As human demand for ecosystem products increases, management intervention may become more frequent after environmental disturbances. Evaluations of ecological responses to cumulative effects of management interventions and natural disturbances provide critical decision-support tools for managers who strive to balance environmental conservation and economic development. We conducted an experiment to evaluate the effects of salvage logging on avian community composition in lodgepole pine (Pinus contorta) forests affected by beetle outbreaks in Oregon, USA, 1996–1998. Treatments consisted of the removal of lodgepole pine snags only, and live trees were not harvested. We used a Bayesian hierarchical model to quantify occupancy dynamics for 27 breeding species, while accounting for variation in the detection process. We examined how magnitude and precision of treatment effects varied when incorporating prior information from a separate intervention study that occurred in a similar ecological system. Regardless of which prior we evaluated, we found no evidence that the harvest treatment had a negative impact on species richness, with an estimated average of 0.2–2.2 more species in harvested stands than unharvested stands. Estimated average similarity between control and treatment stands ranged from 0.82–0.87 (1 indicating complete similarity between a pair of stands) and suggested that treatment stands did not contain novel assemblies of species responding to the harvesting prescription. Estimated treatment effects were positive for twenty-four (90%) of the species, although the credible intervals contained 0 in all cases. These results suggest that, unlike most post-fire salvage logging prescriptions, selective harvesting after beetle outbreaks may meet multiple management objectives, including the maintenance of avian community richness comparable to what is found in unharvested stands. Our results provide managers with prescription alternatives to respond to severe beetle outbreaks that continue to occur across extensive portions of the dry forests of western North America.
Intensively-managed forest (IMF) ecosystems support environmental processes, retain biodiversity and reduce pressure to extract wood products from other forests, but may affect species, such as plethodontid salamanders, that are associated with closed canopies and possess limited vagility. We describe: (1) critical aspects of IMF ecosystems; (2) effectiveness of plethodontid salamanders as barometers of forest change; (3) two case studies of relationships between salamanders and coarse woody debris (CWD); and (4) research needs for effective management of salamanders in IMF ecosystems. Although plethodontid salamanders are sensitive to microclimate changes, their role as ecological indicators rarely have been evaluated quantitatively. Our case studies of CWD and salamanders in western and eastern forests demonstrated effects of species, region and spatial scale on the existence and strength of relationships between plethodontid species and a “critical” microhabitat variable. Oregon slender salamanders (Batrachoseps wrighti) were more strongly associated with abundance of CWD in managed second growth forests than ensatina salamanders (Ensatina eschscholtzii). Similarly, CWD was not an important predictor of abundance of Appalachian salamanders in managed hardwood forest. Gaining knowledge of salamanders in IMF ecosystems is critical to reconciling ecological and economic objectives of intensive forest management, but faces challenges in design and implementation.
The value of non‐commodity ecosystem services provided by forests is widely recognized, but intensive forest management practices are increasing, with uncertain consequences for a multitude of these services. Quantitative relationships among biodiversity conservation, timber production and other ecosystem services remain poorly understood, especially during the early‐successional period of intensively managed forestlands. We manipulated management intensity in regenerating forest plantations to test the prediction that treatments aimed at maximizing timber production decrease biodiversity conservation and non‐timber services. We measured species richness of 3 taxonomic groups and 13 proxies for provisioning, cultural and regulating services within stands randomly assigned to one of the three herbicide application intensities or an untreated control. Herbicides increased allocation of net primary production to crop trees, increasing projected timber volume and revenues at 40‐ and 60‐year harvest ages. Commonly used herbicide prescriptions reduced culturally valued plants by 71%, wild‐ungulate forage by 41%, avian richness by 20% and pollinator floral resources by 42%, the latter being associated with 38% fewer pollinator species. However, agriculturally valued bumblebees, pollination of blueberries, avian‐mediated arthropod control, wild ungulate observations and regulation services tied to forest productivity appeared unaffected by increasing management intensity and timber production. Species richness and flora‐provided services in young forest plantations exhibited strong trade‐offs with projected timber production, whereas post‐treatment vegetation regeneration and site‐level variation likely maintained a range of other services. Although vegetation recovery is important for supporting wildlife and some ecosystem services on industrial forestlands, it is unlikely that any single prescription can optimize both timber and non‐timber benefits to society across managed forest landscapes. Instead, producing different services in discrete portions of the landscape may be necessary. Synthesis and applications. We tested the effects of intensive forest management via herbicides on ecosystem services and found that biodiversity responses and services from early‐successional vegetation trade‐off against timber production. A number of services appeared to be compatible with timber production, although no single prescription optimized the full range of services. Stand‐level biodiversity conservation and a variety of services could potentially be provided by treatment skips and less‐intensive management on productive sites, although it is unlikely that all services can be optimized without landscape‐level planning.