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Tectonic tremor has been explained as a swarm of low‐frequency earthquakes (LFEs), which are located on a narrow fault at the plate boundary. However, due to the lack of clear impulsive phases in the tremor signal, it is difficult to determine the depth of the tremor source with great precision. The thickness of the tremor region is also not well constrained. The tremor may be located on a narrow fault as the LFEs appear to be, or distributed over a few kilometers wide low shear‐wave velocity layer in the upper oceanic crust, which is thought to be a region with high pore‐fluid pressure. Lag times of peaks in the cross‐correlation of the horizontal and vertical components of tremor seismograms, recorded by small‐aperture arrays in the Olympic Peninsula, Washington, are interpreted to be S minus P times. Tremor depths are estimated from these S minus P times using epicenters from a previous study computed with a multibeam backprojection method. The tremor is located close to the plate boundary in a region no more than 2–3 km thick and is very close to the depths of LFEs. The tremor is distributed over a wider depth range than the LFEs. However, due to the uncertainty on the depth, it is difficult to conclude whether the source of the tremor is located at the top of the subducting oceanic crust, in the lower continental crust just above the plate boundary, or in a narrow zone at the plate boundary. Plain Language Summary: Tectonic tremor is a long, low amplitude seismic signal, with emergent onsets, and an absence of clear impulsive phases. It has been explained as a swarm of low‐frequency earthquakes (LFEs), which are located on a narrow fault at the plate boundary. It is therefore assumed that the source of the tectonic tremor is located close to the plate boundary. However, due to the lack of clear impulsive phases in the tremor signal, it is difficult to determine the depth of the tremor source and the distance of the source to the plate interface with great precision. The thickness of the tremor region is not well constrained either. The tremor may be located on a narrow fault like the LFEs, or distributed through a few kilometers wide low shear‐wave velocity layer in the upper oceanic crust, which is thought to be a region with high pore‐fluid pressure. In this paper, we show that the tremor is located close to the plate boundary in a region no more than 2–3 km thick and is very close to the depths of LFEs. Knowing the depth of the tremor source will help understand the mechanism that produces the tremor. Key Points: We use seismic data from small‐aperture arrays in the Olympic Peninsula, and tremor epicenters determined by a previous studyWe compute the depth of the tremor from S minus P times determined from stacking horizontal‐to‐vertical cross‐correlations of seismic dataTremor is located close to the plate boundary in a region no more than 2–3 km thick [ABSTRACT FROM AUTHOR]

This paper examines the public dialogues used in the wilderness designation effort on the Olympic Peninsula, Washington state, USA, to either support or negate the designation. Conflict in the concept of wilderness sprouts from incompatible philosophies of broader human-nature relationships. The concept of “wilderness” in the USA, as embedded in the 1964 Wilderness Act, reflects how the pro-designation community interprets humankind’s relationship to nature and the physical landscapes protected under the Wilderness Act are managed to reflect that community's’ understanding of nature. Conflicts arise when other communities perceive their own understandings of nature to be threatened by the concept of wilderness and the constraints it places on activities in the protected area. Using this case study of Wilderness Area designation on the Olympic Peninsula, this paper demonstrates how different sides of a conflict over wilderness legislation use cultural narratives to dominate the public dialogues surrounding wilderness. Actors in the debate seek to create a story of powerlessness and use this as a tool to legitimize their claim that nature and heritage are at risk. The case study is placed within the broader literature on political ecology and the complex role wilderness plays in American identity and heritage. [ABSTRACT FROM AUTHOR]

A small fossil sand crab carapace collected from early Eocene shallow water marine strata of the Crescent Formation exposed at Crescent Bay, Clallam County, Washington State, represents a new genus and species, Sklallamia buchanani. The carapace of S. buchanani is nearly as long as wide, is almost equally convex when viewed anteriorly, posteriorly, or laterally with smooth carapace grooves and a low median ridge, has a narrow front with anterior margins that are broadly convex on either side of the lateral margins of the ocular sinus, with broad, short ocular spines and a broad, short rostrum. This is the first confirmed fossil record of the family Albuneidae from the Pacific Basin. [ABSTRACT FROM AUTHOR]

Flowering sex ratios of dioecious plants are commonly male-biased but rarely female-biased. While greater costs of reproduction from females have been repeatedly demonstrated and explain male biases, male reproductive costs almost never exceed female costs, making the origins of female biases enigmatic. I investigated the seagrasses Phyllospadix scouleri and P. serrulatus (surfgrasses), which have some of the most extreme female-biased sex ratios documented (>90% female), to identify the mechanisms driving sex ratio bias. I developed sex-linked amplified fragment length polymorphism (AFLP) markers and applied them to three P. scouleri life stages at four sites to determine when during the life cycle sex ratio bias arises. Sex ratios were even among seedlings but became more female-biased at later life stages, indicating that sex ratios were driven by male-biased mortality. To identify when during the life cycle sex ratio bias developed, I examined sex differences in survival among seedlings and three aspects of reproductive costs that could potentially generate biased sex ratios under field conditions. No differences in seedling survival between the sexes were detected, and there was no evidence of substantial sex differences in costs of reproduction. I found no support for a trade-off between current and future reproduction or between reproductive investment and growth. Thus, costs of reproduction appear unlikely to drive sex ratio bias in surfgrass. Instead, small sex differences in growth and survival spread across the life cycle appear to be responsible for female-biased sex ratios and suggest that life history trade-offs other than reproductive costs drive sex ratio bias. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the effectiveness of smokewater as a restoration tool in germinating beargrass (Xerophyllum tenax). Beargrass is a herbaceous perennial that produces a club- or cone-shaped inflorescence of white flowers. Conservation of beargrass and restoration of its habitat on the Olympic Peninsula of Washington has been a project of the Olympic National Forest staff with the help of Skokomish and Quinault Indian Nations which reintroduced anthropogenic burning. Results of the greenhouse study revealed that higher germination rates were recorded for Quinault seeds soaked in smokewater and after undergoing stratification.

This paper documents the existence and character of a little known fire-maintained anthropogenic ecosystem in the southeastern Olympic Peninsula of Washington State, U.S.A. Due to cessation of anthropogenic burning, there is no longer an intact example of this ecosystem. We present evidence from Skokomish oral tradition, historical documents, floral composition, tree-ring analysis, stand structure, and site potential to describe former savanna structure and function. We believe this system was a mosaic of prairies, savannas, and woodlands in a forest matrix maintained through repeated burning to provide culturally important plants and animals. The overstory was dominated by Douglas-fir ( Pseudotsuga menziesii). Bear grass ( Xerophyllum tenax) likely was a dominant understory component of the savannas, woodlands, and prairie edges. These lands grew forests in the absence of anthropogenic burning. Wide spacing of older trees or stumps in former stands and rapid invasion by younger trees in the late 1800s and early 1900s suggest a sudden change in stand structure. Shade-intolerant prairie species are still present where openings have been maintained but not in surrounding forests. Bark charcoal, fire scars, tree establishment patterns, and oral traditions point to use of fire to maintain this system. A common successional trajectory for all these lands leads to forested vegetation. These findings suggest that frequent application of prescribed burning would be necessary to restore this ecosystem. [ABSTRACT FROM AUTHOR]

We assessed the effect of campgrounds on American crow (Corvus brachyrhynchos) populations on the Olympic Peninsula in Washington, USA, because crows are potential nest predators for marbled murrelets (Brachyramphus marmoratus). We measured resource use, home range, relative abundance, and reproduction for 39 crows in 13 campgrounds that varied in size and proximity to other sources of anthropogenic food. Campgrounds concentrated crow populations and individual resource use. However, campgrounds did not provide optimal conditions for reproduction. Instead, reproduction was highest for crows that accessed exurban areas surrounding campgrounds. Concentration of use in exurban lands by 6 crows that nested >5 km from camprounds or human settlements confirmed the far-reaching effects of human activity in this area on crows. We concluded that human settlements fueled crow population growth on the Olympic Peninsula, and remote campgrounds absorbed this growth through colonization. As exurban crow populations expand, campgrounds likely will experience increases in local abundance of crows. Our observations do not suggest that rising crow populations will reduce the nesting success of other birds near campgrounds, but crows may indicate the suitability of campgrounds to other human commensals. Managing food resources within campgrounds may be insufficient to curtail crow population growth. Instead, regional cooperation is needed to identify and reduce food sources at broad spatial scales to target source populations. [ABSTRACT FROM AUTHOR]

The article presents a study on the habitat availability and landscape change in the southern Appalachian Highlands and Olympic Peninsula in the U.S. It mentions that species habitats in Olympic Peninsula are affected by variation in the rates of land cover change for public lands. It highlights that effective conservation can be ensured by both landscape-level approaches and species level approaches related to biodiversity and ecosystem processes.