Washington Coast Research Articles

Hg concentrations in fish from coastal waters of California and Western North America

The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3μg/gwet weight (ww), and 10 locations an average above 1.0μg/gww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds.

Insights into the Underwater Behavior, Species Interactions, and Biomechanics of Baleen Whales using Suction‐Cup Attached Video and Inertial Sensors

Bio‐logging approaches to study the biology of free‐ranging animals often focus on audio, movement, or video, but rarely are these different data streams integrated. Here we custom engineered a tag to measure the fine‐scale kinematics of cetaceans while simultaneously recording animal‐borne video from dual cameras. The movement sensors included a pressure transducer, tri‐axial inertial sensors (accelerometers, magnetometers, gyroscopes), and a paddle‐wheel speed sensor. We deployed these tags on blue whales, fin whales, and humpback whales off the coast of California during the summer months of 2014 and 2015, and 2 gray whales off the coast of Washington in April 2015. For the first time, we observed a wide‐range of behaviors of the tagged whale, conspecifics, and parasites. These included interactions between whale lice, aggregations of prey (krill, anchovies) and non‐prey species that the whales encountered, remora swimming and attachment behavior, echelon swimming formations with other whales, and feeding with other whales and sea lions. During some deployments we were able to observe how the movements of flippers and flukes are involved in facilitating different maneuvers including lunge feeding. For example, when the tags were pointed perpendicularly to the long axis of the whale's body, we could detect simultaneous movement of flipper and fluke, highlighting the fine‐scale body control and varied use of different propulsion and control surfaces. By combining video and kinematic data, this tag design serves as an important tool for understanding the biomechanics and behavioral ecology of large aquatic vertebrates.

Increasing virulence, but not infectivity, associated with serially emergent virus strains of a fish rhabdovirus.

Surveillance and genetic typing of field isolates of a fish rhabdovirus, infectious hematopoietic necrosis virus (IHNV), has identified four dominant viral genotypes that were involved in serial viral emergence and displacement events in steelhead trout (Oncorhynchus mykiss) in western North America. To investigate drivers of these landscape-scale events, IHNV isolates designated 007, 111, 110, and 139, representing the four relevant genotypes, were compared for virulence and infectivity in controlled laboratory challenge studies in five relevant steelhead trout populations. Viral virulence was assessed as mortality using lethal dose estimates (LD50), survival kinetics, and proportional hazards analysis. A pattern of increasing virulence for isolates 007, 111, and 110 was consistent in all five host populations tested, and correlated with serial emergence and displacements in the virus-endemic lower Columbia River source region during 1980–2013. The fourth isolate, 139, did not have higher virulence than the previous isolate 110. However, the mG139M genotype displayed a conditional displacement phenotype in that it displaced type mG110M in coastal Washington, but not in the lower Columbia River region, indicating that factors other than evolution of higher viral virulence were involved in some displacement events. Viral infectivity, measured as infectious dose (ID50), did not correlate consistently with virulence or with viral emergence, and showed a narrow range of variation relative to the variation observed in virulence. Comparison among the five steelhead trout populations confirmed variation in resistance to IHNV, but correlations with previous history of virus exposure or with sites of viral emergence varied between IHNV source and sink regions. Overall, this study indicated increasing viral virulence over time as a potential driver for emergence and displacement events in the endemic Lower Columbia River source region where these IHNV genotypes originated, but not in adjacent sink regions.

Money Trees: The Douglas Fir and American Forestry, 1900–1944 by Emily K. Brock

Reviews MONEY TREES: THE DOUGLAS FIR AND AMERICAN FORESTRY, 1900–1944 by Emily K. Brock Oregon State University Press, Corvallis, 2015. Illustrations, maps, notes, bibliography, index. 256 pages. $27.95 paper. In her new book Money Trees, environmental historian Emily Brock traces the evolution of forestry as a scientific field of study and the outsized role that Douglas fir forests in the Pacific Northwest played in shaping the profession. Federal land managers and private timberland owners alike wanted to maximize profit on the Doug fir lands but avoid the damage caused by aggressive harvests that years earlier wrecked lands and economies across the Northeast, the Great Lakes, and the South. According to Brock, local imperatives from the Oregon and Washington coasts shaped national debates about the utility of forestry as a science and its role in forest management. American forestry at the turn of the century was primarily a prescriptive science, meaning it focused on how to efficiently grow trees. Ecology, on the other hand, was a descriptive science that studied the components of a forest and how they interacted. The heart of the book is Brock’s examination of the differences between these two fields as well as early foresters ’ efforts to direct the profession toward one approach or the other. The first Chief of the Forest Service, Gifford Pinchot — himself the first American trained as a forester — placed the agency at the cutting edge of this debate. He created a science and research branch within the Forest Service and placed Raphael Zon at its head. Together they advocated and set the agency on a course to examine and study how trees interacted with local environments using the descriptive pattern of inquiry from ecology. Money and politics, particularly in the Doug fir lands, soon changed the course of forestry and the management of the National Forests. In the 1930s, the Great Depression tightened its grip on the American economy. The enormous amount of potential capital in harvestable timber in Oregon and Washington promised relief and changed the political calculus of the timber industry, the federal government, and the debate within forestry about the purpose of the new profession. New Deal programs directed the Forest Service to employ Americans in forestry-related work and focus on sustainable harvests in the Pacific Northwest. Some professional foresters saw an opportunity to put their knowledge of silviculture to good use while Zon and Pinchot favored, in their minds, a purer scientific focus of analyzing the ecosystem and how it worked. This debate played out in the policy corridors of the Forest Service in Washington, D.C., as well as on the pages of profession’s leading journal, the Journal of Forestry. Zon and ecological foresters lost the war over the direction of forestry. The profession took a decided turn on federal and private lands in the 1940s toward maximizing harvests. Beginning in the Pacific Northwest, sustainable yield shaped the profession for decades to come. So thoroughly did the profession and the Forest Service adopt sustainable yield and maximizing harvests on the profession and the Forest Service that a number of influential foresters, including Aldo Leopold and Robert Marshall, left the agency and formed the Wilderness Society in part to advocate for a different focus within the forestry profession. The battles fought in the 1930s and 1940s over the direction of the forestry profession were re-fought in the 1970s when ecological forestry reappeared. By the 1990s, ecological forestry was the de facto policy — a transition that is chronicled in Samuel Hays’s book War in the Woods. Such was the impact of this shift within the profession and the management of federal lands as a whole. Brock’s book is a good primer to understanding that science is never static and is rarely the sole determiner in land management policy: culture, politics, economics, and capital all play parts in determining the course of federal forest policy. This book would be very appropriate for graduate classes in the history of science and environmental history, particularly for those interested in the history of public land management and in Oregon history. Lincoln Bramwell Washington, D.C. 103 ...

Book Review: Culture, Politics, and Climate Change: How Information Shapes Our Common Future, edited by Deserai A. Crow and Maxwell T. Boykoff

Culture, Politics, and Climate Change: How Information Shapes Our Common Future. Deserai A. Crow and Maxwell T. Boykoff, eds. London, UK: Routledge, 2015. 225 pp. $155 hbk. $49.95 pbk.Given that global warming (a.k.a. climate change) may be the greatest existential threat challenging the future of the human race and the flora and fauna with which we share the Earth, we have seen no shortage of books describing the problem, and proposing various solutions. Co-editor Maxwell T. Boykoff, who has been a major figure in honing a focus in human communication vis-a-vis climate change, does not contribute directly to this collection (except as a co-editor), but his work is often cited because it provides important frame for discussion, most notably Balance as Bias: Global Warming and the U.S. Prestige Press (2004) in Global Environmental Change.This is a collection of papers, and as with many such collections, quality is uneven.However, this book raises some provocative questions. In its first chapter, for example, Cheryl Hall asks whether gloom and doom warnings may be counterproductive, an ineffective frame . . . fostering resistance, apathy, and or despair instead of hope and motivation to change. This is important issue that affects how people respond to what, for most, is a slow-motion crisis often parsed in the future tense, even as temperatures rise, droughts and deluges intensify, the Arctic ice cap melts, and the oceans acidify to the point where some mussels along the Washington Coast have gone sterile.The gloom-and-doom scenario intensifies as scientists and risk communicators shout louder, to try and shake some sense into people. For example, scientists may explain the nature of thermal inertia: takes roughly 50 years for greenhouse emissions into the atmosphere to affect the geophysical system; thus, the climate we experience today is a reaction to the greenhouse-gas levels of the 1960s. Scientists who understand the geophysics thus share a sense of urgency often not shared by others. Hall asserts that divorcing positive visions from necessary sacrifices is a false choice, and that It will have to be both. Thus, we can share some good news about wind and solar power, which are becoming cost competitive with fossil fuels for electricity generation. In 2014, for the first time, new installed electric capacity in wind and solar exceeded that of oil, gas, and coal.Matthew Tegelberg, Dmitry Yagodin, and Adrienne Russell point out in #CLIMATENEWS: Summit Journalism and Digital Networks that news coverage of global warming reached a peak in 2007, with considerable attention to Al Gore's Inconvenient Truth, as well as a Nobel Prize for the Intergovernmental Panel on Climate Change (IPCC). …

Chum Salmon Genetic Diversity in the Northeastern Pacific Ocean Assessed with Single Nucleotide Polymorphisms (SNPs): Applications to Fishery Management

AbstractWe examined genetic diversity patterns among 55 collections of Chum Salmon from the northeastern Pacific Ocean using 89 single nucleotide polymorphisms (SNPs). The distribution of Chum Salmon samples extended from the Nass River along the coast of British Columbia and along the coast of Washington as far south as the Columbia River. Chum Salmon represented three previously defined run‐groups: fall (primarily), summer, and winter. Genetic variation at SNP loci, as measured by FST, ranged from 0.002 to 0.279 over all collections and averaged 0.062 over all loci. Similar to the genetic patterns detected with microsatellites and allozymes, genetic variation followed a regional structure along geographic distance, with genetic diversity being highest in the north and decreasing southward, then increasing in and near the Columbia River. Within Puget Sound, Washington, genetic variation was structured further according to run timing (fall, summer, and winter) and shared ancestry. Simulations indicated that this suite of SNPs is powerful for identifying regional components in a Chum Salmon mixed fishery. Because of the transferability of SNP data, the growing SNP baseline for Chum Salmon will be useful for multiple agencies managing Chum Salmon around the Pacific Rim.Received December 19, 2014; accepted May 20, 2015

Ichthyoplankton distribution and abundance in relation to nearshore dissolved oxygen levels and other environmental variables within the Northern California Current System

Nearshore hypoxia along the coast of Oregon and Washington is a seasonal phenomenon that has generated concern among scientists studying this temperate upwelling ecosystem. These waters are affected by coastal upwelling-induced hypoxia mainly during late summer and fall, but the effects of low oxygen levels on fish and invertebrate communities, particularly during the early-life history stages, are poorly known. We investigated the effects of hypoxia and other variables on the species composition, density, vertical and horizontal distribution of fish larvae along the Oregon and Washington coasts during the summers of 2008, 2009 and 2010. Bottom-dissolved oxygen (DO) values ranged from 0.49 to 4.79 mL L−1, but the overall water column DO values were only moderately hypoxic during the 3 yr of sampling compared with recent extreme years. In this study, DO was found to be an environmental parameter affecting the species composition, but other variables such as season, year and depth of capture were also important. Although the overall density of fish larvae increased with increasing bottom-DO values, the effect on individual species density was limited. Slender sole (Lyopsetta exilis) and sand sole (Psettichthys melanostictus) were the only species to have a weak trend of density with DO, but both showed negative relationships and neither relationship was significant. Our results indicate that larval fish spatial distribution was only moderately affected within the range of observed oxygen values, but low DO may be an important factor under intense hypoxic conditions.

Satellite chlorophyll off the British Columbia Coast, 1997-2010

We examine the spatial and temporal variability of satellite-sensed sea surface chlorophyll off the west coast of North America from 1997 to 2010, with focus on coastal British Columbia. The variability in surface chlorophyll is complex. Whereas the spring bloom generates the highest phytoplankton concentration for coastal Alaska, the north and east coasts of Haida Gwaii, Queen Charlotte Sound, the Strait of Georgia, and coastal Oregon and California, it is the fall bloom that normally generates the highest concentration for the west coast of Vancouver Island, Juan de Fuca Strait, and the west coast of Washington. The highest satellite-sensed chlorophyll concentrations occur in the Strait of Georgia, where mean values are at least 2 times higher than elsewhere in the northeast Pacific. Moreover, the annual average surface chlorophyll concentration increased significantly in the Strait of Georgia during this period, with highest concentration observed during the near neutral ENSO conditions of the spring of 2007. The next highest concentrations occur off southwest Vancouver Island but have no statistically significant trend. The lowest average peak chlorophyll concentration is observed off Southern California. The timing of the highest chlorophyll concentration is latest off the coast of Washington and earliest off the coast of Southern California. Small increasing concentration trends are observed off the Washington and California coasts.

The Contributions to Storm Tides in Pacific Northwest Estuaries: Tillamook Bay, Oregon, and the December 2007 Storm

ABSTRACT Cheng, T.K.; Hill, D.F., and Read, W., 2015. The contributions to storm tides in Pacific Northwest estuaries: Tillamook Bay, Oregon, and the December 2007 storm. The December 2007 storm, otherwise known as the Great Coastal Gale of 2007, was a series of extratropical cyclones that brought highly unprecedented wind speeds and precipitation to the Oregon and Washington coasts of the United States. A storm hindcast using the coupled Advanced Circulation (ADCIRC) and Simulating Waves Nearshore (SWAN) models was conducted within Tillamook Bay, Oregon, from 28 November to 5 December 2007. ADCIRC computes two-dimensional circulation forced by astronomic tides, streamflow, and storm surge, while SWAN solves the wave action density equations for radiation stresses. Modeled nontidal residuals were compared to observed data collected by the National Oceanic and Atmospheric Administration at the Garibaldi, Oregon, tide gauge station. The relative contributions of meteorological forcing, offshore waves, and s...

A MATLAB GEODETIC SOFTWARE FOR PROCESSING AIRBORNE LIDAR BATHYMETRY DATA

Abstract. The ability to build three-dimensional models through technologies based on satellite navigation systems GNSS and the continuous development of new sensors, as Airborne Laser Scanning Hydrography (ALH), data acquisition methods and 3D multi-resolution representations, have contributed significantly to the digital 3D documentation, mapping, preservation and representation of landscapes and heritage as well as to the growth of research in this fields. However, GNSS systems led to the use of the ellipsoidal height; to transform this height in orthometric is necessary to know a geoid undulation model. The latest and most accurate global geoid undulation model, available worldwide, is EGM2008 which has been publicly released by the U.S. National Geospatial-Intelligence Agency (NGA) EGM Development Team. Therefore, given the availability and accuracy of this geoid model, we can use it in geomatics applications that require the conversion of heights. Using this model, to correct the elevation of a point does not coincide with any node must interpolate elevation information of adjacent nodes. The purpose of this paper is produce a Matlab® geodetic software for processing airborne LIDAR bathymetry data. In particular we want to focus on the point clouds in ASPRS LAS format and convert the ellipsoidal height in orthometric. The algorithm, valid on the whole globe and operative for all UTM zones, allows the conversion of ellipsoidal heights using the EGM2008 model. Of this model we analyse the slopes which occur, in some critical areas, between the nodes of the undulations grid; we will focus our attention on the marine areas verifying the impact that the slopes have in the calculation of the orthometric height and, consequently, in the accuracy of the in the 3-D point clouds. This experiment will be carried out by analysing a LAS APRS file containing topographic and bathymetric data collected with LIDAR systems along the coasts of Oregon and Washington (USA).

Seasonal and interannual oxygen variability on the Washington and Oregon continental shelves

AbstractThe coastal waters of the northern portion of the California Current System experience a seasonal decline in oxygen concentrations and hypoxia over the summer upwelling season that results in negative impacts on habitat for many organisms. Using a regional model extending from 43°N to 50°N, with an oxygen component developed in this study, drivers of seasonal and regional oxygen variability are identified. The model includes two pools of detritus, which was an essential addition in order to achieve good agreement with the observations. The model was validated using an extensive array of hydrographic and moored observations. The model captures the observed seasonal decline as well as spatial trends in bottom oxygen. Spatially, three regions of high respiration are identified as locations where hypoxia develops each modeled year. Two of the regions are previously identified recirculation regions. The third region is off of the Washington coast. Sediment oxygen demand causes the region on the Washington coast to be susceptible to hypoxia and is correlated to the broad area of shallow shelf (<60 m) in the region. Respiration and circulation‐driven divergence contribute similar (60, 40%, respectively) amounts to the integrated oxygen budget on the Washington coast while respiration dominates the Oregon coast. Divergence, or circulation, contributes to the oxygen dynamics on the shelf in two ways: first, through the generation of retention features, and second, by determining variability.

Evaluating the ecological and behavioural factors influencing Snowy PloverCharadrius nivosusegg hatching and the potential benefits of predator exclosures

SummaryAn understanding of the ecological factors influencing nest success and the effectiveness of management activities focused on improving nest success can be critical to successful conservation strategies for rare or declining species. Over seven breeding seasons (2006–2012) we examined the influence of nest spacing and habitat characteristics on hatching success for the nationally threatened Pacific coast population of the Snowy PloverCharadrius nivosusin coastal Washington, USA in two study areas. Specifically, we assessed the influence of clutch age, nesting season date, distance to conspecific nests, perpendicular distance to the high-tide (wrack) line, vegetation cover and other habitat characteristics at three spatial scales (1m2, 5m2, and 25 m2) centred on the nest. We also assessed the effectiveness of wire mesh cages placed around nests to exclude mammalian and avian nest-predators. We discovered and monitored 307 nests, placed predator exclosures around 142 of these nests and measured habitat variables at 251. Our selected base model included site and quadratic function of season-date. For the analysis examining habitat effects on nest success, only models with distance to nearest active nest ranked higher than the baseline model even when removing the nests that were very distant from conspecific nests (outliers). For these unexclosed nests, predation was the primary source of nest failure and crows and ravens were apparently the primary nest predators. Predator exclosures had a clear positive influence on nest survival. Even though we observed a positive exclosure effect, we recommend that they be used cautiously because we and others have observed adult mortality associated with exclosures. Regardless of the spatial scale, Snowy Plovers are primarily using nest sites with little vegetation, shell or woody material cover suggesting the need for large expanses of very sparsely or unvegetated habitats that allow birds to nest semi-colonially (with near neighbours).

Dedicated beach surveys along the central Washington coast reveal a high proportion of unreported marine mammal strandings

JESSICA L. HUGGINS, Cascadia Research Collective, 218 1⁄2 W. Fourth Avenue, Olympia, Washington 98501, U.S.A.; JOSH OLIVER and DYANNA M. LAMBOURN, Washington Department of Fish and Wildlife, Marine Mammal Investigations, 7801 Phillips Road, Lakewood, Washington 98498, U.S.A; JOHN CALAMBOKIDIS, Cascadia Research Collective, 218 1⁄2 W. Fourth Avenue, Olympia, Washington 98501, U.S.A.; BETHANY DIEHL and STEVEN JEFFRIES, Washington Department of Fish and Wildlife, Marine Mammal Investigations, 7801 Phillips Road, Lakewood, Washington 98498, U.S.A.

Estimating Storm-Induced Dune Erosion and Overtopping along U.S. West Coast Beaches

Mull, J. and Ruggiero, P., 2014. Estimating storm-induced dune erosion and overtopping along U.S. West Coast beaches.Coastal foredunes protect lives, infrastructure, and ecosystems during severe storms. A range of approaches, ranging from simple (e.g., geometric) to complex (e.g., process based) predictive models, have been developed to quantify overtopping and foredune retreat during storms. At present, however, there is no widely accepted approach for assessing the vulnerability of coastal foredunes to erosion and overtopping hazards. Because different coastal regions have distinct storm and geomorphic characteristics, models need to be assessed and possibly adapted before they can be successfully applied to each unique region. In this study we apply a total water level (TWL) model and three simple foredune erosion models and assess their suitability for U.S. West Coast vulnerability analyses. The erosion models include a geometric model, an equilibrium profile model, and a wave impact model. We discuss the assumptions required to implement each model and force them with hydrodynamic conditions associated with a large-scale laboratory dune erosion experiment and a major winter storm approximately equivalent to the 30 year return period (TWL) event in the U.S. Pacific Northwest. The models are each applied with beach and foredune characteristics extracted from airborne topographic LiDAR (light detection and ranging) data collected along the coasts of Oregon and Washington. Sensitivity tests reveal distinct differences in model dependence on beach slope, a critical parameter in determining storm water level elevations and ultimately the extent of foredune retreat. Without detailed, reliable field observations of storm-induced dune erosion from the region, the accuracy of each model is determined using results of the dune erosion experiment. Estimates of both overtopping and erosion extent are normalized by foredune dimensions, enabling comparisons of relative vulnerability between different reaches of coast.

Predator exclosures, predator removal, and habitat improvement increase nest success of Snowy Plovers in Oregon, USA

Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, USA, to Baja California, Mexico, and in disjunct interior sites. The Pacific coast population is federally listed as Threatened; habitat loss and nest loss to a suite of terrestrial and avian predators are thought to be primary factors limiting population growth in this species. In coastal Oregon, USA, a consortium of state and federal management agencies deployed nest exclosures on active Snowy Plover nests, initiated a lethal predator management program, and conducted local-scale habitat management in an effort to boost local productivity. During 1990–2009, we monitored 1,951 Snowy Plover nests at 9 sites with varying treatments. We examined the effectiveness of 3 types of nest exclosures (large, small, and outfitted with electric wire), predator removal, and habitat management on nest survival. Habitat management to remove invasive grasses and provide more suitable nesting substrate more than doubled nest survival. Predator management or use of any of the 3 types of exclosures also affected nest survival. There appeared to be no additional benefit to using both approaches, but the biological relevance of these findings is unclear because of site differences in treatments applied. Importantly, these management techniques only affected nesting success; their effect on other contributions to population viability (e.g., fledging success) was not correlated with nesting success. This long-term study illustrates the short-term benefits and tradeoffs of using nest exclosures, predator management, and habitat restoration to improve nesting success. Although we gained broader insight into the relative efficacy of common management techniques to improve avian nesting success, we cannot yet determine how improved nest success contributes to population growth.

Estimating shallow water sound power levels and mitigation radii for theR/VMarcusG.Langsethusing an 8 km long MCS streamer

For seismic surveys in shallow-water environments, the complexity of local geology and seafloor topography can make it difficult to accurately predict associated sound levels and establish appropriate mitigation radii required to ensure the safety of local marine protected species. This is primarily because necessary detailed information regarding the local seafloor topography and subseafloor geology is often unavailable before a survey begins. One potential solution to this problem is to measure received levels using the ship's multichannel seismic (MCS) streamer, which could allow for the dynamic real-time determination of sound levels and mitigation radii while a survey is underway. We analyze R/V Langseth streamer data collected on the shelf and slope near the Washington coast during the Cascadia Open-Access Seismic Transects (COAST) and Ridge2Trench projects to measure received levels up to a distance of approximately 8 km from the sound source array. We establish methods to filter, clean, and process streamer data to accurately determine received power levels and confidently establish mitigation radii. We show that in shallow water measured power levels can fluctuate due to the influence of seafloor topographic features, but that the use of the streamer for the establishment of dynamic mitigation radii is feasible and should be further pursued. The establishment of mitigation radii based on local conditions may help to maximize the safety of marine protected species while also maximizing the ability of researchers to conduct seismic studies.

Growth and condition of juvenile coho salmon Oncorhynchus kisutch relate positively to species richness of trophically transmitted parasites.

The aims of this study were first, to test the hypothesis that metrics of fish growth and condition relate positively to parasite species richness (S(R)) in a salmonid host; second, to identify whether S(R) differs as a function of host origin; third, to identify whether acquisition of parasites through marine v. freshwater trophic interactions was related to growth and condition of juvenile salmonids. To evaluate these questions, species diversity of trophically transmitted parasites in juvenile coho salmon Oncorhynchus kisutch collected off the coast of the Oregon and Washington states, U.S.A. in June 2002 and 2004 were analysed. Fish infected with three or more parasite species scored highest in metrics of growth and condition. Fish originating from the Columbia River basin had lower S(R) than those from the Oregon coast, Washington coast and Puget Sound, WA. Parasites obtained through freshwater or marine trophic interactions were equally important in the relationship between S(R) and ocean growth and condition of juvenile O. kisutch salmon.

Rethinking turbidite paleoseismology along the Cascadia subduction zone

A stratigraphic synthesis of dozens of deep-sea cores, most of them overlooked in recent decades, provides new insights into deepsea turbidites as guides to earthquake and tsunami hazards along the Cascadia subduction zone, which extends 1100 km along the Pacific coast of North America. The synthesis shows greater variability in Holocene stratigraphy and facies off the Washington coast than was recognized a quarter century ago in a confluence test for seismic triggering of sediment gravity flows. That test compared counts of Holocene turbidites upstream and downstream of a deep-sea channel junction. Similarity in the turbidite counts among seven core sites provided evidence that turbidity currents from different submarine canyons usually reached the junction around the same time, as expected of widespread seismic triggering. The fuller synthesis, however, shows distinct differences between tributaries, and these differences suggest sediment routing for which the confluence test was not designed. The synthesis also bears on recent estimates of Cascadia earthquake magnitudes and recurrence intervals. The magnitude estimates hinge on stratigraphic correlations that discount variability in turbidite facies. The recurrence estimates require turbidites to represent megathrust earthquakes more dependably than they do along a flow path where turbidite frequency appears limited less by seismic shaking than by sediment supply. These concerns underscore the complexity of extracting earthquake history from deep-sea turbidites at Cascadia.

Fortuitous encounters between seagliders and adult female northern fur seals (Callorhinus ursinus) off the Washington (USA) coast: upper ocean variability and links to top predator behavior.

Behavioral responses by top marine predators to oceanographic features such as eddies, river plumes, storms, and coastal topography suggest that biophysical interactions in these zones affect predators' prey, foraging behaviors, and potentially fitness. However, examining these pathways is challenged by the obstacles inherent in obtaining simultaneous observations of surface and subsurface environmental fields and predator behavior. In this study, migratory movements and, in some cases, diving behavior of 40 adult female northern fur seals (NFS; Callorhinus ursinus) were quantified across their range and compared to remotely-sensed environmental data in the Gulf of Alaska and California Current ecosystems, with a particular focus off the coast of Washington State (USA) – a known foraging ground for adult female NFS and where autonomous glider sampling allowed opportunistic comparison of seal behavior to subsurface biophysical measurements. The results show that in these ecosystems, adult female habitat utilization was concentrated near prominent coastal topographic, riverine, or inlet features and within 200 km of the continental shelf break. Seal dive depths, in most ecosystems, were moderated by surface light level (solar or lunar), mirroring known behaviors of diel vertically-migrating prey. However, seal dives differed in the California Current ecosystem due to a shift to more daytime diving concentrated at or below the surface mixed layer base. Seal movement models indicate behavioral responses to season, ecosystem, and surface wind speeds; individuals also responded to mesoscale eddies, jets, and the Columbia River plume. Foraging within small scale surface features is consistent with utilization of the inner coastal transition zone and habitats near coastal capes, which are known eddy and filament generation sites. These results contribute to our knowledge of NFS migratory patterns by demonstrating surface and subsurface behavioral responses to a spatially and temporally dynamic ocean environment, thus reflecting its influence on associated NFS prey species.

Geologic history of Siletzia, a large igneous province in the Oregon and Washington Coast Range: Correlation to the geomagnetic polarity time scale and implications for a long-lived Yellowstone hotspot

Siletzia is a basaltic Paleocene and Eocene large igneous province in coastal Oregon, Washington, and southern Vancouver Island that was accreted to North America in the early Eocene. New U-Pb magmatic, detrital zircon, and 40Ar/39Ar ages constrained by detailed field mapping, global nannoplankton zones, and magnetic polarities allow correlation of the volcanics with the 2012 geologic time scale. The data show that Siletzia was rapidly erupted 56–49 Ma, during the Chron 25–22 plate reorganization in the northeast Pacific basin. Accretion was completed between 51 and 49 Ma in Oregon, based on CP11 (CP—Coccolith Paleogene zone) coccoliths in strata overlying onlapping continental sediments. Magmatism continued in the northern Oregon Coast Range until ca. 46 Ma with the emplacement of a regional sill complex during or shortly after accretion. Isotopic signatures similar to early Columbia River basalts, the great crustal thickness of Siletzia in Oregon, rapid eruption, and timing of accretion are consistent with offshore formation as an oceanic plateau. Approximately 8 m.y. after accretion, margin parallel extension of the forearc, emplacement of regional dike swarms, and renewed magmatism of the Tillamook episode peaked at 41.6 Ma (CP zone 14a; Chron 19r). We examine the origin of Siletzia and consider the possible role of a long-lived Yellowstone hotspot using the reconstruction in GPlates, an open source plate model. In most hotspot reference frames, the Yellowstone hotspot (YHS) is on or near an inferred northeast-striking Kula-Farallon and/or Resurrection-Farallon ridge between 60 and 50 Ma. In this configuration, the YHS could have provided a 56–49 Ma source on the Farallon plate for Siletzia, which accreted to North America by 50 Ma. A sister plateau, the Eocene basalt basement of the Yakutat terrane, now in Alaska, formed contemporaneously on the adjacent Kula (or Resurrection) plate and accreted to coastal British Columbia at about the same time. Following accretion of Siletzia, the leading edge of North America overrode the YHS ca. 42 Ma. The voluminous high-Ti basaltic to alkalic magmatism of the 42–35 Ma Tillamook episode and extension in the forearc may be related to the encounter with an active YHS. Clockwise rotation of western Oregon about a pole in the backarc has since moved the Tillamook center and underlying Siletzia northward ∼250 km from the probable hotspot track on North America. In the reference frames we examined, the YHS arrives in the backarc ∼5 m.y. too early to match the 17 Ma magmatic flare-up commonly attributed to the YHS. We suggest that interaction with the subducting slab may have delayed arrival of the plume beneath the backarc.