| Literature DB >> 25054635 |
Christina N Service1, Megan S Adams2, Kyle A Artelle3, Paul Paquet4, Laura V Grant5, Chris T Darimont1.
Abstract
Range shifts among wildlife can occur rapidly and impose cascading ecological, economic, and cultural consequences. However, occurrence data used to define distributional limits derived from scientific approaches are often outdated for wide ranging and elusive species, especially in remote environments. Accordingly, our aim was to amalgamate indigenous and western scientific evidence of grizzly bear (Ursus arctos horribilis) records and detail a potential range shift on the central coast of British Columbia, Canada. In addition, we test the hypothesis that data from each method yield similar results, as well as illustrate the complementary nature of this coupled approach. Combining information from traditional and local ecological knowledge (TEK/LEK) interviews with remote camera, genetic, and hunting data revealed that grizzly bears are now present on 10 islands outside their current management boundary. LEK interview data suggested this expansion has accelerated over the last 10 years. Both approaches provided complementary details and primarily affirmed one another: all islands with scientific evidence for occupation had consistent TEK/LEK evidence. Moreover, our complementary methods approach enabled a more spatially and temporally detailed account than either method would have afforded alone. In many cases, knowledge already held by local indigenous people could provide timely and inexpensive data about changing ecological processes. However, verifying the accuracy of scientific and experiential knowledge by pairing sources at the same spatial scale allows for increased confidence and detail. A similarly coupled approach may be useful across taxa in many regions.Entities:
Mesh:
Year: 2014 PMID: 25054635 PMCID: PMC4108310 DOI: 10.1371/journal.pone.0101595
Source DB: PubMed Journal: PLoS One ISSN: 1932-6203 Impact factor: 3.240
Figure 1Spatial pattern of evidence of island occupancy and detection type.
a) Weight of evidence of grizzly bear (Ursus arctos horribilis) occupancy at the island scale within Heiltsuk and Kitasoo/Xai'xais Territories in coastal British Columbia, Canada. Each data type (local ecological knowledge observation, mortality record, genetic ID and remote camera observation) was weighted equally to provide an indication of occupancy rather than bear density. Dark grey areas were not included in our study. The ‘current management boundary' is the westward (i.e., seaward extent) of the Province of British Columbia's Grizzly Bear Population Units, the spatial scale at which grizzly bears are managed in the province. Spatial pattern in data types used to detect grizzly bears (Ursus arctos horribilis) in sampled areas within Heiltsuk and Kitasoo/Xai'xais Territories. Eighteen islands were included in the study.
Figure 2Time series of island grizzly bear occupation over three time periods.
Local residents' perception of grizzly bear (Ursus arctos horribilis) distribution throughout Heiltsuk and Kitasoo/Xai'xais Territories in coastal British Columbia, Canada during the Pre 1992 (traditional ecological knowledge data), 1992–2002 (local ecological knowledge data) and 2003–2012 (local ecological knowledge data) time periods. Data are reported at the island scale (n = 18 islands) as the percentage of participants who indicated the island was within their area of observation and supported grizzly bears. Dark grey areas were not included in our study and the ‘current management boundary' is the westward (i.e., seaward extent) of the Province of British Columbia's Grizzly Bear Population Units, the spatial scale at which grizzly bears are managed in the province.
Detections of island grizzly bears (Ursus arctos horribilis) by data type (presented as raw observations and as detection-per-unit-effort (DPUE) values) within Heiltsuk and Kitasoo/Xai'xais Territories in coastal British Columbia, Canada (n = 18 islands).
| Island | Total Remote Camera Observations | Remote Camera Detections Per Trap Night | Total Hair Snag Observations | Hair Snag Year | Hair Snag Detections Per Trap Night | LEK Observations | Total Sow/Cub Observations | Mortality Observation |
|
| - | - | - | - | - | 0 | 0 | 0 |
|
| - | - | - | - | - | 0 | 0 | 0 |
|
| - | - | 0 | - | - | 6 | 0 | 0 |
|
| - | - | 2 | 2009–2012 | 0.03 | 6 | 0 | 0 |
|
| - | - | 1 | 2009–2012 | 0.01 | 7 | 3 | 0 |
|
| - | - | 0 | 2009–2012 | 0 | 5 | 0 | 0 |
|
| - | - | - | - | - | 1 | 0 | 0 |
|
| - | - | - | - | - | 0 | 0 | 0 |
|
| - | - | - | - | - | 1 | 0 | 1 |
|
| - | - | 1 | 2009–2012 | 0.04 | 12 | 4 | 0 |
|
| - | - | - | - | - | 1 | 0 | 0 |
|
| 7 | 0.02 | 0 | 2012 | 0.01 | 15 | 0 | 0 |
|
| 0 | 0 | 0 | 2012 | 0 | 1 | 0 | 0 |
|
| 19 | 0.03 | 3 | 2012 | 0.02 | 16 | 17 | 1 |
|
| 1 | 0.01 | 0 | 2012 | 0.01 | 12 | 3 | 1 |
|
| - | - | - | - | - | 9 | 3 | 0 |
|
| - | - | - | - | - | 2 | 0 | 0 |
|
| 1 | 0.03 | 1 | 2012 | 0.03 | 22 | 15 | 0 |
For islands with remote cameras.
For islands with hair snags.
Indicates number of observations, not number of individual grizzly bears, across study period.
Summed across seasons and years.
** Indicates islands within the current management boundary'.
Sampling effort of island grizzly bears (Ursus arctos horribilis) by data type within Heiltsuk and Kitasoo/Xai'xais Territories in coastal British Columbia, Canada (n = 18 islands).
| Island | Number of Remote Cameras | Total Remote Camera Nightss | Number of Hair Snag Sites | Hair Snag Year | Total Hair Snag Nights | Number of LEK Interviewees Who Reported on Island | Average Number of Report Days Per Year |
|
| 0 | - | 0 | - | - | 13 | 120 |
|
| 0 | - | 0 | - | - | 9 | 120 |
|
| 0 | - | 0 | - | - | 14 | 142 |
|
| 0 | - | 2 | 2009–2012 | 159 | 14 | 142 |
|
| 0 | - | 4 | 2009–2012 | 304 | 14 | 142 |
|
| 0 | - | 2 | 2009–2012 | 178 | 13 | 148 |
|
| 0 | - | 0 | - | - | 13 | 148 |
|
| 0 | - | 0 | - | - | 9 | 120 |
|
| 0 | - | 0 | - | - | 12 | 146 |
|
| 0 | - | 3 | 2009–2012 | 221 | 15 | 145 |
|
| 0 | - | 0 | - | - | 14 | 137 |
|
| 3 | 357 | 3 | 2012 | 416 | 10 | 136 |
|
| 1 | 23 | 1 | 2012 | 23 | 13 | 140 |
|
| 9 | 661 | 9 | 2012 | 1217 | 8 | 140 |
|
| 4 | 192 | 3 | 2012 | 398 | 11 | 139 |
|
| 0 | - | 0 | - | - | 8 | 128 |
|
| 0 | - | 0 | - | - | 14 | 145 |
|
| 1 | 135 | 1 | 2012 | 121 | 11 | 140 |
For islands with remote cameras.
Across entire study period.
Average number of ‘report days’ (i.e., days interviewees reported on for each island) per year from 1992–2012. Data derived from all participants who included.
the island in their area of expertise.
** Indicates islands within the “current management boundary”.
Figure 3Trend of island grizzly occupation over time as derived from LEK data.
Yearly number of island grizzly bear (Ursus arctos horribilis) observations per unit survey effort (a summation of all participants' observations across all islands; local ecological knowledge data only) between 1992–2011 in the Traditional Territories of the Heiltsuk and Kitasoo/Xai'xais First Nations in British Columbia, Canada. These observations encompass islands within and outside the current management boundary (n = 18 islands).