, major ions, nutrients, trace elements, radionuclides, total organic carbon, pesticides, and synthetic organic compounds for water years 1997 through 2002.

Iowa

Occurrence and distribution of fish species in the Great and Little Miami River basins, Ohio and Indiana, pre-1900 to 1998

Historically, 133 fish species representing 25 families have been documented in the Great and Little Miami River Basins. Of these, 132 species have been reported in the basins since 1901, 123 since 1955, 117 since 1980, and 113 post-1990. Natural processes and human activities have both been shown to be major factors in the alteration of fish-community structure and the decrease in species diversity. In the late 1800's, dam construction and the removal of riparian zones restricted fish migration and altered habitat. Industrialization and urbanization increased considerably in the 1900's, further degrading stream habitat and water quality. Species requiring riffles and clean, hard stream bottoms were the most adversely affected. The use of agricultural and industrial chemicals prompted fish-consumption advisories and an increase in studies reporting the occurrence of external fish anomalies. Over the last 20 years, water quality has improved in part because of the upgrading of wastewater-treatment facilities; and, as a result, many streams of the Great and Little Miami River Basins generally meet or exceed existing water-quality standards. Although significant improvements have occurred in the basins, continued efforts to improve water quality and restore the physical habitat of streams will be necessary to increase fish abundance and biodiversity.

Indiana, Ohio