Washington Population Research Articles

The influence of latitude, geographic distance, and habitat discontinuities on genetic variation in a high latitude montane species

Examining the factors that influence contemporary genetic patterns is important given the alarming rate at which natural environments are changing. In particular habitat fragmentation and climate change are expected to influence the distribution and diversity of natural populations. In this study we used both mitochondrial control region (mtDNA) and microsatellite data to answer the following questions about genetic diversity and divergence in mountain chickadees (Poecile gambeli) a resident bird species in western North America: (1) Do populations exhibit similar levels of genetic diversity across the range? (2) What is the genetic affinity of western populations in Oregon and Washington? (3) Do genetic patterns exhibit isolation by distance, or are genetic patterns more heavily influenced by habitat discontinuity? We tested the effects of isolation by distance and habitat distribution on genetic structure by analyzing 266 samples from 17 sites across western Canada and the United States. We found a near significant relationship between genetic diversity and latitude, however, our results indicate that overall, latitude is not a strong predictor of genetic diversity. Our analyses of populations in Oregon and Washington revealed a mismatch between patterns detected with mtDNA and microsatellite data. In particular, Washington clustered with the Coast Range/Cascades/Rocky Mountain mtDNA group, but with populations in southern Oregon/California based on microsatellite data. These results suggest the presence of a contact zone in Washington between the two mtDNA clades Coast Range/Cascades/Rocky Mountain and southern Oregon/California clades. Finally, our study revealed a greater effect of isolation by distance than isolation by habitat for both mtDNA and microsatellite data. Overall the isolation by distance signal was greater for mtDNA than microsatellite patterns. The greater signal of isolation by distance on mtDNA patterns likely reflects the strong effects of Pleistocene glaciations in shaping genetic patterns in western North America.

MORTALITY TRENDS IN NORTHERN SEA OTTERS ( ENHYDRA LUTRIS KENYONI) COLLECTED FROM THE COASTS OF WASHINGTON AND OREGON, USA (2002-15).

During 2002-15 we examined the causes of mortality in a population of northern sea otters ( Enhydra lutris kenyoni). Beachcast sea otters were collected primarily from the US coast of Washington. Although there are no permanent sea otter residents in Oregon, several beachcast otters were collected from the Oregon coast. Infectious diseases were the primary cause of death (56%) for otters we examined. Sarcocystosis was the leading infectious cause of death (54%) and was observed throughout the study period. Some infectious diseases, such as morbilliviral encephalitis and leptospirosis, were documented for a limited number of years and then not detected again despite continued testing for these pathogens in necropsied animals. Trauma was the second most common cause of death (14%) during the study period. The continued stable growth of the Washington population of otters suggests they are able to tolerate current mortality rates.

“The Servant Campaigns”: African American Women and the Politics of Economic Justice in Washington, D.C., in the 1930s

When Franklin D. Roosevelt, a Democrat, was elected president in 1932, most African Americans did not support him since they were still loyal to the Republican Party. Moreover, New Deal policies, especially the Social Security Act in 1935, excluded farmers and domestics, and thus, most African Americans. One of the people who encouraged black voters to switch to the Democratic Party was Elizabeth McDuffie, a black servant in the Roosevelt White House. In the 1936 election, McDuffie went on the campaign trail and toured Chicago, Cleveland, Springfield, and St. Louis. As a domestic servant, McDuffie was a familiar face to southern migrants, and she convinced many black voters to switch to the Democratic Party. After her campaign tour concluded, McDuffie became acquainted with the large black population in Washington, D.C. McDuffie worked alongside middle-class activists to increase economic opportunities for women workers by sponsoring training programs for servants. But, as this article demonstrates, most black servants did not want training programs; they desired higher wages, better jobs, and inclusion in the Social Security Act. Working-class women in Washington wrote letters to the newspaper and in 1938, 10,000 rioted for jobs as federal charwomen, jobs that paid higher wages and offered savings for retirement. After McDuffie witnessed these events, she became a vocal critic of the limitations of New Deal programs while continuing to praise Roosevelt and the Democratic Party. This article argues that Elizabeth McDuffie’s career in Washington illuminates the contradictions of New Deal politics for black women workers.

Life History Observations of Adfluvial Chinook Salmon prior to Reintroduction of Anadromous Salmonids

AbstractPacific salmon Oncorhynchus spp. vary in life history and degree of anadromy, but information on populations inhabiting only freshwater throughout their life cycle is limited. We confirmed the presence of a self‐sustaining population of adfluvial Chinook Salmon O. tshawytscha upstream of century‐old hydroelectric dams in the Skokomish River system, Washington. Snorkel, redd, and juvenile‐trapping surveys revealed their life history attributes prior to planned reintroductions of anadromous salmonids above the dams. Adult Chinook Salmon in Lake Cushman (a reservoir) were large‐bodied fish (mean length = 610 mm; mean weight = 5.4 kg), up to 4 years of age, and migrated into the inlet river to spawn in October and November. Annual peak counts of adult spawners were chronically low (35 or less) based on interannual snorkel surveys since 1994. Chinook Salmon parr (n = 780; mean length = 105 mm) of a single cohort were captured (June–August) at the upper dam and had faded parr marks and bright, silvery coloration typical of smolts. Our study confirmed that Chinook Salmon reared and reproduced exclusively in freshwater and suggested a life history pattern most closely resembling anadromous fall‐run Chinook Salmon. We reviewed annual hatchery release records from 1926 to 2016 and found no evidence of Chinook Salmon being planted above the dams, in contrast to landlocked Chinook Salmon occurring in Oregon and California reservoirs. These adfluvial Chinook Salmon may be descendants of the native Skokomish River anadromous population, including fish from below the dam, and represent adaptations to the reservoir after dam construction. Lake Cushman Chinook Salmon are federally threatened, the only reported landlocked population in Puget Sound and coastal Washington, and may represent a unique evolutionary legacy worthy of protection.Received March 7, 2017; accepted July 5, 2017 Published online October 20, 2017

A Pilot Study of Reduced Olfactory Bulb Volume as a Marker of PTSD in Childhood Trauma-Exposed Adult HIV-Infected Patients.

Evidence suggests that olfactory bulb (OB), a key structure in odor processing, may also be involved in mechanisms of traumatic stress. In animals, chronic stress reduces OB plasticity, and olfactory bulbectomy results in stress-enhanced startle reflex and autonomic dysregulation. However, OB morphometry has not been adequately studied in the development of stress disorders following childhood trauma in humans. The researchers conducted a pilot study evaluating the relationships between OB volume, childhood trauma, and lifetime posttraumatic stress disorder (PTSD) in a sample of 16 HIV-positive individuals, 13 of whom were exposed to childhood trauma of 9 developed PTSD. Participants were recruited from a larger cohort of inner city-dwelling HIV-positive populations in Washington, DC. Mean OB volumes were significantly reduced when PTSD and non-PTSD groups were compared, p = .019, as well as when trauma-exposed PTSD-positive and trauma-exposed PTSD-negative groups were compared, p = .008. No significant difference was observed when trauma-exposed and nonexposed participants were compared. The association between PTSD and right OB volume remained strong p = 0.002 after adjusting for group differences in sex, age, depression, hippocampal volume, and total intracranial volume. Because this study is limited by small sample size, further elucidation of relationships between OB, trauma, and PTSD should be investigated in larger cross-sectional and prospective studies and in diverse cohorts.

Declining patterns of Pacific Northwest steelhead trout (Oncorhynchus mykiss) adult abundance and smolt survival in the ocean

Examination of population abundance and survival trends over space and time can guide management and conservation actions with information about the spatial and temporal scale of factors affecting them. Here, we analyzed steelhead trout (anadromous Oncorhynchus mykiss) adult abundance time series from 35 coastal British Columbia and Washington populations along with smolt-to-adult return (smolt survival) time series from 48 populations from Washington, Oregon, and the Keogh River in British Columbia. Over 80% of the populations have declined in abundance since 1980. A multivariate autoregressive state-space model revealed smolt survival four groupings: Washington and Oregon coast, lower Columbia River, Strait of Juan de Fuca, and Puget Sound – Keogh River populations. Declines in smolt survival rates were seen for three of the four groupings. Puget Sound and Keogh River populations have experienced low rates since the early 1990s. Correlations between population pairs’ time series and distance apart illustrated that smolt survival rates were more positively correlated for proximate populations, suggesting that important processes, including those related to ocean survival, occur early in the marine life of steelhead.

Between Hot Rocks and Dry Places: The Status of the Dixie Valley Toad

In Dixie Valley, Nevada, an isolated population of toads has been the subject of proactive conservation measures by the Nevada Department of Wildlife and the U.S. Fish and Wildlife Service since 2008 due to concerns about potential habitat degradation resulting from exploitation of nearby geothermal energy resources. These toads appear to belong within the Anaxyrus boreas species group but are commonly referred to as Dixie Valley toads (DVTs). The DVT is currently confined to an extremely narrow habitat range (370 ha) that is geographically isolated from any other A. boreas population. In this study, genetic variations in mitochondrial genes and 11 microsatellite loci were used to assess the affinities of DVTs in relation to members of the A. boreas species group. We compared results from DVTs with previously published data spanning much of the range of A. boreas in the United States and new data from a nearby toad population within Dixie Valley. Data from both mitochondrial DNA and microsatellites placed DVTs inside the A. boreas species group. In particular, DVTs fell into a cluster of A. boreas from Washington and California, along with other species from the A. boreas species group, namely A. nelsoni, A. canorus, and A. exsul. Genetic differentiation of DVTs was lowest between A. boreas populations in Washington and California. However, allele frequencies were significantly different between DVTs and all other populations, including a nearby locality within Dixie Valley. This genetic differentiation, along with the DVT's geographical isolation and restricted habitat, warrants recognition of the DVT as a distinct management unit.

Does Choice of Influenza Vaccine Type Change Disease Burden and Cost-Effectiveness in the United States? An Agent-Based Modeling Study.

Offering a choice of influenza vaccine type may increase vaccine coverage and reduce disease burden, but it is more costly. This study calculated the public health impact and cost-effectiveness of 4 strategies: no choice, pediatric choice, adult choice, or choice for both age groups. Using agent-based modeling, individuals were simulated as they interacted with others, and influenza was tracked as it spread through a population in Washington, DC. Influenza vaccination coverage derived from data from the Centers for Disease Control and Prevention was increased by 6.5% (range, 3.25%-11.25%), reflecting changes due to vaccine choice. With moderate influenza infectivity, the number of cases averaged 1,117,285 for no choice, 1,083,126 for pediatric choice, 1,009,026 for adult choice, and 975,818 for choice for both age groups. Averted cases increased with increased coverage and were highest for the choice-for-both-age-groups strategy; adult choice also reduced cases in children. In cost-effectiveness analysis, choice for both age groups was dominant when choice increased vaccine coverage by ≥3.25%. Offering a choice of influenza vaccines, with reasonable resultant increases in coverage, decreased influenza cases by >100,000 with a favorable cost-effectiveness profile. Clinical trials testing the predictions made based on these simulation results and deliberation of policies and procedures to facilitate choice should be considered.

An Innovative, Mobile-health Enhanced, Peer-counseling Program to Improve Breastfeeding among Low-income, Minority Populations in Washington, DC

An Innovative, Mobile-health Enhanced, Peer-counseling Program to Improve Breastfeeding among Low-income, Minority Populations in Washington, DC

Access Denied: African Americans and Access to End-of-Life Care in Nineteenth-Century Washington, D.C.

In 1959, construction workers uncovered skeletal remains associated with two 19th-century African American and Quaker cemeteries in Washington, D.C. Thirty years later, biological anthropologists at the Smithsonian Institution analyzed a small sample of the remains and concluded that “the overall health pattern of this group [from the Mt. Pleasant Plains Cemetery] was one of good health in comparison to other blacks and many whites of the time” (Mann and Krakker 1989:21). However, recognizing the limitation of small sample size for bioarchaeological study (MNI=14), researchers were unable to make general inferences about African American mortality and morbidity in the District of Columbia. Building upon this earlier bioarchaeological analysis, this study uses demographic data from the death records of 7,237 individuals interred at the Mt. Pleasant Plains Cemetery between 1874 and 1890 to infer variability in access to healthcare amongst African Americans in the late 19th century. The results demonstrate that, for African American women, access to end-of-life care (EoLC) in hospitals was in part contingent upon employment. Thus, young African American women less than 16 years of age represent one of the most vulnerable populations in 19th-century Washington, D.C., as they lacked general access to EoLC in hospitals. In addition to exploring this gendered component to healthcare, this study also demonstrates the diverse health experiences of African Americans and argues that archaeologists can adhere to ethical principles that discourage archaeological excavations while still addressing important research questions.

Engaging Community Leaders in the Development of a Cardiovascular Health Behavior Survey Using Focus Group-Based Cognitive Interviewing.

Establishing the validity of health behavior surveys used in community-based participatory research (CBPR) in diverse populations is often overlooked. A novel, group-based cognitive interviewing method was used to obtain qualitative data for tailoring a survey instrument designed to identify barriers to improved cardiovascular health in at-risk populations in Washington, DC. A focus group–based cognitive interview was conducted to assess item comprehension, recall, and interpretation and to establish the initial content validity of the survey. Thematic analysis of verbatim transcripts yielded 5 main themes for which participants (n = 8) suggested survey modifications, including survey item improvements, suggestions for additional items, community-specific issues, changes in the skip logic of the survey items, and the identification of typographical errors. Population-specific modifications were made, including the development of more culturally appropriate questions relevant to the community. Group-based cognitive interviewing provided an efficient and effective method for piloting a cardiovascular health survey instrument using CBPR.

STRESS LEVELS IN CAPTURED RIVER OTTERS (LONTRA CANADENSIS) DECREASED AFTER TRANSPORTATION TO REINTRODUCTION SITES.

The level of stress that animals endure during capture, handling, transportation, and release processes is a major concern of animal reintroduction projects. Animals under chronic stress are more susceptible to disease and other deleterious issues that could reduce their survival in a new environment. Northern river otters ( Lontra canadensis ) have been reintroduced in 22 states in the United States and may be susceptible to developing chronic stress during the reintroduction process. We assessed stress levels in five river otters captured from wild populations in Washington, held in captivity for up to 21 days, and then transported to New Mexico for reintroduction. Glucocorticoid levels in fecal samples of all otters tested decreased from when they were held captive in Washington to the time of release. This outcome suggests that habituation to captivity before transport and release may serve to minimize the likelihood of an otter being released while experiencing a potentially burdensome level of stress.

Community Engagement to Optimize the Use of Web-Based and Wearable Technology in a Cardiovascular Health and Needs Assessment Study: A Mixed Methods Approach.

BackgroundResource-limited communities in Washington, D.C. have high rates of obesity-related cardiovascular disease in addition to inadequate physical activity (PA) facilities and limited Internet access. Engaging community members in the design and implementation of studies to address these health disparities is essential to the success of community-based PA interventions.ObjectiveThe objective of the study was to use qualitative and quantitative methods to evaluate the feasibility and acceptability of PA-monitoring wristbands and Web-based technology by predominantly African American, church-based populations in resource-limited Washington, D.C. neighborhoods.MethodsTo address cardiovascular health in at-risk populations in Washington, D.C., we joined community leaders to establish a community advisory board, the D.C. Cardiovascular Health and Obesity Collaborative (D.C. CHOC). As their first initiative, the Washington, D.C. Cardiovascular Health and Needs Assessment intends to evaluate cardiovascular health, social determinants of health, and PA-monitoring technologies. At the recommendation of D.C. CHOC members, we conducted a focus group and piloted the proposed PA-monitoring system with community members representing churches that would be targeted by the Cardiovascular Health and Needs Assessment. Participants (n=8) agreed to wear a PA-monitoring wristband for two weeks and to log cardiovascular health factors on a secure Internet account. Wristbands collected accelerometer-based data that participants uploaded to a wireless hub at their church. Participants agreed to return after two weeks to participate in a moderated focus group to share experiences using this technology. Feasibility was measured by Internet account usage, wristband utilization, and objective PA data. Acceptability was evaluated through thematic analysis of verbatim focus group transcripts.ResultsStudy participants (5 males, 3 females) were African American and age 28-70 years. Participant wristbands recorded data on 10.1±1.6 days. Two participants logged cardiovascular health factors on the website. Focus group transcripts revealed that participants felt positively about incorporating the device into their church-based populations, given improvements were made to device training, hub accessibility, and device feedback.ConclusionsPA-monitoring wristbands for objectively measuring PA appear to be a feasible and acceptable technology in Washington, D.C., resource-limited communities. User preferences include immediate device feedback, hands-on device training, explicit instructions, improved central hub accessibility, and designation of a church member as a trained point-of-contact. When implementing technology-based interventions in resource-limited communities, engaging the targeted community may aid in early identification of issues, suggestions, and preferences.ClinicalTrialTrial Registration: ClinicalTrials.gov NCT01927783; https://clinicaltrials.gov/ct2/show/NCT01927783 (Archived by WebCite at http://www.webcitation.org/6f8wL117u)

Consequences for conservation: population density and genetic effects on reproduction of an endangered lagomorph.

Understanding reproduction and mating systems is important for managers tasked with conserving vulnerable species. Genetic tools allow biologists to investigate reproduction and mating systems with high resolution and are particularly useful for species that are otherwise difficult to study in their natural environments. We conducted parentage analyses using 19 nuclear DNA microsatellite loci to assess the influence of population density, genetic diversity, and ancestry on reproduction, and to examine the mating system of pygmy rabbits (Brachylagus idahoensis) bred in large naturalized enclosures for the reintroduction and recovery of the endangered distinct population in central Washington, USA. Reproductive output for females and males decreased as population density and individual homozygosity increased. We identified an interaction indicating that male reproductive output decreased as genetic diversity declined at high population densities, but there was no effect at low densities. Males with high amounts (> 50%) of Washington ancestry had higher reproductive output than the other ancestry groups, while reproductive output was decreased for males with high northern Utah/Wyoming ancestry and females with high Oregon/Nevada ancestry. Females and males bred with an average of 3.8 and 3.6 mates per year, respectively, and we found no evidence of positive or negative assortative mating with regards to ancestry. Multiple paternity was confirmed in 81% of litters, and we report the first documented cases of juvenile breeding by pygmy rabbits. This study demonstrates how variation in population density, genetic diversity, and ancestry impact fitness for an endangered species being bred for conservation. Our results advance understanding of basic life history characteristics for a cryptic species that is difficult to study in the wild and provide lessons for managing populations of vulnerable species in captive and free-ranging populations.

Triaging Psychiatric Care: Risk Assessment Construction and Validation for Washington's Involuntary Treatment and Forensic Commitment Populations.

There is a growing need in Washington to triage patients being considered for inpatient treatment. There has previously been no risk assessment normed to persons with mental illness in the State of Washington. The Static Risk Assessment (SRA) is used in Washington to assess risk among offenders under State Department of Corrections supervision. The present study sought to create and validate a new risk assessment, the SRA for Mental Health Patients (SRA-MHP), for two mental health populations in Washington. A sample of 16,289 patients involuntarily committed due to being deemed dangerous or gravely disabled, as well as a sample of 8,713 forensic patients undergoing a competency evaluation to stand trial after being charged with a crime, was gathered to assess the utility in applying the SRA-MHP to persons with mental illness. Results indicate that the SRA-MHP has high predictive performance for these samples.

Biological and physical ocean indicators predict the success of an invasive crab, Carcinus maenas, in the northern California Current

An introduced population of European green crabs Carcinus maenas was estab- lished in San Francisco Bay (California, USA) prior to 1989. Subsequently, their larvae were likely carried northward into the embayments of Oregon, Washington (USA), and British Columbia (Canada) by the unusually strong Davidson Current during the winter of the El Nino of 1997� 1998. Since this colonizing event, green crabs in Oregon and Washington have persisted at low densities. In this study, we show that after the arrival of the strong founding year-class of 1998, sig- nificant recruitment to the Oregon and Washington populations has occurred, but only in 2003, 2005, 2006 and 2010. Warm winter water temperatures, high positive values of the Pacific Decadal Oscillation (PDO) and Multivariate ENSO (El Nino Southern Oscillation) indices in March, weak southward shelf currents in March and April, a late biological spring transition, and high abun- dance of subtropical copepods are all strongly correlated with strong year-classes. We hypothe- size that northward transport of larvae from California by coastal currents during warm winters is the mechanism by which the larvae are delivered to the Pacific Northwest. Among the best indi- cators of northward flow (and green crab recruitment) were the date of 'biological spring transi- tion', the sign of the PDO, and the biomass of southern copepod species, which indicate (1) stronger northward flow of coastal waters during winters, (2) relatively warm winters (sea surface temperature >10°C), which enable larvae to complete their development in the near-shore, and (3) coastal circulation patterns that may keep larvae close to shore, where they can be carried by tidal currents into estuaries to settle.

Microsatellite Variation of two Pacific Coast Drosophila suzukii (Diptera: Drosophilidae) Populations.

The vinegar fly, Drosophila suzukii (Diptera: Drosophilidae), is a recent invader in North America that has become a serious threat to small fruit production. It was first detected in California in 2008 and in Washington state in 2009. In this study, D. suzukii populations from the area of the original detection on California's central coast and from eastern Washington, the United States, were sampled over a 3-year period to determine genetic variation in both using microsatellite markers. Six different loci were successfully amplified and included in the analysis. These loci included nanos, elf1, antennapedia, mastermind, z600, and tenA. The population from eastern Washington was highly monomorphic with one locus, mastermind, having multiple alleles. There was greater genetic variation in the coastal California population with all loci having multiple alleles, with the exception of tenA. Owing to the relatively low levels of genetic variation in the eastern Washington population compared with the coastal California population, it appears that the D. suzukii population in the eastern Washington region has undergone a significant bottleneck.

Significant Reductions in Mortality in Hospitalized Patients with Systemic Lupus Erythematosus in Washington State from 2003 to 2011.

BackgroundSystemic lupus erythematosus (SLE or lupus) is an autoimmune multisystem disease. While a complete understanding of lupus’ origins, mechanisms, and progression is not yet available, a number of studies have demonstrated correlations between disease prevalence and severity, gender, and race. There have been few population based studies in the United StatesObjectivesTo assess temporal changes in demographics and hospital mortality of patients with lupus in Washington State from 2003 to 2011Study DesignThis study used data from the Healthcare Cost and Utilization Project (HCUP), a patient information database, and data from the Washington State census to study a group of patients in the state. Lupus hospitalizations were defined as any hospitalization with an ICD-9-CM diagnosis code for systemic lupus erythematosus. Regression analysis was used to assess the effect of calendar time on demographics and hospital outcomes.ResultsThere were a total of 18,905 patients in this study with a diagnostic code for lupus. The mean age of the group was 51.5 years (95% CI: 50.6-52.3) in 2003 and 51.3 years (95% CI: 50.6-52.0) in 2011. The population was 88.6% female. Blacks were 2.8 times more likely to have a lupus hospitalization than whites when compared to the Washington population. While hospital mortality decreased during this eight year period (3.12% in 2003 to 1.28% in 2011, p=0.001) hospital length of stay remained statistically unchanged at an average of 4.9 days during that eight year period. We found a significant decrease in annual hospital mortality over the study period [odds ratio(OR): 0.92 per year, 95% CI 0.88-0.96, P<0.001]. Hospital mortality was higher in males (2.6% male death to 1.8% female death)ConclusionsIn this large group of hospitalized lupus patients in Washington, hospital length of stay remained relatively stable over time but hospital mortality decreased by over 50% over the eight year study period.

Landscape-level analysis of mountain goat population connectivity in Washington and southern British Columbia

Habitat fragmentation and habitat loss diminish population connectivity, reducing genetic diversity and increasing extinction risk over time. Improving connectivity is widely recommended to preserve the long-term viability of populations, but this requires accurate knowledge of how landscapes influence connectivity. Detectability of landscape effects on gene flow is highly dependent on landscape context, and drawing conclusions from single landscape studies may lead to ineffective management strategies. We present a novel approach to elucidate regional variation in the relative importance of landscape variable effects on gene flow. We demonstrate this approach by evaluating gene flow between isolated, genetically impoverished mountain goat (Oreamnos americanus) populations in Washington and much larger, genetically robust populations in southern British Columbia. We used geneland to identify steep genetic gradients and then employed individual-based landscape genetics in a causal modeling framework to independently evaluate landscape variables that may be generating each of these genetic gradients. Our results support previous findings that freeways, highways, water, agriculture and urban landcover limit gene flow in this species. Additionally, we found that a previously unsupported landscape variable, distance to escape terrain, also limits gene flow in some contexts. By integrating geneland and individual-based methods we effectively identified regional limiting factors that have landscape-level implications for population viability.

Hispanic Population in Washington State: Demographic Change and Spatial Clustering

Hispanic population across the United States reflects rapid growth along with changing patterns of immigration. For example, persons of Hispanic origin constituted 12.5 percent of the total population in 2000, a figure that grew to an estimated 16.9% in 2012. The work presented here also represents recognition of Hispanic population distribution in areas not historically identified with those populations, including the State of Washington and the Pacific Northwest. The fact that Hispanic population in Washington expanded from 4.4 percent of total population in 1990 to 11.2 percent in 2010 justifies this attention. Literature discussing Hispanic/Latino immigration has emphasized the states that share a common border with Mexico from Texas to California, along with Colorado and Florida. Recent literature has also recognized Hispanic/Latino immigration and its impacts on communities in the Midwest and along the East Coast. Attention to the Pacific Northwest has been minimal, even though there is a long history of Hispanic/Latino immigration, settlement, and participation in the Pacific Northwest, linked particularly to agriculture in Washington and Oregon. This paper aims to begin to fill gaps in the literature on Hispanic populations in the Northwest by mapping and describing Hispanic population change in counties across the state of Washington since 1990. A further aim is to examine spatial clustering of Hispanic populations within the State at a more detailed (Census Block Group) level. This initial study is part of a broader research effort to identify population change and critical issues facing Hispanic residents in Washington and to develop initiatives for greater awareness and engagement of Hispanics in Latino community place-making.