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Shrub Encroachment Impacts the Potential for Multiple Use Conflicts on Public Land

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Abstract

Public rangelands in North America are typically managed under a multiple use policy that includes livestock grazing and wildlife management. In this article we report on the landscape level extent of grassland loss to shrub encroachment in a portion of the Rocky Mountain Forest Reserve in southwestern Alberta, Canada, and review the associated implications for simultaneously supporting livestock and wildlife populations while maintaining range health on this diminishing vegetation type. Digitized aerial photographs of 12 km of valley bottom from 1958 and 1974 were co-registered to ortho-rectified digital imagery taken in 1998, and an un-supervised classification used to determine areas associated with grassland and shrubland in each year. Field data from 2002 were over-layed using GPS coordinates to refine the classification using a calibration-validation procedure. Over the 40-year study period, open grasslands declined from 1,111 ha in 1958 to 465 ha in 1998, representing a 58% decrease. Using mean production data for grass and shrub dominated areas we then quantified aggregate changes in grazing capacity of both primary (grassland) and secondary (shrubland) habitats for livestock and wildlife. Total declines in grazing capacity from 1958 to 1998 totaled 2,744 Animal Unit Months (AUMs) of forage (−39%), including a 58% decrease in primary (i.e., open grassland) range, which was only partly offset by the availability of 1,357 AUMs within less productive and less accessible shrubland habitats. Our results indicate shrub encroachment has been extensive and significantly reduced forage availability to domestic livestock and wildlife, and will increase the difficulty of conserving remaining grasslands. Although current grazing capacities remain marginally above those specified by regulated grazing policies, it is clear that continued habitat change and decreases in forage availability are likely to threaten the condition of remaining grasslands. Unless shrub encroachment is arrested or grassland restoration initiated, reductions in aggregate ungulate numbers may be necessary.

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Notes

  1. Nomenclature follows that of Moss (1983)

References

  • Adams BW, Castelli O, Gardner FG, Cartwright G, Clark J (1992) Fire and grazing to manage willow shrubland on foothill range. Range Notes 15:1–6. Pub. No. T/207. Lands and Forest Services, Edmonton, Alberta, Canada

    Google Scholar 

  • Archer S, Scifres C, Bassham CR, Maggio R (1988) Autogenic succession in a subtropical savanna: conversion of grassland to thorn woodland. Ecological Monographs 58(2):111–127

    Article  Google Scholar 

  • Archer SR, Schimel DS, Holland EH (1995) Mechanisms of shrubland expansion: land use, climate or CO2? Climate Change 29:91–99

    Article  Google Scholar 

  • Bai Y, Broersma K, Thompson D, Ross TJ (2004) Landscape-level dynamics of grassland-forest transitions in British Columbia. Journal of Range Management 57:66–75

    Article  Google Scholar 

  • Bailey AW, Wroe AL (1974) Aspen invasion in a portion of the Alberta parklands. Journal of Range Management 33:37–40

    Article  Google Scholar 

  • Baker WL (1992) Effects of settlement and fire suppression on landscape structure. Ecology 73:1879–1887

    Article  Google Scholar 

  • Bonham CD (1989) Measurements for terrestrial vegetation. Wiley, New York, NY, 338 pp

    Google Scholar 

  • Bork EW, Burkinshaw AM (2009) Cool-season floodplain meadow responses to shrub encroachment in Alberta. Rangeland Ecology and Management 62:44–52

    Article  Google Scholar 

  • Bork E, Smith D, Willoughby M (1996) Prescribed burning of bog birch. Rangelands 18(1):4–7

    Google Scholar 

  • Bork EW, Adams BW, Willms WD (2002) Resilience of foothills rough fescue, Festuca campestris, rangeland to wildfire. Canadian Field Naturalist 116:51–59

    Google Scholar 

  • Bragg TB, Hulbert LC (1976) Woody plant invasion of unburned Kansas bluestem prairie. Journal of Range Management 29:19–24

    Article  Google Scholar 

  • Briggs JM, Hoch JA, Johnson LC (2002a) Assessing the rate, mechanisms, and consequences of the conversion of tallgrass prairie to Juniperus virginiana forest. Ecosystems 5:578–586

    Article  Google Scholar 

  • Briggs JM, Knapp AK, Brock BL (2002b) Expansion of woody plants in tallgrass prairie: a fifteen year study of fire and fire-grazing interactions. American Midland Naturalist 147:287–294

    Article  Google Scholar 

  • Briggs JM, Knapp AK, Blair JM, Heisler JL, Hoch GA, Lett MS, McCarron JK (2005) An ecosystem in transition: causes and consequences of the conversion of mesic grassland to shrubland. BioScience 55:243–254

    Article  Google Scholar 

  • Brown JR, Archer S (1999) Shrub invasion of grassland: recruitment is continuous and not regulated by herbaceous biomass or density. Ecology 80:2385–2396

    Article  Google Scholar 

  • Bryant JP, Tahvanainen J, Sulkinoja M, Julkunen-Tiitto R, Reichardt P, Green T (1989) Biogeographic evidence for the evolution of chemical defense by boreal birch and willow against mammalian browsing. The American Naturalist 134:20–34

    Article  Google Scholar 

  • Burkinshaw AM (2005) Shrub encroachment onto floodplain meadows within the Rocky Mountain Forest Reserve, Alberta. MSc Thesis, University of Alberta, Edmonton, Alberta, Canada, 123 pp

  • Cook JG, Hershey TJ, Irwin LL (1994) Vegetative response to burning on Wyoming Mountain-shrub big game ranges. Journal of Range Management 47:296–302

    Article  Google Scholar 

  • Cormack RGH (1953) A survey of coniferous forest succession in the eastern Rockies. Forestry Chronicles 29(3):218–232

    Google Scholar 

  • DeGroot WJ, Wein RA (1999) Betula glandulosa Michx. response to burning and postfire growth temperature and implications of climate change. International Journal of Wildland Fire 9:51–64

    Article  Google Scholar 

  • DeGroot WJ, Wein RA (2004) Effects of fire severity and season of burn on Betula glandulosa growth dynamics. International Journal of Wildland Fire 13:287–295

    Article  Google Scholar 

  • DeGroot WJ, Thomas PA, Wein RW (1997) Betula nana L. and Betula glandulosa Michx. Journal of Ecology 85:241–264

    Article  Google Scholar 

  • Dunwiddie PW (1977) Recent tree invasion of subalpine meadows in the Wind River Mountains, Wyoming. Arctic and Alpine Research 9(4):393–399

    Article  Google Scholar 

  • Edwards KJ, Schofield JE, Mauquoy D (2008) High resolution paleoenvironmental and chronological investigations of Norse landnám at Tasiusaq, Eastern Settlement, Greenland. Quaternary Research 69:1–15

    Article  Google Scholar 

  • Environmental Systems Research Institute (ESRI) (2002) Arcview version 3.X for windows. Redlands, CA, USA

  • Flannigan MD, Van Wagner CE (1991) Climate change and wildfire in Canada. Canadian Journal of Forest Research 21:66–72

    Article  Google Scholar 

  • Government of Alberta (2000) Forest reserves act. Chapter/regulation F-20 RSA 2000. ISBN#0779728203

  • Hanson WR (1973) History of the eastern rockies forest conservation board 1947–1973. Eastern Rockies Forest Conservation Board, unpublished Alberta Forest Service report. Edmonton, Alberta, 54 pp

  • Hebblewhite M, Merrill EH, McDonald TL (2005) Spatial decomposition of predation risk using resource selection functions: an example in a wolf-elk predator-prey system. Oikos 111:101–111

    Article  Google Scholar 

  • Hebblewhite M, Merrill EH, McDermid G (2008) A multi-scale test of the forage maturation hypothesis in a partially migratory ungulate population. Ecological Monographs 78:141–166

    Article  Google Scholar 

  • Heisler JL, Briggs JM, Knapp AK, Blair JM, Seery A (2004) Direct and indirect effects of fire on shrub density and aboveground productivity in a mesic grassland. Ecology 85:2245–2257

    Article  Google Scholar 

  • Knight CL, Briggs JM, Nellis MD (1994) Expansion of gallery forest on Konza Prairie Research Natural Area, Kansas, USA. Landscape Ecology 9(2):117–125

    Google Scholar 

  • Köchy M, Wilson SD (2001) Nitrogen deposition and forest expansion in the northern Great Plains. Journal of Ecology 89:807–817

    Article  Google Scholar 

  • Lewis HT (1980) Indian fires of spring. Natural History Journal 89:76–81

    Google Scholar 

  • MacDonald GM (1989) Postglacial palaeoecology of the subalpine forest-grassland ecotone of southwestern Alberta: new insights on vegetation and climate change in the Canadian Rocky Mountains and adjacent foothills. Palaeography, Palaeoclimatology, Palaeoecology 73:155–173

    Article  Google Scholar 

  • Mast NJ, Veblen TT, Hodgson ME (1997) Tree invasion within a pine/grassland ecotone: an approach with historical aerial photography and GIS modeling. Forest Ecology and Management 93:181–194

    Article  Google Scholar 

  • Moss EH (1983) Flora of Alberta. University of Toronto Press, Toronto, ON, 687 pp

    Google Scholar 

  • Pengelly I, Hamer D (2006) Grizzly bear use of pink hedysarum roots following shrubland fire in Banff National Park, Alberta. Ursus 17(2):124–131

    Article  Google Scholar 

  • Petranka JW, McPherson JK (1979) The role of Rhus copallina in the dynamics of the forest-prairie ecotone in North Central Oklahoma. Ecology 60:956–965

    Article  Google Scholar 

  • Rayner MR (1984) Ecological land classification and evaluation: Ram–Clearwater. Resource evaluation branch, resources evaluation and planning division, Alberta energy and natural resources, Edmonton, Alberta, Canada

    Google Scholar 

  • Schlesinger WH, Reynolds JF, Cunningham GL, Huennecke LF, Jarrell WH, Virginia RA, Whitford WG (1990) Biological feedbacks in global desertification. Science 247:1043–1048

    Article  CAS  Google Scholar 

  • Singh A (1989) Digital change detection techniques using remotely sensed data. International Journal of Remote Sensing 10:989–1003

    Article  Google Scholar 

  • Society for Range Management (1989) A glossary of terms used in range management, 3rd edn. Society for Range Management, Denver, CO, USA

  • Strong WL, Leggat KR (1992) Ecoregions of Alberta. Alberta Forestry, Lands and Wildlife, Resource Information Branch, Edmonton, Alta. T/245, 77 pp

  • Sturm M, Racine C, Tape K (2001) Increasing shrub abundance in the Arctic. Nature 411:546–547

    Article  CAS  Google Scholar 

  • Tueller PT (1989) Remote sensing technology for rangeland management applications. Journal of Range Management 42:442–453

    Article  Google Scholar 

  • Turner MG, Romme WH (1994) Landscape dynamics in crown fire ecosystems. Landscape Ecology 9:59–77

    Article  Google Scholar 

  • Van Auken OW (2000) Shrub invasions of North American semiarid grasslands. Annual Review of Ecology and Systematics 31:197–215

    Article  Google Scholar 

  • Wallace OC, Qi J, Heilma P, Marsett RC (2003) Remote sensing for cover change assessment in southeast Arizona. Journal of Range Management 56:402–409

    Article  Google Scholar 

  • Watkinson AR, Ormed SJ (2001) Grasslands grazing and biodiversity: editor’s introduction. Journal of Applied Ecology 38:233–237

    Article  Google Scholar 

  • Weerstra BG (1990) Elk creek rangeland reference area range use, history, condition and trend. Biota Consultants, Cochrane, Alberta. Forest Land Use Branch, Range Management Section, Edmonton Alberta, Canada

  • Weis IM, Hermanutz LA (1988) The population biology of the arctic dwarf birch, Betula glandulosa: seed rain and the germinable seedbank. Canadian Journal of Botany 66:2055–2061

    Google Scholar 

  • Wessman CA, Archer S, Johnson LC, Asner GP (2004) Woodland expansion in U.S. grasslands: assessing land cover change and biogeochemistry impacts. In: Guttman G, Janetos A, Skole D (eds) Land change science: observing, monitoring and understanding trajectories of change on the Earth’s surface. Kluwer Academic Publishers, Dordrecht, Netherlands, pp 185–208

    Google Scholar 

  • West NE (1993) Biodiversity of rangelands. Journal of Range Management 46:2–13

    Article  Google Scholar 

  • Willms WD, Smoliak S, Dormaar JF (1985) Effects of stocking rate on a rough fescue grassland vegetation. Journal of Range Management 38:220–225

    Article  Google Scholar 

  • Willoughby MG (2000) Rangeland reference areas: species composition changes in the presence and absence of grazing and fire on the rough fescue-hairy wildrye dominated community types of the Upper Foothills Subregion. Lands and forest services division, Edmonton, Alberta

    Google Scholar 

  • Willoughby MG (2001) Range plant community types and carrying capacity guides for the Upper Foothills Subregion. Alberta Sustainable Development, Public Lands. Pub No. T/356. Edmonton, Alberta, Canada

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Acknowledgments

This research was funded by Alberta Sustainable Resource Development, the Alberta Conservation Association, and the University of Alberta. We thank Drs. Peter Crown, Evelyn Merrill and Bob Hudson for their helpful comments on an earlier version of this manuscript, and thank Brent Finnestead for field assistance, as well as Rick Pelletier for assistance with the GIS analysis. We also thank 4 anonymous reviewers for helpful advice on improving the manuscript.

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Authors and Affiliations

  1. Rangeland Management Branch, Alberta Sustainable Resource Development, #211, 4920-51 Street, Red Deer, AB, T4N 6K8, Canada

    Angela M. Burkinshaw

  2. Department of Agricultural, Food and Nutritional Science, 410E Agriculture/Forestry Center, University of Alberta, Edmonton, AB, T6G 2P5, Canada

    Edward W. Bork

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  1. Angela M. Burkinshaw
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Correspondence to Edward W. Bork.

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Burkinshaw, A.M., Bork, E.W. Shrub Encroachment Impacts the Potential for Multiple Use Conflicts on Public Land. Environmental Management 44, 493–504 (2009). https://doi.org/10.1007/s00267-009-9328-2

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  • DOI: https://doi.org/10.1007/s00267-009-9328-2

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