Northwest Science 97(4)

Assessing the efficacy of a large-scale habitat conservation plan in western Washington, USA - Joshua S. Halofsky, Daniel C. Donato

Habitat conservation plans (HCPs) under the US Endangered Species Act have become an important conservation tool. For over two decades, the Washington State Department of Natural Resources (WDNR) has managed much of the State’s forested lands under one of the largest and longest-running single-entity HCPs in existence, seeking to integrate timber harvest and other social-ecological values mostly related to structurally complex, older forest habitats. Here, we examine trends in older forest conditions on western Washington WDNR-managed lands relative to HCP expectations, using publicly available spatial datasets to compare trends in older forest area and connectivity before (1986-1999) and after (1999-2017) HCP implementation. Trends in both attributes changed markedly between the pre- and post-implementation periods, varying strongly with management intensity. Since 1999, total older forest area (i.e., that meeting structural index/indicator thresholds) saw little net change (-38 ha·yr^-1, totaling -685 ha) across ~624,000 ha, but shifted spatially from WDNR’s most intensively managed lands (-843 ha·yr^-1) to conservation-designated lands such as riparian (+552 ha·yr^-1) and mixed (with both harvest and habitat objectives) upland (+253 ha·yr^-1) areas. Similarly, older forest connectivity declined on lands primarily managed for timber but increased on all other lands managed less intensively. So far, the decades since HCP implementation largely have been a time of landscape reorganization – positioning the landscape consistent with HCP intentions to meet timber objectives while developing older forest habitat in designated areas into the future. This work illustrates a method to evaluate policy implementation and the likelihood of achieving HCP expectations over time.

Elevational distributions of forest floor mosses and a test of competition at two elevations in western Oregon - Bruce McCune, Jeff Diez, Joseph LaManna, Matthew G. Betts

Factors controlling mosses on the forest floor in western North America are poorly understood. We examined elevational distributions for six of the most abundant large forest floor mosses; based on those distributions, a transplant experiment of two species evaluated if interspecific interactions can be mediated by climatic context. Mosses had species-specific elevational profiles, with Rhytidiopsis robusta more prominent at higher elevations, while Hylocomium splendens, Kindbergia oregana, Rhytidiadelphus loreus, and Rhytidiadelphus triquetrus, were more prominent at lower elevations. Homalothecium megaptilum was bimodal, peaking at middle and low elevations. We selected Rhytidiadelphus triquetrus and Rhytidiopsis for a transplant experiment, because each is prominent at different elevations and they are similar in stature. Moss mat squares cut from the forest floor at middle elevations were transplanted in single- or mixed-species pattern at two sites, one high and one low. We recorded changes in percent cover within the squares over one year as well as outgrowth onto bare soil and litter. Hypothesized relative species performances based on elevational distributions were mostly not supported. The low-elevation associated species (Rhytidiadelphus) outperformed the high-elevation species (Rhytidiopsis) at the high-elevation site, both in mixture and as monocultures. At the lower site, Rhytidiadelphus grew well in mixture, but the monocultures declined. Furthermore, Rhytidiopsis grew faster at low elevation than high, both in mixture and in monoculture, despite being more abundant at high elevations. Poor performance of both species at high elevations raises interesting questions about what factors limit moss mats in general at higher elevations in the Cascade Range.

Northwest Science 97(3)

Flower phenology, bumble bee foraging, and climate change in North Cascades mountain meadows - James R. Davis, T. Abe Lloyd, Anu Singh-Cundy

We conducted a five-year study (2015-2019) of flower phenology and insect flower-foraging in Heather Meadows in the northern portion of the North Cascades in Washington State. We recorded 70 species of eudicot forbs and shrubs on seven transects at elevations ranging from 1,260 meters to 1,582 meters. In a typical year, there was continuity of floral resources within each transect and across the elevational gradient for the duration of the growing season. Black huckleberry was a critically important forage resource for post-diapause queens as they established nests in spring, even as 98% of the meadow was under snow. Transects with the highest tree island cover had the largest number of foraging spring queens. The exceptionally early spring of 2015 made it a good analog of climate change predicted for this region toward the end of the century. In 2015, flowering was two to eight weeks early for a majority of species, while the duration of flowering increased for a few species and decreased substantially for others, leading to phenological reassembly. These findings preview the potential impacts of climate change on flowering plants and flower-foraging insects in mountain meadows in the Pacific Northwest and could help guide effective conservation.

The complete pre-print version of this article is available here. Below, Bombus melanopygus visits flowers at Heather Meadows during 2019 sampling (Figure 6a).

Resilient plant communities and increasing native forbs after wildfire in a southwestern Oregon oak shrubland - Scott R. Abella, Charles D. Schelz

Fire ecology in oak shrublands is among the least well understood for Pacific Northwest habitats. Following the 2018 Klamathon Fire, we examined the first three years of post-wildfire plant community change and measured soil properties in shrubland dominated by shrub-form Oregon white oak (Quercus garryana) in Cascade-Siskiyou National Monument, Oregon. Based on temporal change and comparison with unburned areas, burned oak shrubland communities displayed resiliency and at least transient increases in some native plants apparently benefiting from wildfire. Via oak resprouting and other native plants increasing, total native cover rapidly recovered in burned areas by the second post-fire year to not differ (P > 0.05) from unburned areas. Native species richness (25 m²) did not differ with burning any year while community evenness and diversity were usually highest in burned areas. Native plants associated with burned areas included the perennial grass blue wildrye (Elymus glaucus), the shrub Pacific serviceberry (Amelanchier alnifolia), and most abundantly forbs, such as the perennial Scouler’s hawkweed (Hieracium scouleri) and annuals such as slender clarkia (Clarkia gracilis). Cover of non-native plants on burned areas was not higher than on unburned areas within any year. After severe burning, the 0–5 cm mineral soil had the finest texture and highest bulk density. Overall, oak shrubland vegetation displayed rapid resilience to wildfire and native forbs at least transiently increased.

The complete pre-print version of this article is available here. In the image below (Figure S1), resprouting and regrowth of vegetation in a burned oak shrubland is evident, four years after the 2018 Klamathon Fire.

Spatial and Temporal Surveys of Salmon Environmental DNA (eDNA) in a Seattle Urban Creek - Carl O. Ostberg, Chapin Pier, Dorothy M. Chase, Russell W. Perry

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 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. Multiscale occupancy modeling suggested that distance upstream may have affected site-level occupancy probabilities for adult Chinook, but not Coho, that the probability of Coho and Chinook eDNA occurring in water samples was possibly influenced by survey year, and that the probability of detecting Chinook eDNA in PCR technical replicates was possibly affected by survey year and collection day but the probability of detecting Coho eDNA was only affected by 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 resources facing many resource managers.

The complete pre-print version of this article is available here.

Evaluating abiotic and biotic predictors of coastal giant salamander (Dicamptodon tenebrosus) populations in fish-bearing headwaters of the Oregon Coast Range - Nathaniel G. Neal, Ashley M. Sanders, Ashley A. Coble, Dana R. Warren

From British Columbia to northern California, coastal giant salamanders (Dicamptodon tenebrosus) are a dominant vertebrate predator in forested headwater streams. Though widespread, body condition and abundance of coastal giant salamanders can differ substantially among locations, provoking the question of which factors may influence this variation and to what degree habitat features versus biotic variables drive variability. In this study, we collected data on coastal giant salamander populations along with four biotic factors and eight abiotic factors across 24 different study streams adjacent to mature second-growth forests in western Oregon, USA. We used single and multi-parameter linear mixed-effects models to explore the factors individually and in combination to functionally represent alternative hypotheses accounting for variation in salamander biomass density, population density, and condition. We established a set of 25 models and employed Akaike’s Information Criterion (AIC) selection for comparison. We expected food resources and the abundance of coastal giant salamander competitors to have comparable and complementary influences with stream habitat metrics. However, biotic metrics did not appear in our top models. Two abiotic variables, pool area and substrate size, best predicted the biomass and population density of coastal giant salamanders across our study streams. Substrate size and pool area were negatively related to salamander density, in contrast to our expectations. Overall, our results suggest that habitat metrics in summer months influence the abundance and biomass density of coastal giant salamanders in western headwater streams, and therefore habitat availability warrants particular consideration in conservation efforts.

The complete pre-print version of this article is available here.

Contribution of log mat periphyton to benthic productivity at Spirit Lake, Mount St. Helens National Volcanic Monument, WA, USA - Avery Shinneman, Kena Fox-Dobbs, Emma Sevier, Angelica Luchetto, Jeremy Davis, James E. Gawel

Spirit Lake, in southwest Washington, USA, was dramatically changed as a result of the 1980 eruption of Mount St. Helens. The lake morphology was altered by debris flows and the water was sterilized of most living organisms. Trees felled by the lateral blast and subsequently washed into the lake comprise a floating log mat which now covers 20% of the lake’s surface area, providing a novel substrate for benthic productivity. By investigating the evolution of this volcanic landscape’s rapidly recovering aquatic ecosystem, our work specifically addresses the following questions related to the role of the floating log mat and associated benthic periphyton to sedimentary inputs of organic material: (1) Do patterns of log mat occupancy and related deposition of benthic periphyton correlate to spatial variation in organic sedimentary inputs? (2) How has benthic productivity changed over the lake’s 40-year history since the initial establishment of the log mat? To address these questions we analyzed biological and geochemical data derived from sampling the floating logs, sediment traps in the water column, a set of shallow sediment samples, and two sediment cores in areas of differing log mat occupancy. We used carbon and nitrogen elemental concentrations and stable isotope values of sediment organics to estimate the relative contributions of organic source materials (phytoplankton, macrophytes, periphyton) and diatom assemblages to infer information about changes through time. We found that spatial trends in sources of sediment organics corresponded to patterns of floating log mat occupancy, with higher contributions of periphyton derived biomass in areas with more frequent log presence. These results provide insight into the dynamic role of logmat-derived productivity in the ongoing recovery and evolution of the Spirit Lake ecosystem. Our findings also underscore the importance of understanding and managing coarse woody debris in oligotrophic lakes as a substrate for benthic primary productivity that supports the whole lake ecosystem.

The complete pre-print version of this article is available here. In the image below (Figure 2), surface sediment organic elemental and isotopic values - A: weight %C; B: weight %C:N ratio; C: δ13C value - are displayed for sampling locations across Spirit Lake.

Range extension of the non-native northern crayfish Faxonius virilis (Hagen, 1870) (Decapoda: Cambaridae) to British Columbia, Canada - Iain D. Phillips

Here I report the expansion of the northern crayfish Faxonius virilis (Hagen, 1870) (Decapoda: Cambaridae) into the Kootenay River Basin in southeastern British Columbia. Observation of this crayfish occurred in late summer 2023 at Moyie Lake, British Columbia based on active search collections from the littoral areas of the north end of the lake. I recorded 12 F. virilis individuals in only a few minutes of search, and they appear to be well established in the lake. As this region has been identified as having high invasion potential and risk for impact, further research on its current range in the area and effects on the local ecosystem will be important directions for further conservation work.

The complete pre-print version of this article is available here.

Northwest Science 97(2)

A survey of the diversity of butterflies in King County, Washington, USA - Benjamin Mous

A five-year field survey of the butterflies (Rhopalocera) of King County, Washington was conducted from August 2017 to August 2022 to compare the current butterfly fauna with historical records from the previous 140 years, and to expand our knowledge of butterfly diversity and distribution in this highly urbanized county. King County (5478 km²) is the most populous county in the state and has a wide variety of ecosystems, including three Level III ecoregions. For this survey, 73 sites were sampled for butterfly species occurrence, from sea level to 1700m (5600ft) elevation and with multiple sites in each ecoregion. The species recorded during this survey are compared to those recorded historically (pre-1996) from King County in Hinchliff (1996), as well as with the sum of currently known King County records. Notable changes in species diversity and the impacts of urbanization are discussed. All records and literature pertaining to the species not recorded during this survey but known to have occurred in King County are reviewed. A total of 63 species were recorded, including six species and one subspecies which were first records for King County. A total of 87.7% of the species recorded in Hinchliff (1996) and 85.1% of all recorded King County species were found during this survey. The history of the literature relating to the study of butterflies of King County is also discussed, as well as the notable species found during this survey.

The complete pre-print version of this article is available here. The butterfly species below (Figure 2) were new records for King County, Washington.

Documenting historical anchorworm parasitism of introduced warmwater fishes in the Willamette River Basin, Oregon - Elena Eberhardt, Christina Murphy, William Gerth, Peter Konstantinidis, Ivan Arismendi

Anchorworms (Lernaea spp.) are freshwater parasitic copepods that use a wide range of hosts. Yet, little is known about their prevalence, distribution, and which species are their primary fish hosts in the state of Oregon. Institutional fish collections serve as banks which allow investigators to look at historical fish specimens and ascertain their health status at the time of their collection. We examined 1,039 specimens collected between 1941 and 2016 from the Oregon State Ichthyology Collection to detect the presence of anchorworms on non-native warmwater fishes from the Willamette River Basin, Oregon. Adult female anchorworms were found on eleven of the seventeen fish species that we examined. The most infected species included Common Carp (Cyprinus carpio), Bluegill (Lepomis macrochirus), and Smallmouth Bass (Micropterus dolomieu). We suggest these introduced warmwater fishes can act not only as hosts, but also as potential reservoirs for these understudied parasites posing a potential risk for Endangered Species Act (ESA)-listed native fishes. Our findings reveal unique insights that will serve as a baseline to detect future changes in parasite loads in the Willamette River Basin.

The complete pre-print version of this article is available here.

Earthquake effects surveyed during the nineteenth century as ecological features of Chinookan tidelands - Brian F. Atwater, David K. Yamaguchi, Jessie K. Pearl

Lasting effects of a Cascadia earthquake in 1700 were documented during surveys of Chinookan tidelands near the mouth of the Columbia River between 1805 and 1868. The effects resemble estuarine consequences, near Anchorage, of the 1964 Alaska earthquake: fatal drowning of subsided meadows and forests by post-earthquake tides, rebirth of marshes and forests through post-earthquake sedimentation and uplift. Chinookan remains of killed forests were recorded by James Graham Cooper, John J. Lowell, and Cleveland Rockwell. Cooper, attached to a railroad survey and the Smithsonian Institution, wrote of redcedar stumps and trunks standing dead in tidal marshes of Shoalwater (now Willapa) Bay. Two such snags served as bearing trees for Lowell as he platted a Shoalwater Bay township under contract with the General Land Office. Rockwell, of the U. S. Coast Survey, flecked landward edges of tidal flats west of Astoria with symbols that evoke remains of a bygone spruce forest. The Lewis and Clark Expedition, while in that area in 1805–1806, mapped and puzzled over tideland vegetation that post-1700 succession helps explain.

The complete pre-print version of this article is available here. Below, from the township survey, redcedar trunks interpreted today as victims of a 1700 Cascadia earthquake (Figure 5d).

River channel response to the removal of the Pilchuck River Diversion Dam, Washington State - Scott W. Anderson, Brett Shattuck, Neil Shea, Catherine M. Seguin, Joe J. Miles, Derek Marks, Natasha Coumou

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 m³ 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 m³ (~100 %) of impoundment sediment was eroded in the first year, with 25 percent 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 m³, 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 steepwalled 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.

The complete pre-print version of this research note is available here. A 2020 image of the Pilchuck River Diversion Dam, 3-m tall and 18-m wide is displayed below (left), alongside graphical representation of channel volumetric change (July 6, 2020, to July 19, 2021) following dam removal.

Northwest Science 97(1)

Scanning the horizon for potential nonnative aquatic plant and algae arrivals to the Pacific Northwest – SOTS 2022 – Katherine E. Wyman-Grothem, Theresa A. Thom, Heidi L. Himes

To date, the Pacific Northwestern United States has experienced fewer nonnative species introductions than other parts of the country, presenting an opportunity to minimize future harm from invasive species by investing in prevention efforts. Horizon scanning for potential future invasive species provides foundational data for developing efficient prevention and early detection strategies. We gathered more than twenty Federal, State, Tribal, local government, University, and industry partners to provide input on priority geography, introduction pathways, and taxa for a horizon scan focused on the Pacific Northwestern United States. The scope of this initial effort included submerged or floating aquatic plants and algae that could be introduced to the region via movement of recreational boats. Watercraft inspection data were combined with climate matching analyses to identify “top donor regions” from which submerged or floating aquatic plants were most likely to arrive. We identified five aquatic plants as posing high risk to the Pacific Northwest on the basis of climate match and prior history of invasiveness in other locations: Carolina mosquitofern (Azolla caroliniana), crested mosquitofern (Azolla cristata), Indian swampweed (Hygrophila polysperma), wingleaf primrose-willow (Ludwigia decurrens), and water spangles (Salvinia minima). Another 21 species pose uncertain risk given available information. These results can be used to inform regulatory actions, improve training, and refine detection tools and strategies on a local, regional, and national level. More broadly, this horizon scan provides a template for future horizon scanning for other geographies, pathways, and taxonomic groups.

The complete pre-print version of this article is available here.

Human and wildlife use of mountain glacier habitat in western North America – Scott Hotaling, Jordan Boersma, Neil A. Paprocki, Alissa Anderson, Logan Whiles, Lucy Ogburn, Sophia Kasper, Catharine White, Daniel H. Thornton, Peter Wimberger

The global recession of glaciers and perennial snowfields is reshaping mountain ecosystems. Beyond physical changes to the landscape and altered downstream hydrology, the implications of glacier decline for biodiversity are poorly known. Before predictions can be made about how climate change will affect wildlife in glacier-associated ecosystems, a more thorough accounting of the role that glaciers play in species’ life histories is needed. In this study, we deployed an elevational transect of wildlife cameras along the western margin of the Paradise Glacier, a rapidly receding mountain glacier on the south side of Mount Rainier, WA, USA. From June to September 2021, we detected at least 16 vertebrate species (seven birds, nine mammals) using glacier-associated habitats over 770 trap nights. Humans, primarily skiers, were the most common species detected, but we also recorded 99 observations of wildlife (birds and mammals). These included three species of conservation concern in Washington: wolverine (Gulo gulo), Cascade red fox (Vulpes vulpes cascadensis), and white-tailed ptarmigan (Lagopus leucura). Collectively, our results reveal a rich diversity of wildlife using a single mountain glacier and adjacent habitat in the Pacific Northwest, emphasizing a largely overlooked risk of climate change to mountain biodiversity. We conclude by highlighting the global need for similar studies to better understand the true scale of biodiversity that will be impacted by glacier recession in mountain ecosystems.

The complete pre-print version of this article is available here. Camera trap images below (Figure 3) document the presence of three wildlife species of conservation concern in Washington.

Bull Trout Passage at Beaver Dams in Two Montana Streams – J. Marshall Wolf, Niall G. Clancy, Leo R. Rosenthal

Beaver (Castor canadensis) translocation and mimicry is an increasingly popular set of tools for process-based restoration of degraded streams. Previous studies indicate that spring-spawning salmonid fishes can pass beaver dams in higher proportions than fall-spawning species. Thus, restoration or mimicry of beavers in streams containing threatened, fall-spawning bull trout (Salvelinus confluentus) is of concern to many biologists. We evaluated bull trout passage at beaver dams in two Montana streams: Meadow Creek (East Fork Bitterroot River drainage) in summer 2020 and Morrison Creek (Middle Fork Flathead River drainage) from 1997 to 2011. In Meadow Creek, 16% of PIT-tagged bull trout which entered a large beaver dam complex were detected upstream of some dams, but no fish moved through the entire 1 km complex. The redds in Morrison Creek occurred below beaver dams in higher proportion than if random spawning-site selection had occurred. Redds were found above some beaver dams during all 9 years they were present. These results suggest that beaver dams can affect the movement of bull trout and that passage depends on the characteristics of individual dams and reach geomorphology. Our methods cannot distinguish between inhibition of fish movement and selection of beaver-created habitats by fish due to the limited data we had on spawning habitat. Therefore, we suggest future research on beaver restoration in streams with bull trout be carefully monitored and conducted in an adaptive framework. Comparing spawning-site selection and fish movement in streams with and without beaver may provide additional information.

The complete pre-print version of this article is available here. Below, the location of Meadow Creek and Morrison Creek (Figure 1), two streams in northwestern Montana, in which bull trout (Salvelinus confluentus) passage was studied.

Geoarchaeological Record of the AD 1700 Earthquake and Tsunami at the Salmon River Wet Site, Central Oregon Coast – Rick Minor, Alan R. Nelson

Coseismic subsidence is a major contributor to the scarcity of evidence in the archaeological record of prehistoric earthquakes along coasts of the Cascadia subduction zone. The stratigraphy of suddenly subsided tidal wetlands, in places overlain by tsunami-deposited sand, records a long history of great (magnitude 8–9) earthquakes over the last 3000–7000 years. The most recent of these great earthquakes and its accompanying high tsunami occurred on January 26, 1700. Here we synthesize geologic and archaeological investigations in the Salmon River estuary on the central Oregon coast. Following coastal subsidence of 1.4 ± 0.4 m during the AD 1700 earthquake, the site of a prehistoric settlement was submerged and covered by tsunami sand and tidal mud, creating an archaeological “wet site” subject to erosion in the tidal zone. Excavations in the last remnants of the eroding cultural deposits recovered evidence of a Tillamook Indian hunting camp occupied within a few hundred years before the AD 1700 earthquake. The Salmon River Wet Site, and similar submerged archaeological deposits in other estuaries, constitute rapidly disappearing evidence of coseismic subsidence during the AD 1700 earthquake along the Cascadia subduction zone on the north Pacific coast.

The complete pre-print version of this article is available here. Below, cultural remains are excavated from sediment in a riverbank (Figure 4b).

Reconsidering Subspecific Taxonomy of Odocoileus virginianus in Oregon and Washington – Winston. P. Smith, Leslie N. Carraway, Thomas A. Gavin, Jonathan A. Jenks

Two subspecies of white-tailed deer Odocoileus virginianus are recognized in the northwestern United States: O. v. leucurus (Douglas, 1829), and O. v. ochrourus Bailey, 1932. Historically, O. v. leucurus was common along the lower Columbia River and the name was applied to all populations in western Oregon as far south as Grants Pass. Today, O. v. leucurus is limited to populations along the Lower Columbia River with another in Douglas County, Oregon. Examination of 35 electrophoretic loci in 1988 did not support current subspecific taxonomy of O. virginianus in Oregon. Analysis of 18 cranial dimensions among three disjunct populations of O. virginianus in 2003 revealed variation that sorted into three corresponding distinct morphological groups in Oregon. Analyses of mtDNA and microsatellites at 15 autosomal loci from three subspecies of O. virginianus and 2 subspecies of O. hemionus (Rafinesque, 1817) revealed that each O. v. leucurus population possessed unique haplotypes, whereas O. v. ochrourus shared haplotypes with populations to the east. The most genetically differentiated whitetails were the 2 populations of O. v. leucurus (FST = 0.31), which were similarly differentiated from O. v. ochrourus (FST = 0.17–0.19); FST between O. h. hemionus and O. h. columbianus (Richarson, 1829) was 0.10. Thus, O. v. leucurus populations appear morphologically and genetically more different from each other than either is from O. v. ochrourus. Moreover, genetic differentiation among the three O. virginianus populations exceeds differentiation for existing subspecies of O. hemionus. We conclude the evidence warrants describing a new subspecies of O. virginianus in southwestern Oregon.

The complete pre-print version of this article is available here. Images below (Figure 5), display the skull, with antlers, of the Holotype of Odocoileus virginianus douglasi, white-tailed deer.