Search

Efforts are underway to restore the Salish Sea, a 16,925 km2 inland sea shared by Washington State, USA, and British Columbia, Canada. A list of the birds and mammals that use this marine ecosystem is lacking. We compiled information from varied sources and identified 172 bird and 37 mammal species that depend on the Salish Sea marine ecosystem. Of these species, 72 bird and 29 mammal species are both highly dependent on intertidal or marine habitat as well as on marine derived food. One hundred bird species and 8 mammal species that use the Salish Sea marine ecosystem have varying degrees of dependence on the marine and terrestrial ecosystems to meet significant life history needs. These interactions between the marine and terrestrial ecosystems indicate the need to integrate marine and terrestrial restoration efforts to achieve long-term conservation of the suite of birds and mammals that use and depend on the marine ecosystem. This comprehensive list of avian and mammal fauna for the Salish Sea serves as a foundation for determining the occurrence of new species and the disappearance of others, enables selection of species as indicators for ecosystem health, and also provides a basis for identifying the mechanisms responsible for marine bird and mammal declines. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the changes in the abundance of non-breeding-season marine birds in the Salish Sea, Strait of Georgia, British Columbia from 1975 to 2007. The Puget Sound Ambient Monitoring Program (PSAMP), surveys by Western Washington University (WWU) of marine bird abundance, and Christmas Bird Counts (CBCs) found reductions in the abundance of several overwintering marine bird species between 1978-1979 and the 1990s and 2003-2005. Researchers emphasized that the stabilization, as well as the recovery of marine bird populations wintering in the Salish Sea will need restoration of degraded local landscapes and protection and restoration of breeding locations.

The article presents a study which examines the impact of coastal net fisheries utilizing marine bird strandings on bycatch and beached birds in the Salish Sea in British Columbia and Washington. According to researchers, majority of the fisheries-associated marine bird strandings were opportunistic appearances initially noted by members of the public. In order to determine the relative significance of fisheries mortality, researchers computed the cumulative magnitude of beached bird carcasses from every mortality sources. They found that more than 10,000 sea bird carcasses would have been seen annually on the shores of the Salish Sea.

This paper introduces official responsibility for the protection and management of the Salish Sea marine environment. Focusing on governments and their legally constituted bodies, the complex management structures on the American and Canadian sides of the Salish Sea are identified. Both countries operate in cooperative federalist systems, but there exist differences in management structures arising notably from constitutional differences, Tribal and First Nation relations, and jurisdictional authority. Both state and provincial governments have the authority to create and enforce environmental regulations but are constrained by federal legislation. Collaborative and stakeholder-engaged environmental planning and stewardship have been recognized on both sides of the border. Past and present efforts support bottom-up organizational structures that give community members and scientists a greater voice in decision-making, in partnership with government. More evidence exists of community- and state-level autonomy in Washington compared to British Columbia. Political and administrative boundaries have been recognized by some as counter to needs of environmental management, with an alternative and preferred approach being the use of ecological planning units such as watersheds or estuaries. The international boundary dividing the Salish Sea remains an administrative and organizational impediment despite evidence of trans-boundary collaborative efforts. [Display omitted] • Official responsibilities and management structures differ between the USA and Canada because of respective constitutions, Tribal and First Nation relations, and jurisdictional authority.. • Washington State and British Columbia enforce environmental regulations but are constrained by federal legislation.. • Collaborative and stakeholder-engaged environmental planning and stewardship have been recognized on both sides of the border. • The international boundary remains an administrative and organizational impediment despite evidence of trans-boundary collaborative efforts. [ABSTRACT FROM AUTHOR]

Cryptococcus gattii is a fungal pathogen that primarily affects the respiratory and nervous systems of humans and other animals. C. gattii emerged in temperate North America in 1999 as a multispecies outbreak of cryptococcosis in British Columbia (Canada) and Washington State and Oregon (USA), affecting humans, domestic animals, and wildlife. Here we describe the C. gattii epizootic in odontocetes. Cases of C. gattii were identified in 42 odontocetes in Washington and British Columbia between 1997 and 2016. Species affected included harbor porpoises Phocoena phocoena (n = 26), Dall's porpoises Phocoenoides dalli (n = 14), and Pacific white-sided dolphins Lagenorhynchus obliquidens (n = 2). The probable index case was identified in an adult male Dall's porpoise in 1997, 2 yr prior to the initial terrestrial outbreak. The spatiotemporal extent of the C. gattii epizootic was defined, and cases in odontocetes were found to be clustered around terrestrial C. gattii hotspots. Case-control analyses with stranded, uninfected odontocetes revealed that risk factors for infection were species (Dall's porpoises), age class (adult animals), and season (winter). This study suggests that mycoses are an emerging source of mortality for odontocetes, and that outbreaks may be associated with anthropogenic environmental disturbance.

Preliminary evidence suggests that Chinook salmon Oncorhynchus tshawytscha from the Yukon River may be more susceptible to Ichthyophonus sp. infections than Chinook from stocks further south. To investigate this hypothesis in a controlled environment, we experimentally challenged juvenile Chinook from the Yukon River and from the Salish Sea with Ichthyophonus sp. and evaluated mortality, infection prevalence and infection load over time. We found that juvenile Chinook salmon from a Yukon River stock were more susceptible to ichthyophoniasis than were those from a Salish Sea stock. After feeding with tissues from infected Pacific herring Clupea pallasii, Chinook salmon from both stocks became infected. The infection was persistent and progressive in Yukon River stock fish, where infections sometimes progressed to mortality, and histological examinations revealed parasite dissemination and proliferation throughout the host tissues. In Salish Sea-origin fish, however, infections were largely transient; host mortalities were rare, and parasite stages were largely cleared from most tissues after 3-4 wk. Susceptibility differences were evidenced by greater cumulative mortality, infection prevalence, parasite density, proportion of fish demonstrating a cellular response, and intensity of the cellular response among fish from the Yukon River stock. These observed differences between Chinook salmon stocks were consistent when parasite exposures occurred in both freshwater and seawater. These results support the hypothesis that a longer-standing host-pathogen relationship, resulting in decreased disease susceptibility, exists among Salish Sea Chinook salmon than among Yukon River conspecifics.

This paper presents a modeling assessment of storm surge in the Salish Sea—a large and complex estuarine system in the Pacific Northwest that is exposed to extratropical cyclones. A method was developed to systematically identify storm surge events in the Salish Sea based on water level records at four representative tidal gauges in the Salish Sea. The maximum storm surge distribution in the Salish Sea was calculated based on model simulations of 34 major historical storm events from 1980 to 2016. The model simulations were validated by field observations of water level and velocity using a suite of model performance metrics. Model results suggest that the maximum storm surge in the Salish Sea is generally in the range of 0.8 m–1.03 m and is heterogeneous in space. The model results also show a strong north-south gradient with larger surge magnitudes occurring in the north that is primarily caused by the southerly wind in winter months. The sensitivity analysis of wind forcing suggested that storm surge in the Salish Sea is dominated by the remote surge from the Pacific Ocean, and the local wind contributes up to approximately 20% of the surge variability. This paper systematically elucidates storm surge characteristics and potential risk in the Salish Sea. • Distribution of maximum storm surge height in the Salish Sea was mapped based on 34 storm surge simulations. • Storm surge in the Salish Sea is dominated by remote surge off the coast, and local wind plays a secondary role. • Storm surge height can be amplified in the sub-basins of Puget Sound because of interaction with complex geometry. [ABSTRACT FROM AUTHOR]

The prevalence of Ichthyophonus infection in Pacific herring Clupea pallasii was spatially heterogeneous in the southern Salish Sea, Washington State, USA. Over the course of 13 mo, 2232 Pacific herring were sampled from 38 midwater trawls throughout the region. Fork length was positively correlated with Ichthyophonus infection at all sites. After controlling for the positive relationship between host size and Ichthyophonus infection, the probability of infection was approximately 6-fold higher in North Hood Canal than in Puget Sound and the northern Straits (12 vs. 2% predicted probability for a 100 mm fish and 30 vs. 7% predicted probability for a 180 mm fish). Temporal changes in Ichthyophonus infection probability were explained by seasonal differences in fish length, owing to Pacific herring life history and movement patterns. Reasons for the spatial heterogeneity remain uncertain but may be associated with density-dependent factors inherent to the boom-bust cycles that commonly occur in clupeid populations.

The Harbor Porpoise normally occurs in groups of 2 to 5 individuals. We report a sighting of 74 Harbor Porpoises near the entrance to Vancouver Harbor, Canada. When corrected for detection underestimate, this group was possibly as numerous as 1894 individuals, which we call a super pod [ABSTRACT FROM AUTHOR]

Estuaries are important mediators in the transport of freshwater, sediment, and dissolved material into the ocean, and many studies have investigated mean estuarine circulation. However, it is not clear how descriptions of the mean circulation are linked to the motion of individual water parcels, or of discrete items floating within the system, nor how they related to the variability in this dispersal. An obvious approach to characterizing this variability is to actually measure dispersal by tracking Lagrangian drifters. Recent technological advances have dramatically decreased the cost of satellite-tracked and monitored drifters, making longer deployments of large numbers of expendable drifters much more feasible. Here we take advantage of this opportunity to directly characterize the seaward flow and dispersion of surface water in a relatively well-studied estuarine system (the Salish Sea on the NE Pacific coast), combining 2200 drifter-days of data from more than 400 tracked drifters with the deployment of nearly 6000 traditional driftcards. Residence times in different parts of the system estimated from the drifter observations are similar but systematically lower than those derived from other methods, and we speculate that this may be because surface drifts are faster than layer-mean drifts in a fjord-type estuarine system. We also find that drifters tend to ground on shore, and that time to-grounding from different source locations has an approximately exponential distribution with a mean of only a few days, much less than the transport time to the ocean. The estuary is therefore a highly efficient trap for floating objects. Finally, we quantify a dispersion coefficient, finding that dispersion is a critical component of transport in parts of the Salish Sea, often much more important than mean advection. The mean is visible only after averaging for weeks or months. [ABSTRACT FROM AUTHOR]

• Phytoplankton in the Strait of Georgia is highly variable over space and time. • No single environmental driver can effectively explain variations in phytoplankton. • Phytoplankton in the Northern Strait of Georgia is linked to climate indices. • Phytoplankton in the Central Strait of Georgia is influenced by localized factors. The Strait of Georgia is a dynamic region with substantial spatio-temporal variability at lower trophic levels. This variability, in turn, may directly impact resident and migratory fish populations that are of major economic importance. MODIS-Aqua satellite products were used to provide a comprehensive spatial analysis of phytoplankton dynamics from 2003 to 2016 in the Northern and Central Strait of Georgia (SoG) in order to examine the relationships between environmental drivers and satellite-derived chlorophyll a (Chl a). Positive SST anomalies predominated between 2003–2006 and 2013–2016, with the strongest anomalies occurring from 2014 to 2016. Strong positive anomalies in Fraser River discharge, coupled with fewer wind events, led to early stratification during spring 2005 and 2015, resulting in moderate to strong anomalies in Chl a concentrations. Chl a in the Northern SoG was most highly correlated with SST and PAR (r s = 0.41, p < 0.01 and r s = 0.38, p < 0.01, respectively), whereas Chl a in the Central SoG was most highly correlated with Fraser River discharge (r s = 0.43, p < 0.01). Annual median Chl a anomalies were tightly coupled with large-scale climate indices (PDO, NPGO, SOI) in the Northern region; however, no such relationships were observed in the Central SoG, suggesting that variability in Chl a in the Central region is more strongly influenced by localized factors. Results from this study provide critical information regarding the key environmental drivers influencing spatio-temporal dynamics of Chl a in the SoG. [ABSTRACT FROM AUTHOR]

Numerous restoration projects are underway in Puget Sound, Washington, USA with the goal of re-establishing intertidal wetlands that were historically lost due to dike construction for flood protection and agricultural development. One such effort is the restoration effort within the Stillaguamish Delta, benefitting from the cumulative effects from the Leque Island and zis a ba restoration projects. The preferred restoration design calls for the removal of perimeter dikes at the two sites and the creation of tidal channels to facilitate the drainage of tidal flows. A 3-D high-resolution unstructured-grid coastal ocean model based on FVCOM was developed to evaluate the hydrodynamic response of the estuary to restoration alternatives. A series of hydrodynamic modeling simulations were then performed to quantify the hydrodynamic response of the nearshore restoration project, such as periodic inundation, suitable currents, and desired habitat/salinity levels. Sediment impacts were also examined, including the potential for excessive erosion or sedimentation requiring maintenance. Simulation results indicate that the preferred alternative scenario provides the desired estuarine response, which is consistent with the planned design. A decrease in velocities and bed shear in the main river channels was noted for the restored condition associated with the increased inundation of tidal flat area and reduced tidal flows through the main channels. High bed shear near the restored tidal channel entrances indicates that the inlets may evolve in size until equilibrium is established. [ABSTRACT FROM AUTHOR]

Floating structures such as barges and ships affect near-field hydrodynamics and create a zone of influence (ZOI). Extent of the ZOI is of particular interest due to potential obstruction to and impact on out-migrating juvenile fish. Here, we present an assessment of ZOI from Hood Canal (Floating) Bridge, located within the 110-km-long fjord-like Hood Canal sub-basin in the Salish Sea, Washington. A field data collection program allowed near-field validation of a three-dimensional hydrodynamic model of Hood Canal with the floating bridge section embedded. The results confirm that Hood Canal Bridge, with a draft of 4.6 m covering ~85% of the width of Hood Canal, obstructs the brackish outflow surface layer. This induces increased local mixing near the bridge, causes pooling of water (up-current) during ebb and flood, and results in shadow/sheltering of water (down-current). The change in ambient currents, salinity, and temperature is highest at the bridge location and reduces to background levels with distance from the bridge. The ZOI extends ~20 m below the surface and varies from 2–3 km for currents, from 2–4 km for salinity, and from 2–5 km for temperature before the deviations with the bridge drop to <10% relative to simulated background conditions without the bridge present. [ABSTRACT FROM AUTHOR]

A major limitation for remote sensing analyses of oceanographic variables is loss of spatial data. The Data INterpolating Empirical Orthogonal Functions (DINEOF) method has demonstrated effectiveness for filling spatial gaps in remote sensing datasets, making them more easily implemented in further applications. However, the spatial and temporal coverage of the input image dataset can heavily impact the outcomes of using this method and, thus, further metrics derived from these datasets, such as phytoplankton bloom phenology. In this study, we used a three-year time series of MODIS-Aqua chlorophyll-a to evaluate the DINEOF reconstruction output accuracy corresponding to variation in the form of the input data used (i.e., daily or week composite scenes) and time series length (annual or three consecutive years) for a dynamic region, the Salish Sea, Canada. The accuracy of the output data was assessed considering the original chla pixels. Daily input time series produced higher accuracy reconstructing chla (95.08–97.08% explained variance, RMSExval 1.49–1.65 mg m−3) than did all week composite counterparts (68.99–76.88% explained variance, RMSExval 1.87–2.07 mg m−3), with longer time series producing better relationships to original chla pixel concentrations. Daily images were assessed relative to extracted in situ chla measurements, with original satellite chla achieving a better relationship to in situ matchups than DINEOF gap-filled chla, and with annual DINEOF-processed data performing better than the multiyear. These results contribute to the ongoing body of work encouraging production of ocean color datasets with consistent processing for global purposes such as climate change studies. [ABSTRACT FROM AUTHOR]

The Department of Energy's (DOE's) National Energy Technology Laboratory's (NETL's) Blowout and Spill Occurrence Model (BLOSOM), and the National Oceanic and Atmospheric Administration's (NOAA's) General NOAA Operational Modeling Environment (GNOME) are compared. Increasingly complex simulations are used to assess similarities and differences between the two models' components. The simulations presented here are forced by ocean currents from a Finite Volume Community Ocean Model (FVCOM) implementation that has excellent skill in representing tidal motion, and with observed wind data that compensates for a coarse vertical ocean model resolution. The comprehensive comparison between GNOME and BLOSOM presented here, should aid modelers in interpreting their results. Beyond many similarities, aspects where both models are distinct are highlighted. Some suggestions for improvement are included, e.g., the inclusion of temporal interpolation of the forcing fields (BLOSOM) or the inclusion of a deflection angle option when parameterizing wind-driven processes (GNOME). Overall, GNOME and BLOSOM perform similarly, and are found to be complementary oil spill models. This paper also sheds light on what drove the historical Point Wells spill, and serves the additional purpose of being a learning resource for those interested in oil spill modeling. The increasingly complex approach used for the comparison is also used, in parallel, to illustrate the approach an oil spill modeler would typically follow when trying to hindcast or forecast an oil spill, including detailed technical information on basic aspects, like choosing a computational time step. We discuss our successful hindcast of the 2003 Point Wells oil spill that, to our knowledge, had remained unexplained. The oil spill models' solutions are compared to the historical Point Wells' oil trajectory, in time and space, as determined from overflight information. Our hindcast broadly replicates the correct locations at the correct times, using accurate tide and wind forcing. While the choice of wind coefficient we use is unconventional, a simplified analytic model supported by observations, suggests that it is justified under this study's circumstances. We highlight some of the key oceanographic findings as they may relate to other oil spills, and to the regional oceanography of the Salish Sea, including recommendations for future studies. [ABSTRACT FROM AUTHOR]

Global expansion of oxygen-deficient (hypoxic) waters will have detrimental effects on marine life in the Northeast Pacific Ocean (NEP) where some of the largest proportional losses in aerobic habitat are predicted to occur. However, few in situ studies have accounted for the high environmental variability in this region while including natural community-assembly dynamics. Here, we present results from a 14-month deployment of a benthic camera platform tethered to the VENUS cabled observatory in the seasonally hypoxic Saanich Inlet. Our time series continuously recorded natural cycles of deoxygenation and reoxygenation that allowed us to test whether a community from the NEP showed hysteresis in its recovery compared to hypoxia-induced decline, and to address the processes driving temporal beta diversity under variable states of hypoxia. Using high-frequency ecological time series, we reveal (i) differences in the response and recovery of the epibenthic community are rate-limited by recovery of the sessile species assemblage; (ii) both environmental and biological processes influence community assembly patterns at multiple timescales; and (iii) interspecific processes can drive temporal beta diversity in seasonal hypoxia. Ultimately, our results illustrate how different timescale-dependent drivers can influence the response and recovery of a marine habitat under increasing stress from environmental change., Competing Interests: We have no competing interests

We summarize results of two independent studies on plastic pollution in the marine environment that overlap in time and space. One study evaluated the abundance of anthropogenic debris on 37 sandy beaches bordering the Salish Sea in Washington State while the other characterized plastic debris in surface waters of the Salish Sea and the Inside Passage to Skagway, Alaska. Both studies concluded that foam, primarily expanded polystyrene was the dominant pollutant. Plastic was found in surface waters the full length of the Inside Passage but was concentrated near harbors. At the wrack line, an average square meter of Washington's 1180km of sandy beaches in the Salish Sea had 61 pieces of anthropogenic debris weighing approximately 5g. The total loading for the entire 1m wide band is estimated to be 72,000,000 pieces and 5.8metric tons. Most anthropogenic debris on beaches is generated within the region., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The world's oceans have undergone significant ecological changes following European colonial expansion and associated industrialization. Seabirds are useful indicators of marine food web structure and can be used to track multidecadal environmental change, potentially reflecting long-term human impacts. We used stable isotope (δ(13)C, δ(15)N) analysis of feathers from glaucous-winged gulls (Larus glaucescens) in a heavily disturbed region of the northeast Pacific to ask whether diets of this generalist forager changed in response to shifts in food availability over 150 years, and whether any detected change might explain long-term trends in gull abundance. Sampled feathers came from birds collected between 1860 and 2009 at nesting colonies in the Salish Sea, a transboundary marine system adjacent to Washington, USA and British Columbia, Canada. To determine whether temporal trends in stable isotope ratios might simply reflect changes to baseline environmental values, we also analysed muscle tissue from forage fishes collected in the same region over a multidecadal timeframe. Values of δ(13)C and δ(15)N declined since 1860 in both subadult and adult gulls (δ(13)C, ~ 2-6‰; δ(15)N, ~4-5‰), indicating that their diet has become less marine over time, and that birds now feed at a lower trophic level than previously. Conversely, forage fish δ(13)C and δ(15)N values showed no trends, supporting our conclusion that gull feather values were indicative of declines in marine food availability rather than of baseline environmental change. Gradual declines in feather isotope values are consistent with trends predicted had gulls consumed less fish over time, but were equivocal with respect to whether gulls had switched to a more garbage-based diet, or one comprising marine invertebrates. Nevertheless, our results suggest a long-term decrease in diet quality linked to declining fish abundance or other anthropogenic influences, and may help to explain regional population declines in this species and other piscivores., (© 2014 John Wiley & Sons Ltd.)

Seabirds have been identified and used as indicators of ecosystem processes such as climate change and human activity in nearshore ecosystems around the globe. Temporal and spatial trends have been documented at large spatial scales, but few studies have examined more localized patterns of spatiotemporal variation, by species or functional group. In this paper, we apply spatial occupancy models to assess the spatial patchiness and interannual trends of 18 seabird species in the Puget Sound region (Washington State, USA). Our dataset, the Puget Sound Seabird Survey of the Seattle Audubon Society, is unique in that it represents a seven-year study, collected with a focus on winter months (October-April). Despite historic declines of seabirds in the region over the last 50 years, results from our study are optimistic, suggesting increases in probabilities of occurrence for 14 of the 18 species included. We found support for declines in occurrence for white-winged scoters, brants, and 2 species of grebes. The decline of Western grebes in particular is troubling, but in agreement with other recent studies that have shown support for a range shift south in recent years, to the southern end of California Current.