Impacts of climate-driven habitat change on the peak calving date of the Bathurst caribou in Arctic Canada
Since mid-1980’s, the population of the Bathurst barren ground caribou (Rangifer tarandus) in Canada’s Arctic has declined by 93%. In order to develop and implement an effective recovery plan, it is important to know how various factors have cumulatively impacted the population decline. To contribute to the knowledge, we investigated the following two questions: how have changes in climate-induced habitat conditions impacted the peak calving date of the Bathurst caribou, and what was the implication of the impact on the population? Our results indicate that the peak calving date was impacted by changes in habitat conditions (e.g., the start date of vegetation growing season SOS) in a complex manner. Large inter-annual variations in SOS on the calving ground and summer range of the Bathurst herd were observed during 1985 and 2012, with the largest difference being 29 days. A 1-day delay of SOS in year i − 1 on the calving ground (SOScg(i − 1)) from its normal date could result in a 0.5-day delay in the peak calving date in year i, likely caused by the delay in the conception date in the previous fall. However, advances in SOScg(i − 1) did not alter the peak calving date in year i. Furthermore, a 1-day delay (or advance) in the current year’s SOS on the summer range (SOSsr(i)) might cause a 0.23-day delay (or advance) in the peak calving date in the current year, likely through changing the caribou’s gestation duration. Together SOScg(i − 1) and SOSsr(i) explained 69.1% of the variation in the peak calving date of the Bathurst caribou herd during 1985–2012, indicating the cumulative impacts on the peak calving date by the changing habitat conditions over a period of 2 years and thus the validation of the cumulative habitat impact hypothesis. Finally, our results also show that a 1-day delay in the peak calving date corresponded approximately 2–3% reduction in the birth rate of the Bathurst caribou, and thus might have been partially responsible for the population decline.
KeywordsBathurst caribou Vegetation Phenology Calving date Remote sensing
Roy Judas and Brain Kodzin (Wekweeti), and Claire Elliott and Elyn Humphreys (Carleton University) participated in the community-based vegetation monitoring in 2013 and 2014. Bonnie Fournier and Adrian D’Hont from Environment and Natural Resources of GNWT provided the collared cow GPS data and range map. Rasim Latifovic, Fuqun Zhou, Richard Fernandes, and Ian Olthof of CCRS provided the 10-day AVHRR composites, snow cover, and land cover data. The guidance, suggestions, and technical assistance from Government of NWT, Tlicho Government, Wek’èezhìi Renewable Resources Board, and CircumArctic Rangifer Monitoring and Assessment Network (CARMA) are much appreciated. We are grateful for the comments made by anonymous reviewers, which have significantly strengthened the manuscript.
The study is funded by the NWT Cumulative Impact Monitoring Program (CIMP) of the Government of Northwest Territories and the Remote Sensing Science Program of Natural Resources Canada.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
All applicable international, national, and institutional guidelines for the care and use of animals were followed.
- Bergerud AT, Luttich SN, Camps L (2008) The return of Caribou to Ungava. McGill-Queen’s University Press, MontrealGoogle Scholar
- Chen W, Russell DE, Gunn A, Croft B, Chen WR, Fernandes R, Zhao H, Li J, Zhang Y, Koehler K, Olthof I, Fraser RH, Leblanc SG, Henry GR, White RG, Finstad GL (2013a) Monitoring habitat condition changes during winter and pre-calving migration for Bathurst Caribou in northern Canada. Biodiversity 14:36–44CrossRefGoogle Scholar
- Chen W, Zorn P, Chen Z, Latifovic R, Zhang Y, Li J, Quirouette J, Olthof I, Fraser R, Mclennan D, Poitevin J, Stewart HM, Sharma R (2013b) Propagation of errors associated with scaling foliage biomass from field measurements to remote sensing data over Canada’s northern national park. Remote Sens Environ 130:205–218CrossRefGoogle Scholar
- Chen W, Foy N, Olthof I, Latifovic R, Zhang Y, Li J, Fraser R, Chen Z, McLennan D, Poitevin J, Zorn P, Quirouette J, Stewart HM (2013c) Evaluating and reducing errors in seasonal profiles of AVHRR vegetation indices over a Canadian northern national park using cloudiness index. Int J Remote Sens 34:4320–4343CrossRefGoogle Scholar
- Chen W, White L, Adamczewski JZ, Croft B, Garner K, Pellissey JS, Clark K, Olthof I, Latifovic R, Finstad GL (2014a) Assessing the impacts of summer range on Bathurst caribou’s productivity and abundance since 1985. Nat Resour 5:130–145Google Scholar
- Eloranta E, Nieminen M (1986) Calving of the experimental reindeer herd in Kaamanen during 1970–85 6:115–121Google Scholar
- Espmark Y (1980) Effects of maternal pre-partum undernutrition on early mother-calf relationships in reindeer. In: Reimers E, Gaare E, Skjenneberg S (eds) Proceedings of the second international reindeer/caribou symposium. Røros, Norway, pp 485–496Google Scholar
- Griffith B, Douglas DC, Walsh NE, Young DD, McCabe TR, Russell DE, White RG, Cameron RD, Whitten KR (2002) The Porcupine caribou herd. In: Douglas DC, Reynolds PE, Rhode EB (ed) Arctic Refuge coastal plain terrestrial wildlife research summaries, USGS Biological Science Report 2002-000, pp 8–37Google Scholar
- Gunn A, D’Hont A, Williams J, Boulanger J (2013) Satellite collaring in the Bathurst Herd of Barren-ground Caribou 1996–2005. Environment and Natural Resources Manuscript Report No. 225, YellowknifeGoogle Scholar
- Johnson CJ, Boyce MS, Case RL, Cluff HD, Gau RJ, Gunn A, Mulders R (2005) Cumulative effects of human developments on Arctic wildlife. Wildl Monogr 160:1–36Google Scholar
- Kattsov VM, Källén E (2005) Future climate change: modeling and scenarios for the Arctic. In: Symon C et al (eds) Arctic Climate Impacts Assessment (ACIA). Cambridge University Press, Cambridge, pp 100–150Google Scholar
- Kelleyhouse RA (2001) Calving ground habitat selection: Teshekpuk Lake and western Arctic caribou herds. MS theses, University of Alaska, Fairbanks, p 124Google Scholar
- Klein DR (1989) Subsistence hunting. In: Hudson RJ, Drew KR, Baskin LM (eds) Wildlife production systems: economic utilisation of wild ungulates. Cambridge University Press, Cambridge, pp 96–111Google Scholar
- Klein D, Baskin LM, Bogoslovskaya LS, Danell K, Gunn A, Irons DB, Kofinas GP, Kovacs KM et al (2005) Management and conservation of wildlife in a changing Arctic. In: Symon C, Arris L, Heal B (eds) Arctic climate impact assessment. Cambridge University Press, Cambridge, pp 597–648Google Scholar
- Kumpula T, Forbes B, Stammler F (2006) Combining data from satellite images and reindeer herders in Arctic petroleum development: the case of Yamal, West Siberia. Nordia Geograph Pub 35:17–30Google Scholar
- Latifovic R, Trishchenfo AP, Chen J, Park WB, Kholpenkov KV, Fernandes R, Pouliot D, Ungureanu C, Luo Y, Wang S, Davidson A, Cihlar J (2005) Generating historical AVHRR 1 km baseline satellite data records over Canada suitable for climate change studies. Can J Remote Sens 31:324–346CrossRefGoogle Scholar
- Lutsel K’e Dené First Nation (2005) Ni hat’ni—watching the land: results of 2003–2005 monitoring activities in the traditional territory of the Åutsÿl K’e Denesôåine. Report to the West Kitikmeot Slave Study Society, YellowknifeGoogle Scholar
- Nishi J, Croft B, Williams J, Boulanger J, and Johnson D (2007) An estimate of breeding females in the Bathurst caribou herd of barren ground caribou, June 2006. File report no. 137, Department of Environment and Natural Resources, Government of Northwest TerritoriesGoogle Scholar
- Pedhazur E (1997) Multiple regression in behavioral research: explanation and prediction, 3rd edn. Holt, Rinehart and Winston, OrlandoGoogle Scholar
- Richter-Menge J, Overland J, Proshutinsky A, Romanovsky V, Bengtsson L, Brigham L, Dyurgerov M, Gascard JC, Gerland S, Graversen R, Haas C, Karcher M, Kuhry P, Maslanik J, Melling H, Maslowski W, Morison J, Perovich D, Przybylak R, Rachold V, Rigor I, Shiklomanov A, Stroeve J, Walker D, Walsh J (2006) State of the Arctic. National Oceanic and Atmospheric Administration OAR Special Report, SeattleGoogle Scholar
- Skogland T (1989) Comparative social organization of wild reindeer in relation to food, mates and predator avoidance. Paul Parey, BerlinGoogle Scholar
- Sutherland M, Gunn A (1996) Bathurst calving ground surveys, 1965–1996. Northwest Territories Department of Resources, Wildlife and Economic Development File Report No. 118, YellowknifeGoogle Scholar