Breaking Down the Burn

Figure 1. Low severity burn example. Source: National Interagency Fire Center

ildfire is a natural part of our landscapes in BC and across North America, with a long track record of supporting healthy ecosystem functions. Science and on-the-land observations have shown natural levels of fire to have a plethora of beneficial effects, including increasing understory plant production (great for animal forage), suppressing invasive species, supporting seed germination in some native plants & trees, and maintaining healthy tree densities. Our ecosystems are not static: some of the most foundational components of wildlife habitat, such as forage, tree cover, and movement corridors are drastically shaped and changed by disturbances including fire. Our fire-adapted ecosystems need periodic burning to maintain these characteristics [1]. How an area responds to fire depends on the type of ecosystem and the severity of the fire. For example, Interior Douglas-fir systems have evolved to have regular, low-severity wildfires, but a severe wildfire can occur if regular fires are not maintained in these areas. Instead of frequent, gentle wildfires bringing increased understory plant production, we might see an occasional severe wildfire burn off the organic layer of the soil altogether and cause damage to the seedbank, meaning the system will take longer to recover. If you’re interested in understanding the shifting Interior Douglas-fir landscape, check out this interactive story map by researcher Spencer Bronson: https:// storymaps.arcgis.com/stories/ c0a1bc0538684ee799c8c72d56ebb13e. Humans have long been a part of maintaining wildfire on the landscape. Indigenous people have historically (and still to this day) carefully managed forage crops for both humans and wildlife through regular cultural burning practices. These practices usually have goals of supporting overall ecosystem health and balance, improving wildlife habitat, increasing forage food crops such as medicinal and culinary plants, and reducing natural wildfire risk to communities [2, 3] (Figure 2). Recent research has also pointed to the role of Indigenous people’s contribution to fire regimes as critical to both ecology and culture [4]. Keeping “natural” levels of wildfire on the land (supporting the historical fire regime) ensures that these systems – which evolved with varying levels of fire to support healthy function – stay in tip-top condition to support the animals that depend on them. Understanding the natural fire regime of a forest is important to guide management actions like mechanical harvesting, prescribed burning, and Indigenous fire stewardship [5]. The research on wildfire within BC universities alone is immense. There are fire ecology labs and experts at every major institution in our province, investigating foundational research and designing innovative solutions on fire’s natural role in ecosystems and how to bring it back to the land in a healthy way that supports modern land-use objectives. There are many examples, but I’ll just highlight a few local favourites. In a 2021 study, researchers at UBC found that certain types of forest harvesting in mule deer habitat can be compatible with complex disturbance regimes such as wildfire [6]. Researchers at UBCO recently showed in 2019 that fire size is a

Figure 2. A seasonal calendar illustrating aspects of Indigenous fire stewardship. Image concept by K.M. Hoffman and A.C. Christianson, design and illustration by Alexandra Langweider of Align Illustration. [2]

Figure 3. Three years post-fire vegetation growth in part of the Elephant Hill fire. Photo: Josh Batson

great predictor of snowshoe hair relative abundance, emphasizing the importance of these regenerating sites for hares after large wildfires [7]. One finding from a 2022 study by the University of Victoria and others gave valuable insights into what type of plants dominate after different severity of burns, and found that the history of disturbance has an even bigger role to play in what grows back than just the most recent fire itself [8]. Of course, our friends south of the border are also working on excellent research; one example comes from a 2022 study where researchers in Arizona described how mixed-severity fires shape habitat use by a variety of wildlife [9]. In another example, one study by the US Forest Service found that during the spring and summer, Elk selected for habitat areas treated with prescribed fire for up to 14 years post-burn. By tracking elk with telemetry data over 22 years, this study also found that the patchwork of burnt and unburnt areas was important for elk, based on their needs at different times of year [10]. Since we’re in BC, let’s let forestry enter the conversation: there are elements of designing landscape-level forest management plans to follow this historical fire regime. This means managing the age-structure of the trees and the patch sizes of the blocks to essentially mimic that disturbance caused by wildfires [11]. Some prescriptions even called for logged areas to be burnt before tree planting. Though it still has its merits, forest harvesting leaves a lot to be desired in terms of its ability to mimic wildfire. In best practice, there must be a balance between all landscape tools (like prescribed burns, Indigenous fire stewardship, and harvesting) to make sure we are maintaining healthy landscapes and further, healthy wildlife habitat. I’d say it’s been demonstrated that the role of wildfire specifically in maintaining ecosystem health and function is well understood and studied. Even with this in-depth understanding, we are seeing a general lack of healthy fires on our landscapes. Why? Governments have historically campaigned (very successfully) for wildfire suppression across North America, with the idea of protecting communities and forest resources. If you need one example, just think of Smokey the Bear as a loveable public icon, drilling the message into us all that only you can prevent wildfires. There is some importance in his message not to undermine: we really don’t want cigarettes, campfires, and fireworks to initiate and exacerbate wildfires, and we also can’t deny the real safety risk of uncontrolled wildfires near our communities. But these messages also proliferated a public standard on controlling and putting out all wildfires that naturally occurred on the land. This action, based primarily on safety and economics, largely halted prescribed burns as a management tool. Further, the very fire suppression aimed to keep

people safe has led to greater risk to communities by allowing fuels to build up beyond natural levels. When fires do come to these areas, they burn more severely than the system has evolved to tolerate. I’m sure there are many readers out there who have experienced first-hand the devastating impacts of some of the severe wildfire seasons BC has seen in recent years. It’s understandable the fear associated with wildfire, but science is teaching us that increasing prescribed burns, and supporting some natural burns, has an overall positive effect by not only protecting our communities but also supporting our landscapes. Moving forward, we are seeing pathways open within our government systems to allow for more prescribed burning projects. There is a growing appetite from the provincial government to partner with organizations, Indigenous groups, and communities to execute local projects. The Forest Enhancement Society (FESBC) is one mechanism that provides support to a wealth of projects related to forest resource enhancement in BC, many of which include prescribed burning. FESBC supports “indigenous groups, local communities, contractors and companies to implement innovative forestry projects that reduce greenhouse gases, protect communities from wildfire, improve wildlife habitat, and create jobs for British Columbians”. You can check out an interactive map of all FESBC projects here, and filter to the ones specific to habitat enhancement or wildfire risk reduction: https:// www.fesbc.ca/projects/ (note: not all habitat enhancement projects by FESBC include burning). The Ministry and several partners (including WSSBC) are also working on prescribed burning in the Kootenays to enhance Bighorn sheep habitat and support herd health [12]. We’re also seeing new programs that grant rights

Figure 4. Prescribed Fire in Northern British Columbia to improve Stone’s Sheep habitat, May 2022. Credit: Josh Hamilton.

back to First Nations to conduct cultural burning on their traditional territories – another huge step towards restoring healthy wildfire on the land.

The science on fire is clear, but on a project by project case, how can we monitor the success of

these burns? People on the land observing the impacts is awesome, but it’s ideal to include scientific approaches to monitoring too. One really great option for designing a monitoring program is the tried and true before and after control impact design. Surveying burnt and unburnt areas both before and after a treatment gives a great reference on the impacts of a burn. We should consider evaluating both habitat quality, such as surveying specific plants or communities of plants (diversity, density, biomass, etc.) or wildlife use of an area (using satellite collar data or wildlife camera data). I can’t talk about prescribed burn projects to the WSSBC audience without exploring the fantastic work the Society and its partners are doing on several burns right here in BC. The Stone’s Sheep Habitat Enhancement project that has been underway for three years in Northeastern BC is one example I think we’re all very excited about. The objectives of this project are to “improve forage quality and quantity, remove the ingress of trees and woody vegetation, and increase the line-of-sight for better predator detection” [13]. In May of 2022, approximately 160 hectares of winter range was treated, with a goal of the long-term program to treat 500-1000ha of Stone’s sheep

Figure 5. Setting up remote wildlife cameras to monitor pre and post burn wildlife activity. Credit: Josh Hamilton.

habitat every year. These efforts are being complimented by an effectiveness monitoring program, using remote wildlife cameras and vegetation plots both pre and post treatment. There are many additional research opportunities that can arise from projects like this. For those of you that caught the article “Science-based wildlife management: what is it and why does it matter” on pages 16-18 of the Summer 2022 issue of this very magazine, you might already be recognizing some important aspects of good science-based management here (and for those of you that didn’t read that article, you’ve just assigned yourself some further reading!). The design of this burn prescription is detailed in science-backed knowledge of where fire can achieve certain vegetation objectives, fire ecology and behaviour, and more. It’s a collaborative and transparent project, and it even includes a monitoring program to determine its successes and improve the design for the future. Because fire has holistic and broadly reaching landscape impacts, we generally see a benefit to all species in the system when fire is brought back to a system where it would naturally occur. This is great news for all wildlife and people that depend on these landscapes, not just one focal species (Stone’s sheep in this case). Now for the curveball. It’s not just fire suppression and subsequent fuel loading contributing to the imbalance of fire on the land. The effects of climate change are also driving significant changes to the severity and frequency of wildfires. This is an unfortunate feedback loop – where wildfires are releasing massive amounts of carbon and greenhouse gases that are stored in forests, furthering exacerbating climate change. A 2022 study in Alaska suggests that some fire management (including suppression) is actually needed to manage stored carbon in the boreal forest [14]. The history and science behind wildfire is complex to say the least. What’s exciting is we are now in a paradigm shift: we still need to protect our communities and ecosystems from wildfires, which appear to be increasing in frequency and severity with climate change, but we are also recognizing and supporting fire as a tool to do this important work.

Sydney is a wildlife researcher and forestry professional (non-practicing), with a degree in Natural Resource Science. She is currently working on her Master of Science degree at the University of Victoria, where she is partnered with Gwich’in organizations, studying Dall’s sheep and mammal community ecology in the Northern Richardson Mountains, NWT. She is also currently working on BC’s Thinhorn Sheep Stewardship Framework, as part of the Indigenous perspectives working group. Born and raised in the Interior of BC, Sydney is an active hunter, fly fisher, forager, wildlife photographer, and overall backcountry enthusiast.

References

1. Saladyga, T., K.A. Palmquist, and C.M. Bacon, Fire history and vegetation data reveal ecological benefits of recent mixed-severity fires in the Cumberland

Mountains, West Virginia, USA. Fire Ecology, 2022. 18(1): p. 1-20. 2. Hoffman, K.M., et al., The right to burn: barriers and opportunities for Indigenous-led fire stewardship in Canada. FACETS, 2022. 7(1): p. 464-481. 3. Christianson, A., Social science research on Indigenous wildfire management in the 21st century and future research needs. International Journal of

Wildland Fire, 2014. 24(2): p. 190-200. 4. Copes-Gerbitz, K., L.D. Daniels, and S.M. Hagerman, The contribution of Indigenous stewardship to an historical mixed-severity fire regime in British

Columbia, Canada. Ecological Applications, 2022. 5. Brookes, W., et al., A disrupted historical fire regime in central British Columbia. Frontiers in Ecology and Evolution, 2021. 9: p. 420. 6. Leclerc, M.-A.F., L.D. Daniels, and A.L. Carroll, Managing wildlife habitat: Complex interactions with biotic and abiotic disturbances. Frontiers in Ecology and Evolution, 2021. 9. 7. Hutchen, J. and K.E. Hodges, Impact of wildfire size on snowshoe hare relative abundance in southern British Columbia, Canada. Fire Ecology, 2019. 15(1): p. 1-12. 8. Halpern, C.B. and J.A. Antos, Burn severity and pre-fire seral state interact to shape vegetation responses to fire in a young, western Cascade Range forest. Forest Ecology and Management, 2022. 507. 9. Lewis, J.S., et al., Mixed-severity wildfire shapes habitat use of large herbivores and carnivores. Forest Ecology and Management, 2022. 506. 10. Spitz, D.B., et al., Fire history influences large-herbivore behavior at circadian, seasonal, and successional scales. Ecological Applications, 2018. 28(8): p. 2082-2091. 11. Bunnell, F.L., Forest-dwelling vertebrate faunas and natural fire regimes in British Columbia: Patterns and implications for conservation. Conservation

Biology, 1995. 9(3): p. 636-644. 12. Wild Sheep Society of BC. Projects. 2022; Available from: https://www.wildsheepsociety.com/wild-sheep-society-of-bc-projects/. 13. Ridgeline Wildlife Enhancement, Stone’s sheep habitat enhancement. 2022. https://www.wildsheepsociety.com/stones-sheep-habitat-enhancementaugust-2022-newsletter/ 14. Phillips, C.A., et al., Escalating carbon emissions from North American boreal forest wildfires and the climate mitigation potential of fire management.

Science advances, 2022. 8(17).