Wildfire and Spotted Owls: It’s a Burning Issue

Symposium
ROOM: Room 240 – La Cienega
SESSION NUMBER: 34
 
Study results suggest that wildfires in the western U.S. have increased in size and severity over the past several decades. This increase has raised concern over the effects of fire, particularly high-severity fire, on threatened and endangered species, including the spotted owl (Strix occidentalis). These owls typically nest within late-seral forests that have high-canopy cover, ladder fuels, and are vulnerable to high-severity, stand-replacing fire. Consequently, forest managers have developed and implemented restoration and fuels-reduction prescriptions to reduce fire risk. Controversy has arisen because of uncertainty regarding the tradeoffs between the risk to owls from habitat loss because of forest restoration activities versus the effects of wildfire. Thus, integrating protection of nesting habitat for spotted owls with forest restoration and fuels-reduction activities presents a challenge to managers. Studies are inconsistent on the effects of high-severity wildfire on spotted owls, with some suggesting that high-severity wildfire may be a serious problem for spotted owls and others suggesting that high-severity fire is not an immediate problem and can be beneficial. Confounding the issue is the interaction of effects of fire and those of salvage logging following wildfire. This symposium will provide an opportunity for presentation of current information on salvage logging effects, trends in wildfire extent and severity within the forest types occupied by spotted owls, as well as results of studies on effects of prescribed and wildfire on spotted owls. Gathering this information in one place at one time will advance our understanding on effects of fire on spotted owls and their habitat and hopefully ameliorate this conservation conflict.

10:30AM The Effects of Wildfire on Spotted Owls: The Elements of an Emerging Conservation Conflict
  Ralph J. Gutierrez; Gavin M. Jones; M. Zachariah Peery
The effects of wildfire on spotted owls (Strix occidentalis) have long been of interest to wildlife biologists, forest and fire managers, and special interests groups. Conservation planners initially (~1980-2005), deemed these effects to be insignificant to owls because owls evolved in fire-adapted landscapes. However, it was also recognized that large high-severity fires could be detrimental to local populations because of fire effects and additional impacts of salvage logging. Early studies supported this view that low- and moderate-severity fires were relatively benign to owls, but salvage logging could increase the impacts. In the last decade, fire frequency studies have demonstrated an increase in high-severity fires in the range of the spotted owl. Moreover, climate change has been predicted to increase the possibility of more large fires in the future. With the occurrence of several large megafires in California, Oregon, and Arizona, the focus of research has shifted from the effects of low to moderate severity fires on owls to the response of owls to high-severity fires. Two general, but contrasting, hypotheses have emerged from these studies – 1) high-severity fire is benign to spotted owls and 2) high-severity fire can have major impacts to local spotted owl populations. Thus, the stage has been set for conservation conflict among stakeholders and scientists over two broad issues: 1) the veracity of the science and 2) the appropriate management of forests to reduce the risk of high-severity fire, including salvage logging (i.e., do impacts to owls from fire-reduction management and salvage logging outweigh the risks of wildfire, especially high-severity fire?). We here discuss the roots and structure of this emerging conservation conflict, assess the results of recent published studies in the context of framing the conservation conflict, and offer some suggestions for interpreting study results and structuring future studies as ways to reduce conflict.
10:50AM Federal Wildland Fire Policy & Management
  Bryan Rice
The Federal Wildland Fire Management Policy and Program Review (1995) clarifies policies on the role of fire, balancing risk, and the management of risk, including the risk of no action. The National Cohesive Wildland Fire Management Strategy (2014) articulates three collaborative goals: resilient landscapes, fire adapted communities, and safe and effective wildfire response. Management of wildland fire in spotted owl habitat relies on each of these three national goals, as they are implemented at a regional and local level. Resilient landscapes ultimately provide longer term stability to spotted owl habitat from extreme risks of disturbance from wildfire, insects, disease and climate extremes. Fire adapted communities provide social tolerance, as well as a buffer to and from wildlands and human populations and infrastructure. A safe and effective wildfire response is necessary to reduce risks from unwanted wildfire, but also to help maintain vegetation that can serve as transitory habitat until forests stands mature and landscape resilience is achieved. Wildland fire policies are informed or validated by the Quadrennial Fire Review (2014), which examines wildland fire trends and factors that shape trends and influence solutions. Policies are also shaped by ongoing Joint Fire Science Program research projects and local consortia that coordinate research and help inform management solutions to key scientific issues. Finally, policy is also guided or directed by the regulation environment – both for spotted owl management -as well as environmental factors, e.g., air quality regulation and management.
11:10AM Management of Spotted Owls and Their Habitat in the Western United States
  Shaula Hedwall
Northern (Strix occidentalis caurina) and Mexican spotted owls (S. o. lucida) are listed as Threatened under the Endangered Species Act (Act); the California spotted owl (S. o. occidentalis) is listed as species of Special Concern by state of California and the U.S. Fish and Wildlife Service is currently conducting a species status assessment to determine if the subspecies should be listed as threatened or endangered under the Act. The common threat to all three subspecies is the historic loss of habitat and projected trends in habitat loss due to historic, and in some cases, current forest management practices. Over approximately the last two decades an emerging threat is the effect of large, high-severity, stand-replacing fire and concerns regarding management of these areas post-fire. The debate surrounding the conservation and management of these subspecies and their habitat is vigorous, and often contentious. The northern and Mexican spotted owls have recovery plans that recommend protecting existing populations, managing for habitat into the future, managing threats, and monitoring populations and habitat. These plans, as well as management recommendations for the California subspecies, encourage active forest management to aid in development of large trees, and restoration of natural processes, such as fire, to aid in the development of more resilient forests. However, implementation of treatments designed to promote spotted owl habitat is limited and the monitoring needed post-treatment to inform future management is sparse. We will discuss the current status of implementation of these management recommendations and the how monitoring is informing current and future forest management for each subspecies.
11:30AM Native American Perspectives on Fire Effects on Spotted Owls
  Dee Randall; Serra Jeanette Hoagland
Fire is an important natural disturbance process in forested ecosystems and has immense cultural values for Indian people throughout the southwest. Fire can also be used as a valuable tool to restore forest structure and conditions that are more indicative of pre-settlement conditions. The San Carlos Apache Indian Reservation is located in eastern Arizona and is home to the San Carlos Apache people, a federally recognized tribe. The reservation comprises 1.8 million acres. A key strategic goal of the Tribe is to restore the ecosystem to pre-European settlement conditions. Apaches have “lived with fire” and “benefited from fire” for a long time. Since wildfires played an important role in maintaining pre-settlement conditions, re-introducing fire to its historic frequency, severity, and extent is a major focus for the Forestry and Fire Management Programs. The San Carlos Apache reservation is home to serval different animal and plant species, the Mexican Spotted owl being one. Although the owl is consider a messenger or bad omen, elders believe there is a place and purpose for all living things. Implementing traditional values through forest management activities can reap numerous benefits and tribes are playing an active role in returning fire to the land, while also balancing multiple objectives. Bringing tribes to the table, as either collaborators or partners in research and active forest management is an important step in achieving landscape scale forest restoration.
11:50AM Using Fire as a Management Tool in Southwestern Forests
  Tessa Nicolet
Current ecosystem condition, potential fire behavior, values at risk, and desired outcomes are key in determining how to manage a fire. The inevitability of fire in our southwestern ecosystems demands our attention in managing these landscapes at a large spatial scale. The scale of the needs for restoration begs the use of fire as a primary tool. How this tool is used in varying ecosystem types, including habitat for threatened and endangered species is a management challenge that requires careful and purposeful engagement of all specialist. The course of action built on these considerations can be very complex and require many fire management and other specialty resources. Land management agencies need to communicate the intent and desired outcomes from any fire not only to the public but to internal audiences. The idea of “allowing fire to move about naturally” is very site specific and may not be appropriate in many cases. Most fires may require very engaged fire management in order to meet objectives and desired outcomes, especially in Mexican Spotted owl habitats. Many decision support tools can be very important in shaping courses of actions and important dialogues among stakeholders and partners. Using some southwestern fires as examples, we will highlight some tools that can be helpful for future fire management and as communication tools when using fire as a management tool in southwestern forests.
1:10PM Beyond ‘Megafires’: the Role of Fire Complexity and Spatial Patterns of Severe Fire on Spotted Owls
  Gavin Jones; R. J. Gutiérrez; Nicole F. Pietrunti; M. Z. Peery
In September and October 2014 the King Fire burned nearly 100,000 acres of forest in California’s Sierra Nevada, of which 50,000 acres burned at high severity (75-100% canopy mortality). This ‘megafire’ burned through portions of a long-term spotted owl (Strix occidentalis) demographic study area, providing a near-perfect before-after control-impact natural experiment of the effects of high-severity wildfire on this species. While we found a strong negative effect of severe fire on territory occupancy and avoidance of severely burned forest during foraging bouts, other researchers have reported either neutral or positive effects of fire, even severe fire, on spotted owls. This raises the question, “why have different studies revealed conflicting results about severe fire effects on owls?” We hypothesize that the effect of severe fire on spotted owls is highly contextual, depending in part on severe fire patch size, configuration, and complexity (e.g., pyrodiversity, patch mosaics, edge-to-area ratios). We explore this hypothesis using the King Fire as a case study. We also compare spatial characteristics of fires from other studies and the conclusions that were reached by other researchers with respect to the effect of fire on owls. Our goal is to not provide an explanation about the question of whether severe fire is “good” or “bad”; instead, we argue that the answer could be “both.” We suggest future studies of the effects of severe fire on spotted owls should consider, as we do here, the landscape ecology of fire.
1:30PM California Spotted Owl Habitat Use Patterns in a Burned Landscape
  Stephanie A. Eyes; Susan L. Roberts; Matthew D. Johnson
Fire is a dynamic ecosystem process of mixed-conifer forests of the Sierra Nevada, but there is limited scientific information addressing wildlife habitat use in burned landscapes. Recent studies have presented contradictory information regarding the effects of stand-replacing wildfires on Spotted Owls and their habitat. While fire promotes heterogeneous forest landscapes shown to be favored by owls, high severity fire may create large canopy gaps that can fragment the closed-canopy habitat preferred by Spotted Owls. We used radio-telemetry to determine whether foraging California Spotted Owls in Yosemite National Park, California, USA, showed selection for particular fire severity patch types within their home ranges. Our results suggested that Spotted Owls exhibited strong habitat selection within their home ranges for locations near the roost and edge habitats, and weak selection for lower fire severity patch types. Although owls selected high contrast edges with greater relative probabilities than low contrast edges, we did not detect a statistical difference between these probabilities. Protecting forests from stand-replacing fires via mechanical thinning or prescribed fire is a priority for management agencies, and our results suggest that fires of low to moderate severity can create habitat conditions within California Spotted Owls’ home ranges that are favored for foraging.
1:50PM California Spotted Owl-Wildfire Associations at Territory, Landscape and Bioregional Scales in the Sierra Nevada, California
  John J. Keane; Rahel Sollmann; Ross A. Gerrard; Claire V. Gallagher; Paula A. Shaklee; Thomas E. Munton; James Baldwin
Increasing recent trends in amounts of wildfire, and more specifically in the proportion and increased patch sizes of area that burns at high severity, have heightened interest in the effects of fire on California spotted owls across the Sierra Nevada (Strix occidentalis occidentalis). Our research has addressed owl-fire associations at territory, landscape and bioregional spatial scales. At the territory and landscape scales we investigated the response of owls to wildfire and salvage logging across multiple fires that occurred in the vicinity of long-term owl demographic monitoring study areas. Fires ranged in terms of the proportion of high-severity from ~10%-50%. At the owl territory-scale, occupancy was positively associated with the sum amount of suitable habitat that was either unburned or burned at low and moderate severities. Breeding probability was positively associated with the pre-fire amount of suitable habitat and negatively associated with the amount suitable habitat burned across all severities. Both occupancy and breeding probability were negatively associated with post-fire salvage logging. At the landscape scale, the number and spacing of owl territories remained near pre-fire levels across fires that burned at primarily low-moderate severities. At the bioregional scale we used an empirically-based habitat suitability model to map habitat and assess changes in suitability between 1990-2012. The largest observed declines in predicted habitat suitability were associated with areas that had experienced wildfire. Aligning the distribution of dense, older forest conditions to areas characterized by biophysical factors, such as topographic position or moisture availability/stress, hypothesized to have a higher probability to support such forest structure into the future has been proposed as a possible management option to increase forest resilience to stressors. Using habitat suitability models and spatial optimization approaches we explored the distribution of high suitability habitat under different management objectives to align habitat with the various underlying biophysical factors.
2:10PM Reconciling Forestchange and Contemporary Fire Patterns with Owl Habitat Requirements Inhistorically Frequent-Fire Forests
  Brandon Collins
Many western North American forest types have experienced considerable changes in ecosystem structure, composition, and function as a result of both fire exclusion and timber harvesting. A principal challenge of management in these forest types has been addressing these significant ecosystem changes while maintaining and improving habitat for sensitive species. Contemporary re-measurements of a systematic historical forest inventory were used to investigate forest change in the central Sierra Nevada. The historical data opportunistically spanned a significant land management agency boundary, which protected part of the inventory area from timber harvesting. This allowed for a robust comparison of forest change between logged and unlogged areas. Additionally, the effects of recent management activities aimed at forest restoration were compared to the same areas historically. Live basal area and tree density significantly increased from historical to present in both logged and unlogged areas. Both shrub cover and the proportion of live basal area occupied by pine species declined from historical to present in both areas, but statistical significance was inconsistent. The most notable difference between logged and unlogged areas was in the density of large trees, which declined significantly in logged areas, but slightly increased (non-significant) in unlogged areas. In general, areas with no recent forest restoration activities experienced the greatest change from 1911 to present. The magnitude and overall extent of forest change throughout the Sierra Nevada is undoubtedly linked with both the uncharacteristic fire patterns and the recent tree mortality observed throughout the Sierra Nevada. Given these observed threats to forests and a future of climate change, management for other values in forests will be, in the long run, futile without also managing for long-term forest resilience.
2:30PM Are Mixed-Severity Fires a Threat to California Spotted Owls?
  Dominick A. DellaSala; Monica Bond; Derek Lee; Chad Hanson
At the territory scale, mixed-severity fires in the Sierra Nevada provide landscape heterogeneity (pyrodiversity) associated with California spotted owl (Strix occidentalis occidentalis) nesting (unburned-moderate) and foraging (high severity) habitat as well as habitat for numerous fire-adapted species. Amount of high-severity fire in the Rim Fire, Stanislaus National Forest, within an owl pair’s 120-ha Protected Activity Center had no effect on occupancy, although occupancy by single owls declined slightly as the extent of severe fire patches increased. Fire of all severities had no effect on occupancy by spotted owls in Yosemite National Park. Long-term studies in southern California found that while site occupancy probability declined with increasing amounts of high-severity fire in the 203-ha core area, this effect was evident only in marginal sites with a history of low occupancy and reproduction. In consistently reproductive sites the amount of high-severity fire had negligible effects on occupancy and reproduction. Radio-marked spotted owls foraged preferentially in high-severity patches with mature forest structure (snags) in the southern Sierra Nevada and used high- and moderate-severity patches in the San Bernardino Mountains in proportion to availability. Structural complexity (especially high density of snags and shrubs) is important as spotted owl foraging habitat. I discuss why managers wishing to maintain this increasingly rare habitat can manage for pyrodiversity generated by mixed-severity fires under the 2012 forest planning rule and, in doing so, could also prohibit post-fire logging within 2.4 km of nest and roost sites, which corresponds to interim spotted owl management guidelines of the Forest Service’s Pacific Southwest Research Station. I also discuss whether high-severity patches are increasing with respect to appropriate baselines.
2:50PM Refreshment Break
3:20PM Northern Spotted Owls and Wildfire in the Klamath Province of Northern California: Linkages between Fire Regimes and Habitat Quality
  Alan B. Franklin; Jeremy T. Rockweit; Peter C. Carlson
Historically, the Klamath physiographic province in northern California had a dynamic fire regime that was a major disturbance process in Douglas‑fir (Pseudotsuga menziesii)/hardwood forest types. The Douglas‑fir/hardwood forest type is a fire adapted plant community in northwestern California, with the development of late‑successional stands influenced by frequent, low to moderate severity fires with smaller patches of high severity fire creating a landscape patchwork of intermixed early seral stands (Skinner 1995). Northern spotted owl habitat quality in the Klamath physiographic province of northwestern California appears to increase when both interior older forest and edge between older forest and early seral stages occur within an owl’s territory. While increased interior older forest promotes higher adult survival, edge promotes high reproduction. The trade-off of interior older forest and edge differentially affecting survival and reproduction may be the result of the evolution of northern spotted owls in a fire-dominated landscape. The natural wildfire regime of the Klamath province may be an important driving force behind the observed pattern of heterogeneity in vegetation types and seral stages that constitute high quality northern spotted owl habitat. The response of northern spotted owl populations in this region to different fire severities was recently examined using a retrospective BACI design. Mixed-severity fires that burned at predominantly low-severity had little effect on spotted owl survival and recruitment while fires characterized by more medium to high burn severities negatively affected spotted owl survival, with varying effects on recruitment. Reduced survival and increased recruitment rates on some territories affected by medium to high severity fires suggested that post-fire habitat quality was reduced resulting in territories that were marginally capable of supporting owls. Thus, multiple lines of evidence exist linking disturbance from a dynamic fire regime with habitat quality for northern spotted owls in northern California.
3:40PM Interactions between Mixed Severity Wildfire and Forest Types Used by Northern Spotted Owls
  Damon B. Lesmeister; David M. Bell; Raymond J. Davis; Matthew J. Gregory; Jody C. Vogeler
Mixed-severity fires are among the most widespread and complex disturbances influencing western North American forests, and are the least understood with regard to impacts on wildlife and their habitats. In 2013, three concurrent mixed severity wildfires of approximately the same size (~10,000 ha each), known as the Douglas Complex, burned under moderate fire-weather conditions in southwestern Oregon. Two of the fires burned within a long-term northern spotted owl demographic study area. Within the fire perimeter light detection and ranging (LiDAR) data were acquired in 2012 (pre-fire) and again two months post-fire. Our objectives were to quantify the immediate impact of fire severity classes (low, moderate, high) on forest types used by northern spotted owls for nesting and roosting, and quantify the interaction between fire severity and pre-fire vegetation condition. We used northern spotted owl nesting and roosting locations, and pre-fire LiDAR-based variables (vegetation height, vegetation cover, density of large trees, and stand complexity) to develop a model that indicated the strong selection for old forest types with a high degree of complexity. We projected the pre-fire model algorithm to post-fire conditions and quantified the change in suitability for nesting and roosting. Suitability decreased by 74% (high), 25% (moderate), and 1% (low) depending on fire severity. We calculated odds ratios based on the probability that pre-fire suitable and unsuitable forest types would burn at each fire severity class. Unsuitable forest types were more likely to burn at moderate (1.14 ± 0.02) or high (1.13 ± 0.04) rather than low (0.89 ± 0.02) severity. Conversely, suitable forest types burned at low (1.31 ± 0.07) rather than moderate (0.61 ± 0.04) or high (0.64 ± 0.10) severity. Our study suggests that compared to younger forests, structurally complex and old forests are more resistant to stand-replacing wildfires under moderate fire-weather conditions.
4:00PM Higher Fire Severity Drives Reduced Mexican Spotted Owl Occupancy and Reproduction on the Rodeo-Chediski Fire, Arizona
  Michael A. Lommler; Joseph L. Ganey; Paul Beier; Jamie S. Sanderlin; Samuel A. Cushman
Wildland fire is considered a potential factor affecting the Mexican spotted owl (Strix occidentalis lucida) in the United States but the influence of large, high-severity fire is highly contested in the literature. While patches of high-severity fire may provide foraging habitat for spotted owls, extensive areas burned at high-severity may leave little nesting and roosting habitat available for colonization. Our objective was to evaluate the effects of the 2002 Rodeo-Chediski fire (187,000 ha, 37% burned at high severity) on spotted owls. Our study area covered 18000 ha of burned area on the Apache-Sitgreaves and Tonto National Forests. Before the fire (1990-1998) an average of 9 owl pairs (maximum 14) occupied this area. We surveyed this area intensively during the 2014-2016 breeding seasons and observed an average of 5 pairs (maximum 6). We also observed a post-fire decline in average reproduction from 7 fledged young per year to 2 fledged young per year. Occupancy modeling indicates that increased fire severity is correlated with reduced occupancy probability. Our study supports previous suggestions that “megafires” present a serious risk to spotted owls.
4:20PM Effects of Fuel Treatments on Spotted Owls: Current Knowledge and Future Directions
  M. Zachariah Peery; Gavin Jones; R.j. Gutierrez
Fuel treatments that reduce the spread and intensity of large, high-severity forest fires by removing surface and ladder fuels may have detrimental impacts on spotted owls by simplifying forest structure, yet benefit this species by reducing fire-related loss of habitat. Assessing these trade-offs in a manner that provides a rigorous scientific basis for implementing treatments on owls and their habitat, however, is challenged by ecological uncertainties and methodological constraints. Here, we discuss the empirical basis, analytical methods, and results of recent studies that have evaluated the potential effects of fuel treatments on spotted owl habitat and populations. We also highlight how emerging research on the effects of fire on spotted owls, as well as fire behavior and animal population modeling advances, can be harnessed to improve the assessment of trade-offs associated with fuel treatments. Nevertheless, we suggest scientific uncertainties are likely to persist such that decisions about the location, scale, intensity, and pace at which fuel treatments are implemented will benefit from the collective expert opinion of wildlife, forest, and fire ecologists. These uncertainties highlight the need for carefully designed adaptive management frameworks that can yield insights into the effects of future fuel treatments on spotted owls at landscape and regional scales.
4:40PM The Role of Fire in Spotted Owl Biology: A Synthesis of the Current State of Knowledge
  William M. Block; Kevin McKelvey

 
Organizers: William M. Block, US Forest Service, Rocky Mountain Research Station, Flagstaff, AZ; Joseph L. Ganey, US Forest Service, Rocky Mountain Research Station, Flagstaff, AZ; R. J. Gutiérrez, University of Minnesota, McKinleyville, CA; Shaula Hedwall, US Fish and Wildlife Service, Flagstaff, AZ; Serra Hoagland, US Forest Service, Rocky Mountain Research Station, Pablo, MT
 
Supported by: US Forest Service, Southwestern Region, Southwest Fire Sciences Consortium

Symposium
Location: Albuquerque Convention Center Date: September 25, 2017 Time: 10:30 am - 5:00 pm