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At least 307 records · Page 17Linked to original sources
USGS1994

Acoustic mapping as an environmental management tool: I. detection of barrels of low-level radioactive waste, Gulf of the Farallones National Marine Sanctuary, California

The oceans have been and will continue to be disposal sites for a wide variety of waste products. Often these wastes are not dumped at the designated sites or transport occurs during or after dumping, and, subsequent attempts to monitor the effects the waste products have on the environment are inadequate because the actual location of the waste is not known. Acoustic mapping of the seafloor with sidescan sonar is a very effective technique for locating and monitoring dredge-spoil material and other debris. Sidescan sonar provides an acoustic image or sonograph of the sea floor that is similar to a satellite image of the Earth's land surface. In effect sidescan sonar allows the water column to be stripped from the sea floor, thereby providing a clear, unobstructed view of the sea bed. An example of the potential of this technique is summarized herein for the Gulf of the Farallones region. More than 47 800 drums (55 gallon) and other containers of low-level radioactive waste were dumped on the continental margin offshore the San Francisco Bay between 1946 and 1970. These drums now litter a large area (1200 km 2 ) of the sea floor within the Gulf of the Farallones National Marine Sanctuary (GFNMS). The exact location of the drums and the potential hazard the drums pose to the environment are unknown. To evaluate the risk, samples of the sediment, biota and water must be collected near and distant from the concentrations of barrels. To do this the exact location of the barrels must be known prior to sampling. The USGS, through a cooperative research agreement with GFNMS, used sidescan sonar to map two areas within the sanctuary. Total sea-floor coverage was obtained and computer-processed sonographic mosaics were constructed on board ship. Many small nongeologic targets were distributed throughout the survey areas that covered about 70 km 2 on the shelf and 120 km 2 on the slope. Analysis of the sidescan data suggests that the targets are 55-gallon drums. This interpretation was confirmed at one site with an underwater video and 35-mm camera system. Data were collected with both a 30-kHz and a 120-kHz sidescan system within a 15-km 2 area on the shelf. We found that the barrels were more easily detected with the mid-range 30-kHz system than with the higher resolution 120-kHz system. Maps of barrel distribution derived from the sonographs are being used to design sampling schemes to evaluate the risk that the radioactivity may have on the biota and environment.

California↗
USGS1993

Geological and technological assessment of artificial reef sites, Louisiana outer continental shelf

This paper describes the general procedures used to select sites for obsolete oil and gas platforms as artificial reefs on the Louisiana outer continental shelf (OCS). The methods employed incorporate six basic steps designed to resolve multiple-use conflicts that might otherwise arise with daily industry and commercial fishery operations, and to identify and assess both geological and technological constraints that could affect placement of the structures. These steps include: (1) exclusion mapping; (2) establishment of artificial reef planning areas; (3) database compilation; (4) assessment and interpretation of database; (5) mapping of geological and man-made features within each proposed reef site; and (6) site selection. Nautical charts, bathymetric maps, and offshore oil and gas maps were used for exclusion mapping, and to select nine regional planning areas. Pipeline maps were acquired from federal agencies and private industry to determine their general locations within each planning area, and to establish exclusion fairways along each pipeline route. Approximately 1600 line kilometers of high-resolution geophysical data collected by federal agencies and private industry was acquired for the nine planning areas. These data were interpreted to determine the nature and extent of near-surface geologic features that could affect placement of the structures. Seismic reflection patterns were also characterized to evaluate near-bottom sedimentation processes in the vicinity of each reef site. Geotechnical borings were used to determine the lithological and physical properties of the sediment, and for correlation with the geophysical data. Since 1987, five sites containing 10 obsolete production platforms have been selected on the Louisiana OCS using these procedures. Industry participants have realized a total savings of approximately US $1 500 000 in salvaging costs by converting these structures into artificial reefs. ?? 1993.

Ocean and Coastal Management↗
USGS2015

The modelling and assessment of whale-watching impacts

In recent years there has been significant interest in modelling cumulative effects and the population consequences of individual changes in cetacean behaviour and physiology due to disturbance. One potential source of disturbance that has garnered particular interest is whale-watching. Though perceived as ‘green’ or eco-friendly tourism, there is evidence that whale-watching can result in statistically significant and biologically meaningful changes in cetacean behaviour, raising the question whether whale-watching is in fact a long term sustainable activity. However, an assessment of the impacts of whale-watching on cetaceans requires an understanding of the potential behavioural and physiological effects, data to effectively address the question and suitable modelling techniques. Here, we review the current state of knowledge on the viability of long-term whale-watching, as well as logistical limitations and potential opportunities. We conclude that an integrated, coordinated approach will be needed to further understanding of the possible effects of whale-watching on cetaceans.

Ocean and Coastal Management↗
USGS2018

Temporal shift of sea turtle nest sites in an eroding barrier island beach

Shoreline changes affect functionality of a sandy beach as a wildlife habitat and coastal erosion is among the primary causes of the changes. We examined temporal shifts in locations where loggerheads placed nests in relation to coastal erosion along a barrier island beach in the northern Gulf of Mexico. We first confirmed consistency in long-term (1855–2001), short-term (1976–2001), and more recent (2002–2012) shoreline change rates in two adjacent beach sections, one historically eroding (west beach) and the other accreting (east beach). The mean annual shoreline change rate in the two sections was significantly different in all time periods. The recent (1998–2012) mean change rate was −10.9 ± 9.9 m/year in the west beach and −2.8 ± 4.9 m/year in the east beach, which resulted in the loss of about 70% and 30% of area in the west and east beaches, respectively. Loggerheads nested significantly closer to the vegetation line in 2012 than in 2002 in the west beach but the difference between the two time periods was not significant in the east beach. However, the distance from nests to the vegetation line from 2002 to 2014 was significantly reduced annually in both beaches; on average, loggerheads nested closer to the vegetation line by 9 m/year in the west beach and 5.8 m/year in the east beach. The observed shoreline change rate and corresponding shift of nest placement sites, combined with the forecasted future beach loss, highlighted the importance of addressing the issue of beach erosion to conserve sandy beach habitats.

Florida↗
USGS2018

Conservation and restoration of mangroves: Global status, perspectives, and prognosis

Mangrove forests provide critical services around the globe to both human populations and the ecosystems they occupy. However, losses of mangrove habitat of more than 50% have been recorded in some parts of the world, and these losses are largely attributable to human activities. The importance of mangroves and the threats to their persistence have long been recognized, leading to actions taken locally, by national governments, and through international agreements for their protection. In this review, we explore the status of mangrove forests as well as efforts to protect them. We examine threats to the persistence of mangroves, consequences, and potential solutions for effective conservation. We present case studies from disparate regions of the world, showing that the integration of human livelihood needs in a manner that balances conservation goals can present solutions that could lead to long-term sustainability of mangrove forests throughout the world.

Ocean and Coastal Management↗
USGS2018

Spatial distribution of estuarine diamond-backed terrapins (Malaclemys terrapin) and risk analysis from commercial blue crab (Callinectes sapidus) trapping at the Savannah Coastal Refuges Complex, USA

The diamond-backed terrapin (Malaclemys terrapin) is a small estuarine turtle distributed along the Atlantic and Gulf Coasts of the USA. Terrapin populations are declining throughout their range and one of the main causes is mortality by drowning as bycatch in commercially-fished blue crab (Callinetes sapidus) traps (aka pots). We conducted head counts of terrapins and documented the distribution and number of crab pots on the Savannah Coastal Refuges Complex in southeast Georgia, USA. Using an index for representing relative degree of crabbing pressure, we conducted a spatial risk analysis for each of the four refuges surveyed. We fit a series of generalized linear mixed effect models to test hypotheses about the scale (creek scale vs. refuge/island scale) at which terrapin relative abundances respond to crab trapping. Several creeks were found to be at high risk of terrapin mortality from crab pots. Areas with low terrapin head counts may be a result of past crab pot mortality. The best model relating terrapin counts to crab trapping revealed a negative effect of crab pots calculated at the refuge/island scale and included a positive association between cloud cover and terrapin counts. The estimated effect of crab pot number at the refuge/island scale suggests that an increase in crab pot density of one pot per creek is associated with a 74.6% decline in terrapin head counts, underscoring the sensitivity of terrapin populations to crab pot mortality. Mitigation of this mortality factor via redesigned crab traps with bycatch reduction devices may be necessary to maintain healthy terrapin populations on the refuges.

Georgia↗
USGS2020

Pulse sediment event does not impact the metabolism of a mixed coral reef community

Sedimentation can bury corals, cause physical abrasion, and alter both spectral intensity and quality; however, few studies have quantified the effects of sedimentation on coral reef metabolism in the context of episodic sedimentation events. Here, we present the first study to measure coral community metabolism - calcification and photosynthesis - in a manipulative mesocosm experiment simulating a pulse sediment event. We exposed a mixed benthic community composed of 75% live carbonate rubble cover and 25% Montipora capitata coral cover to an approximately 275 mg cm−1 (sediment accumulation) acute pulse sediment loading event. No differences were found in net calcification or net photosynthesis between the control and treated mesocosms 48 h and 25 d following exposure to pulse sediment input. Results from this community experiment indicate the ability of Montipora capitata, a common reef coral, to persist under these acute sediment levels, demonstrating resistance to episodic sediment events.

Hawaii↗
USGS2020

Quantifying harvestable fish and crustacean production and associated economic values provided by oyster reefs

Quantifying ecosystem services can provide information to justify conservation and restoration decisions so as to allocate limited resources effectively. Consequently, decision makers and public typically ask for simple and understandable information with confidence regarding the availability of the services and the probable economic value. Here, we compiled published information on density enhancement and species life-history information to quantify fish and crustacean production and its uncertainty associated with the current extent of oyster ( Crassostrea virginica ) reefs in Mobile Bay, Alabama. We applied Alabama fishing size limits as a cutoff to exclude the production of non-harvestable size individuals. Fishery landing (2005–2015) and Willingness-To-Pay information were used to quantify the economic benefit of the harvestable production enhancement (commercial and recreational production). Sixteen species were found to be production-enhanced in the bay with a mean of 354 ± 182 g m −2 year −1 , of which 170 ± 112 g m −2 year −1 was economically quantifiable based on their harvestable production and landing information. The mean economic value was $509,000 year −1 in direct economic value for commercial fishers and $19.59 million year −1 estimated by the willingnesstopay value from recreational anglers. The results demonstrated a substantial positive economic benefit of ecosystem services from oyster reefs associated with fishery production in Mobile Bay, Alabama. The method could be applied elsewhere to estimate the economic return from the investment of conserving and restoring of similar structured habitats.

Alabama↗
USGS2022

Predicted sea-level rise-driven biogeomorphological changes on Fire Island, New York: Implications for people and plovers

Forecasting biogeomorphological conditions for barrier islands is critical for informing sea-level rise (SLR) planning, including management of coastal development and ecosystems. We combined five probabilistic models to predict SLR-driven changes and their implications on Fire Island, New York, by 2050. We predicted barrier island biogeomorphological conditions, dynamic landcover response, piping plover ( Charadrius melodus ) habitat availability, and probability of storm overwash under three scenarios of shoreline change (SLC) and compared results to observed 2014/2015 conditions. Scenarios assumed increasing rates of mean SLC from 0 to 4.71 m erosion per year. We observed uncertainty in several morphological predictions (e.g., beach width, dune height), suggesting decreasing confidence that Fire Island will evolve in response to SLR as it has in the past. Where most likely conditions could be determined, models predicted that Fire Island would become flatter, narrower, and more overwash-prone with increasing rates of SLC. Beach ecosystems were predicted to respond dynamically to SLR and migrate with the shoreline, while marshes lost the most area of any landcover type compared to 2014/2015 conditions. Such morphological changes may lead to increased flooding or breaching with coastal storms. However—although modest declines in piping plover habitat were observed with SLC—the dynamic response of beaches, flatter topography, and increased likelihood of overwash suggest storms could promote suitable conditions for nesting piping plovers above what our geomorphology models predict. Therefore, Fire Island may offer a conservation opportunity for coastal species that rely on early successional beach environments if natural overwash processes are encouraged.

New York↗
USGS2016

Evaluation of dynamic coastal response to sea-level rise modifies inundation likelihood

Sea-level rise (SLR) poses a range of threats to natural and built environments1, 2, making assessments of SLR-induced hazards essential for informed decision making3. We develop a probabilistic model that evaluates the likelihood that an area will inundate (flood) or dynamically respond (adapt) to SLR. The broad-area applicability of the approach is demonstrated by producing 30 × 30 m resolution predictions for more than 38,000 km2 of diverse coastal landscape in the northeastern United States. Probabilistic SLR projections, coastal elevation and vertical land movement are used to estimate likely future inundation levels. Then, conditioned on future inundation levels and the current land-cover type, we evaluate the likelihood of dynamic response versus inundation. We find that nearly 70% of this coastal landscape has some capacity to respond dynamically to SLR, and we show that inundation models over-predict land likely to submerge. This approach is well suited to guiding coastal resource management decisions that weigh future SLR impacts and uncertainty against ecological targets and economic constraints.

Nature Climate Change↗
USGS2004

Vulnerability of port and harbor communities to earthquake and tsunami hazards: The use of GIS in community hazard planning

Abstract Earthquakes and tsunamis pose significant threats to Pacific Northwest coastal port and harbor communities. Developing holistic mitigation and preparedness strategies to reduce the potential for loss of life and property damage requires community-wide vulnerability assessments that transcend traditional site-specific analyses. The ability of a geographic information system (GIS) to integrate natural, socioeconomic, and hazards information makes it an ideal assessment tool to support community hazard planning efforts. This article summarizes how GIS was used to assess the vulnerability of an Oregon port and harbor community to earthquake and tsunami hazards, as part of a larger risk-reduction planning initiative. The primary purposes of the GIS were to highlight community vulnerability issues and to identify areas that both are susceptible to hazards and contain valued port and harbor community resources. Results of the GIS analyses can help decision makers with limited mitigation resources set priorities for increasing community resiliency to natural hazards.

Coastal Management↗
USGS2014

Indigenous community health and climate change: integrating biophysical and social science indicators

This article describes a pilot study evaluating the sensitivity of Indigenous community health to climate change impacts on Salish Sea shorelines (Washington State, United States and British Columbia, Canada). Current climate change assessments omit key community health concerns, which are vital to successful adaptation plans, particularly for Indigenous communities. Descriptive scaling techniques, employed in facilitated workshops with two Indigenous communities, tested the efficacy of ranking six key indicators of community health in relation to projected impacts to shellfish habitat and shoreline archaeological sites stemming from changes in the biophysical environment. Findings demonstrate that: when shellfish habitat and archaeological resources are impacted, so is Indigenous community health; not all community health indicators are equally impacted; and, the community health indicators of highest concern are not necessarily the same indicators most likely to be impacted. Based on the findings and feedback from community participants, exploratory trials were successful; Indigenous-specific health indicators may be useful to Indigenous communities who are assessing climate change sensitivities and creating adaptation plans.

British Columbia;Washington↗
USGS2019

Coastal armoring and sea turtles: Beachfront homeowners’ opinions and intent

Florida’s dynamic beach-dune ecosystem and the structures built along the shore face threats from coastal (or shoreline) erosion, sea level rise, and inadequate regulatory protection efforts. In light of these threats, private property owners are choosing to install coastal armoring on their property to protect upland structures which can negatively impact sea turtles and their nesting habitat. Coastal armoring can significantly degrade the beach-dune ecosystem which serves as a vital economic and recreational resource and as crucial habitat for threatened or endangered sea turtle species, nesting shorebirds, and other endemic species. This study explored both Florida coastal property owner’s opinions of coastal armoring, and its impact on sea turtles and their nesting habitat. A quantitative survey was administered to beachfront single-family property owners that live within a mile of a protected section of beach (e.g, state park, preserve, wildlife refuge). In total, 373 of 1,274 distributed surveys were returned and analyzed. The presence of a neighbor with coastal armoring was the most influential factor on a property owner intending to, or already having installed coastal armoring. Additionally, higher assessed property values and lower levels of education were also associated with intent to armor, or current presence of coastal armoring on a parcel.

Florida↗
USGS2026

From uncertainty to co-production: Structural and systemic barriers to salmon recovery in Puget Sound

This case study examines barriers to implementing “H-Integrated” salmon recovery strategies—efforts that coordinate habitat, hatchery, harvest, and hydropower actions—in Puget Sound. Based on a focus group with Tribal, State, Federal, and nonprofit practitioners, we identified five interconnected constraints: data gaps , modeling frameworks , decision-making under uncertainty , limited organizational capacity , and collaboration across silos . These were embedded within a sixth cross-cutting constraint: structural and systemic barriers , exemplified by complicated institutional dynamics and differences in how expertise is recognized across organizations. Participants emphasized that these challenges are closely connected, making it harder for groups to plan together, adapt to change, or try new approaches. Many of these challenges reflect not only technical limitations, but also stem from contrasting perspectives on data collection and decision authority, as well as the complex histories that have shaped relationships among agencies, organizations, and Tribal Nations. We interpret these dynamics through the lenses of situated knowledge and epistemological pluralism and suggest that effective knowledge co-production can bridge these gaps and strengthen collaborative problem-solving, innovation, and risk-taking. Participants emphasized that, along with modeling tools that reflect the realities of on-the-ground decision-making, H-Integration depends on institutional support for collaborative monitoring and trust-building. In practice, this means developing processes that integrate different perspectives and treating co-production as an ongoing institutional commitment.

Washington↗
USGS2026

Cultural benefits knowledge and social learning in Elwha River dam removal and ecosystem decision-making

In a retrospective case study of the seminal Elwha River dam removal in Washington State, USA, we explore pathways through which ecosystem services (ES) knowledge can inform environmental decision-making. We specifically investigate how knowledge of cultural benefits linked to the Elwha River ecosystem was made available. Through interviews and historical document review we identify diverse forms of cultural benefits knowledge (i.e., how individuals or groups know the contributions of an ecosystem to their identities, experiences, and capabilities), including both knowledge in the form of practices – embodied or enacted forms of knowledge, and knowledge in the form of products – quantitative or written documentation. Recognizing and learning from the diverse forms in which benefits knowledges are conveyed can support more accurate and equitable consideration of the diverse values, well-beings, and human-nature relationships linked to ecosystems. With this case study, we illuminate pathways for meaningful consideration of multiple knowledge forms, and the plural ecosystem values they convey, with relevance for environmental decision processes in the Puget Sound and beyond.

Washington↗
USGS2016

Smartphone-based distributed data collection enables rapid assessment of shorebird habitat suitability

Understanding and managing dynamic coastal landscapes for beach-dependent species requires biological and geological data across the range of relevant environments and habitats. It is difficult to acquire such information; data often have limited focus due to resource constraints, are collected by non-specialists, or lack observational uniformity. We developed an open-source smartphone application called iPlover that addresses these difficulties in collecting biogeomorphic information at piping plover ( Charadrius melodus ) nest sites on coastal beaches. This paper describes iPlover development and evaluates data quality and utility following two years of collection ( n = 1799 data points over 1500 km of coast between Maine and North Carolina, USA). We found strong agreement between field user and expert assessments and high model skill when data were used for habitat suitability prediction. Methods used here to develop and deploy a distributed data collection system have broad applicability to interdisciplinary environmental monitoring and modeling.

PLoS ONE↗
USGS2003

Status and interconnections of selected environmental issues in the global coastal zones

This study focuses on assessing the state of population distribution, land cover distribution, biodiversity hotspots, and protected areas in global coastal zones. The coastal zone is defined as land within 100 km of the coastline. This study attempts to answer such questions as: how crowded are the coastal zones, what is the pattern of land cover distribution in these areas, how much of these areas are designated as protected areas, what is the state of the biodiversity hotspots, and what are the interconnections between people and coastal environment. This study uses globally consistent and comprehensive geospatial datasets based on remote sensing and other sources. The application of Geographic Information System (GIS) layering methods and consistent datasets has made it possible to identify and quantify selected coastal zones environmental issues and their interconnections. It is expected that such information provide a scientific basis for global coastal zones management and assist in policy formulations at the national and international levels.

Ambio↗