Course:CONS200/2020/An Evaluation of the Conservation for the Spotted Owl in British Columbia

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The Strix occidentalis caurina (Northern Spotted Owl) is a species of owl which inhabits areas of Western North America. The species experiences a range of threats to its survival, and the entire species population is currently considered to be 'Near Threatened', according to the IUCN Red List[1]. A variety of conservation efforts have been made throughout British Columbia, with varied effectiveness.

Northern Spotted Owl (Strix Occidentalis Caurina)

Background and Ecology

Figure 1: Range of Strix occidentalis caurina shown in light gray

Strix occidentalis caurina can be found throughout the Pacific Northwest, their range illustrated by Figure 1. Occupies a small range in southeastern British Columbia, in old-growth Douglas fir forests. Such forests provide nest sites, prey and protection from predators[2]. Strix occidentalis caurina is unique from other owl species throughout Pacific forest areas, as they are restricted to small and specific habitat zones[2].The diet of Strix occidentalis caurina consists of small mammals, such as the Northern Flying Squirrel and Deer Mouse[2]. Forest areas which have been cleared within 20 years are not used for hunting by Strix occidentalis caurina, indicating a strong preference for old-growth forests[2]. Reproduction of the Strix occidentalis caurina occurs monogamously. Adult pairs of Strix occidentalis caurina remain together and occupy the same home range of approximately 32 square kilometres for life[2]. Nests are located in already present sites within home ranges caused by broken tree tops or rot in trees.

Communication amongst populations is important for the survival of the species. Strix occidentalis caurina have the ability to learn the calls of other species close to or within their habitat, and adjust their own calls accordingly so as to avoid conflict or confusion[2].

Conservation Threats to Strix Occidentalis Caurina

A significant threat to the population of Strix occidentalis caurina in British Columbia can be attributed to the loss of its native habitat through deforestation. In particular, Strix occidentalis caurina requires dense old-growth forests, which readily have available naturally occurring nest sites, such as broken tree tops or cavities, and provide appropriate thermal cover, protection from predators, and availability of prey[3]. Such old-growth forests are particularly desired by timber companies as they possess qualities of stronger wood and denser grains, and as a result are more economically valuable[4]. Currently, it is estimated that only 1 per cent of British Columbia's original old-growth Douglas fir remains[5].

Another significant threat to Strix occidentalis caurina in British Columbia is negative competition from invasive species, such as the Barred Owl (Strix varia). The habitat range of Strix varia has expanded from its historic range in eastern North America to now overlap with that of the Strix occidentalis caurina in southwestern British Columbia[6]. Research has found that the relative population of Spotted Owls declines where Spotted Owl habitats are invaded by populations of Strix varia[6]. Barred Owls are larger in size than Strix occidentalis caurinas and display more aggressive behaviour. Additionally, Strix varia demonstrates greater resilience to habitat quality declines, due to a broader diet than that of Strix occidentalis caurina. In an already declining quantity and quality of habitat, presence of Strix varia populations increase habitat competition and excludes Strix occidentalis caurina populations[7].

History of Conservation in the Pacific Northwest

Figure 2: Volume of Pacific Northwest Douglas-fir and hemlock exports to all countries

The first forest management plan developed with the conservation of the Strix occidentalis caurina (Northern Spotted Owl) as a primary goal was the Northwest Forest Plan (NWFP). The final version of this plan was passed in 1994 beneath the Clinton administration after years of political and legal debates between loggers and conservationists[8]. This plan The passing of the NWFP followed growing concerns of over-harvesting and intensive management of old-growth forests in the Pacific Northwest, practices which had adverse impacts on Strix occidentalis caurina populations in the Pacific Northwest[9]. The logging industry experienced a peak in the late 1980s, shown in Figure 2, leaving the Pacific Northwest mountains and forests unmistakably marked by the scars of clear-cutting practices. This loss of habitat for the Strix occidentalis caurina greatly attributed to 1990 listing of the species as "threatened" under the US Endangered Species Act, and subsequently motivated the proposal of the NWFP (1990)[9].

The Northwest Forest Plan ended clear-cutting forest management practices in the Pacific Northwest, specifically in Washington, Oregon, and Northern California, affecting a total 10 million acres of federal land[10]. The plan was a point of much contention as it led to the loss of many logging and milling jobs[11]. In order to analyze the impact of the plan on biodiversity, bird populations have been closely monitored, as they are a commonly used biodiversity indicator. And while the implementation of the plan greatly reduced loss of old-growth forest, losses to wildfire have increased, and so did loss of bird populations associated with older forests. These continued declines can be attributed to the losses due to fire and sustained clear-cutting of forest range on private lands[10].

In British Columbia species the Strix occidentalis caurina is designated at Endangered by the COESWIC and Red-listed by the BC Wildlife Branch. Species management of the Northern Spotted Owl went into effect under the Spotted Owl Management Plan (SOMP), implemented in 1997 in BC’s Chilliwack and Squamish Natural Resource Districts[12]. The initial plan, now known as SOMP, has since been revised and is now referred to as SOMP2. The general goal of the plan aims at creating, enhancing, or maintaining a sufficient quantity/quality of forest habitat range for the Strix occidentalis caurina, by establishment of Special Resource Management Zones (SRMZs) over a span of 363,000 hectares[13].

Current Conservation Approaches in British Columbia

Under the previous management plan SOMP 1, the Strix occidentalis caurina's (Northern Spotted Owl) population was still experiencing a large decrease in numbers which was brought to the attention of the federal and

Figure 3: Map of Areas for Spotted Owl Management in the Chilliwack, Squamish and Cascades Forest Districts

provincial governments in the form of the Recovery Strategy for the Northern Spotted Owl (RSNSO) for review[14]. This strategy lead to the current methods of rebuilding the Strix occidentalis caurina's population through new methods, re-evaluating the SOMP 1, and its SRMZ, along with the protection of Strix occidentalis caurina locations by establishing nine wildlife habitat areas (WHA)[14]. One of the methods for rebuilding the Strix occidentalis caurina's population formed from the RSNSO was a captive breeding and release program initiated in 2007 which had a foundation of six adult Spotted Owls[15]. As of 2016, the Strix occidentalis caurina's population has increased to seventeen; eight of which had been born in captivity[16]. The goal of the breeding program is to hold ten breeding pairs of Strix occidentalis caurina's with the hope of them annually producing around 15-20 offspring to release into the wild each year and the first year of release was the spring of 2018[16]. Another method is the management of Strix varia (Barred Owl) as they encroach into Strix occidentalis caurina's habitats[17]. The provincial Forests and Lands Ministry has relocated 73, and authorized the shooting of 39 Strix varia as they push the Strix occidentalis caurinas out of the few areas of old growth forest under protection from logging companies[17]. The other two methods that have been put into action are supplemental feeding and the relocation of Strix occidentalis caurina to stable habitat zones, both of which have little reserch into their employment and effect[14]. The RSNSO also lead to the re-evaluation of the SOMP 1 into the SOMP 2 which is more efficient in its protection for Strix occidentalis caurina's habitat within timber supply areas with a no-net loss policy[14]. The SRMZ outlined within the SOMP 1 were revised into the SOMP 2 which created two new designations: Long-Term Owl Habitat Areas (LTOHA) and Managed Future Habitat Areas (MFHA)[14]. The LTOHA’s intent is to preserve the current Strix occidentalis caurina habitats, old growth forests, and work towards the development of new areas of old growth through natural causes or habitat enhancement practices[14]. Over time this will increase the quality and abundance of the Strix occidentalis caurina's habitats allowing for the owls to develop a proper nesting ground within them[14]. The MFHA will work towards maintaining the logging industry while protecting the Strix occidentalis caurina's habitats[14].This is done by the protection of key trees or snags within old growth forests that are being logged[14].This is done in areas with a 60-100 year rotation which will allow old growth forest components (Mother trees, snags & other old growth forest indicators) to exist in a younger stand of trees allowing for the Strix occidentalis caurina to survive in the area after logging[14]. These changes to the SRMZ within the revised SOMP 1 now fall under the name SOMP 2 which is our current management plan within B.C.[14]. The WHA is also currently in effect protecting approximately 23,000 ha over nine separate locations of Strix occidentalis caurina habitat, this management plan protects 100% of the forested area within the WHA[14].

Current Conservation Status

According to the British Columbia Wilderness Committee, there is approximately six Strix occidentalis caurina or spotted owls found in the wilderness. [18] In 1998 The British Columbia Ministry of Environment, Lands and Parks stated that there was approximately 4000 adult pairs of the Strix Occidentalis Caurina in the Pacific Northwest, and about 100 pairs, exclusively  within British Columbia [19]. The number of Strix occidentalis caurina has decreased drastically and is on the verge of extinction. This is because of major habitat destruction caused by deforestation and over logging of old-growth forests, which the Strix occidentalis caurina depends on for survival. Due to the extremely low adult population rates, the Strix occidentalis caurina, is considered as “endangered or threatened under the British Columbia Wildlife Act” (Dupius)[20]. The Conservation Data Center of the BC Ministry of Sustainable Resource Management uses a scale consisting of  numerical rating as well as different colour classes. Yezerinac and Moola (2006) explain that the scale goes from one to five with 1 being critically imperiled and 5 meaning secure. The colour categories are broken into Red, meaning endangered, Blue representing special concern and lastly yellow, demonstrating apparently secure.[21] Based off of the different rankings, it is apparent that the Strix occidentalis caurina is in critical endangerment, being placed into the red colour category. We as people, must put more effort into helping reduce the damage which we have already caused towards British Columbia’s lush ecosystem, and do everything in our power to ensure that the Strix occidentalis caurina continues to thrive, as well as an array of other species which are also endangered due to human interference on the environment.

Recommendations for Future Conservation

As briefly mentioned above, the Strix occidentalis caurina or Northern Spotted Owl can be found in habitats with older tree growth. One way conservation has occurred is through the Northwest Forest Plan (NWFP).[22]  Dunk, Woodbridge, Schumaker,et. al (2019) have determined that because of the Northwest Forest Plan developed by the National Forest Management Act of 1976, protected land has doubled. [23] Thus, being a direct result in Strix occidentalis caurina’s habit being more protected. The main way in which we can help prevent the extinction of the Northern Spotted Owl, is to always practice sustainable logging for all forest areas, not just the ones the are protected under the law.[24] Everyone needs to make a conscious effort in being more sustainable in their timber consumption and make little changes on a daily basis.

Despite the efforts of multiple different groups and organization, the Strix occidentalis caurina population has not increased enough to prevent the risk of extinction. The best and most efficient way which we can protect Strix occidentalis caurina is to continue to protect certain forest areas where the Strix occidentalis caurina lives and prevent further forest destruction.[25] We must go to the root of the problem and prevent the practices of unsustainable logging and remove human activity. The British Columbia Government may need to shut down lumber operations in the areas which the Strix occidentalis caurina is found, even if that means the province might experience an economic deficit. [26]If people are no longer allowed to harvest natural resources from the habitat of the Strix occidentalis caurina then there will be a greater chance for the Strix occidentalis caurina to come off of the endangered species list and prevent extinction.

Although conservation of protected areas has been somewhat effective in the preservation of the Strix occidentalis caurina, there is still a significant amount of other mechanisms that could be implemented to ensure the survival of this amazing bird. Some mechanisms that are not as traditional as ones mentioned previously include translocation and assisted migration. [27]Assisted migration is the translocation of the Strix occidentalis caurina to another habitat or ecosystem entirely. The only main issue with this however is finding a protected area in which the Strix occidentalis caurina could thrive and not experience the same obstacles as it's previous environment.[28] Another conservation mechanism that could be implemented is the addition of captive Strix occidentalis caurina in the wild. There are some issues with this because the owls may not know how to survive in the wild if they lived their entire lives in captivity. However there are many positive benefits to this as well.[29] Firstly, the number of owls could rapidly increase allowing for more in the wild and these once captive owls could begin to breed with the wild ones. This would allow for greater genetic diversity within the species, considering there is only six or so in the wild.[30]

Ultimately, we as people need to make changes in our everyday lives if we want to help the Strix occidentalis caurina from extinction. We must change as much as we can, and make these changes as quickly as possible. There are somethings that we can do in our everyday lives, that will not only help the Strix occidentalis caurina but also the environment as a whole. [31]For example, one could ride their bike to work everyday rather than driving, if it is close and safe to do so, or using reusable bags and containers. The biggest thing that we can do as individuals is make choices in our everyday lives with the environment in mind. Rather than just consumer whatever products and not knowing where and how they were produced, we must consider the environment and if these products we consume have a negative impact on it.[32] Although it maybe be difficult at times to determine what is right from wrong and what is actually ethically produced, we all must make an effort to prevent further damage to the ecosystem and reduce our ecological footprint. We as individuals in society have a shared responsibility to determine whether the Strix occidentalis caurina, lives or dies, and its fate is dependent on the things that we do in our day to day lives. We need to make changes, not only to protect the Strix occidentalis caurina, but also to protect and preserve the thousands of other endangered species or other species that are on the edge of endangerment.


The Strix occidentalis caurina can be throughout the Pacific Northwest and is one of British Columbia's native species. This owl lives within the old growth of British Columbia's great rain forests and is critically endangered. According to recent statics there is approximately six of the Strix occidentalis caurina in the wild and that number will only decrease more if we don't do something quickly. This endangerment is caused by the practices of unsustainable deforestation and the introduction of invasive species. The Strix occidentalis caurina is currently found on the red list of endangered species. With certain government organizations and other independent wildlife groups such as the Committee on the Status of Endangered Wildlife in Canada or COESWIC, and the Northwest forest plan, these owls may have a fighting chance. If we all as individuals do our part to help maintain and respect the protected areas of the Strix occidentalis caurina or Northern Spotted Owl then it should be able to survive and move off the endangered species list.


COESWIC- Committee on the Status of Endangered Wildlife in Canada

LTOHA- Long-Term Owl Habitat Area

MFHA- Managed Future Habitat Area

NWFP- Northwest Forest Plan

RSNSO- Recovery Strategy of the Northern Spotted Owl

SOMP- Spotted Owl Management Plan

SRMZ- Special Resource Management Zone

WHA- Wildlife Habitat Area


  1. "Spotted Owl". IUCN Red List. Retrieved 7 April 2020.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Dupuis, L. The Northern Spotted Owl, The Northern Spotted Owl (1998). Victoria, BC. Retrieved from
  3. Dawson, William R.; et al. (Feb 1987). "Report of the Scientific Advisory Panel on the Spotted Owl". The Condor. 89: 205–229 – via JSTOR. Explicit use of et al. in: |first= (help)
  4. "Common Q&As About BC's Old-Growth Forests". Ancient Forest Alliance. 4 March 2020. Retrieved 4 March 2020.
  5. "'Indicative of a truly corrupt system;: government investigation reveals BC Timber Sales dilating old-growth logging rules". The Narwhal. 7 October 2019. Retrieved 4 March 2020.
  6. 6.0 6.1 Kelly, Elizabeth G.; et al. (Feb 2003). "Are Barred Owls Displacing Spotted Owls?". The Condor. 105: 45–53 – via JSTOR. Explicit use of et al. in: |last= (help)
  7. "Northern Spotted Owl". U.S. Fish and Wildlife Service. 8 January 2020. Retrieved 4 March 2020.
  8. Spies, Thomas (Aug 2019). "Twenty‐five years of the Northwest Forest Plan: what have we learned?". Frontiers on Ecology and the Environment – via esa.
  9. 9.0 9.1 Noon, Blakesley, Barry R., Jennifer A. (April, 2006). [ "Conservation of the Northern Spotted Owl under the Northwest Forest Plan"] Check |url= value (help). JStor. Check date values in: |date= (help)
  10. 10.0 10.1 Phalan, Benjamin T.; et al. (February 2019). "Impacts of the Northwest Forest Plan on forest composition and bird populations". PNAS – via Proceedings of the National Academy of Sciences of the United States of America. Explicit use of et al. in: |last= (help)
  11. Freudenburg, William R.; et al. (March 1998). "Forty Years of Spotted Owls? A Longitudinal Analysis of Logging Industry Job Losses". Sage Journals. Sociological Perspectives. Explicit use of et al. in: |last= (help)
  12. D’Anjou B., F.L.Waterhouse, M. Todd, and P. Braumberger. 2015. A systematic review of standlevel forest management for enhancing and recruiting Spotted Owl habitat in British Columbia. Prov. B.C., Victoria, B.C. Tech. Rep. 091.
  13. British Columbia. Vancouver Forest Region, & BC Environment. Lower Mainland Region. (1997). Spotted owl management plan : Summary report. Victoria: Ministry of Forests, Vancouver Forest Region ; Environment & Lands, Lower Mainland Region. Spotted owl management plan : summary report. (Book title)
  14. 14.00 14.01 14.02 14.03 14.04 14.05 14.06 14.07 14.08 14.09 14.10 14.11 "A component of the Spotted Owl Management Plan 2" (PDF). Best Management Practices For Managing Spotted Owl Habitat: 1–2. July 7, 2009.
  15. "Northern Spotted Owl Breeding Program".
  16. 16.0 16.1 "Northern Spotted Owl Recovery & Breeding Program".
  17. 17.0 17.1 Moore, Dene (January 27, 2013). "B.C. approves killing of barred owls to save endangered spotted owls". The Canadian press.
  18. "Spotted Owls Wilderness Committee". Wilderness Committee. Archived from the original on April.7/20. Check date values in: |archive-date= (help)
  19. Dupius, Linda (March 1998). "Northern Spotted Owl". Northern Spotted Owl. Archived from the original on March.14/20. Check date values in: |archive-date= (help)
  20. Dupuis, Linda (March 1998). "Northern Spotted Owl" (PDF). Northern Spotted. Archived from the original (PDF) on March.14/20. Check date values in: |archive-date= (help)
  21. S. Yezerinac &F. M. Moola. "Conservation status and threats to species associated with old-growth forests within the range of the Northern Spotted Owl (Strix occidentalis caurina) in British Columbia, Canada". Retrieved March.3/20. Check date values in: |access-date= (help)
  22. Regional Ecosystem Office. "Northwest Forest Plan". Northwest Forest Plan- Overview. Archived from the original on April.6/20. Check date values in: |archive-date= (help)
  23. Jeffrey R. Dunk ,Brian Woodbridge,Nathan Schumaker,Elizabeth M. Glenn,Brendan White,David W. LaPlante,Robert G. Anthony †,Raymond J. Davis ,Karl Halupka ,Paul Henson ,Bruce G. Marcot ,Michele Merola-Zwartjes ,Barry R. Noon , [ ... ],James Thrailkill; et al. "Conservation planning for species recovery under the Endangered Species Act: A case study with the Northern Spotted Owl". Retrieved March.3/20. Explicit use of et al. in: |last= (help); Check date values in: |access-date= (help)CS1 maint: multiple names: authors list (link)
  24. Weiting, Jens (May. 31 2019). "BC has entered extreme old-growth logging and we need to stop it". National Observer. Archived from the original on April. 5/20. Check date values in: |date=, |archive-date= (help)
  25. Forest, Ontario (April.5/20). "Forest Recovery Canada". Forest Recovery Canada. Archived from the original on |archive-url= requires |archive-date= (help). Check date values in: |date= (help)
  26. "Old Growth Wilderness Committee". Wilderness Committee. April.6/20. Archived from the original on |archive-url= requires |archive-date= (help). Check date values in: |date= (help)
  27. Bullock, J. M.; Hodder, K. H.; Manchester, S. J.; Stevenson (1997). "Review of information, policy and legislation on species translocation". Nerc Science of the enviroment. Archived from the original on |archive-url= requires |archive-date= (help).CS1 maint: multiple names: authors list (link)
  28. Olden, Julian (Nov.27/17). "Assisted Migration: Good Idea or Misguided hope". University of Washington Freshwater ecology. Check date values in: |date= (help)
  29. Samuel K. Wasser Kenneth Bevis Gina King Eric Hanson (March.6/03). "Northern Spotted Owls". The society for Conservation Biology. Check date values in: |date= (help)
  30. "Spotted Owl Wilderness Committee". Wilderness Committee. Archived from the original on |archive-url= requires |archive-date= (help).
  31. suzuki, David. "Top 10 things you can do about climate change". David Suziki Nature foundation. Archived from the original on |archive-url= requires |archive-date= (help).
  32. Dockrill, Peter (Feb. 25/17). "Consumers have a Bigger Impact". Science Alert. Archived from the original on |archive-url= requires |archive-date= (help). Check date values in: |date= (help)

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