Date of this Version
Oregon State University, Agricultural Experiment Station, Special Report 1096, September 2009
Dry forests throughout the United States are fire-dependent ecosystems, and much attention has been given to restoring their ecological function. As such, land managers often are tasked with reintroducing fire via prescribed fire, wildland fire use, and fire-surrogate treatments such as thinning and mastication. During planning, managers frequently are expected to anticipate effects of management actions on wildlife species. This document represents a synthesis of existing knowledge on wildlife responses to fire and fire-surrogate treatments, presented in a useful, management-relevant format. Based on scoping meetings and dialogue with public lands managers from throughout the United States, we provide detailed, species-level, summary tables for project biologists and fire managers trying to anticipate the effects of fire and fire-surrogate treatments on local wildlife species. We performed an extensive survey of the published, peer-reviewed scientific literature on wildlife response to fire and fire-surrogate treatments. In total, we reviewed more than 150 articles, included 90 articles in our database, resulting in 4,937 records of 313 vertebrate species. We grouped the dry forests of the continental United States into six regions: pine east, pine west, interior mixed-conifer, Pacific mixed-conifer, eastern hardwood, and Great Lakes. Further, studies were categorized on the basis of the following: • Fire severity (in which low = 0–60% canopy mortality and high = more than 60% canopy mortality), and • Time since fire (expressed in ranges of 0–4 years, 5–9 years, and 10 years or more) Detailed tables summarizing published studies and individual species responses from each of the regions are in the appendixes. These are intended as “look up” tables for land managers engaged in planning. We found numerous peer-reviewed studies that provided examples of fire-adapted and fire-dependent wildlife species throughout dry forest types (Bachman’s sparrow, black-backed woodpecker, gopher tortoise, etc.). These studies clearly showed that many species consistently respond positively to fire, supporting the assumption that these species have evolved with and are dependent on fire (of varying severities and extents) as a regular ecological process. However, not all species respond positively, and some species have no detectable response to the conditions created by fire or fire surrogates. Published literature was most available for birds and small mammals and least abundant for herpetofauna and large mammals (ungulates, carnivores). Moreover, often there were sampling issues associated with the wildlife literature, reducing the strength of inference in many cases. Regional coverage of studies was best for short-term effects of surface fires in eastern pine systems and high-severity fires in the interior mixed-conifer forests of the western United States. Major gaps in knowledge exist in the current scientific literature. Much ground has been gained by the Fire and Fire Surrogate system of experiments with respect to stand-level knowledge of surface fire and fire surrogates. However, tremendous gaps persist with respect to mixed-severity fire, longer term response to mixed- and highseverity fire, and the effects of repeated fire (all severities) on wildlife.