Treesearch

The Pacific marten once ranged throughout coastal forests of the Pacific Northwest, but by the late 1940s, it was thought to be extinct. In 1996, however, a population was found in northern California. This member of the mustelid family, which includes weasels and fishers, depends on diverse, mixed-conifer forests with a dense understory of salal and other shrubs. Habitat loss, forest fragmentation, disease, trapping, and fatality from collisions with motor vehicles have contributed to the decline of the Humboldt marten, a subspecies found in limited areas of coastal Oregon.Conservation...

The federally threatened northern spotted owl (Strix occidentalis caurina) has been intensively studied across its range, and habitat needs for the species have influenced forest management in northwestern North America for decades. Dense forest canopies are often reported in the scientific literature and agency management plans as an important habitat attribute for spotted owls, though the means of measuring forest canopy and interpreting species requirements vary across studies and more importantly, among management plans. We used light detection and ranging (lidar) measurements of...

The success or failure of fish populations in rivers is intimately linked to a complex and interconnected series of ecological interactions. This complexity can make it difficult to predict how organisms within river ecosystems will respond to management actions and other environmental changes. To aid in solving this dilemma, we constructed a food web simulation model termed the Aquatic Trophic Productivity (ATP) model. The ATP model mechanistically links the success of fish populations to the dynamics of river food webs and the abiotic conditions that influence these webs. This report...

As central components of food webs worldwide, amphibians provide vital ecosystem services. The continental United States alone has 230 amphibian species and is the world hotspot for salamander species. However, this amphibian biodiversity is threatened by Batrachochytrium salamandrivorans (Bsal), a fungal pathogen native to Asia that spread to Europe and is killing fire salamanders in the wild. Laboratory testing has shown several North American species are also vulnerable to Bsal infection. The spread of Bsal is a chief concern, and at this time, it is highly probable Bsal will appear in...

In ponderosa pine forests of western North America, wildfires are becoming more frequent and affecting larger areas, while prescribed fire is increasingly used to reduce fuels and mitigate potential wildfire severity. Both fire types leave trees that initially survive their burn injuries, but will eventually die. Predicting delayed tree mortality has received considerable research attention to aid in post-fire planning and management. The amount of crown scorched is recognized as the most useful variable for discriminating between trees that live or die, but models gain discrimination with...

This is a Commentary for the 50th Anniversary Issue of Herpetological Review on the Diseases section of the journal which I initiated in December 2007. This section aimed to accelerate the pace and communication of science findings relative to herpetological emerging infectious diseases. Since the section was launched in late 2007, 185 disease articles by 594 authors have been published, including reports on seven disease-causing agents and a geographic scope spanning 42 countries and 35 US states. A world community has engaged in this work, empowering land managers, local biologists, the...

We examined the relationship between urban trees and the sales price of single-family homes in Tampa, Florida. We chose Tampa, because the city is facing major redevelopment pressure that may impact the association between trees and house price. In particular, a frequently voiced view in Tampa’s development community is that trees adversely affect the value of houses that are being sold for redevelopment. We estimated hedonic models of sales price controlling for house and neighborhood characteristics and correcting for spatial autocorrelation (n = 1,924). We found that trees within 152m...

Forests provide significant long-term carbon (C) storage, but have the potential to increase future C emissions with a changing climate. Aboveground biomass, C stores, and the effect of disturbance were examined using forest inventory data collected across all ownerships on 6.2 million ha in Coastal Alaska. We modelled six C pools using empirical data, estimated two others using the literature, and quantified estimate uncertainty. The average (±SE) aboveground live (218.9 ± 4.6 Mg/ha) and log (28.1 ± 1.8 Mg/ha) biomass in the Alaskan Temperate ecoregion were among the lowest in the Pacific...

A riverscape perspective considers the ecological and social landscape of the river and its valley. In this context, we examined the spatial arrangement of protective policies for river networks. Riparian land-management standards are policy efforts that explicitly restrict certain management actions, e.g., timber harvest or land clearing, in stream-adjacent lands in order to protect water quality and aquatic habitat. In western Oregon, USA, management standards for riparian lands vary across federal, state, and private landownerships and land uses, projecting a patchwork of protective...

The marbled murrelet (Brachyramphus marmoratus) is a threatened coastal bird that feeds on fish and nests in old-growth forests. In northwest Washington, murrelet populations are declining despite protections provided by the Northwest Forest Plan. Wildlife biologists Martin Raphael and Tom Bloxton, with the USDA Forest Service Pacific Northwest Research Station, used radio telemetry—the first study of its kind in Washington—to develop a detailed picture of the challenges faced by marbled murrelets. Teresa Lorenz analyzed the resulting data to gain further insights into the ecology of these...