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Research about Washington

Source-linked reports with geographic coverage including Washington.

At least 127 records · Page 7Linked to original sources
USGS2024

Merging integrated population models and individual-based models to project population dynamics of recolonizing species

Recolonizing species exhibit unique population dynamics, namely dispersal to and colonization of new areas, that have important implications for management. A resulting challenge is how to simultaneously model demographic and movement processes so that recolonizing species can be accurately projected over time and space. We introduce a framework for spatially explicit projection modeling that harnesses the rigorous parameter estimation made possible by an integrated population model (IPM) and the flexible movement modeling made possible by an individual-based model (IBM). Our framework has two components: [1] a Bayesian IPM-driven age- and state-structured population model that governs the population state process and estimation of demographic rates, and [2] an IBM-driven spatial model that allows for the projection of dispersal and habitat colonization. We applied this model framework to estimate current and project future dynamics of gray wolves ( Canis lupus ) in Washington State, USA. We used data from 74 telemetered wolves and yearly pup and pack counts to parameterize the model, and then projected statewide dynamics over 50 years. Mean population growth was 1.29 (95 % Bayesian Credible Interval = 1.26–1.33) during initial recolonization from 2009 to 2020 and decreased to 1.02 (95 % Prediction Interval = 0.98–1.04) in the projection period (2021–2070). Our results suggest that gray wolves have an ~100 % probability of colonizing the last of Washington State's three specified recovery regions by 2030, regardless of alternative assumptions about how dispersing wolves select new territories. Our spatially explicit projection model can be used to project the dynamics of any species for which spatial spread is an important driver of population dynamics.

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USGS2024

A new method for bioassessment of ecosystems with complex communities and environmental gradients

Bioassessment of complex and heterogeneous ecosystems is a challenge when there are multiple, strong, natural environmental gradients; unknown, or spatially varying, mixtures of stressors; and large numbers of taxa with unknown responses to both the environmental gradients and the stressors. Current methods of bioassessment are not designed for use under this set of constraints. To address this gap, we have developed an assessment method appropriate for well-sampled, heterogeneous systems with many taxa. In the bioassessment described below, we model taxa occurrence as a function of natural environmental gradients, then use residual covariance patterns between all pairs of taxa to estimate the impact of human disturbance across sites as a latent construct. The derivation of the method from an underlying causal model allows the metric value at each site and the associated taxa responses to be partitioned into contributions from a set of putative stressors. We apply this method as a case study to the subtidal benthic invertebrate community of Puget Sound, WA (USA) and demonstrate a partial decomposition of the metric values to a set of stressors including sediment organic carbon, nitrogen, metals, and organic pollutants. While this method provides new opportunities to estimate, communicate, and understand the ecological condition of complex, heterogeneous ecosystems, due to the requirement for broad, detailed data to inform its estimates, it will likely be most appropriate for monitoring programs.

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USGS2024

Birdwatching preferences reveal synergies and tradeoffs among recreation, carbon, and fisheries ecosystem services in Pacific Northwest estuaries, USA

Coastal ecosystems provide multiple ecosystem services that are valued in diverse ways. The Nisqually River Delta (the Delta), an estuary in Puget Sound, Washington, U.S.A., is co-managed by the Nisqually Indian Tribe and the Billy Frank Jr. Nisqually National Wildlife Refuge. In an ecosystem services assessment, we used different service-appropriate methods including citizen science, statistical and geospatial models, and scenario analysis to evaluate three ecosystem services – recreational birdwatching, soil carbon accumulation and fishery production – indicated as priorities for the Refuge, Nisqually Indian Tribe, and surrounding communities. We developed a generalized additive mixed model set based on eBird mobile application birdwatching observations to understand the biological and landscape features that influence birdwatching and to project birdwatching visitation based on scenarios of Delta habitat change. We evaluated ecosystem service synergies and tradeoffs associated with habitat change for three coastal habitat types using scenario outputs from the birdwatching model and published results on Delta soil carbon accumulation and fishery production. The highest-ranked birdwatching models explained 88 % of the deviance and showed that visitation was greatest in winter months when distance to major cities was approximately 20 km. Recreational birdwatching increased with increasing area of forested wetland, emergent wetland, aquatic vegetation bed, open access, and total estuary. With increasing forested and emergent wetland area, recreational birdwatching, out-migrating juvenile Chinook salmon weight and soil carbon accumulation all increased. With increasing aquatic vegetation bed (resulting from sea level rise), recreational birdwatching increased, but salmon weight and soil carbon accumulation decreased. We identified practical ways in which ecosystem services may be incorporated into adaptive management frameworks that support climate adaptation decision making. This study illustrated how use of ecosystem services can help managers make decisions that have greater benefit for wildlife and people, communicate the societal value of decisions and increase local support and participation.

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USGS2024

Unscrambling the Proterozoic supercontinent record of northeastern Washington State, USA

The time interval from Supercontinent Nuna assembly in the late Paleoproterozoic to Supercontinent Rodinia breakup in the Neoproterozoic is considered by some geologists to comprise the “Boring Billion,” an interval possibly marked by a slowdown in plate tectonic processes. In northeastern Washington State, USA, similar to much of western Laurentia, early workers generally thought the tectonostratigraphic framework of this interval of geologic time consisted of two major sequences, the (ca. 1480–1380 Ma) Mesoproterozoic Belt Supergroup and unconformably overlying (<720 Ma) Neoproterozoic Windermere Supergroup. However, recent research indicates that strata considered by early workers as Belt Supergroup equivalents are actually younger, and a post-Belt, pre-Windermere record is present within the <1360 Ma Deer Trail Group and <760 Ma Buffalo Hump Formation. Thus, the northeastern Washington region perhaps comprises the most complete stratigraphic record of the “Boring Billion” time interval in the northwestern United States and holds important insights into global Proterozoic supercontinent tectonic processes. In light of these exciting developments, this field guide will address the early historic economic geology and original mapping of these Proterozoic sequences in the northeastern Washington region, and from that foundation explore more recent isotopic provenance data and their regional to global context. Finally, the guide will end with a discussion of remaining questions with a goal of stimulating interest in these relatively understudied, yet important, rocks.

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USGS2024

Incorporating life history diversity in an integrated population model to inform viability analysis

Life history diversity can significantly affect population dynamics and effects of management actions. For instance, variation in individual responses to environmental variability can reduce extirpation risk to populations, as the portfolio effect dampens temporal variability in abundance. Moreover, differences in habitat use may cause individuals to respond differently to habitat management and climate variability. To explore the role of life history diversity in population trajectories, population models need to incorporate within-population variation. Integrated population modeling (IPM) is a population modeling approach that offers several advantages for sharing information and propagating uncertainty across datasets. In this study, we developed an IPM for an endangered population of Chinook salmon ( Oncorhynchus tshawytscha ) in the Wenatchee River, Washington, USA, that accounts for diversity in juvenile life histories, spawning location, and return age. Our analysis revealed that diversity in the age of juvenile emigration from natal streams had a portfolio effect, resulting in a 20% reduction in year-to-year variability in adult abundance in population projections. Our population viability analysis suggests that management interventions may be necessary to meet recovery goals, and our model should be useful for simulating the outcomes of proposed actions.

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USGS2024

Living with wildfire in Stemilt Basin, Chelan County, Washington: 2022 Data report

Homeowner wildfire risk mitigation and preparedness are important components of community wildfire readiness. This report presents data collected via rapid wildfire risk assessments to describe the parcel-level wildfire risk of properties within the Stemilt basin, Chelan County, Washington study area. The report also describes household survey data collected from homeowners in the study area, including their perspectives on wildfire risk, outreach preferences, mitigation and preparedness activities, and perceptions of community risk reduction strategies. Results may inform the wildfire risk outreach and programmatic efforts of the local fire department.

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USGS2024

Living with wildfire in Lake Wenatchee, Chelan County, Washington: 2022 Data report

Community wildfire readiness includes actions taken by residents, including wildfire risk mitigation at the parcel level and evacuation preparedness. This report presents results from two data collection efforts in the Lake Wenatchee Fire & Rescue service district in Chelan County, Washington: parcel level rapid wildfire risk assessments and household surveys sent to the owners of assessed parcels. Respondents reported that they were moderately aware of the risk of wildfire to their home, were discussing wildfire with their neighbors, and were taking action to reduce risk. There are gaps in respondents’ understanding of wildfire risk that might be addressed through educational outreach. Respondents were supportive of wildfire risk reduction strategies at the community level, including fuel treatments and policy options.

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USGS2024

How much trapping effort is needed for early detection of European green crab?

We present a case study using trapping data and species accumulation theory to assess the sampling effort needed to detect species that are rare in habitats sampled as part of the management of invasive European green crab Carcinus maenas on the coast of Washington State and Salish Sea shorelines, such as is desired for early detection of invasive species. In response to detections of green crab on the west coast of North America monitoring efforts, including early detection monitoring, have increased. The goal of invasive species early detection monitoring programs is to detect new infestations soon after introduction so that eradication and quarantine measures can be used to control their spread. However, detection of newly introduced invasive species often occurs after populations are large and well established. The ability to detect newly introduced invasive species is affected by sampling procedures, including how much effort is expended. To assess the level of trapping effort needed to detect green crab and other taxa when they are rare, we calculate sample-based rarefaction curves, total species richness, and estimates of sample completeness. We then use these estimates to describe the relationship between sampling effort and detection at two different spatial scales. Our results suggest that high probability early detection of green crabs or other rare taxa in many coastal waterbodies will require significantly more trapping effort than was expended in 2020. Our analyses further suggest that the effort required to provide for early detection was less at the site-specific spatial scale than at the waterbody scale. However, sample completeness at the site-specific spatial scale was negatively correlated with species richness. Current efforts to look for new green crab populations and to manage existing populations provide an opportunity to look for other invasive organisms that may establish in similar habitats.

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USGS2024

River channel response to the removal of the Pilchuck River Diversion Dam, Washington State

In August 2020, the 3-m tall Pilchuck River Diversion Dam was removed from the Pilchuck River, allowing free fish passage to the upper third of the watershed for the first time in over a century. The narrow, 300-m long impoundment behind the dam was estimated to hold 4,000–7,500 m 3 of sand and gravel, representing less than one year's typical bedload flux. Repeat cross section surveys, stage sensors, and time-lapse cameras were used to document the physical channel response over the first year following dam removal. A total of 7,400 m 3 (effectively 100%) of impoundment sediment was eroded in the first year, with 25% accomplished by manual regrading during dam removal. Most river-caused erosion occurred during a sequence of modest flows in October 2020. Downstream deposition totaled 4,300 m 3 , predominately filling in the first 100 m downstream of the dam site. Deposition tapered below detectable levels within 350 m, and most downstream channel adjustments occurred before November 2020. Multiple high flows after December 2020 caused little upstream or downstream change. The physical river response to this dam removal then appears to have been largely accomplished within several months by modest flows, consistent with pre-removal modeling and observations from other regional dam removals. Efficient sediment evacuation was likely aided by the narrow and steep-walled impoundment geometry. Our observations support existing guidance that the physical river response to small dam removals is typically rapid and modest; the benefits of removal may then often be gained with minimal negative downstream geomorphic impacts.

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USGS2024

Spatial and temporal surveys of salmon environmental DNA (eDNA) in a Seattle urban creek

Seattle Public Utilities (SPU) has a history of conducting traditional fish surveys in urban streams of Seattle, Washington. Limited staff resources have reduced SPU's capacity to monitor fish, and environmental DNA (eDNA) was recognized as an alternative survey method that could potentially improve the efficiency and capacity of SPU-sponsored fish surveys. We performed spatiotemporal surveys of eDNA to assess occupancy and distribution of Chinook Salmon ( Oncorhynchus tshawytscha ), Coho Salmon ( O . kisutch ), and Coastal Cutthroat Trout ( O . clarkii clarkii ) in Thornton Creek, Seattle, between October 2018 and December 2020. Peak Chinook and Coho eDNA detections occurred in October and October–November, respectively, coinciding with expected adult return time. Chinook and Coho eDNA was detected in May at the time when juveniles outmigrate through the Lake Washington basin. Coastal Cutthroat Trout eDNA was widespread and detected at high rates across seasons, reflecting their ubiquitous distribution. Results from multiscale occupancy modeling suggested that distance upstream affected site-level occupancy probabilities for adult Chinook, but not Coho. Model results also suggested that the probability of Coho and Chinook eDNA occurring in water samples was affected by survey year. Finally, model results suggested that the probability of detecting Chinook eDNA in PCR technical replicates was affected by survey year and collection day but detection of Coho eDNA was only affected by collection day. This study indicates eDNA surveys are effective for assessing distribution and occupancy of salmonids in Seattle's urban streams. Integrating eDNA surveys into urban stream monitoring programs can help alleviate the burden of limited assets facing many resource managers.

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USGS2024

Current and future potential ecosystem services of the Nisqually River Delta: An assessment approach for Puget Sound estuaries and USFWS coastal refuges

The Nisqually River Delta, located in South Puget Sound, contains a rich mosaic of different coastal habitat types. The goal of this project was to quantify ecosystem services — benefits that wildlife or ecosystems provide to people — that are priorities for the Billy Frank Jr. Nisqually National Wildlife Refuge, the Nisqually Indian Tribe, and the surrounding communities. We modeled how change in these habitats from sea level rise (SLR) or management activities like restoration could affect ecosystem services in the future. We focused on changes to three main ecosystem services: soil carbon accumulation, birdwatching visitation, and juvenile Chinook salmon growth rates, which served as a proxy for fishery production. A habitat and carbon model projected that after 100 years, most high salt marsh would remain with < 1m SLR, but a substantial area would convert to low salt marsh and mudflat with ≥ 1m SLR. Total carbon accumulation would plateau or decline with ≥ 1m SLR, yet economic value of carbon accumulation would continue to rise over time, suggesting that the value of this ecosystem service is resilient to SLR. Birdwatching visitation was greatest in winter months and was positively related to area of forested wetland, emergent wetland, aquatic vegetation bed (e.g., eelgrass) and mudflat and open access (areas freely accessible to the public). Increases in forested wetland may lead to greater increases in visitation compared to other habitat types. All three ecosystem services increased with increases in forested wetland and emergent wetland, and tradeoffs among services occurred with increases in aquatic vegetation bed and mudflat. While both prey-rich salt marshes and eelgrass meadows facilitate salmon growth, loss of salt marsh led to declines in juvenile salmon weight. In conversation with USFWS managers, we identified practical ways to incorporate ecosystem services into adaptive management frameworks that support climate adaptation decision making. Our study illustrated how accounting for ecosystem services helps managers make decisions that greatly benefit wildlife and people, communicate the societal value of decisions, and increase local engagement and participation.

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USGS2023

Prediction of the probability of elevated nitrate concentrations at groundwater depths used for drinking-water supply in the Puget Sound basin, Washington, 2004–19

The Puget Sound basin encompasses the 13,700-square-mile area that drains to the Puget Sound and the adjacent marine waters of Washington State. Well more than 4 million people live within the basin, with numbers continuing to increase, who rely on the basin’s natural resources including groundwater. The Puget Sound Partnership was created by a Washington State statute to implement a science-based recovery of the Puget Sound to help address impacts to these resources. As part of the recovery, the partnership developed the Puget Sound Vital Signs as measures of ecosystem health that guide the assessment of progress toward Puget Sound recovery goals. The Puget Sound Partnership Leadership Council adopted a Drinking Water Vital Sign associated with human health and quality of life, recognizing certain indicators as integral to the sustainability of Puget Sound recovery efforts. One such Vital Sign indicator was the vulnerability of groundwater throughout the aquifers of the Puget Sound basin to elevated nitrate concentrations as defined by the probability of exceeding 2 milligrams/liter (mg/L) at a specific location and well depth. The U.S. Geological Survey (USGS) led the effort to characterize groundwater vulnerability. For this study, groundwater vulnerability refers to a probability with which a contaminant applied at or near the land surface can migrate to the aquifer of interest for a given set of land-use practices. Nitrate concentration data were selected for evaluation because elevated nitrate concentrations are typically caused by anthropogenic activities and have been associated with deleterious impacts on human health. To identify groundwater vulnerability to elevated nitrate concentrations, logistic regression was used to relate anthropogenic (human associated) and natural variables to the occurrence of elevated nitrate concentrations in untreated groundwater from large public water supply system wells found within the Washington State Department of Health Sentry database. Variables that were analyzed included well depth, soil hydraulic conductivity, precipitation, population density, fertilizer application amounts, and land-use types. Statistically significant models that predicted the probabilities of groundwater nitrate concentrations greater than 2 mg/L based on the predictor variables were created for the time periods 2000–04, 2005–09, 2010–14, and 2015–19. For all time periods, well depth and a measure of the abundance of urban and agricultural land over or near the well consistently helped explain the vulnerability of the well to elevated nitrate concentrations defined as a probability of exceeding 2 mg/L of nitrate. Precipitation and (or) soil hydraulic conductivity were also important predictor variables in the models. The models for each time period were used to create maps of groundwater vulnerability at 150- and 300-foot depths throughout the Puget Sound basin. As expected, the most vulnerable locations were associated with shallower well depths and increased agriculture and urban land cover. Across all four time periods, groundwater vulnerability throughout the Puget Sound was low, with probabilities of exceeding 2 mg/L concentrations of nitrate at depths at 150 and 300 feet typically less than 50 percent. Results also found a slight decrease in probabilities of elevated nitrate concentrations throughout the basin over time. More specifically, additional statistical tests found that groundwater with probabilities of less than about 60 percent declined from 2000 to 2019 and represented more than 75 percent of the modeled Puget Sound basin aquifer. Wells with greater than 60 percent probability increased over the same time period but represented only about 25 percent of the aquifer. The maps and statistical analysis presented in the study provide valuable and informative evaluation of the vulnerability of groundwater in the Puget Sound basin to elevated nitrate concentrations. The probability maps do not represent measured nitrate concentrations in groundwater, but rather they present the probability that nitrate concentrations exceed 2 mg/L. The models and predictions from this study are a viable indicator for the Puget Sound Partnership’s Healthy Human Population—Drinking Water Vital Sign. The logistic regression modeling approach presented here benefits water managers by allowing them to assess temporal trends in a range of probabilities, explore vulnerability changes as new regional land cover and anthropogenic data are generated, and distinguish vulnerabilities at different depths within the aquifer.

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USGS2023

Applying intrinsic potential models to evaluate salmon (Oncorhynchus spp.) introduction into main-stem and tributary habitats upstream from the Skagit River Hydroelectric Project, northern Washington

We assessed habitat suitability for salmonids across selected tributaries upstream from three hydroelectric dams on the upper Skagit River in Whatcom County, northern Washington. We used NetMap, a commercial toolset within the ArcMap geographic information system (GIS), to analyze stream attributes based upon a synthetic stream channel network derived from digital elevation models. The GIS-derived stream attributes—including gradient, bankfull width, valley width index, elevation, and stream flow—allowed us to examine the spatial distribution and relative quality of spawning and rearing habitat for salmonids based on existing intrinsic potential (IP) models. As a first step, we created maps of potential anadromous fish distribution by identifying potential migration barriers within the synthetic stream network. Next, we applied a suite of existing IP models for steelhead, coho, and Chinook salmon ( Oncorhynchus mykiss , O. kisutch , and O. tshawytscha , respectively) to estimate low, medium, and high IP habitat for each species. Three different IP models were used for each species, based on species preference curves from populations from coastal Oregon, northern California, Alaska, and western Washington. We found that at least 25 tributaries that were greater than third order and contained habitat with the potential for anadromous fish, totaling about 470 river kilometers in 4,453 synthetic stream reaches averaging about 100 meters (m) in length. The IP of each of these reaches was calculated and placed into low, medium, and high IP categories. For Chinook salmon, the only stream with significantly (in other words, greater than 1 kilometer [km]) high IP reaches was the upper Skagit River upstream from Ross Lake reservoir in Canada, upstream from the third dam in the hydroelectric system. There were differences among the three models evaluated, with the model derived for the lower Skagit River showing more high and medium IP habitat than the other two models that were designed for the Columbia River Basin. For coho salmon, all three models showed similar results favoring medium IP over low and high IP habitat. Of the 3 species examined with existing IP models, steelhead had the most habitat rated as high IP with 19 targeted tributaries showing greater than 1 km of high intrinsic potential habitat.

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USGS2023

Nisqually River Delta—Humans and nature benefiting together

Introduction This is a brochure created in partnership with the U.S. Geological Survey (USGS), the Nisqually Indian Tribe, and the Billy Frank Jr. Nisqually National Wildlife Refuge. Designed for a public audience, the brochure describes the history of the Nisqually Indian Tribe, the ecology of the delta, the resources and recreational opportunities available for Refuge visitors, future challenges posed by climate change, and opportunities to protect wildlife and their habitats in the future.

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USGS2023

A review of natural and managed revegetation responses in two de-watered reservoirs after large dam removals on the Elwha River, Washington, USA

Large dam removals are increasing in frequency and the response of natural and managed revegetation is a critical consideration for managed restoration of dewatered reservoir landscapes post dam removal. The removal of two large dams on the Elwha River in 2011-2014 provides insight into reservoir revegetation. We review literature and datasets from 2012 through 2018, 1-6 years since reservoir dewatering, to compare pre-dam removal predictions on the Elwha to post-dam removal of natural revegetation, managed revegetation effects and invasive non-native vegetation response. Pre-dam removal hypotheses about natural revegetation did not predict species performance on reservoir sediments, seed rain patterns, or seed bank response. Sediment texture and landform affected multiple aspects of revegetation, including vegetation cover, species richness, woody stem densities and species composition. Reservoir drawdown timing influenced species composition and seedling densities. Predictions about managed revegetation effects were mixed. Planting trees and shrubs did not accelerate woody cover but did increase species richness. Seeding reduced non-native vegetation frequency and species richness, had no effect on vegetation cover on fine sediments, but increased vegetation cover on coarse sediments. Planting trees and shrubs during drawdown appeared to result in higher survival rates compared to plantings installed 1+ years post drawdown. Seeding Lupinus rivularis (riverbank lupine) on coarse sediments was successful and increased foliar nitrogen in planted conifers. Invasive non-native vegetation was correctly predicted to be more abundant in the Aldwell reservoir but did not preclude native species establishment in either reservoir, likely due to rapid establishment of native species and robust management that occurred before, during and after dam removal.

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USGS2023

Survival implications of diversion entrainment for outmigrating juvenile Chinook Salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss)

Efforts to ameliorate negative effects of diversion dams on aquatic species of concern are important in rivers where water withdrawal supports agricultural economies and are likely to become increasingly important with impending climate change. A multiyear study was conducted to evaluate the survival consequences of diversion dam passage for juvenile Chinook Salmon ( Oncorhynchus tshawytscha ) and steelhead ( O. mykiss ) in the highly managed Yakima River, Washington. Canal entrainment and passage were evaluated at four diversion dams encountered by seaward migrating juvenile salmon and steelhead. Fish pass dams via spillbays or enter canals with downstream fish-screening facilities designed to collect entrained fish and return them to the mainstem river. Percent entrainment into canals was substantial (6–59%) at three of the four diversion dams studied, and entrainment probability was positively associated with the proportion of streamflow diverted into canals. Survival probability estimates for groups of tagged fish that were entrained into canals were lower than survival probability estimates for tagged fish that passed through spillbays on the dams. Absolute differences in survival probabilities between routes ranged from 0.099 to 0.369, demonstrating that canal entrainment reduced survival of outmigrating juvenile Chinook Salmon and steelhead. We also found that entrainment resulted in migration delays, which could further affect survival because fish are increasingly exposed to predation and decreased water quality as water temperature increases throughout the migration season. These results highlight the need to limit entrainment of juvenile salmon and steelhead at diversion dams in rivers where salmon recovery is important.

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