Barbara C. Wales

Status and trends of habitats of terrestrial vertebrates in relation to land management in the interior Columbia river basin

Abstract We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conservation concern within the interior Columbia river basin study area. The three alternatives were proposed in a Supplemental Draft Environmental Impact Statement (SDEIS) that was developed for lands in the study area administered by the US Department of Agriculture (USDA) Forest Service (FS) and US Department of Interior (USDA) Bureau of Land Management (BLM). To evaluate effects of these alternatives, we developed Bayesian belief network (BBN) models, which allowed empirical and hypothesized relations to be combined in probability-based projections of conditions. We used the BBN models to project abundance and distribution of habitat to support potential populations (population outcomes) for each species across the entire study area. Population outcomes were defined in five classes, referred to as outcomes A–E. Under outcome A, populations are abundant and well distributed, with little or no likelihood of extirpation. By contrast, populations under outcome E are scarce and patchy, with a high likelihood of local or regional extirpation. Outcomes B–D represent gradients of conditions between the extremes of classes A and E. Most species (65%, or 20 of 31) were associated with outcome A historically and with outcomes D or E currently (55%, or 17 of 31). Population outcomes projected 100 years into the future were similar for all three alternatives but substantially different from historical and current outcomes. For species dependent on old-forest conditions, population outcomes typically improved one outcome class — usually from E or D to D or C — from current to the future under the alternatives. By contrast, population outcomes for rangeland species generally did not improve under the alternatives, with most species remaining in outcomes C, D, or E. Our results suggest that all three management alternatives will substantially improve conditions for most forest-associated species but provide few improvements for rangeland-associated vertebrates. Continued displacement of native vegetation by exotic plants, as facilitated by a variety of human-associated disturbances, will be an on-going challenge to the improvement of future conditions for rangeland species.

Evaluation of Landscape Models for Wolverines in the Interior Northwest, United States of America

Abstract The wolverine (Gulo gulo) is an uncommon, wide-ranging carnivore of conservation concern. We evaluated performance of landscape models for wolverines within their historical range at 2 scales in the interior Northwest based on recent observations (n = 421) from Washington, Oregon, Idaho, and Montana. At the subbasin scale, simple overlays of habitat and road-density classes were effective in predicting observations of wolverines. At the watershed scale, we used a Bayesian belief network model to provide spatially explicit estimates of relative habitat capability. The model has 3 inputs: amount of habitat, human population density, and road density. At both scales, the best models revealed strong correspondence between means of predicted counts of wolverines and means of observed counts (P < 0.001). Our results can be used to guide regional conservation planning for this elusive animal.

Wildlife and Invertebrate Response to Fuel Reduction Treatments in Dry Coniferous Forests of the Western United States: A Synthesis

This paper synthesizes available information on the effects of hazardous fuel reduction treatments on terrestrial wildlife and invertebrates in dry coniferous forest types in the West. We focused on thinning and/or prescribed fire studies in ponderosa pine (Pinus ponderosa) and dry-type Douglas-fir (Pseudotsuga menziesii ), lodgepole pine (Pinus contorta), and mixed coniferous forests. Overall, there are tremendous gaps in information needed to evaluate the effects of fuel reduction on the majority of species found in our focal area. Differences among studies in location, fuel treatment type and size, and pre- and post-treatment habitat conditions resulted in variability in species responses. In other words, a species may respond positively to fuel reduction in one situation and negatively in another. Despite these issues, a few patterns did emerge from this synthesis. In general, fire-dependent species, species preferring open habitats, and species that are associated with early successional vegetation or that consume seeds and fruit appear to benefit from fuel reduction activities. In contrast, species that prefer closed-canopy forests or dense understory, and species that are closely associated with those habitat elements that may be removed or consumed by fuel reductions, will likely be negatively affected by fuel reductions. Some habitat loss may persist for only a few months or a few years, such as understory vegetation and litter that recover quickly. The loss of large-diameter snags and down wood, which are important habitat elements for many wildlife and invertebrate species, may take decades to recover and thus represent some of the most important habitat elements to conserve during fuel reduction treatments. Management activities that consider the retention of habitat structures (such as snags, down wood, and refugia of untreated stands) may increase habitat heterogeneity and may benefit the greatest number of species in the long run.

Maintaining Populations of Terrestrial Wildlife Through Land Management Planning: A Case Study

ABSTRACT Regulations and directives associated with enabling legislation for management of national forests in the United States require maintenance of viable populations of native and desired non-native wildlife species. Broad-scale assessments that address ecosystem diversity cover assessment of viability for most species. We developed an 8-step process to address those species for which management for ecosystem diversity may be inadequate for providing ecological conditions capable of sustaining viable populations. The process includes identification of species of conservation concern, description of source habitats, and other important ecological factors, grouping species, selection of focal species, development of focal species assessment models, development of conservation strategies, and designing monitoring, and adaptive management plans. Following application of our screening criteria, we identified 209 of 700 species as species of conservation concern on National Forest System lands east of the crest of the Cascade Mountains in Oregon and Washington State, USA. We aggregated the 209 species of conservation concern into 10 families and 28 groups based primarily on habitat associations (these are not phylogenetic families). We selected 36 primary focal species (78% birds, 17% mammals, 5% amphibians) for application in northeast Washington State, USA based on risk factors and ecological characteristics. Our assessment documented reductions in habitat capability across northeast Washington State compared to historical conditions. To address such changes, for each focal species we developed conservation strategies that included habitat protection and restoration and amelioration of threats. We combined conservation strategies for individual species with other focal species and with management proposals for other resources (e.g., recreation, fire, and fuels management) to develop a multi-species, multi-resource management strategy. The information generated from our approach can be directly translated into land management planning through development of desired conditions, objectives, and standards and guidelines to improve the probability that desired population outcomes will be achieved. However, it should be noted by practitioners that a practical conservation planning process, such as ours, cannot remove all uncertainty and risk to species viability.