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At least 469 records · Page 26Linked to original sources
USGS2021

Genetic variation in sea otters (Enhydra lutris) from the North Pacific with relevance to the threatened Southwest Alaska Distinct Population Segment

For the sea otter ( Enhydra lutris ), genetic population structure is an area of research that has not received significant attention, especially in Southwest Alaska where that distinct population segment has been listed as threatened since 2005 pursuant to the U.S. Endangered Species Act. In this study, 501 samples from 14 locations from Prince William Sound, Alaska to the Commander Islands in Russia were analyzed for variation at 13 microsatellite loci. Our results indicate a high degree of genetic divergence among the 14 locations ( F ST = 0.120) with gene flow conforming to the isolation by distance (IBD) model ( r 2 = 0.491, p < .05). The 14 sampling locations formed six geographic associations in clustering and ordination analyses that likely correspond to remnant population lineages: (1) Southcentral Alaska, (2) Kodiak and North Alaska Peninsula, (3) South Alaska Peninsula and Bristol Bay, (4) Eastern Aleutian, (5) Western Aleutian, and (6) the Commander Islands. Except for South Alaska Peninsula and Bristol Bay, these clusters closely agree with previously defined stock and management unit boundaries. Our results reveal significant genetic population structure and are generally congruent with current management strategies for the threatened Southwest Alaska distinct population segment.

Alaska↗
USGS2023

Effects of feeding and habitat on resting metabolic rates of the Pacific walrus

Arctic marine mammals live in a rapidly changing environment due to the amplified effects of global warming. Pacific walruses ( Odobenus rosmarus divergens ) have responded to declines in Arctic sea-ice extent by increasingly hauling out on land farther from their benthic foraging habitat. Energy models can be useful for better understanding the potential implications of changes in behavior on body condition and reproduction but require behavior-specific metabolic rates. Here we measured the resting metabolic rates (RMR) of three captive, adult female Pacific walruses through breath-by-breath respirometry when fed and fasted resting out of water (sitting and lying down) and while fed resting in water. RMR in and out of water were positively related with pretrial energy intake when not fasted and 25% higher than RMR when walruses were fasted and out of water. Overall, RMR was higher than previously estimated for this species. Fasting RMR out of water was only 25% lower than subsurface swimming metabolic rates suggestive of relatively efficient swimming in adult females. Our results identify the importance of considering feeding status and species-specific differences in affecting metabolic costs. Further research is needed to better understand potential energetic costs of thermoregulation at temperatures experienced by wild walruses.

Valencia↗
USGS2026

Quantifying southern sea otter (Enhydra lutris nereis) reactions to a quadcopter drone in central California

Drones are useful for wildlife research and management, but they can cause disturbance and harassment to wildlife. Sea otters ( Enhydra lutris ) are candidates for drone-based observation and monitoring but are vulnerable to disturbance. No studies have evaluated drone effects on sea otter behavior, but based on prior disturbance studies, we hypothesized: (1) sea otters would exhibit behaviors indicating higher reactivity in the presence of drones than when drones were absent and (2) drone disturbance to sea otters would be greater when drones were closer. At two sites in Monterey Bay, CA, we conducted 37 observational sessions, recording behavior codes for focal sea otters during a baseline (no drone) period and three consecutive drone flights. Data were analyzed using ANOVA and ordinal logistic regression models. At both locations, focal sea otters had higher behavior codes during drone trials compared to baseline, and behavior codes increased with descending drone altitude. Pup presence, group size, flight trial number, and gull presence were significant covariables. We calculated multipliers to predict drone-mediated behavioral responses at a range of drone altitudes. Our findings can inform best practices for a variety of uses of drones around sea otters, including population monitoring, oil spill response, and drone photography/videography.

California↗
USGS2023

Decision science as a framework for combining geomorphological and ecological modeling for the management of coastal systems

The loss of ecosystem services due to climate change and coastal development is projected to have significant impacts on local economies and conservation of natural resources. Consequently, there has been an increase in coastal management activities such as living shorelines, oyster reef restoration, marsh restoration, beach and dune nourishment, and revegetation projects. Coastal management decisions are complex and include challenging trade-offs. Decision science offers a useful framework to address such complex problems. Here, we provide a synthesis about how decision science can help to integrate research from multiple disciplines (physical and life sciences) with management of coastal and marine systems. Specifically, we discuss the importance of considering concepts and techniques from ecology, coastal geology, geomorphology, climate science, oceanography, and decision analysis when developing conservation plans for coastal restoration. We illustrate the process with several coastal restoration studies. Our capstone example is based on a recent barrier island restoration assessment project at Dauphin Island, Alabama, which included the development of geomorphological and ecological models. We show how decision science can be used as a framework to combine geomorphological and ecological modeling to help inform management decisions while considering uncertainty about system changes and risk tolerance. We also build on our examples through a review of recently developed techniques for spatial conservation planning for land acquisition decisions and the application of adaptive management for sequential decisions.

Alabama↗
USGS2008

EAARL topography-Colonial National Historical Park

These Lidar-derived topography maps were produced as a collaborative effort between the U.S. Geological Survey (USGS) Coastal and Marine Geology Program, Florida Integrated Science Center (FISC) St. Petersburg, the National Park Service (NPS) Inventory and Monitoring Program, Northeast Coastal and Barrier Network, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility. One objective of this research is to create techniques to survey coral reefs, barrier islands, and various nearshore coastal environments for the purposes of geomorphic change studies, habitat mapping, ecological monitoring, change detection, and event assessment. As part of this project, data from an innovative instrument under development at the NASA Wallops Flight Facility, the NASA Experimental Airborne Advanced Research Lidar (EAARL) are being used. This sensor has the potential to make significant contributions in this realm for measuring subaerial and submarine topography wthin cross-environment surveys. High spectral resolution, water-column correction, and low costs were found to be key factors in providing accurate and affordable imagery to coastal resource managers.

Virginia↗
USGS2018

Integrated observations and informatics improve understanding of changing marine ecosystems

Marine ecosystems have numerous benefits for human societies around the world and many policy initiatives now seek to maintain the health of these ecosystems. To enable wise decisions, up to date and accurate information on marine species and the state of the environment they live in is required. Moreover, this information needs to be openly accessible to build indicators and conduct timely assessments that decision makers can use. The questions and problems being addressed demand global-scale investigations, transdisciplinary science, and mechanisms to integrate and distribute data that otherwise would appear to be disparate. Essential Ocean Variables (EOVs) and marine Essential Biodiversity Variables (EBVs), conceptualized by the Global Ocean Observing System (GOOS) and the Marine Biodiversity Observation Network (MBON), respectively, guide observation of the ocean. Additionally, significant progress has been made to coordinate efforts between existing programs, such as the GOOS, MBON, and Ocean Biogeographic Information System collaboration agreement. Globally and nationally relevant indicators and assessments require increased sharing of data and analytical methods, sustained long-term and large-scale observations, and resources to dedicated to these tasks. We propose a vision and key tenets as a guiding framework for building a global integrated system for understanding marine biological diversity and processes to address policy and resource management needs. This framework includes: using EOVs and EBVs and implementing the guiding principles of Findable, Accessible, Interoperable, Reusable (FAIR) data and action ecology. In doing so, we can encourage relevant, rapid, and integrative scientific advancement that can be implemented by decision makers to maintain marine ecosystem health.

Frontiers in Marine Science↗
USGS2021

Can identifying discrete behavioral groups with individual-based acoustic telemetry advance the understanding of fish distribution patterns?

Identifying patterns of organismal distribution can provide valuable insights for basic and applied marine and coastal ecology because understanding where animals are located is foundational to both research and science-based conservation. Understanding variation in distributional patterns can lead to a better assessment of ecological drivers and an improved ability to predict consequences of natural and altered relationships. Here, our purpose is to explore if quantifying coexisting groups of individual fish predators advances our understanding of field distribution patterns. Toward this end, we quantified locations of 59 acoustically tagged striped bass ( Morone saxatilis) within a 26-stationary unit telemetry receiver array in Plum Island Estuary (PIE), MA, United States. We then used cluster analyses on spatial and temporal-spatial metrics from this dataset to (1) assess if distinct groups of individuals coexisted, (2) quantify group characteristics, and (3) test associations between groups and distribution (e.g., physical site type and region). Based on multiple lines of evidence, we identified four groups of striped bass with different space use patterns that persisted across seasons (summer and fall). Similar-sized striped bass clustered at spatial and temporal scales at which individuals within distinct groups could, and did, physically overlap. In addition, distributional groups were linked to components of physical site type and region suggesting that discrete groups of individuals can interact differently with the environment within the same ecological system. The identification of these distinct groups of individuals creates a baseline from which to explore further ecological implications of grouping behavior for research and conservation in geographically large, temporally dynamic, and spatially heterogeneous marine and coastal environments.

Massachusetts↗
USGS2022

Estimating the pelagic ocean’s benefits to humanity can enhance ocean governance

The human footprint on the global ocean is ever-increasing, particularly with new ways to grow food in the ocean, new technologies in marine energy production as a way to resolve climate change, and transport and commerce expanding across the ocean. Yet, human activities in the ocean have long been managed using a sectoral approach (e.g., fisheries, biodiversity protection, energy production, shipping) rather than a holistic integration of sector interactions, trade-offs, costs, and benefits. Coordination across sectors is now more critical than ever, not only because of the expanding human footprint but also because of climate change impacts on the ocean. Sustainable global ocean use can support the Blue Economy while also reversing negative climate impacts on the ocean. Advancements in science and technology, along with increasing momentum on global commitments to sound ocean governance, and science diplomacy internationally can support sustainable ocean use with accurate and timely information about the status and trends in the ocean’s ecosystem services (benefits) to society. Near-real time information about ecosystem services’ dynamics is critical to policymaking for a sustainable Blue Economy that works for nature and people in an ever-changing ocean. Here, we propose seven principles for ecosystem service assessments, essentially to international science diplomacy, for consideration by global marine policy communities.

Marine Policy↗
USGS1990

A quantitative micropaleontologic method for shallow marine peleoclimatology: Application to Pliocene deposits of the western North Atlantic Ocean

A transfer function was developed to estimate summer and winter paleotemperatures for arctic to tropical regions of the western North Atlantic Ocean using fossil ostracode assemblages. Q-mode factor analysis was run on ostracode assemblages from 100 modern bottom sediment samples from continental shelves of North America, Greenland and the Caribbean using 59 ostracode taxa. Seven factors accounting for 80% of the variance define assemblages that correspond to frigid, subfrigid, cold temperate, mild temperate, warm temperate, subtropical and tropical climatic zones. Multiple regression of the factor matrix against observed February and August bottom temperatures yielded an astracode transfer function with an accuracy of about ??2??C. The transfer function was used to reconstruct middle Pliocene (3.5-3.0 Ma) shallow marine climates of the western North Atlantic during the marine transgression that deposited the Yorktown Formation (Virginia and North Carolina), the Duplin Formation (South and North Carolina) and the Pinecrest beds (Florida). Middle Pliocene paleowater temperatures in Virginia averaged 19??C in August and 13.5??C in February, about 5??C to 8??C warmer than at comparable depths off Virginia today. August and February water temperatures in North Carolina were 23??C and 13.4??C, in South Carolina about 23??C and 13.5??C and in southern Florida about 24.6??C and 15.4??C. Marine climates north of 35??N were warmer than today; south of 35??N, they were about the same or slightly cooler. Thermal gradients along the coast were generally not as steep as they are today. The North Atlantic transfer function can be applied to other shallow marine Pliocene and Pleistocene deposits of eastern North America. ?? 1990 Elsevier Science Publishers B.V.

Marine Micropaleontology↗
USGS2021

Modeling at-sea density of marine birds to support renewable energy planning on the Pacific outer continental shelf of the contiguous United States

This report describes the at-sea spatial distributions of marine birds in Pacific OCS waters off the contiguous U.S. (Figure 1.1) to inform marine spatial planning in the region. The goal was to estimate long-term average spatial distributions for marine bird species using all available science-quality transect survey data and numerous bathymetric, oceanographic, and atmospheric predictor variables. We developed seasonal habitat-based spatial models of the at-sea distribution for 33 individual species and 13 taxonomic groups of marine birds throughout the study region. A statistical modeling framework was used to estimate numerical relationships between bird sighting data (i.e., standardized counts) and a range of temporal (e.g., Pacific Decadal Oscillation [PDO] index), spatially static (e.g., depth), and spatially dynamic (e.g., sea surface chlorophyll-a concentration) environmental variables. The estimated relationships were then used to predict spatially explicit long-term average density (individuals per km 2 ) throughout the study area for each species/group in each of four seasons. Bird sighting data came from multiple scientific survey programs and consisted of at-sea counts of birds collected between 1980 and 2017 using boat-based and fixed-wing aerial transect survey methods. Spatial environmental variables were derived from remote sensing satellite data and an ocean dynamics model.

California, Oregon, Washington↗
USGS1958

The solusphere - its inferences and study

Water is a fundamental geologic agent active in rock decomposition, erosion, and synthesis. Solutes in water are of particular interest to geochemists as sources of raw material for synthesis or as products of decomposition. When geochemical studies move from the laboratory into natural environment many variables relating to solute hydrology must be considered. As a focal point there has been designed a graphical representation of solute hydrology, the solusphere, which embodies the concepts of land-water occurrence and movement on which are superimposed geologic, biologic, physical, chemical, and cultural processes affecting solutes. The solusphere is demonstrated by passing an imaginary plane through the centre of the earth. This plane intercepts concentric zones designated as rock flowage, saturation, aeration, surface activity, and atmosphere. Transport processes carry solutes within and between zones without alteration or conversion. However, whether stationary or in motion, the water's solute character is constantly subject to (1) alteration processes that change concentration by addition or subtraction of solutes or solvent without loss of solute identities, and (2) conversion processes that change the chemical state and form of solutes. The geochemist is concerned with specific conversion processes, but he also must consider transport, alteration, and other conversion processes that are continually modifying the materials with which he is dealing in nature. The solusphere is an attempt to organize processes affecting the chemical quality of land waters into a unified field of science much like the field of marine chemistry.

Geochimica et Cosmochimica Acta↗
USGS2011

Lidar vegetation mapping in national parks: Gulf Coast Network

Airborne lidar (Light Detection and Ranging) is an active remote sensing technique used to collect accurate elevation data over large areas. Lidar provides an extremely high level of regional topographic detail, which makes this technology an essential component of U.S. Geological Survey (USGS) science strategy. The USGS Coastal and Marine Geology Program (CMGP) has collaborated with the National Aeronautics and Space Administration (NASA) and the National Park Service (NPS) to acquire dense topographic lidar data in a variety of coastal environments.

Louisiana↗
USGS2015

Data categories for marine planning

The U.S. National Ocean Policy calls for a science- and ecosystem-based approach to comprehensive planning and management of human activities and their impacts on America&rsquo;s oceans. The Ocean Community in Data.gov is an outcome of 2010&ndash;2011 work by an interagency working group charged with designing a national information management system to support ocean planning. Within the working group, a smaller team developed a list of the data categories specifically relevant to marine planning. This set of categories is an important consensus statement of the breadth of information types required for ocean planning from a national, multidisciplinary perspective. Although the categories were described in a working document in 2011, they have not yet been fully implemented explicitly in online services or geospatial metadata, in part because authoritative definitions were not created formally. This document describes the purpose of the data categories, provides definitions, and identifies relations among the categories and between the categories and external standards. It is intended to be used by ocean data providers, managers, and users in order to provide a transparent and consistent framework for organizing and describing complex information about marine ecosystems and their connections to humans.

Open-File Report↗
USGS2026

Agency approach to allocation of human capital and program composition for human-marine mammal interaction management in the United States

Introduction: Marine mammals have served important and diverse roles throughout human history. Once exploited to near extinction, many species in the United States (U.S.) have recovered dramatically under the Marine Mammal Protection Act (MMPA). The U.S. National Marine Fisheries Service (NMFS) has jurisdiction to administer the MMPA for cetaceans and most pinnipeds. While most take is now prohibited, NMFS still dedicates significant time and resources to protecting and conserving marine mammals. As human populations continue to grow and exploit marine environments, opportunities for human-marine mammal interactions (HMMI) have increased. Resources may fail to keep up with growing needs for conservation investments, so that many agencies struggle to adequately meet social and legal requirements. Methods: This study evaluated NMFS’ approach to addressing HMMI through a mixed-methods (semi-structured interviews, quantitative questionnaire, and facilitated workshops) expert elicitation analysis of resource allocation (i.e., staff time) and priorities of NMFS Science Center (SC) and Regional Office (RO) staff across five geographic regions to understand how employee time is allocated, the degree to which employee time allocation is aligned with self-reported job descriptions, and employee perceptions of actions or investments which would improve their ability to mitigate HMMI. Results and Discussion: SC staff reported spending more time on Biological and Administrative tasks , while RO staff allocated more time to Policy, Social science , and Outreach tasks . SC employees spent less time on Biological tasks than specified by their perceived job descriptions, suggesting resource constraints. Participants identified Biological research and monitoring as top priorities, followed by Policy tasks . Identified actions included increasing research capacity, enhancing enforcement, expanding social science expertise, and improving outreach programs. The study reveals mismatches between mandated activities and available resources, suggesting strategic reallocation or increased funding may benefit the agency in effectively addressing growing HMMI challenges.

Frontiers in Marine Science↗
USGS2001

Continental shelf GIS for the Monterey Bay National Marine Sanctuary

A marine sanctuary is an environment where the interests of science and society meet. Sanctuary managers need access to the best scientific data available that describe the environment and environmental processes in sanctuaries. Seafloor mapping and sampling in the Monterey Bay National Marine Sanctuary have revealed new details about the geology, morphology, and active geologic processes of this region. Data from sidescan sonar, multibeam sonar bathymetry, physical samples, and instrument moorings, are consolidated with new and existing maps in a geographic information system (GIS). The GIS provides researchers and policymakers a view of the relationship among data sets to assist science studies and to help with economic and social policy-making decisions regarding this protected environment.

California↗
USGS2010

NetCDF-CF-OPeNDAP: Standards for ocean data interoperability and object lessons for community data standards processes

It is generally recognized that meeting society's emerging environmental science and management needs will require the marine data community to provide simpler, more effective and more interoperable access to its data. There is broad agreement, as well, that data standards are the bedrock upon which interoperability will be built. The path that would bring the marine data community to agree upon and utilize such standards, however, is often elusive. In this paper we examine the trio of standards 1) netCDF files; 2) the Climate and Forecast (CF) metadata convention; and 3) the OPeNDAP data access protocol. These standards taken together have brought our community a high level of interoperability for "gridded" data such as model outputs, satellite products and climatological analyses, and they are gaining rapid acceptance for ocean observations. We will provide an overview of the scope of the contribution that has been made. We then step back from the information technology considerations to examine the community or "social" process by which the successes were achieved. We contrast the path by which the World Meteorological Organization (WMO) has advanced the Global Telecommunications System (GTS) - netCDF/CF/OPeNDAP exemplifying a "bottom up" standards process whereas GTS is "top down". Both of these standards are tales of success at achieving specific purposes, yet each is hampered by technical limitations. These limitations sometimes lead to controversy over whether alternative technological directions should be pursued. Finally we draw general conclusions regarding the factors that affect the success of a standards development effort - the likelihood that an IT standard will meet its design goals and will achieve community-wide acceptance. We believe that a higher level of thoughtful awareness by the scientists, program managers and technology experts of the vital role of standards and the merits of alternative standards processes can help us as a community to reach our interoperability goals faster.

Conference Paper↗
USGS2008

Monitoring lingering oil from the Exxon Valdez spill on Gulf of Alaska armored beaches and mussel beds sixteen years post-spill

Final Rept. ; Prepared in Cooperation With Alaska Univ., Fairbanks. Inst. of Arctic Biology. Sponsored By National Marine Fisheries Service, Juneau, Ak. Alaska Fisheries Science Center. ; Stranded Exxon Valdez Oil Has Persisted for 16 Years At Boulder- Armored Beach Sites Along National Park Coastlines Bordering the Gulf of Alaska . These Sites Are Up to 640 Km From the Spill Origin and Were Contaminated By Oil Mousse, a Viscous Water-in- Oil Emulsion. Although Surface Oil Has Continued to Decline, Subsurface Oiling Persists in Patches. Especially Striking Is the General Lack of Weathering of Stranded Oil on Armored Beaches Over the Last 16 Years . At Three of the Four Sites Where Oil Was Sampled in 2005, the Oil Was Compositionally Similar to 11-Day Old Exxon Valdez Oil , Even After 16 Years . The Formation of Mousse Allowed Less-Weathered Oil to Be Transported Long Distances. The Sequestration of the Oil Beneath a Boulder Armor, Coupled With the Stability of the Boulder Armoring (Investigated By Examining Movement of Marked Boulders), Had Contributed to the Lengthy Persistence of This Stranded Oil. Opportunistic Sampling of Several Previously Studied Oiled Mussel Beds Indicates Continued Contamination of At Least One of the Sites By Not Very Weathered Exxon Valdez Oil. Long-Term Persistence of Oil in These Habitats Should Cause Reconsideration of Response Activities After Spills, and May Influence the Environmental Sensitivity Indices Applied to These Habitats.

Report↗