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Future scenarios of land-use and land-cover change in the United States--the Marine West Coast Forests Ecoregion

Detecting, quantifying, and projecting historical and future changes in land use and land cover (LULC) has emerged as a core research area for the U.S. Geological Survey (USGS). Changes in LULC are important drivers of changes to biogeochemical cycles, the exchange of energy between the Earth’s surface and atmosphere, biodiversity, water quality, and climate change. To quantify the rates of recent historical LULC change, the USGS Land Cover Trends project recently completed a unique ecoregion-based assessment of late 20th century LULC change for the western United States. To characterize present LULC, the USGS and partners have created the National Land Cover Database (NLCD) for the years 1992, 2001, and 2006. Both Land Cover Trends and NLCD projects continue to evolve in an effort to better characterize historical and present LULC conditions and are the foundation of the data presented in this report. Projecting future changes in LULC requires an understanding of the rates and patterns of change, the major driving forces, and the socioeconomic and biophysical determinants and capacities of regions. The data presented in this report is the result of an effort by USGS scientists to downscale the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emission Scenarios (SRES) to ecoregions of the conterminous United States as part of the USGS Biological Carbon Sequestration Assessment. The USGS biological carbon assessment was mandated by Section 712 of the Energy Independence and Security Act of 2007. As part of the legislative mandate, the USGS is required to publish a methodology describing, in detail, the approach to be used for the assessment. The development of future LULC scenarios is described in chapter 3.2 and appendix A. Spatial modeling is described in chapter 3.3.2 and appendix B and in Sohl and others (2011). In this report, we briefly summarize the major components and methods used to downscale IPCC-SRES scenarios to ecoregions of the conterminous United States, followed by a description of the Marine West Coast Forests Ecoregion, and lastly a description of the data being published as part of this report.

California;Oregon;Washington↗

Spatial distribution of elevation change monitoring in coastal wetlands across protected lands of the lower 48 United States

Introduction Tidally influenced coastal wetlands, both saline and fresh, appear where terrestrial and marine environments meet and are considered important ecosystems for identifying the impacts of climate change. Coastal wetlands provide valuable benefits to society and the environment in the form of flood protection, water-quality improvements, and shoreline erosion reduction, making them one of the most important ecosystems in the world. Historically, these ecosystems have vertically adjusted to match rising sea levels through biologic and physical processes, but they are increasingly vulnerable to submergence as sea-level rise accelerates. Measuring vertical change on lands protected from human influence allows scientists to understand how vulnerable coastal wetlands are to submergence. But to fully understand this vulnerability, scientists must identify where vertical change in coastal wetlands is being measured across the lower 48 United States, a task that has not yet been undertaken. In this Fact Sheet, we document the spatial distribution of vertical change measurements in coastal wetlands to inform where gaps may still be in the Surface Elevation Table–Marker Horizon (SET-MH) coverage within protected lands across the lower 48 United States.

Fact Sheet↗

Tektite 1, man-in-the-sea project: Marine Science Program

The Tektite experiment was designed to provide data for a number of behavioral, biomedical, and engineering studies in addition to the marine sciences program. Conditions for some of these studies were not altogether compatible with the program for the marine sciences. For example, isolation imposed by human behavioral studies precluded physical contact with the surface team, even though such contact was physically possible and desirable for the conduct of the marine sciences program. Isolation also imposed on the scientific team the duty of all in-habitat maintenance, both scheduled and unscheduled, thereby taking substantial time from scientific research. In addition, between 10 and 20 percent of the waking time was devoted to performance of psychological tests required for the biomedical studies. Most of the experiments were directed toward detecting potentially adverse changes and thus were accepted as necessary and desirable. The only health problem to affect the scientific program during the dive was a minor external ear infection contracted by all the divers. Nonetheless, the experiment demon. strated, at least to our satisfaction, the advantages of underwater habitation and saturation diving for biological and geological research. A major advantage is the opportunity for continuous monitoring of organisms or processes. In addition, underwater habitation provides for considerably more research time in the water than surface diving or intermittent bottom dwelling, and this advantage increases greatly as the depth of habitation increases. Even in the relatively shallow depths at which Tektite 1 was conducted, the undersea team could spend appreciably more time at work in the water than their colleagues on the surface. Finally, Tektite 1 demonstrated that the scientist who lives in the sea need not have the extensive qualifications of a professional diver. Of the four scientists of the in-habitat team, only Crew Chief Waller was so qualified; the other three had used scuba as a research tool, but on a relatively limited basis. Any healthy, well-conditioned marine scientist with a basic diving background is capable of extending his research into the shallow sea on a full-time basis. It is hoped that many such scientists will in the future be able to utilize the undersea laboratory.

Science↗

Robotic environmental DNA bio-surveillance of freshwater health

Autonomous water sampling technologies may help to overcome the human resource challenges of monitoring biological threats to rivers over long time periods and large geographic areas. The Monterey Bay Aquarium Research Institute has pioneered a robotic Environmental Sample Processor (ESP) that overcomes some of the constraints associated with traditional sampling since it can automate water sample filtration and preservation of the captured material or homogenize it for immediate analyses in situ. The ESP was originally developed for marine environment applications. Here we evaluated whether the ESP can provide reliable, timely information on environmental (e)DNA detections of human and fish pathogens and introduced fishes at U.S. Geological Survey streamgage sites in freshwater rivers. We compared eDNA collected via ESP at high frequency (e.g., every 3 h) with manual eDNA collections collected at lower frequency (e.g., weekly). We found that water samples filtered and preserved by ESPs successfully detected the DNA of human pathogens, fish pathogens and introduced fishes. Both ESP and manually collected samples provided similar information about target DNA presence. We suggest that the greatest current benefit of the ESP is the cost savings of high frequency, bio-surveillance at remote or hard to access sites. The full potential of robotic technologies like the ESP will be realized when they can more easily execute in situ analyses of water samples and rapidly transmit results to decision-makers.

Idaho, Montana, Wyoming↗

Editorial: From cold seeps to hydrothermal vents: Geology, chemistry, microbiology, and ecology in marine and coastal environments

This Research Topic compiles contemporary studies on cold seeps, hydrothermal vents, mud volcanoes, and related seafloor features that are associated with focused fluid emissions and the transfer of carbon, other chemical species, and sometimes heat from the geosphere to the ocean. Because these features sometimes tap fluids and gas originating kilometers below the seafloor, they provide an important window into deep processes that are otherwise inaccessible to scientists. At the shallow portion of their journey, migrating fluids nearing the seafloor contribute to a range of unique biological, physical, and chemical processes within the sediments themselves and at the sediment-water interface. Seafloor fluid emissions play a critical role in global biogeochemical cycles, ocean chemistry, and possibly even climate change. Seafloor leakage points often emit hydrocarbon gases (especially methane and CO 2 ) and are sometimes the loci for deposition of seafloor minerals that have economic value. A burgeoning area of research focuses on natural products generated at these features, seeking compounds with potential pharmaceutical or other applications. Multidisciplinary studies have become routine for characterization of seafloor fluid emission sites, attesting to the inseparability of geologic, physical, chemical, and biological processes in these settings. It is increasingly common for researchers to combine in a single research cruise: subbottom imaging and seafloor mapping; porewater and water column geochemistry and gas sampling; sediment retrieval for lithologic, biostratigraphic, and solid phase analyses; and studies of benthic and subseafloor communities at the microbial to macrofaunal scales. This multidisciplinary approach has the advantage of ensuring the spatial and temporal coincidence of surveys and samples, an important factor at highly dynamic seafloor fluid emission sites. In addition, researchers often use remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), or human-occupied vehicles (HOVs) to record video of the seafloor, compile photomosaics, collect targeted samples, and survey with high-resolution geophysical near-seafloor systems, providing a degree of detail about seafloor fluid emission sites that is unprecedented compared to most areas of the deep ocean. While rarer, long-term cabled observatories or shorter-term deployments of portable observatories are also used at some loci for seafloor fluid flux and are particularly helpful for capturing temporal variations at these dynamic features. Here we summarize the Research Topic’s contribution to multidisciplinary seafloor emission studies in the categories of cold seeps, mud volcanoes, and hydrothermal vents. Figure 1 shows the geographic distribution of the studies in this Research Topic and key features referred to in this Introduction.

Frontiers in Earth Science↗

Deep-sea coral research and technology program: Alaska deep-sea coral and sponge initiative final report

Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska’s marine waters. In some places, such as the central and western Aleutian Islands, deep-sea coral and sponge resources can be extremely diverse and may rank among the most abundant deep-sea coral and sponge communities in the world. Many different species of fishes and invertebrates are associated with deep-sea coral and sponge communities in Alaska. Because of their biology, these benthic invertebrates are potentially impacted by climate change and ocean acidification. Deepsea coral and sponge ecosystems are also vulnerable to the effects of commercial fishing activities. Because of the size and scope of Alaska’s continental shelf and slope, the vast majority of the area has not been visually surveyed for deep-sea corals and sponges. NOAA’s Deep Sea Coral Research and Technology Program (DSCRTP) sponsored a field research program in the Alaska region between 2012–2015, referred to hereafter as the Alaska Initiative. The priorities for Alaska were derived from ongoing data needs and objectives identified by the DSCRTP, the North Pacific Fishery Management Council (NPFMC), and Essential Fish Habitat-Environmental Impact Statement (EFH-EIS) process. This report presents the results of 15 projects conducted using DSCRTP funds from 2012-2015. Three of the projects conducted as part of the Alaska deep-sea coral and sponge initiative included dedicated at-sea cruises and fieldwork spread across multiple years. These projects were the eastern Gulf of Alaska Primnoa pacifica study, the Aleutian Islands mapping study, and the Gulf of Alaska fish productivity study. In all, there were nine separate research cruises carried out with a total of 109 at-sea days conducting research. The remaining projects either used data and samples collected by the three major fieldwork projects or were piggy-backed onto existing research programs at the Alaska Fisheries Science Center (AFSC).

NOAA Technical Memorandum↗

Disturbance to desert soil ecosystems contributes to dust-mediated impacts at regional scales

This review considers the regional scale of impacts arising from disturbance to desert soil ecosystems. Deserts occupy over one-third of the Earth’s terrestrial surface, and biological soil covers are critical to stabilization of desert soils. Disturbance to these can contribute to massive destabilization and mobilization of dust. This results in dust storms that are transported across inter-continental distances where they have profound negative impacts. Dust deposition at high altitudes causes radiative forcing of snowpack that leads directly to altered hydrological regimes and changes to freshwater biogeochemistry. In marine environments dust deposition impacts phytoplankton diazotrophy, and causes coral reef senescence. Increasingly dust is also recognized as a threat to human health.

Biodiversity and Conservation↗

Contaminant removal by wastewater treatment plants in the Stillaguamish River Basin, Washington

Human activities in most areas of the developed world typically release nutrients, pharmaceuticals, personal care products, pesticides, and other contaminants into the environment, many of which reach freshwater ecosystems. In urbanized areas, wastewater treatment plants (WWTPs) are critical facilities for collecting and reducing the amounts of wastewater contaminants (WWCs) that ultimately discharge to rivers, coastal areas, and groundwater. Most WWTPs use multiple methods to remove contaminants from wastewater. These include physical methods to remove solid materials (primary treatment), biological and chemical methods to remove most organic matter (secondary treatment), advanced methods to reduce the concentrations of various contaminants such as nitrogen, phosphorus and (or) synthetic organic compounds (tertiary treatment), and disinfection prior to discharge (Metcalf and Eddy, Inc., 1979). This study examined the extent to which 114 organic WWCs were removed by each of three WWTPs, prior to discharge to freshwater and marine ecosystems, in a rapidly developing area in northwestern Washington State. Removal percentages for each WWC were estimated by comparing the concentrations measured in the WWTP influents with those measured in the effluents. The investigation was carried out in the 700-mi 2 Stillaguamish River Basin, the fifth largest watershed that discharges to Puget Sound (fig. 1).

Washington↗

Lessons from the past: isotopes of an endangered rail as indicators of underlying change to tidal marsh habitats

Introduction: Tidal marsh systems along the Pacific coast of the United States have experienced substantial stress and loss of area and ecosystem function, which we examined by using the endangered California Ridgway’s Rail, Rallus obsoletus obsoletus (‘rail’) as an indicator of its tidal marsh habitat in the San Francisco Estuary. We organized a collection of historical (1885-1940) and modern (2005-2014) rail feathers and analyzed the feather isotope means for delta carbon (δ 13 C), sulfur (δ 34 S), and nitrogen (δ 15 N) by region and time period. Outcomes: Feather isotopes represented the primary foraging habitat during historical then modern time periods. Neither individual nor regional rail feather isotopes suggested freshwater or terrestrial foraging by the rail. Three regions with both historic and modern feather isotopes revealed non-uniform spatial shifts in isotope levels consistent with a marine based food web and significant δ 15 N enrichment. Discussion: Our results supported the rail’s status as a generalist forager and obligate tidal marsh species throughout the historic record. The variable isoscape trends generated from feather isotope means illustrated a modern loss of the isotopic homogeneity between regions of historical tidal marsh, which correlated with spatially-explicit habitat alterations such as increasing biological invasions and sewage effluent over time. Conclusion: These findings have reinforced the importance of tidal marsh conservation in the face of ongoing underlying changes to these important ecosystems.

California↗

Water quality in southern Florida: Florida, 1996-98

Major influences and findings for water quality and biology in southern Florida, including the Everglades, are described and illustrated. Samples were collected to determine total phosphorus, dissolved organic carbon, pesticides, mercury, nitrate, volatile organic carbon compounds, and radon-222. Water-management, agricultural, and land-use practices are discussed. Sixty-three species of fish in 26 families were collected; 43 native species, 10 exotic or nonnative species, and 10 species of marine fish that periodically inhabit canals and rivers were identified.

Florida↗

Seabird tissue archival and monitoring project: Egg collections and analytical results 1999-2002

In 1998, the U.S. Geological Survey Biological Resources Division (USGS-BRD), the U.S. Fish and Wildlife Service (USFWS) Alaska Maritime National Wildlife Refuge (AMNWR), and the National Institute of Standards and Technology (NIST) began the Seabird Tissue Archival and Monitoring Project (STAMP) to collect and cryogenically bank tissues from seabirds in Alaska for future retrospective analysis of anthropogenic contaminants. The approach of STAMP was similar to that of the Alaska Marine Mammal Tissue Archival Project (AMMTAP). AMMTAP was started in 1987 by NIST and the National Oceanic and Atmospheric Administration (NOAA) as part of the Outer Continental Shelf Environmental Assessment Program sponsored by the Minerals Management Service. Presently sponsored by the USGS-BRD, AMMTAP continues its work as part of a larger national program, the Marine Mammal Health and Stranding Response Program. AMMTAP developed carefully designed sampling and specimen banking protocols. Since 1987, AMMTAP has collected tissues from marine mammals taken in Alaska Native subsistence hunts and has cryogenically banked these tissues at the NIST National Biomonitoring Specimen Bank (NBSB). Through its own analytical work and working in partnership with other researchers both within and outside Alaska, AMMTAP has helped to develop a substantial database on contaminants in Alaska marine mammals. In contrast, data and information is limited on contaminants in Alaska seabirds, which are similar to marine mammals in that they feed near the top of the food chain and have the potential for accumulating anthropogenic contaminants. During its early planning stages, STAMP managers identified the seabird egg as the first tissue of choice for study by the project. There is a relatively long history of using bird eggs for environmental monitoring and for investigating the health status of bird populations. Since 1998, protocols for collecting and processing eggs, and cryogenically banking egg samples have been developed by STAMP (see York et al. 2001). Eggs are being collected on an annual basis for several species at nesting colonies throughout Alaska. Aliquots of these egg samples are being analyzed on a regular basis for persistent organic pollutants and mercury. Results of this work have been published in scientific journals (Christopher et al. 2002) and in conference proceedings (Kucklick et al. 2002; Vander Pol et al. 2002a, 2002b). The intent of this report is to provide an up-to-date description of STAMP. The report contains the most recent egg collection inventory, analytical data, preliminary interpretations based on these data, and a discussion of possible future directions of the project.

Report↗

Exxon Valdez Oil Spill Restoration Project final report: Monitoring for evaluation of recovery and restoration of injured nearshore resources

In 2012, we completed three consecutive years of full field sampling in WPWS for EVOS Restoration Project 10100750. Nearshore monitoring was conducted in collaboration with the NPS SWAN I&M program and, beginning in 2012, as part of the EVOSTC GWA program. Data collection was done in accordance with standard operating procedures set forth to monitor marine water chemistry and quality, marine intertidal invertebrates, kelps and seagrasses, marine birds, black oystercatchers, and sea otters. Summer sampling in 2012 represented the fourth year of sampling in WPWS (an initial year of sampling was done in WPWS in 2007; EVOS Restoration Project 070750). Based on our monitoring of nearshore species in WPWS, and comparisons of data from WPWS and other areas within the Gulf of Alaska, we have no evidence of continued injury to biological resources at the spatial scales we are monitoring. A key finding is that recovery of the sea otter population is no longer constrained by exposure to lingering oil; this is consistent with related EVOSTC studies on harlequin ducks (Restoration Project 12120114-Q). We anticipate continued annual nearshore monitoring in WPWS and at KATM and KEFJ under GWA, with data summaries and analyses including all three areas to provide a larger spatial and temporal context to the understanding of processes and patterns in nearshore ecosystems of the GOA which were impacted by the EVOS of 1989.

Alaska↗

Climate vulnerability assessment for Pacific salmon and steelhead in the California Current Large Marine Ecosystem

Major ecological realignments are already occurring in response to climate change. To be successful, conservation strategies now need to account for geographical patterns in traits sensitive to climate change, as well as climate threats to species-level diversity. As part of an effort to provide such information, we conducted a climate vulnerability assessment that included all Pacific salmon and steelhead (Oncorhynchus spp.) listed under the U.S. Endangered Species Act. Using an expert-based scoring system, we ranked 20 attributes for the 28 listed units, and 5 additional units. Attributes captured biological sensitivity, or the strength of linkages between each listing unit and the present climate; climate exposure, or the magnitude of projected change in local environmental conditions; and adaptive capacity, or the ability to modify phenotypes to cope with new climatic conditions. Each listing unit was then assigned one of four vulnerability categories.

California↗

Flying under the radar: The demographic importance of immatures in long-lived seabird populations

Demographic assessments are essential for effective biological conservation management, allowing early detection of population declines and timely allocation of resources to avoid possible crises. For species with slow life-history strategies like seabirds, only the breeding adults are monitored routinely. The dynamics of immatures, often unobservable from fledging to recruitment, are less well understood and typically not accounted for in conservation status assessments. Here, we quantify the importance of changes in the survival and abundance of immatures in shaping the past and forecasted dynamics of a long-lived marine top-predator. We use integrated population models (IPM) incorporating the dynamics of immatures, based on multi-decadal demographic monitoring of the black-browed albatross ( Thalassarche melanophris ) at three globally important breeding sites. The populations showed differences in breeding and survival rates, highlighting a degree of life history flexibility in response to the environment. Using a retrospective sensitivity analysis, we consistently identified immature survival as the key contributor to population growth rate. At all sites, even those with increasing or stable breeding populations, the total population has been declining, largely due to decreases in immature survival. Although not directly apparent from counts, this decline is already underway and is projected to emerge at the level of the breeding population over the coming three generations. This contrasts with a model focusing solely on counts of breeding adults, which mostly indicate an overall population increase. Collectively, our findings highlight that conservation assessments must account for the dynamics of subadult stages, or risk providing an inaccurate picture of population status.

Biological Conservation↗

Year-to-year fluctuation of the spring phytoplankton bloom in south San Francisco Bay: An example of ecological variability at the land-sea interface

Estuaries are transitional ecosystems at the interface of the terrestrial and marine realms. Their unique physiographic position gives rise to large spatial variability, and to dynamic temporal variability resulting, in part, from a variety of forces and fluxes at the oceanic and terrestrial boundaries. River flow, in particular, is an important mechanism for delivering watershed-derived materials such as fresh water, sediments, and nutrients; each of these quantities in turn directly influences the physical structure and biological communities of estuaries. With this setting in mind, we consider here the general proposition that estuarine variability at the yearly time scale can be caused by annual fluctuations in river flow. We use a “long-term” (15-year) time series of phytoplankton biomass variability in South San Francisco Bay (SSFB), a lagoon-type estuary in which phytoplankton primary production is the largest source of organic carbon ( Jassby et al. 1993 ).

California↗

Marine ecotourism for small pelagics as a source of alternative income generating activities to fisheries in a tropical community

Overharvest has led to marine ecosystem degradation and declining fishery catches in many tropical communities. To allow stocks to recover and provide increased flows of food and income, reductions in fishing effort are necessary. The development of Alternative Income Generating Activities can help to reduce the economic reliance of coastal communities on fishing, potentially reducing pressure on fish stocks. Here we assess the local conditions which have enabled the creation of Alternative Income Generating Activities to fishing based on marine ecotourism in Moalboal, Philippines. Importantly, while marine ecotourism typically centers around charismatic megafauna, a combination of nearshore fringing reefs, the establishment of nearshore marine protected areas and the occurrence of a massive herring aggregation provide a large tourism draw to this community. Using a combination of regional and local economic statistics and stakeholder surveys, we implement an economic valuation of the Moalboal marine ecotourism for 2018 and compare this valuation to an independent estimate of the extractive value of the herring aggregation. The Moalboal case indicates that a combination of strong community engagement in the governance of the ecotourism resource, a network of locally managed marine protected areas and the retention and distribution of economic benefits within the local community have led to a significant marine ecotourism sector. We contextualize these conditions into a set of potential enabling conditions for marine ecotourism as an Alternative Income Generating Activity to fishing to contribute insights to diversifying livelihood opportunities beyond extractive fishing for coastal communities in the tropics.

Moalboal, Cebu Island↗

Increased sediment load during a large-scale dam removal changes nearshore subtidal communities

The coastal marine ecosystem near the Elwha River was altered by a massive sediment influx—over 10 million tonnes—during the staged three-year removal of two hydropower dams. We used time series of bathymetry, substrate grain size, remotely sensed turbidity, scuba dive surveys, and towed video observations collected before and during dam removal to assess responses of the nearshore subtidal community (3 m to 17 m depth). Biological changes were primarily driven by sediment deposition and elevated suspended sediment concentrations. Macroalgae, predominantly kelp and foliose red algae, were abundant before dam removal with combined cover levels greater than 50%. Where persistent sediment deposits formed, macroalgae decreased greatly or were eliminated. In areas lacking deposition, macroalgae cover decreased inversely to suspended sediment concentration, suggesting impacts from light reduction or scour. Densities of most invertebrate and fish taxa decreased in areas with persistent sediment deposition; however, bivalve densities increased where mud deposited over sand, and flatfish and Pacific sand lance densities increased where sand deposited over gravel. In areas without sediment deposition, most invertebrate and fish taxa were unaffected by increased suspended sediment or the loss of algae cover associated with it; however, densities of tubeworms and flatfish, and primary cover of sessile invertebrates increased suggesting benefits of increased particulate matter or relaxed competition with macroalgae for space. As dam removal neared completion, we saw evidence of macroalgal recovery that likely owed to water column clearing, indicating that long-term recovery from dam removal effects may be starting. Our results are relevant to future dam removal projects in coastal areas and more generally to understanding effects of increased sedimentation on nearshore subtidal benthic communities.

Washington↗

Southeastern freshwater fishes

North America has the richest fauna of temperate freshwater fishes in the world, with about 800 native species in the waters of Canada and the United States. The center of this diversity is in the southeastern United States, where as many as 500 species may exist (62% of the continental fauna north of Mexico). Many coastal marine species also enter fresh waters of the Southeast, and at least 34 foreign fish species are established in the region. Although freshwater fishes of the United States are better studied than any fish fauna of comparable scope in the world (Lee et al. 1980; Hocutt and Wiley 1986; Matthews and Heins 1987; Page and Burr 1991; Mayden 1992), large gaps exist in scientific knowledge about the biology and ecology of most species. New species are still being discovered, and the taxonomy of other species is being refined. Seriously declining populations of freshwater fishes in the United States concern the scientific community (Deacon et al. 1979; Williams et al. 1989; Moyle and Leidy 1992; Warren and Burr 1994). This article briefly summarizes the current conservation status of southeastern freshwater fishes; the Southeast is emphasized because of its important fish biodiversity and to focus attention on the growing problem of adverse human impacts on the region's aquatic habitats (Mount 1986; Burkhead and Jenkins 1991; Etnier and Starnes 1991; Warren and Burr 1994).

Book chapter↗