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Remote sensing reveals long-term effects of caribou on tundra vegetation

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Abstract

Declining use and abandonment of traditional ranges by migratory caribou (Rangifer tarandus) have often been related to density-dependent depletion of summer forage. The Pen Islands caribou herd (R. t. caribou), Ontario and Manitoba, Canada, numbered in the thousands on its traditional summer tundra range during the 1980s, but then declined in that region. We postulated that increased caribou abundance over three decades negatively affected phytomass, given that under the exploitation ecosystem hypothesis (EEH), grazers limit the amount of primary production if few predators are present. We tested this prediction using the Normalized Difference Vegetation Index (NDVI), as a proxy for phytomass available to caribou. We lagged caribou abundance in the explanatory model by the number of years (4–7) between peak caribou abundance and minimum NDVI. NDVI was negatively related to caribou abundance lagged by 6 years, and growing degree days explained much of the annual variation in NDVI. Precipitation was not an important predictor in the model. Our study is the first to apply NDVI to support the EEH for caribou. We propose that this method could be used over broad scales to shed light on limiting factors for migratory caribou across the circumpolar North.

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References

  • Abraham KF, Keddy CJ (2005) The Hudson Bay Lowland. In: Kelly PA, Fraser LH (eds) The world’s largest wetlands, 1st edn. Cambridge University Press, New York, pp 118–148

    Google Scholar 

  • Abraham KF, Pond BA, Tully SM, Trim V, Hedman D, Chenier C, Racey GD (2012) Recent changes in summer distribution and numbers of migratory caribou on the southern Hudson Bay Coast. Rangifer 32:269–276

    Google Scholar 

  • Agriculture and Agri-Food Canada (2012) National ecological framework for Canada. http://sis.agr.gc.ca/cansis/nsdb/ecostrat/index.html

  • Archer ERM (2004) Beyond the “climate versus grazing” impasse: using remote sensing to investigate the effects of grazing system choice on vegetation cover in the eastern Karoo. J Arid Environ 57:381–408

    Google Scholar 

  • Arseneault D, Villeneuve N, Boismenu C, Leblanc Y, Deshaye J (1997) Estimating lichen biomass and caribou grazing on the wintering grounds of Northern Quebec: an application of fire history and Landsat data. J Appl Ecol 34:65–78

    Google Scholar 

  • Augustine DJ, McNaughton SJ (1998) Ungulate effects on the functional species composition of plant communities: herbivore selectivity and plant tolerance. J Wildl Manag 62:1165–1183

    Google Scholar 

  • Avgar T, Mosser A, Brown GS, Fryxell JM (2013) Environmental and individual drivers of animal movement patterns across a wide geographical gradient. J Anim Ecol 82:96–106

    PubMed  Google Scholar 

  • Ballenberghe VV (1985) Wolf predation on caribou: the Nelchina Herd case history. J Wildl Manag 49:711–720

    Google Scholar 

  • Bergerud AT (1977) Diets for caribou. In: Recheigl Jr. J (ed) CRC Handbook series in nutrition and food. Section G: diets, culture, media, and food supplements, vol 1. Diets for mammals. CRC Press, Cleveland, pp 243–266

  • Bergerud AT (1980) A review of the population dynamics of caribou and wild reindeer in North America. In: Reimers, E, Gaare, E, Skjenneberg, S (eds) Proceedings of the 2nd international reindeer/caribou symposium held on 17–21 September 1979 in Røros, Norway. Direktoratet for vilt og ferskvannsfisk, Trondheim, Norway, pp 556–581

  • Bergerud AT (1996) Evolving perspectives on caribou population dynamics, have we got it right yet? Rangifer 16:95–115

    Google Scholar 

  • Bergerud AT, Ballard WB (1988) Wolf predation on caribou: the Nelchina herd case history, a different interpretation. J Wildl Manag 52:344–357

    Google Scholar 

  • Bergerud AT, Nolan MJ, Curnew K, Mercer WE (1983) Growth of the Avalon Peninsula, Newfoundland caribou herd. J Wildl Manag 47:989–998

    Google Scholar 

  • Bergerud AT, Luttich SN, Camps L (2008) The return of caribou to Ungava. McGill-Queen’s University Press, Montréal

    Google Scholar 

  • Blanco LJ, Aguilera MO, Paruelo JM, Biurrun FN (2008) Grazing effect on NDVI across an aridity gradient in Argentina. J Arid Environ 72:764–776

    Google Scholar 

  • Blanco LJ, Ferrando CA, Biurrun FN (2009) Remote sensing of spatial and temporal vegetation patterns in two grazing systems. Rangel Ecol Manag 62:445–451

    Google Scholar 

  • Boone RB, Thirgood SJ, Hopcraft JG (2006) Serengeti Wildebeest migratory patterns modeled from rainfall and new vegetation growth. Ecology 87:1987–1994

    PubMed  Google Scholar 

  • Boudreau S, Payette S (2004) Caribou-induced changes in species dominance of lichen woodlands: an analysis of plant remains. Am J Bot 91:422–429

    PubMed  Google Scholar 

  • Bradley BA, O’Sullivan MT (2011) Assessing the short-term impacts of changing grazing regime at the landscape scale with remote sensing. Int J Remote Sens 32:5797–5813

    Google Scholar 

  • Bro-Jørgensen J, Brown M, Pettorelli N (2008) Using the satellite-derived normalized difference vegetation index (NDVI) to explain ranging patterns in a lek-breeding antelope: the importance of scale. Oecologia 158:177–182

    PubMed  Google Scholar 

  • Burnham KP, Anderson DR (2002) Model selection and multimodel inference: a practical information-theoretic approach. Springer, New York

    Google Scholar 

  • Canty MJ, Nielsen AA (2008) Automatic radiometric normalization of multitemporal satellite imagery with the iteratively re-weighted MAD transformation. Remote Sens Environ 112:1025–1036

    Google Scholar 

  • Chander G, Markham BL, Helder DL (2009) Summary of current radiometric calibration coefficients for Landsat MSS, TM, ETM+, and EO-1 ALI sensors. Remote Sens Environ 113:893–903

    Google Scholar 

  • Chen W, Chen W, Li J, Zhang Y, Fraser R, Olthof I, Leblanc SG, Chen Z (2012) Mapping aboveground and foliage biomass over the Porcupine caribou habitat in northern Yukon and Alaska using Landsat and JERS-1/SAR data. In: Fatoyinbo T (ed) Remote sensing of biomass - Principles and applications. InTech, pp 231–252

  • Core Team R (2012) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna

    Google Scholar 

  • Couturier S, Brunelle J, Vandal D, St-Martin G (1990) Changes in the population dynamics of the George River caribou herd, 1976–87. Arctic 43:9–20

    Google Scholar 

  • Couturier S, Côté SD, Otto RD, Weladji RB, Huot J (2009) Variation in calf body mass in migratory caribou: the role of habitat, climate, and movements. J Mammal 90:442–452

    Google Scholar 

  • Crête M, Doucet GJ (1998) Persistent suppression in dwarf birch after release from heavy summer browsing by caribou. Arct Alp Res 30:126–132

    Google Scholar 

  • Crête M, Huot J (1993) Regulation of a large herd of migratory caribou: summer nutrition affects calf growth and body reserves of dams. Can J Zool 71:2291–2296

    Google Scholar 

  • Crête M, Huot J, Gauthier L (1990) Food selection during early lactation by caribou calving on the tundra in Quebec. Arctic 43:60–65

    Google Scholar 

  • Crête M, Ouellet J, Lesage L (2001) Comparative effects on plants of caribou/reindeer, moose and white-tailed deer herbivory. Arctic 54:407–417

    Google Scholar 

  • Den Herder M, Virtanen R, Roininen H (2004) Effects of reindeer browsing on tundra willow and its associated insect herbivores. J Appl Ecol 41:870–879

    Google Scholar 

  • Eskelinen A, Oksanen J (2006) Changes in the abundance, composition and species richness of mountain vegetation in relation to summer grazing by reindeer. J Veg Sci 17:245–254

    Google Scholar 

  • ESRI (2010) ArcGIS version 10.1. Environmental Systems Research Institute, Redlands

    Google Scholar 

  • Frazier PS, Page KJ (2000) Water body detection and delineation with Landsat TM data. Photogramm Eng Remote Sens 66:1461–1467

    Google Scholar 

  • Fretwell SD (1977) The regulation of plant communities by food chains exploiting them. Perspect Biol Med 20:169–185

    Google Scholar 

  • Griller N (2001) Short and long term recovery of plant communities following intensive grazing by caribou (Rangifer tarandus) and muskoxen (Ovibos moschatus) in the low arctic of Nunavut, Canada. PhD thesis, The University of British Columbia, Vancouver, British Columbia

  • Grippa M, Kergoat L, Le Toan T, Mognard NM, Delbart N, L’Hermitte J, Vicente-Serrano S (2005) The impact of snow depth and snowmelt on the vegetation variability over central Siberia. Geophys Res Lett 32:L21412

    Google Scholar 

  • Grueber CE, Nakagawa S, Laws RJ, Jamieson IG (2011) Multimodel inference in ecology and evolution: challenges and solutions. J Evol Biol 24:699–711

    PubMed  CAS  Google Scholar 

  • Hamel S, Garel M, Festa-Bianchet M, Gaillard J, Côté SD (2009) Spring Normalized Difference Vegetation Index (NDVI) predicts annual variation in timing of peak faecal crude protein in mountain ungulates. J Appl Ecol 46:582–589

    Google Scholar 

  • Hansen BU (1991) Monitoring natural vegetation in southern Greenland using NOAA AVHRR and field measurements. Arctic 44:94–101

    Google Scholar 

  • Hansen BB, Henriksen S, Aanes R, Sæther B (2007) Ungulate impact on vegetation in a two-level trophic system. Polar Biol 30:549–558

    Google Scholar 

  • Hassan QK, Bourque CP, Meng FR, Richards W (2007) Spatial mapping of growing degree days: an application of MODIS-based surface temperatures and enhanced vegetation index. J Appl Remote Sens 1:013511

    Google Scholar 

  • Heard DC, Williams MT, Melton DA (1996) The relationship between food intake and predation risk in migratory caribou and implications to caribou and wolf population dynamics. Rangifer 16:37–44

    Google Scholar 

  • Hebblewhite M, Merrill EH (2009) Trade-offs between predation risk and forage differ between migrant strategies in a migratory ungulate. Ecology 90:3445–3454

    PubMed  Google Scholar 

  • Henry GHR, Gunn A (1991) Recovery of tundra vegetation after overgrazing by caribou in Arctic Canada. Arctic 44:38–42

    Google Scholar 

  • Hilker T, Natsagdorj E, Waring RH, Lyapustin A, Wang Y (2014) Satellite observed widespread decline in Mongolian grasslands largely due to overgrazing. Glob Change Biol 20:418–428

    Google Scholar 

  • Holdo RM, Holt RD, Fryxell JM (2009) Opposing rainfall and plant nutritional gradients best explain the wildebeest migration in the Serengeti. Am Nat 173:431–445

    PubMed  Google Scholar 

  • Honaker J, King G (2010) What to do about missing values in time-series cross-section data. Am J Polit Sci 54:561–581

    Google Scholar 

  • Honaker J, King G, Blackwell M (2011) AMELIA II: a program for missing data. http://j.mp/k4t8Ej. Accessed 27 Jan 2014

  • Huete A, Didan K, Miura T, Rodriguez EP, Gao XLGF (2002) Overview of the radiometric and biophysical performance of the MODIS vegetation indices. Remote Sens Environ 83:195–213

    Google Scholar 

  • Ito TY, Miura N, Lhagvasuren B, Enkhbileg D, Takatsuki S, Tsunekawa A, Jiang Z (2006) Satellite tracking of Mongolian gazelles (Procapra gutturosa) and habitat shifts in their seasonal ranges. J Zool 269:291–298

    Google Scholar 

  • Jano AP, Jefferies RL, Rockwell RF (1998) The detection of vegetational change by multitemporal analysis of LANDSAT Data: the effects of goose foraging. J Ecol 86:93–99

    Google Scholar 

  • Jefferies RL, Jano AP, Abraham KF (2006) A biotic agent promotes large-scale catastrophic change in the coastal marshes of Hudson Bay. J Ecol 94:234–242

    Google Scholar 

  • Jenkins JP, Braswell BH, Frolking SE, Aber JD (2002) Detecting and predicting spatial and interannual patterns of temperate forest springtime phenology in the eastern US. Geophys Res Lett 29:2201

    Google Scholar 

  • Ji P, Peters AJ (2005) Lag and seasonality considerations in evaluating AVHRR NDVI response to precipitation. Photogramm Eng Remote Sens 71:1053–1061

    Google Scholar 

  • Joly K, Stuart Chapin F, Klein DR (2010) Winter habitat selection by caribou in relation to lichen abundance, wildfires, grazing, and landscape characteristics in northwest Alaska. Ecoscience 17:321–333

    Google Scholar 

  • Karabulut M (2003) An examination of relationships between vegetation and rainfall using maximum value composite AVHRR-NDVI data. Turk J Bot 27:93–101

    Google Scholar 

  • Kayhko J, Pellikka P (1994) Remote sensing of the impact of reindeer grazing on vegetation in northern Fennoscandia using SPOT XS data. Polar Res 13:115–124

    Google Scholar 

  • Kershaw KA, Rouse WR (1973) Studies on lichen-dominated systems. V. A primary survey of a raised-beach system in northwestern Ontario. Can J Bot 51:1285–1307

    Google Scholar 

  • Kumpula J, Colpaert A, Nieminen M (2000) Condition, potential recovery rate, and productivity of lichen (Cladonia spp.) ranges in the Finnish reindeer management area. Arctic 53:152–160

    Google Scholar 

  • Kumpula J, Stark S, Holand à (2011) Seasonal grazing effects by semi-domesticated reindeer on subarctic mountain birch forests. Polar Biol 34:441–453

    Google Scholar 

  • Laidler GJ, Treitz P (2003) Biophysical remote sensing of arctic environments. Prog Phys Geogr 27:44–68

    Google Scholar 

  • Leader-Williams N (1980) Population dynamics and mortality of reindeer introduced into South Georgia. J Wildl Manag 44:640–657

    Google Scholar 

  • Leader-Williams N, Smith RIL, Rothery P (1987) Influence of introduced reindeer on the vegetation of South Georgia: results from a long-term exclusion experiment. J Appl Ecol 24:801–822

    Google Scholar 

  • Lind M, Rasmussen K, Adriansen H, Ka A (2003) Estimating vegetative productivity gradients around watering points in the rangelands of Northern Senegal based on NOAA AVHRR data. Geogr TIDSSKR 103:1–15

    Google Scholar 

  • Magoun AJ, Abraham KF, Thompson JE, Ray JC, Gauthier ME, Brown GS, Woolmer G, Chenier CJ, Dawson FN (2005) Distribution and relative abundance of caribou in the Hudson Plains Ecozone of Ontario. Rangifer 25:105–121

    Google Scholar 

  • Mahoney SP, Schaefer JA (2002) Long-term changes in demography and migration of Newfoundland caribou. J Mammal 83:957–963

    Google Scholar 

  • Manseau M, Huot J, Crête M (1996) Effects of summer grazing by caribou on composition and productivity of vegetation: community and landscape level. J Ecol 84:503–513

    Google Scholar 

  • Martinuzzi S, Gould WA, Ramos González OM (2006) Creating cloud-free Landsat ETM+ data sets in tropical landscapes: cloud and cloud-shadow removal. U.S. Department of Agriculture, Forest Service, International Institute of Tropical Forestry, Rio Piedras

    Google Scholar 

  • Mazerolle MJ (2013) AICcmodavg: model selection and multimodel inference based on (Q)AIC(c). R package version 1.35. http://cran.r-project.org/web/packages/AICcmodavg/index.html. Accessed 12 Jan 2014

  • McKenney DW, Pedlar JH, Papadopol P, Hutchinson MF (2006) The development of 1901–2000 historical monthly climate models for Canada and the United States. Agric For Meteorol 138:69–81

    Google Scholar 

  • McNaughton SJ (1984) Grazing lawns: animals in herds, plant form, and coevolution. Am Nat 124:863–886

    Google Scholar 

  • Messier F, Huot J, Le Hénaff D, Luttich SN (1988) Demography of the George River caribou herd: evidence of population regulation by forage exploitation and range expansion. Arctic 41:279–287

    Google Scholar 

  • Mueller T, Olson KA, Fuller TK, Schaller GB, Murray MG, Leimgruber P (2008) In search of forage: predicting dynamic habitats of Mongolian gazelles using satellite-based estimates of vegetation productivity. J Appl Ecol 45:649–658

    Google Scholar 

  • Nakagawa S, Freckleton RP (2011) Model averaging, missing data and multiple imputation: a case study for behavioural ecology. Behav Ecol Sociobiol 65:103–116

    Google Scholar 

  • Neigh CSR, Tucker CJ, Townshend JRG (2008) North American vegetation dynamics observed with multi-resolution satellite data. Remote Sens Environ 112:1749–1772

    Google Scholar 

  • Newton EJ (2012) Factors affecting changes in the distribution and abundance of migratory caribou (Rangifer tarandus) in the Hudson Bay Lowlands. MSc thesis, Trent University, Peterborough, Ontario

  • Nielsen AA (2007) The regularized iteratively reweighted MAD method for change detection in multi- and hyperspectral data. IEEE Trans Image Process 16:463–478

    PubMed  Google Scholar 

  • Oksanen L (1983) Trophic exploitation and arctic phytomass patterns. Am Nat 122:45–52

    Google Scholar 

  • Oksanen L, Fretwell SD, Arruda J, Niemela P (1981) Exploitation ecosystems in gradients of primary productivity. Am Nat 118:240–261

    Google Scholar 

  • Olofsson J (2006) Short-and long-term effects of changes in reindeer grazing pressure on tundra heath vegetation. J Ecol 94:431–440

    Google Scholar 

  • Olofsson J, Tømmervik H, Callaghan TV (2012) Vole and lemming activity observed from space. Nat Clim Change 2:880–883

    Google Scholar 

  • Olthof I, Pouliot D, Latifovic R, Chen W (2008) Recent (1986–2006) vegetation-specific NDVI trends in northern Canada from satellite data. Arctic 61:381–394

    Google Scholar 

  • Ouellet J-P, Heard DC, Boutin S (1993) Range impacts following the introduction of caribou on Southampton Island, Northwest Territories, Canada. Arct Alp Res 25:136–141

    Google Scholar 

  • Pajunen A, Virtanen R, Roininen H (2008) The effects of reindeer grazing on the composition and species richness of vegetation in forest-tundra ecotone. Polar Biol 31:1233–1244

    Google Scholar 

  • Pettorelli N, Vik JO, Mysterud A, Gaillard J, Tucker CJ, Stenseth NC (2005a) Using the satellite-derived NDVI to assess ecological responses to environmental change. Trends Ecol Evol 20:503–510

    PubMed  Google Scholar 

  • Pettorelli N, Weladji RB, Holand Ø, Mysterud A, Breie H, Stenseth NC (2005b) The relative role of winter and spring conditions: linking climate and landscape-scale plant phenology to alpine reindeer body mass. Biol Lett 1:24–26

    PubMed Central  PubMed  Google Scholar 

  • Pickup G, Chewings VH (1994) A grazing gradient approach to land degradation assessment in arid areas from remotely-sensed data. Int J Remote Sens 15:597–617

    Google Scholar 

  • Post E, Pedersen C (2008) Opposing plant community responses to warming with and without herbivores. Proc Natl Acad Sci 105:12353–12358

    PubMed Central  PubMed  CAS  Google Scholar 

  • Pouliot D, Latifovic R, Olthof I (2009) Trends in vegetation NDVI from 1 km AVHRR data over Canada for the period 1985–2006. Int J Remote Sens 30:149–168

    Google Scholar 

  • Raynolds MK, Walker DA, Epstein HE, Pinzon JE, Tucker CJ (2012) A new estimate of tundra-biome phytomass from trans-Arctic field data and AVHRR NDVI. Remote Sens Lett 3:403–411

    Google Scholar 

  • Riley JL (2011) Wetlands of the Ontario Hudson Bay lowland: a regional overview. Nature Conservancy of Canada, Toronto

    Google Scholar 

  • Rouse WR, Kershaw KA (1973) Studies on lichen-dominated systems. VI. Interrelations of vegetation and soil moisture in the Hudson Bay Lowlands. Can J Bot 51:1309–1316

    Google Scholar 

  • Rubin DB (1987) Multiple imputation for nonresponse in surveys. Wiley, New York

    Google Scholar 

  • Russell DE, Martell AM, Nixon WAC (1993) Range ecology of the Porcupine caribou herd in Canada. Rangifer 13:1–168

    Google Scholar 

  • Ryan SJ, Cross PC, Winnie J, Hay C, Bowers J, Getz WM (2012) The utility of normalized difference vegetation index for predicting African buffalo forage quality. J Wildl Manag 76:1499–1508

    Google Scholar 

  • Schafer JL (1997) Analysis of incomplete multivariate data. Chapman & Hall, London

    Google Scholar 

  • Smallidge ST, Baker TT, VanLeeuwen D, Gould WR, Thompson BC (2010) Elk distributions relative to spring Normalized Difference Vegetation Index values. Int J Ecol 2010:1–10

    Google Scholar 

  • Sonnenschein R, Kuemmerle T, Udelhoven T, Stellmes M, Hostert P (2011) Differences in Landsat-based trend analyses in drylands due to the choice of vegetation estimate. Remote Sens Environ 115:1408–1420

    Google Scholar 

  • Tanentzap AJ, Coomes DA (2012) Carbon storage in terrestrial ecosystems: do browsing and grazing in herbivores matter? Biol Rev 87:72–94

    PubMed  Google Scholar 

  • Théau J, Duguay CR (2004) Lichen mapping in the summer range of the George River caribou herd using Landsat TM imagery. Can J Remote Sens 30:867–881

    Google Scholar 

  • Théau J, Peddle DR, Duguay CR (2005) Mapping lichen in a caribou habitat of Northern Quebec, Canada, using an enhancement classification method and spectral mixture analysis. Remote Sens Environ 94:232–243

    Google Scholar 

  • Thomas DL, Johnson D, Griffith B (2006) A Bayesian random effects discrete-choice model for resource selection: population-level selection inference. J Wildl Manag 70:404–412

    Google Scholar 

  • Thompson JE, Abraham KF (1994) Range, seasonal distribution and population dynamics of the Pen Islands Caribou Herd of southern Hudson Bay. Ontario Ministry of Natural Resources Final Technical Report, Moosonee pp 94 

    Google Scholar 

  • Tucker CJ, Pinzon JE, Brown ME, Slayback DA, Pak EW, Mahoney R, Vemote EF, El Saleous N (2005) An extended AVHRR 8-km NDVI dataset compatible with MODIS and SPOT vegetation NDVI data. Int J Remote Sens 26:4485–4498

    Google Scholar 

  • Tveraa T, Fauchald P, Gilles Yoccoz N, Anker Ims R, Aanes R, Arild Høgda K (2007) What regulate and limit reindeer populations in Norway? Oikos 116:706–715

    Google Scholar 

  • Uleberg E, Hanssen-Bauer I, van Oort B, Dalmannsdottir S (2014) Impact of climate change on agriculture in Northern Norway and potential strategies for adaptation. Clim Change 122:27–39

    Google Scholar 

  • USGS (2011) U.S. geological survey. http://www.usgs.gov/. Accessed 2 Feb 2011

  • van der Wal R, Brooker R, Cooper E, Langvatn R (2001) Differential effects of reindeer on high arctic lichens. J Veg Sci 12:705–710

    Google Scholar 

  • Väre H, Ohtonen R, Oksanen J (1995) Effects of reindeer grazing on understorey vegetation in dry Pinus sylvestris forests. J Veg Sci 6:523–530

    Google Scholar 

  • Virtanen R (2000) Effects of grazing on above-ground biomass on a mountain snowbed, NW Finland. Oikos 90:295–300

    Google Scholar 

  • Vors LS, Boyce MS (2009) Global declines of caribou and reindeer. Glob Change Biol 15:2626–2633

    Google Scholar 

  • Wegener C, Odasz-Albrigtsen A (1998) Do Svalbard reindeer regulate standing crop in the absence of predators? A test of the “exploitation ecosystems” model. Oecologia 116:202–206

    Google Scholar 

  • Xie Y, Sha Z, Yu M (2008) Remote sensing imagery in vegetation mapping: a review. Plant Ecol 1:9–23

    Google Scholar 

  • Yang W, Yang L, Merchant JW (1997) An assessment of AVHRR/NDVI-ecoclimatological relations in Nebraska, U.S.A. Int J Remote Sens 18:2161–2180

    Google Scholar 

  • Yu Q, Epstein HE, Walker DA, Frost GV, Forbes BC (2011) Modeling dynamics of tundra plant communities on the Yamal Peninsula, Russia, in response to climate change and grazing pressure. Environ Res Lett 6:045505

    Google Scholar 

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Acknowledgments

Financial support was provided by the Ontario Ministry of Natural Resources (Wildlife Research and Monitoring Section and Far North Branch), a Natural Sciences and Engineering Research Council of Canada (NSERC) grant to JS, and a NSERC Scholarship, Ontario Graduate Scholarship, Northern Scientific Training Program grant, Canadian National Sportsmen’s Shows grant, and David and Joyce Woods Graduate Scholarship to EJN. This work was made possible through data collection carried out by OMNR personnel, pilots, engineers, and volunteers. We thank also those who aided with mapping, statistics, remote sensing and other guidance: Guillaume Bastille-Rousseau, Dennis Duro, Shinichi Nakagawa, Mort Canty, Todd Schroeder, Steven Franklin, Erica Nol, Megan Hornseth, Mike Kyffin, Tracy Armstrong, Jane Devlin, Max DeBues, Kaiti Nixon, and Brad Vandermeulen.

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  1. Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, K9J 7B8, Canada

    Erica J. Newton

  2. Ontario Ministry of Natural Resources, Second Floor DNA Building, Block B, 2140 East Bank Drive, Peterborough, ON, K9J 7B8, Canada

    Erica J. Newton, Bruce A. Pond & Kenneth F. Abraham

  3. Ontario Ministry of Natural Resources, 1235 Queen Street East, Sault Ste. Marie, ON, P6A 2E5, Canada

    Glen S. Brown

  4. Department of Biology, Trent University, Peterborough, ON, K9J 7B8, Canada

    James A. Schaefer

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Correspondence to Erica J. Newton.

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Newton, E.J., Pond, B.A., Brown, G.S. et al. Remote sensing reveals long-term effects of caribou on tundra vegetation. Polar Biol 37, 715–725 (2014). https://doi.org/10.1007/s00300-014-1472-3

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