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At least 937 records · Page 52Linked to original sources

USGS1995

Population viability of the Snake River chinook salmon (Oncorhynchus tshawytscha)

In the presence of historical data, population viability models of intermediate complexity can be parameterized and utilized to project the consequences of various management actions for endangered species. A general stochastic population dynamics model with density feedback, age structure, and autocorrelated environmental fluctuations was constructed and parameterized for best fit over 36 years of spring chinook salmon ( Oncorhynchus tshawytscha ) redd count data in five Idaho index streams. Simulations indicate that persistence of the Snake River spring chinook salmon population depends primarily on density-independent mortality. Improvement of rearing habitat, predator control, reduced fishing pressure, and improved dam passage all would alleviate density-independent mortality. The current value of the Ricker α should provide for a continuation of the status quo. A recovery of the population to 1957–1961 levels within 100 years would require an approximately 75% increase in survival and (or) fecundity. Manipulations of the Ricker β are likely to have little or no effect on persistence versus extinction, but considerable influence on population size.

Canadian Journal of Fisheries and Aquatic Sciences↗

USGS2017

Spread dynamics of perennial pepperweed ( Lepidium latifolium ) in two seasonal wetland areas

Perennial pepperweed is an invasive plant that is expanding rapidly in several plant communities in the western United States. In California, perennial pepperweed has aggressively invaded seasonal wetlands, resulting in degradation of habitat quality. We evaluated the rate and dynamics of population spread, assessed the effect of disturbance on spread, and determined the biotic and abiotic factors influencing the likelihood of invasion. The study was conducted at eight sites within two wetland regions of California. Results indicate that in undisturbed sites, spread was almost exclusively through vegetative expansion, and the average rate of spread was 0.85 m yr −1 from the leading edge. Spread in sites that were disked was more than three times greater than in undisturbed sites. While smaller infestations increased at a faster rate compared with larger populations, larger infestations accumulated more newly infested areas than smaller infestations from year to year. Stem density was consistently higher in the center of the infestations, with about 2.4 times more stems per square meter compared with the leading edge at the perimeter of the population. The invasion by perennial pepperweed was positively correlated with increased water availability but was negatively correlated with the cover of perennial and annual species. Thus, high cover of resident vegetation can have a suppressive effect on the rate of invasion, even in wetland ecosystems. On the basis of these results, we recommend that resident plant cover not be disturbed, especially in wet areas adjacent to areas currently infested with perennial pepperweed. For infested areas, management efforts should be prioritized to focus on controlling satellite populations as well as the leading edge of larger infestations first. This strategy could reduce the need for costly active restoration efforts by maximizing the probability of successful re-establishment of resident vegetation from the adjacent seedbank.

Invasive Plant Science and Management↗

USGS2019

Supporting the development and use of native plant materials for restoration on the Colorado Plateau (Fiscal Year 18 Report)

Introduction A primary focus of the Colorado Plateau Native Plant Program (CPNPP) is to identify and develop appropriate native plant materials (NPMs) for current and future restoration projects. Multiple efforts have characterized the myriad challenges inherent in providing appropriate seed resources to enable effective, widespread restoration and identified a broad suite of research activities to provide the information necessary to overcome those challenges (e.g., Plant Conservation Alliance 2015; Breed et al. 2018). Many of the most complex information needs relate to identifying the appropriate plant species and populations that can successfully establish in dryland environments, like the Colorado Plateau, where low and highly variable precipitation is standard. Providing this information requires synergistic research efforts in which results from earlier investigations inform the design of subsequent investigations. Southwest Biological Science Center’s (SBSC’s) research activities in FY18 followed the FY18 Statement of Work (“Research supporting native plant materials development for the Colorado Plateau Native Plant Program, FY18”) to support a research framework that is continually adapting based on the needs of the restoration community and results from previous investigations; the long-term research framework is now outlined in the 2019-2023 5-Year Research Strategy (discussed below; hereafter referred to as the 5-Year Research Strategy). This research framework provides support for the National Seed Strategy for Rehabilitation and Restoration (Plant Conservation Alliance, 2015), Department of Interior Secretarial Order #3347 (Conservation Stewardship and Outdoor Recreation), and Bureau of Land Management Leadership Priority #1 (Create a conservation stewardship legacy second only to Teddy Roosevelt). The overall focus of activities in FY18 centered on landscape genetics and planning for common garden and other research projects. These activities were supported by two biological technicians that were hired and trained by Dr. Rob Massatti and Dr. Daniel Winkler. Many of the field-related activities, including plant trait measurement and seed/tissue collecting, were assigned to these technicians, which freed Dr. Massatti to work on other research objectives, including the time-consuming activities of processing and analyzing genetic data. A major challenge to field work in FY18 was the drought conditions that pervaded the Plateau during the spring field season. Due to low winter and spring precipitation, many plant communities did not green up in the spring, which prevented the biological technicians from collecting plant trait data, tissues samples, and seeds in many areas. To cope with the dry conditions, the technicians searched sites across a wider range of environmental space and considered a broader suite of species from which to collect data (i.e., species that may be included in research projects in future years). Monsoonal precipitation starting in July supported a late summer/fall field season and allowed the technicians to follow a more normal work plan. While Dr. Massatti was the only scientist supported by the SBSC-CPNPP agreement in FY18, other scientists, including Drs. John Bradford, Seth Munson, Mike Duniway, Sasha Reed, Daniel Winkler, and Jayne Belnap, spent a considerable amount of time discussing individual projects and the newly developed 5-Year Research Strategy. Some of these discussions resulted in a publication by Dr. Winkler, in addition to a large group of researchers, practitioners, and others who work on the Colorado Plateau, concerning the restoration challenges facing the Plateau into the future and the types of efforts that may support successful restoration (Winkler et al., 2018).

Colorado↗

USGS2008

GIS technology and models for assessing landslide hazard and risk

Advances in Geographical Information Systems (GIS) technology and the mathematical/statistical tools for modelling and simulation have led to the growing application of quantitative techniques in many areas of the earth sciences. Few disciplines have embraced these developments more enthusiastically than the study of landslide hazards. Because the shape of the land surface plays a fundamental role in landslide processes, much of this new work has been driven by the increasing availability of digital elevation models (DEMs) and the software to manipulate them. As a result, investigators worldwide are devising spatial models to forecast slope instability in efforts to keep landslide hazards from becoming landslide disasters. The methods range from empirical and heuristic to statistical and physically-based. Despite nearly a quarter-century of progress, e.g. since Carrara (1983) , and a veritable “cottage industry” of current DEM-based hazard mapping, many of these spatial predictions either are based on unsuitable data or are not properly modelled.

Geomorphology↗

USGS2002

High-resolution aeromagnetic mapping of volcanic terrain, Yellowstone National Park

High-resolution aeromagnetic data acquired over Yellowstone National Park (YNP) show contrasting patterns reflecting differences in rock composition, types and degree of alteration, and crustal structures that mirror the variable geology of the Yellowstone Plateau. The older, Eocene, Absaroka Volcanic Supergroup, a series of mostly altered, andesitic volcanic and volcaniclastic rocks partially exposed in mountains on the eastern margin of YNP, produces high-amplitude, positive magnetic anomalies, strongly contrasting with the less magnetic, younger, latest Cenozoic, Yellowstone Plateau Group, primarily a series of fresh and variably altered rhyolitic rocks covering most of YNP. The Yellowstone caldera is the centerpiece of the Yellowstone Plateau; part of its boundary can be identified on the aeromagnetic map as a series of discontinuous, negative magnetic anomalies that reflect faults or zones along which extensive hydrothermal alteration is localized. The large-volume rhyolitic ignimbrite deposits of the 0.63-Ma Lava Creek Tuff and the 2.1-Ma Huckleberry Ridge Tuff, which are prominent lithologies peripheral to the Yellowstone caldera, produce insignificant magnetic signatures. A zone of moderate amplitude positive anomalies coincides with the mapped extent of several post-caldera rhyolitic lavas. Linear magnetic anomalies reflect the rectilinear fault systems characteristic of resurgent domes in the center of the caldera. Peripheral to the caldera, the high-resolution aeromagnetic map clearly delineates flow unit boundaries of pre- and post-caldera basalt flows, which occur stratigraphically below the post-caldera rhyolitic lavas and are not exposed extensively at the surface. All of the hot spring and geyser basins, such as Norris, Upper and Lower Geyser Basins, West Thumb, and Gibbon, are associated with negative magnetic anomalies, reflecting hydrothermal alteration that has destroyed the magnetic susceptibility of minerals in the volcanic rocks. Within Yellowstone Lake, which is mostly within the Yellowstone caldera, aeromagnetic lows also are associated with known hydrothermal activity in the lake. Many of the magnetic lows extend beyond the areas of alteration and hot springs, suggesting a more extensive currently active or fossil hydrothermal system than is currently mapped. Steep magnetic gradients, suggesting faults or fractures, bound the magnetic lows. This implies that fractures localize the hot springs. Magnetic gradient trends reflect the mapped Basin and Range structural trends of north and northwest, as well as northeasterly trends that parallel the regional trend of the Snake River Plain and the track of the Yellowstone hot spot which follow the Precambrian structural grain. These trends are found both at small scales such as in hydrothermal basins and at more regional fault scales, which suggests that the regional stress field and reactivated older structures may exert some control on localization of hydrothermal activity. ?? 2002 Elsevier Science B.V. All rights reserved.

Journal of Volcanology and Geothermal Research↗

USGS2010

High resolution near-bed observations in winter near Cape Hatteras, North Carolina

The U.S. Geological Survey (USGS) Coastal and Marine Science Center in Woods Hole, Massachusetts, is leading an effort to understand the regional sediment dynamics along the coastline of North and South Carolina. As part of the Carolinas Coastal Change Processes Project, a geologic framework study in June of 2008 by the Woods Hole Coastal and Marine Science Center's Sea Floor Mapping Group focused on the seaward limit of Diamond Shoals and provided high resolution bathymetric data, surficial sediment characteristics, and subsurface geologic stratigraphy. These data also provided unprecedented guidance to identify deployment locations for tripods and moorings to investigate the processes that control sediment transport at Diamond Shoals. Equipment was deployed at three sites from early January, 2009 through early May, 2009: north and south of the shoals at 15 m depth, and at the tip at 24 m depth. Many strong storm systems were recorded during that time period. Mounted on the tripods were instruments to measure surface waves, pressure, current velocity, bottom turbulence, suspended-sediment profiles, and sea-floor sand-ripple bedforms. Many instruments were designed and programmed to sample in high resolution in time and space, as fast as 8 Hz hourly bursts and as small as 6 cm bin sizes in near bottom profiles. A second tripod at the north site also held a visual camera system and sonar imaging system which document seafloor bedforms. The region is known for its dynamics, and one of the tripods tipped over towards the end of the experiment. A preliminary look at the data suggests the region is characterized by high energy. Raw data from a burst recorded at the south site on Mar. 26 th show instantaneous flow speed at 150 cm/s at 0.5 m above the seabed. This paper reports preliminary highlights of the observations, based on raw data, and lessons learned from a deployment of large tripod systems in such a dynamic location.

North Carolina↗

USGS2009

High resolution near-bed observations in winter near Cape Hatteras, North Carolina

Conference Paper↗

USGS1983

Multiple microtektite horizons in upper Eocene marine sediments: No evidence for mass extinctions

Microtektites have been recovered from three horizons in eight middle Eocene to middle Oligocene marine sediment sequences. Five of these occurrences are coeval and of latest Eocene age (37.5 to 38.0 million years ago); three are coeval and of early late Eocene age (38.5 to 39.5 million years ago); and three are of middle Oligocene age (31 to 32 million years ago). In addition, rare probable microtektites have been found in sediments with ages of about 36.0 to 36.5 million years. The microtektite horizon at 37.5 to 38.0 million years can be correlated with the North American tektite-strewn field, which has a fission track age (minimum) of 34 to 35 million years and a paleomagnetic age of 37.5 to 38.0 million years. There is no evidence for mass faunal extinctions at any of the microtektite horizons. Many of the distinct faunal changes that occurred in the middle Eocene to middle Oligocene can be related to the formation of the Antarctic ice sheet and the associated cooling phenomena and intensification of bottom currents that led to large-scale dissolution of calcium carbonate and erosion, which created areally extensive hiatuses in the deep-sea sediment records. The occurrence of microtektite horizons of several ages and the lack of evidence for faunal extinctions suggest that the effects of extraterrestrial bolide impacts may be unimportant in the biologic realm during middle Eocene to middle Oligocene time.

Science↗

USGS2019

Oyster reefs in northern Gulf of Mexico estuaries harbor diverse fish and decapod crustacean assemblages: A meta-synthesis

Oyster reefs provide habitat for numerous fish and decapod crustacean species that mediate ecosystem functioning and support vibrant fisheries. Recent focus on the restoration of eastern oyster ( Crassostrea virginica) reefs stems from this role as a critical ecosystem engineer. Within the shallow estuaries of the northern Gulf of Mexico (nGoM), the eastern oyster is the dominant reef building organism. This study synthesizes data on fish and decapod crustacean occupancy of oyster reefs across nGoM with the goal of providing management and restoration benchmarks, something that is currently lacking for the region. Relevant data from 23 studies were identified, representing data from all five U.S. nGoM states over the last 28 years. Cumulatively, these studies documented over 120,000 individuals from 115 fish and 41 decapod crustacean species. Densities as high as 2,800 ind m −2 were reported, with individual reef assemblages composed of as many as 52 species. Small, cryptic organisms that occupy interstitial spaces within the reefs, and sampled using trays, were found at an average density of 647 and 20 ind m −2 for decapod crustaceans and fishes, respectively. Both groups of organisms were comprised, on average, of 8 species. Larger-bodied fishes captured adjacent to the reef using gill nets were found at an average density of 6 ind m −2 , which came from 23 species. Decapod crustaceans sampled with gill nets had a much lower average density, <1 ind m −2 , and only contained 2 species. On average, seines captured the greatest number of fish species ( n = 33), which were made up of both facultative residents and transients. These data provide general gear-specific benchmarks, based on values currently found in the region, to assist managers in assessing nekton occupancy of oyster reefs, and assessing trends or changes in status of oyster reef associated nekton support. More explicit reef descriptions (e.g., rugosity, height, area, adjacent habitat) would allow for more precise benchmarks as these factors are important in determining nekton assemblages, and sampling efficiency.

Alabama, Florida, Louisiana, Mississippi, Texas↗

USGS2020

Steps to develop early warning systems and future scenarios of wave-driven flooding along coral reef-lined coasts

Tropical coral reef-lined coasts are exposed to storm wave-driven flooding. In the future, flood events during storms are expected to occur more frequently and to be more severe due to sea-level rise, changes in wind and weather patterns, and the deterioration of coral reefs. Hence, disaster managers and coastal planners are in urgent need of decision-support tools. In the short-term, these tools can be applied in Early Warning Systems (EWS) that can help to prepare for and respond to impending storm-driven flood events. In the long-term, future scenarios of flooding events enable coastal communities and managers to plan and implement adequate risk-reduction strategies. Modeling tools that are used in currently available coastal flood EWS and future scenarios have been developed for open-coast sandy shorelines, which have only limited applicability for coral reef-lined shorelines. The tools need to be able to predict local sea levels, offshore waves, as well as their nearshore transformation over the reefs, and translate this information to onshore flood levels. In addition, future scenarios require long-term projections of coral reef growth, reef composition, and shoreline change. To address these challenges, we have formed the UFORiC (Understanding Flooding of Reef-lined Coasts) working group that outlines its perspectives on data and model requirements to develop EWS for storms and scenarios specific to coral reef-lined coastlines. It reviews the state-of-the-art methods that can currently be incorporated in such systems and provides an outlook on future improvements as new data sources and enhanced methods become available.

Frontiers in Marine Science↗

USGS2003

Thermal exposure of juvenile fall chinook salmon migrating through a lower Snake River Reservoir

Impoundment of the Snake River, Washington, has resulted in high water temperatures and late seaward migration of juvenile fall chinook salmon during summer months. To determine if juvenile fall chinook salmon are exposed to temperatures higher than the upper incipient lethal, we tagged groups of fish with temperature-sensing radio tags and tracked them in Little Goose Reservoir on the Snake River during the summers of 1998 and 1999. Spatial and temporal patterns of the reservoir's thermal environment were described using a bathythermograph. Little Goose Reservoir was generally homothermic, and temperatures selected by fish were typically not significantly different from mean water temperatures. No areas of thermal refugia existed in Little Goose Reservoir. Thermal exposure was most influenced by fish residence time in the reservoir within each year and by temperature differences between years. Current augmentation of Snake River summer flows with cold-water releases from Dworshak Dam in Idaho reduces the thermal exposure of juvenile fall chinook salmon by lowering water temperatures up to 4??C and may therefore increase their survival. Continued flow augmentation using water from Dworshak Reservoir may be the only mechanism to meet the temperature standard for the lower Snake River.

Idaho, Oregon, Washington↗

USGS2015

Mercury in Pacific bluefin tuna (Thunnus orientalis):bioaccumulation and trans-Pacific Ocean migration

Pacific bluefin tuna (Thunnus orientalis) have the largest home range of any tuna species and are well known for the capacity to make transoceanic migrations. We report the measurement of mercury (Hg) concentrations in wild Pacific bluefin tuna (PBFT), the first reported with known size-of-fish and capture location. The results indicate juvenile PBFT that are recently arrived in the California Current from the western Pacific Ocean have significantly higher Hg concentrations in white muscle (0.51 ug/g wet mass, wm) than PBFT of longer California Current residency (0.41 ug/g wm). These new arrivals are also higher in Hg concentration than PBFT in farm pens (0.43 ug/g wm) that were captured on arrival in the California Current and raised in pens on locally derived feed. Analysis by direct Hg analyzer and attention to Hg by tissue type and location on the fish allowed precise comparisons of mercury among wild and captive fish populations. Analysis of migration and nearshore residency, determined through extensive archival tagging, bioaccumulation models, trophic investigations, and potential coastal sources of methylmercury, indicates Hg bioaccumulation is likely greater for PBFT juvenile habitats in the western Pacific Ocean (East China Sea, Yellow Sea) than in the eastern Pacific Ocean (California Current). Differential bioaccumulation may be a trophic effect or reflect methylmercury availability, with potential sources for coastal China (large hypoxic continental shelf receiving discharge of three large rivers, and island-arc volcanism) different from those for coastal Baja California (small continental shelf, no large rivers, spreading-center volcanism).

Canadian Journal of Fisheries and Aquatic Sciences↗

USGS2002

Distribution and transport of suspended particulate matter in Monterey Canyon, California

From August 1993 to August 1994, six moorings that measure current, temperature, salinity, and water clarity were deployed along the axis of Monterey Canyon to study the circulation and transport of water and suspended particulate matter through the canyon system. The moorings occupied three sites that are morphologically different: a narrow transverse section (axis width 900 m) at 1450 m water depth, a wide transverse section at 2837 m, and a third site in the fan valley axis farther offshore at 3223 m that recorded for 3 yr. In addition, CTD/transmissometer casts were conducted within and near the Monterey Canyon during four cruises. Our data show a mainly biogenic, surface turbid layer, a limited intermediate nepheloid layer, and a bottom nepheloid layer. There is a consistent presence of a turbid layer within the canyon at a water depth of about 1500 m. Tidal flow dominates at all sites, but currents above the canyon rim and within the canyon appear to belong to two distinct dynamic systems. Bottom intensification of currents plays an important role in raising the near-bottom shear stress high enough that bottom sediments are often, if not always, resuspended. Mean flow pattern suggests a convergence zone between the narrow and wide site: the near-bed (100 m above bottom where the lowest current meter was located) mean transport is down-canyon at the 1450-m site, while the near-bottom transport at the 2837-m site is up-canyon, at a smaller magnitude. Transport at the 3223-m site is dominantly NNW, cross-canyon, with periods of up-canyon flow over 3 yr. A very high-turbidity event was recorded 100 m above the canyon bottom at the narrow site. The event started very abruptly and lasted more than a week. This event was not detected at either of the deeper sites. A canyon head flushing event is likely the cause. ?? 2002 Elsevier Science B.V. All rights reserved.

Marine Geology↗

USGS2004

Wilderness experience in Rocky Mountain National Park 2002: Report to RMNP

Approximately 250,000 acres of backcountry in Rocky Mountain National Park (RMNP or the Park) may be designated as wilderness use areas in the coming years. Currently, over 3 million people visit RMNP each year; many drive through the park on Trail Ridge Road, camp in designated campgrounds, or hike in front-country areas. However, visitors also report much use of backcountry areas that are not easily accessible by roads or trails. Use of the backcountry is growing at RMNP and is accompanied by changing visitor expectations and preferences for wilderness management. For these reasons it is of great importance for the Park to periodically assess what types of environments and conditions wilderness users seek, to help them facilitate a quality wilderness experience. To assist in this effort, the Political Analysis and Science Assistance [PASA] program / Fort Collins Science Center / U.S. Geological Survey, in close collaboration with personnel and volunteers from RMNP and in cooperation with the Natural Resource Recreation and Tourism [NRRT] Department at CSU, and launched a research effort in the summer of 2002 to investigate visitor numbers, wilderness experiences, and management preferences in the Park. Specifically, the purposes of the research reported here are: (1) To determine what constitutes a wilderness experience; (2) To identify important places, visual features, and sounds essential to a quality wilderness experience and; (3) To determine what aspects may detract from wilderness experience in RMNP. Thus, answers to these questions should provide insight for Park managers about visitors' expectations for wilderness recreation and the conditions they seek for quality wilderness experiences. Ultimately, this information can be used to support wilderness management decisions within RMNP. The social science technique of Visitor Employed Photography [VEP] was used to obtain information from visitors about wilderness experiences. Visitors were selected at random from Park-designated wilderness trails, in proportion to their use, and asked to participate in the survey. Respondents were given single-use, 10-exposure cameras and photo-log diaries to record experiences. A total of 293 cameras were distributed, with a response rate of 87%. Following the development of the photos, a copy of the photos, two pertinent pages from the photo-log, and a follow-up survey were mailed to respondents. Fifty six percent of the follow-up surveys were returned. Findings from the two surveys were analyzed and compared.

Open-File Report↗

USGS2013

Louisiana Barrier Island Comprehensive Monitoring (BICM) Program Summary Report: Data and Analyses 2006 through 2010

The Barrier Island Comprehensive Monitoring (BICM) program was implemented under the Louisiana Coastal Area Science and Technology (LCA S&T) office as a component of the System Wide Assessment and Monitoring (SWAMP) program. The BICM project was developed by the State of Louisiana (Coastal Protection Restoration Authority [CPRA], formerly Department of Natural Resources [DNR]) to complement other Louisiana coastal monitoring programs such as the Coastwide Reference Monitoring System-Wetlands (CRMS-Wetlands) and was a collaborative research effort by CPRA, University of New Orleans (UNO), and the U.S. Geological Survey (USGS). The goal of the BICM program was to provide long-term data on the barrier islands of Louisiana that could be used to plan, design, evaluate, and maintain current and future barrier-island restoration projects. The BICM program used both historical and newly acquired (2006 to 2010) data to assess and monitor changes in the aerial and subaqueous extent of islands, habitat types, sediment texture and geotechnical properties, environmental processes, and vegetation composition. BICM datasets included aerial still and video photography (multiple time series) for shoreline positions, habitat mapping, and land loss; light detection and ranging (lidar) surveys for topographic elevations; single-beam and swath bathymetry; and sediment grab samples. Products produced using BICM data and analyses included (but were not limited to) storm-impact assessments, rate of shoreline and bathymetric change, shoreline-erosion and accretion maps, high-resolution elevation maps, coastal-shoreline and barrier-island habitat-classification maps, and coastal surficial-sediment characterization maps. Discussions in this report summarize the extensive data-collection efforts and present brief interpretive analyses for four coastal Louisiana geographic regions. In addition, several coastal-wide and topical themes were selected that integrate the data and analyses within a broader coastal context: (1) barrier-shoreline evolution driven by rapid relative sea-level rise (RSLR), (2) hurricane impacts to the Chandeleur Islands and likelihood of island recovery, (3) impact of tropical storms on barrier shorelines, (4) Barataria Bay tidal-inlet management, and (5) habitat changes related to RSLR. The final theme addresses potential future goals of the BICM program, including rotational annual to semi-decadal monitoring, proposed new-data collection, how to incorporate technological advances with previous data-collection and monitoring protocols, and standardizing methods and quality-control assessments for continued coastal monitoring and restoration.

Louisiana↗

USGS2014

Flood-inundation maps for the Mississinewa River at Marion, Indiana, 2013

Digital flood-inundation maps for a 9-mile (mi) reach of the Mississinewa River from 0.75 mi upstream from the Pennsylvania Street bridge in Marion, Indiana, to 0.2 mi downstream from State Route 15 were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Mississinewa River at Marion (station number 03326500). Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site. Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the current stage-discharge relation at the Mississinewa River streamgage, in combination with water-surface profiles from historic floods and from the current (2002) flood-insurance study for Grant County, Indiana. The hydraulic model was then used to compute seven water-surface profiles for flood stages at 1-fo (ft) intervals referenced to the streamgage datum and ranging from 10 ft, which is near bankfull, to 16 ft, which is between the water levels associated with the estimated 10- and 2-percent annual exceedance probability floods (floods with recurrence interval between 10 and 50 years) and equals the “major flood stage” as defined by the NWS. The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from light detection and ranging (lidar) data having a 0.98 ft vertical accuracy and 4.9 ft horizontal resolution) to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage and forecasted high-flow stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

Indiana↗

USGS2016

Flood inundation maps for the Wabash River at New Harmony, Indiana

Digital flood-inundation maps for a 3.68-mile reach of the Wabash River extending 1.77 miles upstream and 1.91 miles downstream from streamgage 03378500 at New Harmony, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ , depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Wabash River at New Harmony, Ind. (station 03378500). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/ , which also forecasts flood hydrographs at this site (NHRI3). Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at the Wabash River at New Harmony, Ind., streamgage and the documented high-water marks from the flood of April 27–28, 2013. The calibrated hydraulic model was then used to compute 17 water-surface profiles for flood stages at approximately 1-foot intervals referenced to the streamgage datum and ranging from 10.0 feet, or near bankfull, to 25.4 feet, the highest stage of the stage-discharge rating curve used in the model. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging (lidar) data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each water level. The availability of these maps along with Internet information regarding current stage from the USGS streamgage at Wabash River at New Harmony, Ind., and forecasted stream stages from the NWS will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

Indiana↗

USGS2024

Analysis and review of fishery-dependent data for Hawaiian nearshore noncommercial fisheries

Noncommercial, shore-based fisheries provide economic, social, and cultural services to communities throughout the Hawaiian Islands. The State of Hawai‘i Department of Land and Natural Resources (DLNR), Division of Aquatic Resources (DAR) routinely conducts surveys to monitor noncommercial fisheries such that estimates of fishing effort and catch by gear type can be generated and used to implement more sustainable management practices. DAR executes both the Hawai‘i Marine Recreational Fishery Survey (HMRFS), a nationally standardized survey that focuses on intercepting fishers at access points (i.e., boat ramps) across the main Hawaiian Islands, and a set of roving creel surveys on O‘ahu, Maui Nui, and Kaua‘i that observe and intercept fishers at locations along the shoreline outside of those targeted by HMRFS. The latter set of creel surveys were designed to complement HMRFS by expanding its geographic coverage and thus providing a more representative picture of noncommercial fishing in Hawai‘i. Sustainable management priorities set by DAR rely on the availability of statewide, fishery- dependent data. Thus, we collate information from island-based roving creel surveys into a cohesive Statewide Creel Survey Database. Further, we provide preliminary analyses and describe ways that surveys could be streamlined to improve future data collection, analysis, and utility. In so doing, we synthesize the most detailed information to-date about noncommercial shore-based fisheries of Hawai‘i. The unprecedented spatial and temporal coverage of DAR’s dataset reveals the value of their survey efforts over the last decade to address fishery management needs. Our primary objectives, results, and conclusions are summarized below: 1) Integrate DAR roving creel survey data from different islands into a single Statewide Creel Survey Dataset (Chapter II). We describe the collation of creel survey data from O‘ahu, Maui Nui, and Kaua‘i into a statewide dataset. We also offer ways in which these surveys could be streamlined to meet the needs of managers and decision makers. Briefly, these are to create a statewide strategic plan, standardize the execution of standard operating procedures, centralize the creel survey database and associated metadata, and consider using technology that improves the data pipeline, including transitioning from paper-based to electronic systems for data entry and processing. 2) Assess whether the new Statewide Creel Survey Dataset can provide inputs for length-based stock assessments (Chapter III). Only on Maui were interviews conducted with associated catch data. There was reasonably high taxonomic coverage (42 species from 186 interviews with 310 fishers), but low sample sizes for nearly all species precluded the development of length-based stock assessments. We provide summary statistics from the existing data and briefly discuss how technologies could be used to automate analysis of images of noncommercial catch. 3) Analyze the Statewide Creel Survey Dataset for spatial and temporal patterns in fishing effort (Chapter IV): a. Visualizing noncommercial fishing pressure . We found that fishing effort (mean number of fishers observed per survey event at a site) on O'ahu was over three times greater than that recorded during similar surveys conducted on Maui or Kaua'i. We create maps that display the distribution of angling and spearfishing effort around each of the three islands. b. Factors that predict fishing “hotspots” around Maui . Fishing effort on Maui was associated with areas with more wave power and less parking availability. There were half as many fishers in areas with parking lots than in areas with parking on the road shoulder only. c. Changes in fishing effort during the COVID-19 pandemic . There was no change in fishing effort on O‘ahu during the first year of the pandemic, but there was a 20% decline in year 2 and a 33% decline in year 3, both in comparison to pre-pandemic levels. Pre-pandemic creel survey data were unavailable for Maui and Kaua‘i, but fishing effort on these islands also declined as the pandemic progressed at similar or greater rates than those observed on O‘ahu. 4) Quantify potential bias in survey methods by experimentally deriving fisher detection probabilities of shore-based and drone-based surveys (Chapter V): a. Shore-based surveys . We conducted roving creel surveys for four months at three locations around Hilo Bay, designed to emulate and estimate the efficacy of DAR standard operating procedures. There was high agreement between paired observers in counting fishers, leading to near-perfect detection probabilities of both anglers (94%) and spearfishers (97%), but relatively low agreement and detection probabilities of other fishers (throw net, ‘opihi picking, etc.) (52%). b. Drone-based surveys . We used an unmanned aerial vehicle (UAV; operated by DAR staff) to collect imagery of fishers along the Hilo Bay shoreline. We used still images and video clips (with known fishing activity) to build an online survey that was distributed to DAR and HCFRU personnel, asking them to count and categorize resource users as a snorkeler, spearfisher, angler, or other fisher. Only 40.0% of the responses correctly counted and categorized resource users in the image. Anglers were correctly identified and enumerated in 90.0% of the responses, but the correct response rates of the other three user categories ranged from 67.8% – 79.4%. Snorkelers and anglers tended to be undercounted while spearfishers and other fishers were overcounted. 5) Review the potential for incorporating emerging technologies that will improve, augment, and evolve creel survey data collection, especially for spearfishing (Chapter VI). Within the context of monitoring shore-based noncommercial fishing, we review the use of electronic data entry/processing systems with geospatial and image capabilities, field cameras, drones, smart buoys, citizen science apps, data mining social media, artificial intelligence and machine learning. We highlight several of the challenges and considerations when implementing these technologies into creel surveys and provide a synthesis of options that could be used to better estimate spearfishing. The general conclusion of this assessment is that the DAR roving creel survey program is collecting valuable data that supplement the existing HMRFS efforts. However, there are a number of areas that could be improved to make these efforts a more effective tool for decision-making processes in resource management and conservation: 1) Establishment of clear statewide and island objectives for the Statewide Creel Survey Dataset. Currently, data collection efforts are focused towards addressing a very broad purpose – supplementing the HMRFS data collection efforts. However, the results of the preliminary analyses conducted as part of this project suggest that the data could be used to address other areas of need if these objectives were clearly defined. Further, the design of the creel survey would benefit from greater standardization of survey protocols between islands and an effort to define a) the acceptable margins of error associated with the estimates generated by these data and b) the minimum level of change that the surveys would need to detect to be useful to managers. 2) Centralization of data entry, data quality assessment, and data accessibility. Currently, each DAR office manages data entry, checks the data for errors, and is responsible for managing and storing the data. Instituting a centralized data entry system, particularly an online database that can receive survey data from tablets or smartphones running a standardized data collection application would improve efficiency, reduce data entry errors, and accelerate the availability of data to managers. A substantial amount of time and effort from the project described in this report was devoted to checking the dataset for errors. The development and application of data quality assurance protocols would ensure that the data are reliable and available in a timely fashion to support management decisions. 3) Address lingering questions regarding the efficacy of current survey protocols to capture and characterize the spearfishing component of the noncommercial fishery. The results presented in the report suggest that the current creel survey protocols do a good job detecting spearfishers when present but are not capturing sufficient data about their catch or total effort. There are also questions remaining as to whether the survey times and sites are sufficiently capturing the behavior of spearfishers in Hawai‘i. A more thorough assessment – whether through additional research, alteration of survey design, or review of data by representatives of the spearfishing community – would provide insight on how to use the Statewide Creel Survey Database to inform management of spearfishing. 4) Investigate the integration of technological advancements into the creel survey methods. As priorities and needs are developed and formalized, it would be valuable to consider how various technological advancements might enhance and streamline data collection or open new avenues of inquiry.

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