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Name: 1967-ongoing - Caribou - Population Assessment - Itcha-Ilgachuz, Rainbows - Cariboo Region 
ID: 5955
Coordinator: Carolyn Shores; Nicola Dodd 
Funding Agency:
 
Region: Cariboo 
Security: Secure Some documents for this project are secured. Click on a secured document's filename to initiate a data request.
SurveysHelp (32 records)
Survey Name Survey Intensity Inventory Method Target Taxa
(Species Code / Scientific Name / English Name)  * = Primary Focus
2021 - Caribou - Aerial Late Winter Recruitment - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
1978-1987 - Caribou - Aerial Rut Composition - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
1994-2001 - Caribou - Aerial Rut Composition - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
2012 - Caribou - Aerial Post-Calving Population Count & Recruitment-MRR - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2012-2015 - Caribou - Aerial Late Winter Recruitment - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
2013 - Caribou - Aerial Rut Composition - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
2014 - Caribou - Aerial Post-Calving Population Count & Recruitment-MRR - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2014 - Caribou - Aerial Rut Composition - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
2016 - Caribou - Aerial Rut Population Count & Composition - Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2017 - Caribou - Aerial Post-Calving Population Count & Recruitment - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2018-2019 - Caribou - Aerial Post-Calving Population Count & Recruitment-MRR - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2020 - Caribou - Aerial Post-Calving Population Count & Recruitment-MRR - Itcha-Ilgachuz, Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2007 - Caribou - Aerial Rut Composition - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
2007-2008 - Caribou - Aerial Rut Population Count & Composition - Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2007-2010 - Caribou - Aerial Post-Calving Population Count & Recruitment - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2010 - Caribou - Aerial Late Winter Recruitment - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
1996-2004 - Caribou - Aerial Late Winter Recruitment - Itcha-Ilgachuz, Rainbows     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
1995-2001 - Caribou - Aerial Rut Population Count & Composition - Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
1996-2003 - Caribou - Post-Calving Population Count & Recruitment-MRR - Itcha-Ilgachuz, Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
1985-1988 - Caribou - Post-Calving Population Count & Recruitment-MRR - Itcha-Ilgachuz, Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
1986-1987 - Caribou - Aerial Rut Population Count & Composition - Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
1988-1992 - Caribou - Aerial Post-Calving Population Count & Recruitment - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
1994-1995 - Caribou - Aerial Post-Calving Population Count & Recruitment - Itcha-Ilgachuz, Rainbows     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
1967-1977 - Caribou - Aerial Reconnaissance - Rainbows     Presence/Not detected (possible)     M-RATA / Rangifer tarandus / Caribou* 
1973-1975 - Caribou - Ground Reconnaissance - Rainbows     Presence/Not detected (possible)     M-RATA / Rangifer tarandus / Caribou* 
1973-1988 - Caribou - Aerial Late Winter Recruitment - Itcha-Ilgachuz, Rainbows     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
1974-1977 - Caribou - Population Review-Expert Knowledge - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
1978-1984 - Caribou - Aerial Post-Calving Population Count & Recruitment - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2022 - Caribou - Aerial Late Winter Recruitment - Itcha-Ilgachuz     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
2023 - Caribou - Aerial Late Winter Recruitment - Itcha-Ilgachuz, Rainbows     Relative Abundance     M-RATA / Rangifer tarandus / Caribou* 
2023 - Caribou - Aerial Post-Calving Population Count & Recruitment - Itcha-Ilgachuz     Absolute Abundance     M-RATA / Rangifer tarandus / Caribou* 
2021 - Caribou - Aerial Post-Calving Population Count & Recruitment - Itcha-Ilgachuz         M-RATA / Rangifer tarandus / Caribou* 
DocumentsHelp (14 records) Display All
Report Publish Year Description Filename
Summary of the 1995 Post Calving and Rut Surveys and the 1996 Late Winter Survey for the Itcha, Ilgachuz and Rainbow Mountains, Cariboo Region  1997  The Itcha, Ilgachuz, and Rainbow Mountains caribou population was surveyed aerially three times in an effort to determine population trends, sex ratio, and calf recruitment. The post calving survey completed on June 21 and 22 observed a total of 1466 caribou; 681 cows, 450 calves, 229 bulls, 71 yearling cows and 35 yearling bulls. The observed calf/100 cow ratio was 70/100 in the Itcha-Ilgachuz herd and 31/100 in the Rainbow herd. Yearlings/100 cows were observed at 16/100. Cows with calves were found at higher elevations than cows without calves, with yearling and adult bulls being found at the lowest elevations. The October rut survey on October 18 and 19 observed 438 caribou; 279 cows, 80 calves, 30 medium bulls and 49 mature bulls. The observed calf/100 cow and bull/100 cow ratio in the Itcha-Ilgachuz herd were 40/100 and 23/100, respectively. In the Rainbow herd the observed calf/100 cow ratio was 13/100 and the bull/100 cow ratio was 36/100. The March late winter survey observed 314 caribou; 172 in forest and 142 in alpine habitat. The Itcha-Ilgachuz herd calf percentage was estimated at 21% and the Rainbow calf percentage was assumed to be 11%. The bull/cow and mature bull/medium bull ratios in the Rainbow herd were higher than the Itcha-Ilgachuz herd. The Itcha-Ilgachuz herd appears to be stable, with an adequate calf recruitment but a low bull to cow ratio. Further studies coupled with population modeling will be necessary to confidently produce a long-term caribou strategy as required by the CCLUP (Cariboo-Chilcotin Land Use Plan).  wsi_5955_rpt_1995-1996.pdf (899 KB)
Summary of the 1996 Post Calving and Rut Surveys and the 1997 Late Winter Survey for the Itcha, Ilgachuz and Rainbow Mountains, Cariboo Region  1998  The Itcha, Ilgachuz, and Rainbow Mountains caribou population was surveyed aerially three times in an effort to determine population trends, sex ratio, and calf recruitment. The post calving survey completed on June 27 and 28 observed a total of 1400 caribou; 648 cows, 358 calves, 204 bulls, 71 yearling cows, 100 yearling bulls and 19 unsexed yearlings. The observed calf/100 cow ratio was 55/100 in the Itcha-Ilgachuz herd and 57/100 in the Rainbow herd. Cows with calves were found at higher elevations than cows without calves, with yearling and adult bulls being found at the lowest elevations. The October rut survey on October 29 and 30 observed 819 caribou; 585 cows, 135 calves, 61 medium bulls and 38 mature bulls. The observed calf/100 cow and bull/100 cow ratios in the Itcha-Ilgachuz herd were 26/100 and 16/100, respectively. In the Rainbow herd the observed calf/100 cow ratio was 9/100 and the bull/100 cow ratio was 24/100. The April late winter survey observed 288 caribou; 244 in forest and 44 in alpine habitat. The Itcha-Ilgachuz herd calf percentage was estimated at 17% and the Rainbow calf percentage was assumed to be 3%. The bull/cow and mature bull/medium bull ratios in the Rainbow herd were higher than the Itcha-Ilgachuz herd. The Itcha-Ilgachuz herd appears to be stable, with an adequate calf recruitment but a low bull to cow ratio. Further studies coupled with population modeling will be necessary to confidently produce a long-term caribou strategy as required by the CCLUP (Cariboo-Chilcotin Land Use Plan).  wsi_5955_rpt_1996-1997.pdf (2.2 MB)
Summary of the 1997 Post Calving and Rut Surveys and the 1998 Late Winter Survey for the Itcha, Ilgachuz and Rainbow Mountains  1998  As part of ongoing monitoring, the Itcha, Ilgachuz, and Rainbow Mountains caribou population was surveyed aerially three times in an effort to determine population trends, sex ratio, and calf recruitment. The post calving survey completed on June 20 and July 3 observed a total of 1800 caribou; 840 cows, 460 calves, 233 bulls, 84 yearling cows, 83 yearling bulls and 100 unsexed animals. The observed calf/100 cow ratio was 56/100 in the Itcha-Ilgachuz herd and 35/100 in the Rainbow herd. Cows with calves were found at higher elevations than cows without calves, with yearling and adult bulls being found at the lowest elevations. The October rut survey on October 20 and 21 observed 726 caribou; 448 cows, 87 calves, 75 mature bulls and 61 immature bulls. The observed calf/100 cow and bull/100 cow ratios in the Itcha-Ilgachuz herd were 23/100 and 31/100, respectively. In the Rainbow herd the observed calf/100 cow ratio was 4/100 and the bull/100 cow ratio was 27/100. The April late winter survey on March 27 and 28 observed 677 caribou; 674 in forest and 3 in alpine habitat. The Itcha-Ilgachuz herd calf percentage was estimated at 13.4% and the Rainbow calf percentage was assumed to be 7%. The Itcha-Ilgachuz herd appears to be stable, with an adequate calf recruitment but a low bull to cow ratio. The Rainbow Mountains herd showed low calf recruitment numbers but bull to cow ratios were higher than those found within the Itcha-Ilgachuz herd. Further studies coupled with population modelling will be necessary to confidently produce a long-term caribou strategy as required by the CCLUP (Cariboo-Chilcotin Land Use Plan).  wsi_5955_rpt_1997-1998.pdf (4.7 MB)
Summary of the 1998 Post Calving and Rut Surveys and the 1999 Late Winter Survey for the Itcha, Ilgachuz and Rainbow Mountains  1999  As part of ongoing monitoring, the Itcha, Ilgachuz, and Rainbow Mountains caribou population was surveyed aerially three times in an effort to determine population trends, sex ratios, and calf recruitment. The post calving survey completed on June 20 and June 21, 1998 observed a total of 2219 caribou; 1060 cows, 578 calves, 349 bulls, 4 yearling cows, 35 yearling bulls and 193 unsexed animals. The observed percent calves was 26.3 in the Itcha-Ilgachuz Herd and 21.4 in the Rainbow Herd. No significant differences in elevation use were found from one age/sex group to the next. The 1998 October rut survey on October 19 and 20 observed 749 caribou; 495 cows, 123 calves, 68 mature bulls and 63 immature bulls. The observed calves/100 cows and bulls/100 cows in the Itcha-Ilgachuz Herd were both 26/100. In the Rainbow Herd the observed calf/100 cow ratio was 18/100 and the bull/100 cow ratio was 27/100. The late winter survey on March 16 and 17 observed 309 caribou, all of which were in forest habitats. The Itcha-Ilgachuz Herd calf percentage was estimated at 14.6% and the Rainbow calf percentage was assumed to be 9%. The Itcha-Ilgachuz Herd appears to be increasing, with adequate calf recruitment and an increasing bull to cow ratio. The Rainbow Mountains Herd showed lower calf recruitment numbers but a more adequate bull to cow ratio. Further studies coupled with population modelling will be necessary to confidently produce a long-term caribou strategy as required by the CCLUP (Cariboo-Chilcotin Land Use Plan).  wsi_5955_rpt_1998-1999.pdf (2.3 MB)
Summary of the 1999 Post Calving and Rut Surveys and the 2000 Late Winter Survey for the Itcha, Ilgachuz and Rainbow Mountains  2001  As part of ongoing monitoring, the Itcha-Ilgachuz and Rainbow Mountains caribou population was surveyed aerially three times in an effort to determine population trends, sex ratios, and calf recruitment. The post calving survey completed on July 13, 14 and 21, 1999 observed a total of 1850 caribou; 936 cows, 404 calves, 294 bulls, 19 yearling cows, 26 yearling bulls and 171 unsexed animals. The observed percent calves was 21.9 in the Itcha-Ilgachuz Herd and 19.8 in the Rainbow Herd. No significant differences in elevation use were found among adult cows, cows with calves or yearlings; however, adult bulls and unclassified adults were both significantly different from all the age/sex groups. The 1999 October rut survey on October 19 and 20 observed 1038 caribou; 658 cows, 193 calves, 94 mature bulls, 90 immature bulls and 3 unclassified. The observed calves/100 cows and bulls/100 cows in the Itcha-Ilgachuz Herd were 29/100 and 26/100, respectively. In the Rainbow Herd the observed calf/100 cow ratio was 29/100 and the bull/100 cow ratio was 43/100. The late winter survey on April 11 observed 452 caribou, all of which were in forest habitats. The Itcha-Ilgachuz Herd calf percentage was estimated at 15.8% and the Rainbow calf percentage was assumed to be 13.0%. The Itcha-Ilgachuz Herd appears to be stable to increasing, with adequate calf recruitment and an increasing bull to cow ratio: the estimated population is 1900-2000 caribou with a density of 0.19 caribou/km2. The Rainbow Mountains Herd showed greater calf recruitment numbers and a relatively high bull to cow ratio compared to recent years: the estimated population was 125 animals at a density of 0.028 caribou/km2. Further studies coupled with population modelling will be necessary to confidently produce a long-term caribou strategy as required by the Cariboo-Chilcotin Land Use Plan (CCLUP).  wsi_5955_rpt_1999-2000.pdf (4.1 MB)
Summary of the 2000 Post Calving and Rut Surveys and the 2001 Late Winter Survey for the Itcha, Ilgachuz and Rainbow Mountains  2001  As part of ongoing monitoring, the Itcha-Ilgachuz and Rainbow Mountains caribou herds were surveyed aerially three times in an effort to determine population trends, sex ratios, and calf recruitment. The post calving survey completed on June 20, 21 and 22, 2000 observed a total of 2224 caribou; 1139 cows, 692 calves, 272 bulls, 38 yearling cows, 59 yearling bulls; 12 unsexed adults and 12 unsexed yearlings. The observed percent calves was 31.1% in the Itcha-Ilgachuz Herd and 33.3% in the Rainbow Herd. No significant differences in elevation use were observed among adult cows, cows with calves, yearling cows or unsexed yearlings. There were also no significant differences among adult bulls, yearling bulls and unclassified adults; however elevation use by the male caribou groups was significantly different from that used by the female caribou groups. The 2000 rut survey on October 31 and November 1 observed 731 caribou; 398 cows, 130 calves, 52 mature bulls, 68 immature bulls and 83 unclassified caribou. The observed calves/100 cows and bulls/100 cows in the Itcha-Ilgachuz Herd were 33/100 and 32/100, respectively. In the Rainbow Herd the observed calf/100 cow ratio was 31/100 and the bull/100 cow ratio was 23/100. The late winter survey on March 15 observed 529 caribou, all of which were in forest habitats. The Itcha-Ilgachuz Herd calf percentage was estimated at 15.3% and the Rainbow calf percentage was estimated at 16.7%. The Itcha- Ilgachuz Herd appears to be stable to increasing, with adequate calf recruitment and an increasing bull to cow ratio: the estimated population is 2000 caribou with a density of 0.20 caribou/km2. The Rainbow Mountains Herd showed greater calf recruitment numbers and a relatively high bull to cow ratio compared to recent years: the estimated population was 125 animals at a density of 0.028 caribou/km2. Further studies coupled with population modelling will be necessary.  wsi_5955_rpt_2000-2001.pdf (4.3 MB)
Field Data Publish Year Description Filename
    Point data for the 1995-2001 Aerial Rut Population Count & Composition survey formatted for entry into SPI  wsi_5955_dct_1995-2001.xlsm (252 KB)
Map Publish Year Description Filename
Rut Census Map 1995  1995  1995 - Itcha Ilgachuz-Rainbows - Rut Census Map  wsi_5955_rpt_1995RutMap.pdf (40.7 MB)
Caribou Survey Flightlines for Itcha Ilgachuz, October 1996  1996  1996 - Itcha Ilgachuz-Rainbows - Rut Census Map  wsi_5955_rpt_1996RutCensusMap.pdf (31.5 MB)
Caribou Survey Flightlines for Itcha Ilgachuz, October 1997  1997  1997 - Itcha Ilgachuz-Rainbows - Rut Census Map  wsi_5955_rpt_1997RutCensusMap.pdf (31.3 MB)
Western Caribou Flight Post-Rut Survey, October 1998  1998  1998 - Itcha Ilgachuz-Rainbows-Charlotte Alplands - Rut Census Map  wsi_5955_rpt_1998RutCensusMap.pdf (37.3 MB)
October 1999 - Rut Survey Rainbows and Itcha Ilgachuz  1999  1999 - Itcha Ilgachuz-Rainbows - Rut Census Map  wsi_5955_rpt_1999RutCensusMap.pdfSecure
October 2000 - Rut Survey Rainbows and Itcha Ilgachuz  2000  2000 - Itcha Ilgachuz-Rainbows - Rut Census Map  wsi_5955_rpt_2000RutCensusMap.pdfSecure
October 2001 - Rut Survey Rainbows and Itcha Ilgachuz  2001  2001 - Itcha Ilgachuz-Rainbows - Rut Census Map  wsi_5955_rpt_2001RutCensusMap.pdfSecure
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