Study: Spatial patterns and rarity of the white‐phased ‘Spirit bear’ allele reveal gaps in habitat protection

These findings provide new insight into hypotheses related to the maintenance of this rare polymorphism, and directly relevant information to support evidence‐based opportunities for Indigenous Nations of the area to attend to gaps in conservation planning.

Juvenile Spirit bear and black bear mother stand by a river with salmon strewn across the bank.

Photo by Doug Neasloss, Resource Stewardship Director for the Kitasoo/Xai’xais Nation, and co-author on this paper.

Spirit bears are rarer and less protected than we thought.

New research has identified that the small genetic change responsible for Spirit bears – a rare, white-coated form of black bears – is up to 50% rarer in the Great Bear Rainforest than previously estimated. The study also indicates that geographic hotspots, where the Spirit bear version of the gene was especially prominent lack adequate protection from resource extraction.

This research paper, published by British Ecological Society, will inform contemporary land use planning, which include the potential for increased protection in the form of Indigenous Protected Areas. Lead author Christina Service published these findings with team members from the Kitasoo Xai’xais Stewardship Authority, Gitga’at Oceans and Lands Department, University of British Columbia, University of Victoria, and Raincoast Conservation Foundation.

“We found that the frequency of the white version of the gene was as much as 50% lower compared with previous estimates. While ongoing work is estimating the number of Spirit bears in the area, such a finding questions previous estimates.” – Christina Service, Wildlife Biologist for Kitasoo/Xai’xais First Nation Stewardship Authority, Raincoast Applied Conservation Science Lab

Citation

Service CN, Bourbonnais M, Adams MS, et al. Spatial patterns and rarity of the white-phased ‘Spirit bear’ allele reveal gaps in habitat protection. Ecol SolutEvidence. 2020;e12014. https://doi.org/10.1002/2688-8319.12014

Abstract

1. Preserving genetic and phenotypic diversity can help safeguard not only biodiversity but also cultural and economic values.

2. Here, we present data that emerged from Indigenous‐led research at the intersection of evolution and ecology to support conservation planning of a culturally salient, economically valuable, and rare phenotypic variant. We addressed three conservation objectives for the white‐phased ‘Spirit bear’ polymorphism, a rare and endemic white‐coated phenotype of black bear (Ursus americanus ) in Kitasoo/Xai’xais and Gitga’at Territories and beyond in coastal British Columbia, Canada. First, we used non‐invasively collected hair samples ( = 385 bears over ∼18,000 km2) to assess the spatial variation in the frequency of the allele that controls the white‐coloured morph (mc1r). Second, we compared our observed allele frequencies at mc1r with those expected under Hardy–Weinberg equilibrium. Finally, we examined how well current protected areas in the region aligned with spatial hotspots of Spirit bear alleles.

3. We found that landscape‐level allele frequency was lower than previously reported. For example our systematic sampling estimated a frequency of 0.25 (95% CI {0.13, 0.41}) on Gribbell Island compared with the previously reported estimate of 0.56. Also, in contrast with previous reports, we failed to detect a statistically significant departure from Hardy–Weinberg equilibrium at mc1r, which calls into question the previously posited role of homozygote gene flow, heterozygote disadvantage, and positive assortative mating in the maintenance of this polymorphism. Finally, we found a discrepancy between the placement of protected areas and the 90th percentile hotspots (upper 10% of all estimated values) of Spirit bear alleles, with ∼50% of hotspots falling outside of protected areas.

4. These results provide new insight into hypotheses related to the maintenance of this rare polymorphism, and directly relevant information to support evidence‐based opportunities for Indigenous Nations of the area to attend to gaps in conservation planning.

Select figures and assets

Figure 1

Study area (2012–2017) and corresponding communities in coastal British Columbia, Canada. Coloured polygons indicate each unique landmass for spatial scale A, and the solid line indicates the extent of spatial scale B (see Methods).

Figure 3

Map from spirits bears study comparing conservancies with hotspots.
Comparison between protected areas (‘Conservancies’), and percentiles (10th to ≥90th) of G allele frequency of black bears (Ursus americanus ) as estimated by cost‐weighted kriging of allele ratio (n = 988 alleles) across 175 sampling sites in coastal British Columbia, Canada (2012–2017).

Affiliations

Gitga’at Oceans and Lands Department, Gitga’at First Nation, Hartley Bay, British Columbia, Canada

Kitasoo Xai’xais Stewardship Authority, Kitasoo/Xai’xais First Nation, Klemtu, British Columbia, Canada

Department of Geography, University of Victoria, Victoria, British Columbia, Canada

Department of Earth, Environmental and Geographic Sciences, Irving K. Barber School of Arts and Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada

Raincoast Conservation Foundation, Sidney, British Columbia, Canada