Margaret Trani Griep, Regional Wildlife Ecologist, Southern Regional Office;
Patricia N. Manley, Institute of Pacific Islands Forestry, Pacific Southwest Research Station.
An archived version of this topic paper is available.
Biological diversity refers to the variation among living organisms and the ecological complexes of which they are a part. This includes the interrelated nature of genetics, species, and populations across the landscape (1). Biological diversity is essential to maintaining ecosystem processes and services; when loss occurs, ecosystem functionality is reduced (2, 3, 4). Losses of biological diversity over the past century have been unprecedented with environmental stressors such as land-use change, habitat degradation, landscape fragmentation, pollutants, and invasive species taking their toll.
Climate change has become an additional stress on species and communities, one that is expected to increase with time (5). Average temperatures in the United States have risen 2°F over the past half-century (6). The U. S. Global Change Research Program (7) reports that Alaska has warmed at twice the rate (3.4°F) during the same time period, causing reduced sea ice, glacier retreat, and permafrost warming. In the Southeast, fall precipitation has increased 30% and the number of freezing days has declined 4-7 days per year (7). Rising winter temperatures in the Northeast has resulted in longer growing seasons, less winter precipitation falling as snow, and earlier peak river flows. Heat waves, severe drought, and declining water resources are becoming issues in the Southwest and Great Plains (8). Higher temperatures (1.5°F - 4°F) in the Northwest have contributed to earlier snowmelt and reduced stream flows during the summer (9). Sea level rise, high water temperatures, and ocean acidification are concerns in coastal regions.
Questions exist about the challenges that these climate changes pose to biological diversity. Species respond to environmental conditions based on habitat needs and physiological tolerances (10), which in turn influences community composition, structure, and resilience (11). There may be shifts in the geographic range of many species, influencing seasonal movement, recruitment, and mortality (12). Changes in phenology (e.g., timing of resource availability, advances in flowering or nesting dates) may alter predator-prey, competitive interaction, and herbivore-vegetation dynamics (13, 1). Ecological niches may change at a pace slower than expectations for climate change (14); similarly, the pace of climate change will likely exceed the dispersal rate of several species (15). Existing communities may dissociate as species follow the range of suitable conditions, meaning that previously co-occurring species may move in divergent patterns (16, 17, 18, 19). Recolonization may be limited to areas similar to the range core (20).
Characteristics of species and communities at risk include those with restricted geographic ranges, fragmented distributions, and those that occur at the margins of their range. Other characteristics include limited dispersal ability, low genetic diversity, strong affinity to aquatic habitats, narrow physiological tolerance, and late maturation (18). Climate change may exacerbate these risks. For example, amphibians associated with cool, moist conditions may be subject to microclimates beyond their tolerance. Ephemeral streams and ponds may be especially vulnerable to drying with variable precipitation patterns. The small or disjunct populations that often characterize species of concern are likely to be impacted by stochastic climatic events and may not have the ability to adapt to a changing climate.
Climate change has been shown to affect the geographic range of species along elevational gradients (21, 22). Northern-temperate birds have shifted their ranges to higher latitudes, and tropical birds have shifted their breeding ranges to higher altitudes (11). These range shifts appear to have affected migration strategies, where success will depend on the rate of climate change relative to essential habitat needs and key community interactions. In the Southwest, small mammals have expanded their ranges upward in elevation while high-elevation species have contracted theirs, leading to changes in community composition (22). The elevation range shifts of butterfly species recorded in the Sierra Nevada Mountains may continue (23).
There are a number of other changes in biodiversity that are expected to result from climate change. Eastern tree species richness is projected to increase as temperatures warm (24), with the expansion of oak-hickory complex northward and contraction of aspen-birch habitat (25). Old-growth forests in the Northwest (26) and high-elevation forests (such as the spruce-fir complex) in the South (27) and elsewhere (25) appear particularly vulnerable. Rising temperatures may influence forest growth due to drought stress and declining soil moisture. This will increase the frequency of pine beetle and other insect attacks; milder winters may encourage the early emergence of other forest pests. Neotropical migratory birds that are sensitive to climate (i.e., climate associates) may change their migratory arrival in spring, as is being currently observed in the West (28).
Water-limited areas (e. g., weather-dependent, ephemeral) and aquatic systems are also expected to be vulnerable to change (29, 30, 31). Changes in water temperatures may result in reduced oxygen levels in streams and lakes, leading to declines in aquatic species diversity and stress on coldwater fisheries. Increased water temperatures in the Caribbean and Pacific Islands may continue to threaten coral reefs (32), shellfish, and other species. Barrier islands will be vulnerable to severe storm events, sea level rise, and saltwater intrusion (33), leading to declines in coastal wetlands and marshes (6). Communities along the Atlantic Coast and Gulf of Mexico supporting high concentrations of federally-listed species and migratory shorebirds will be especially vulnerable (27).
Options for Management
Climate change creates uncertainty about how best to design adaptation and mitigation strategies (34). Static management can no longer be assumed (35); the environment will change in a directional way rather than varying around a mean condition (36). The planning focus will be on spatial and temporal scales that are broader and longer than typically considered. Management for resilient forests and resistance to invasive species may become more focused in the future to account for changing climate, land use, and human population expansion. Difficult decisions on where to spend limited resources may favor some species over others. For example, restoration strategies may shift away from coastal areas under risk of sea level rise. As future impacts occur across large areas, the appropriate decision-making level may shift to cover landscape and regional scales.
Management options are further challenged by estimating the adaptive abilities of species where no current ecological analog exists. It will be critical to maintain conditions that allow for changes in species composition and migration while maintaining system function and process. The indirect effects on diversity created by shifting ranges and habitat associations are unknown (29, 37); predicting biogeographical shifts will be challenging.
Knowledge is evolving as researchers refine levels of uncertainty and contrast anthropogenic activities altering atmospheric composition with natural climate variability. Ecological response models (occupancy, vegetation, other) using downscaled climate data will play important roles. Management options that can help maintain biodiversity even where uncertainties exist include:
- Vulnerability assessments to identify species and communities at risk, including strategies to maximize persistence, dispersal, and ecosystem resilience (6).
- Ecological risk evaluation for areas of imminent change.
- Identification of barriers to migration and identification of mitigation measures to enhance landscape connectivity into future planning efforts.
- Long-term monitoring strategies to identify patterns in disturbance and phenology including the evaluation of current environmental indicators of biological diversity and resiliency.
- Adaptive restoration strategies based on predicted species range expansion and contraction, storm surge proximity, and seal level rise.
- Enhancement of genetic diversity to provide resilience against environmental stressors.
- Development of innovative tools for integrating climate change science into land management planning.
Trani Griep, M.; Manley, P. 2012. Biodiversity and Climate Change. (January 4, 2012). U.S. Department of Agriculture, Forest Service, Climate Change Resource Center. www.fs.usda.gov/ccrc/topics/biodiversity
Gitay, H.; Suarez, A.; Watson, R.T.; Dokken, D.J. 2002. Climate change and biodiversity. Intergovernmental panel on climate change IPCC Technical Paper V.
Glick, P.; Stein, B.A.; Edelson, N.A. 2011. Scanning the conservation horizon: A guide to climate change vulnerability assessment. National Wildlife Federation, Washington, D.C. 168 pp.
Lawler, J. L.; Shafer, S. L.; White, D.; Kareiva, P.; Maurer, E. P.; Blaustein, A. R.; Bartlein, P. J. 2009. Projected climate-induced faunal changes in the western hemisphere. Ecology 90:588-597.
Lovejoy, T.E.; Hannah, L.J. (Editors). 2005. Climate change and biodiversity. New Haven, CT: Yale University Press. 440 p.
Sala, O.E.; Chapin, F.S. III; Armesto, J.J.; Berlow, E.; Bloomfield, J.; Dirzo, R.; Huber-Sanwald, E.; Huenneke, L.F.; Jackson, R.B.; Kinzig, A.; Leemans, R.; Lodge, D.M.; Mooney, H.A.; Oesterheld, M.; Poff, N.L.; Sykes, M.T.; Walker, B.H.; Walker, M.; Wall, D.H. 2000. Global biodiversity scenarios for the year 2100. Science 287: 1770-1774.
Schneider, S.H.; Root, T.L. 2002. Wildlife responses to climate change: North American Case Studies. Washington, DC: Island Press. 437 p.
Walther, G.R.; Post, E.; Convey, P.; Menzel, A.; Parmesan, C.; Beebee, T.J.C.; Fromentin, J.M.; Hoegh-Guldberg, O.; Bairlein, F. 2002. Ecological responses to recent climate change. Nature 416: 389-395.
Climate Change and Wildlife Habitat
An analysis of potential national effects of climate change on wildlife habitat is being addressed by RMRS scientists through the estimation of an index of climate change stress to terrestrial biodiversity in order to identify regional hotspots of climate change impacts. This research focuses on management strategies for climate change in the states' Wildlife Action Plans.
Contact: Linda Joyce, Curt Flather
Climate change influences on distributions of sculpin in western Montana
Sculpin are ecologically important, small-bodied fishes that live on the bottom of cold- and coolwater streams, rivers, and lakes. They are often the most abundant fish in small streams. We studied distributions of two sculpin species in relation to summer stream temperatures since 2006 and obtained historical distribution and temperature data extending back much farther. Water temperature is an important factor in determining summer distributions of sculpins in the study area, and we are exploring how stream warming influences sculpin distributions.
Contact: Susan B. Adams
Modeling potential future habitats for trees and birds in the eastern U.S.
Our group, the Landscape Change Research Group, from Delaware, OH lab of the Northern Research Station, have been modeling potential changes in suitable habitat for trees and birds of the eastern US. These maps are available online at www.nrs.fs.fed.us/atlas. We also look at dispersal potentials through another modeling toolset, and work with modification factors to understand more about the factors not readily modeled.
Contact: Louis Iverson
Species Distributions and Non-analog Climate
It is difficult to predict how species will respond under novel environments, because many species distribution models are calibrated for present conditions. It is estimated that by 2100, a quarter or more of the Earth's land surface may experience new climatic conditions that have no modern analog. This presents a challenge in anticipating the impacts of global change on biodiversity.
Contact: William Hargrove
Stream temperature influences on warmwater fish and crayfish communities, with emphasis on Yazoo darters
We are exploring how summer stream temperatures influence fish and crayfish distributions in Mississippi and establishing long-term stream temperature recording sites. A focal species for the study is theYazoo darter, a small, warmwater fish endemic to north-central Mississippi. This species appears to be restricted to stream segments with high groundwater discharge, and we are investigating whether the species' apparent groundwater dependence is due to temperature influences of groundwater.
Contact: Susan B. Adams, Mel Warren
Tropical Forest Mycology
The Center for Forest Mycology Research (CFMR), part of the Northern Research Station, leads critical research on the biology of tropical fungi native to Hawaii, US territories in the Caribbean and to other countries in the Caribbean Basin. The primary goals of this research are to: (1) recognize emerging tropical forest diseases, especially those with the potential to spread to the continental US and (2) identify the effects of environmental change on the distributions of beneficial and harmful forest fungi.
Contact: D. Jean Lodge
- CCSP, 2008: Preliminary review of adaptation options for climate-sensitive ecosystems and resources. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. [Julius, S.H.; West, J.M.; Baron, J.S.; Joyce, L.A.; Kareiva, P.; Keller, B.D.; Palmer, M.A.; Peterson, C.H.; Scott, J.M. (Authors)]. U.S. Environmental Protection Agency, Washington, DC. 873 pp.
- Kremen, C. 2005. Managing ecosystem services: What do we need to know about their ecology? Ecology Letters 8: 468-479.
- Loreau, M.; Naeem, S.; Inchausti, P.; Bengtsson,J.; Grime, J.P.; Hector, A.; Hooper, D.U.; Huston, M.A.; Raffaelli, D.; Schmid, B.; Tilman, D.; Wardle, D.A. 2001. Biodiversity and ecosystem functioning: Current knowledge and future challenges. Science 294(5543): 804â€“808.
- Reich, P.B.; Tilman, D.; Naeem, S.; Ellsworth, D.S.; Knops, J.; Craine, J.; Wedin, D.; Trost, J. 2004. Species and functional group diversity independently influence biomass accumulation and its response to CO2 and N. Proceedings of the National Academy of Science 101(27): 10101-10106.
- IPCC, 2007: Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri, R.K.; Reisinger, A. (eds.)]. IPCC, Geneva, Switzerland, 104 pp. .
- Glick, P.; Stein, B.A.; Edelson, N.A. 2011. Scanning the conservation horizon: A guide to climate change vulnerability assessment. National Wildlife Federation, Washington, D.C. 168 pp.
- U. S. Global Change Research Program (USGCRP). 2009. Global climate change impacts in the United States. Karl, T.R.; Melillo, J.M.; Peterson, T.C. (eds). Cambridge University Press.
- Lettenmaier, D.; Major, D.; Poff, L.; Running, S. 2008. Water Resources. In:The effects of climate change on agriculture, land resources, water resources, and biodiversity in the United States. Synthesis and Assessment Product 4.3 Department of Agriculture, Washington, DC. p. 121-150
- Barnett, T. P.; Pierce, D.W.; Hidalgo, H.G.; Bonfils, C.; Santer, B.D.; Das, T.; Bala, G.; Wood, A.W.; Nozawa, T.; Mirin, A.A.; Cayan, D.R.; Dettinger, M.D. 2008. Human-induced changes in the hydrology of the western United States. Science 319(5866): 1080-1083.
- Currie, D.J. 2001. Projected effects of climate change on patterns of vertebrate and tree species richness in the conterminous United States. Ecosystems 4: 216-225.
- LaSorte, F; Jetz, W. 2010. Avian distributions under climate change: Towards improved projections. Journal of Experimental Biology 213: 862-869.
- Inouye, D.W.; Barr, B.; Armitage, K.B.; Inouye, B.D. 2000. Climate change is affecting altitudinal migrants and hibernating species. Proceedings of the National Academy of Sciences 97(4): 1630-1633.
- Kelly, A. E.; Goulden, M.L. 2008. Rapid shifts in plant distribution with recent climate change. Proceedings of the National Academy of Sciences of the United States of America 105: 11823-11826.
- Martinez-Meyer, E.; Peterson, A.T.; Hargrove, W.W. 2004. Ecological niches as stable distribution constraints on mammal species, with implications for Pleistocene extinctions and climate change projects for biodiversity. Global Ecology and Biogeography 13: 305-314.
- Hansen, A.; Dale, V. 2000. Biodiversity in U.S. forests under global climate change. Ecosystems, 4, 161-163.
- Jeschke, J. M.; Strayer, D. L. 2008. Usefulness of bioclimatic models for studying climate change and invasive species. Annals of the New York Academy of Sciences 1134: 1-24.
- Jackson, S. T.; Betancourt, J. L.; Booth, R. K.; Gray, S. T. 2009. Ecology and the ratchet of events: Climate variability, niche dimensions, and species distributions. Proceedings of the National Academy of Sciences 106(2): 19685-19692.
- Midgley, G.F.; Hannah, L.; Millar, D.; Rutherford, M.C.; Powrie, L.W. 2002. Assessing the vulnerability of species richness to anthropogenic climate change in a biodiversity hotspot. Global Ecology and Biogeography 11: 445-451.
- Parmesan, C., 2005. Biotic response: range and abundance changes. Pages 41-55 In Lovejoy, T.E.; Hannah, L. (Editors). Climate Change and Biodiversity. Yale University Press, New Haven, CN.
- Guralnick, R. 2006. The legacy of past climate and landscape change on speciesâ€™ current experienced climate and elevation ranges across latitude: a multispecies study utilizing mammals in western North America. Global Ecology and Biogeography, 15, 505-518.
- Parmesan, C.; Yohe, G. 2003. A globally coherent fingerprint of climate change impacts across natural systems. Nature 421: 37-42.
- Moritz, C.; Patton, J.L.; Conroy, C.J.; Parra, J.L.; White, G.C.; Beissinger, S.R. 2008. Impact of a century of climate change on small-mammal communities in Yosemite National Park, USA. Science 322: 261-264.
- Forister, M.L.; McCall, A.C.; Sanders, N.J.; Fordyce, J.A.; Thorne, J.H.; O'Brien,J.; Waetjen, D.P.; Shapiro, A.M. 2010. Compounded effects of climate change and habitat alteration shift patterns of butterfly diversity. Proceedings of the National Academy of Science, 107 (5), 2088-2092.
- Joyce, L. A.; Blate, G.M.; Littell, J.S.; McNulty, S.G.; Millar,C.I.; Moser,S.C.; Peterson, D. L. 2008. National forests.In:Preliminary review of adaptation options for climate-sensitive ecosystems and resources. A report by the U.S. climate change science program and the subcommittee on global change research. U. S. Environmental Protection Agency. p. 1-127
- Iverson, L. R.; Prasad, S. N.; Matthews, S. N.; Peters, M. 2008. Estimating potential habitat for 134 eastern US tree species under six climate scenarios. Forest Ecology and Management 254: 390-406.
- Shugart, H.; Sedjo, R.; Sohngen, B. 2003. Forests & global climate change potential impacts on U.S. forest resources. Center for Climate and Energy Solutions.
- Trani, M. K.; Collins, B. In Press. Wildlife and forest communities. In Wear, D. and J. Greis, Editors. The Southern Forest Futures Assessment. USDA Forest Service. General Technical Report. Asheville, NC.
- Moser, S.; Franco, G.; Pittiglio, W.; Chou, W.; Cayan, D. 2009. The future is now: An update on climate change science impacts and response options for California. California Energy Commission Public Interest Energy Research Program, CEC-500-2008-071, 1-114.
- Hampe, A.; Petit, R.J. 2005. Conserving biological diversity under climate change: The rear edge matters. Ecology Letters. 8: 461-467.
- Malcolm, J.R.; Liu, C.; Neilson, R.P.; Hansen, L.; Hannah, L. 2006. Global warming and extinctions of endemic species from biodiversity hotspots. Conservation Biology 20(2): 538-548.
- Brooks, R.T. 2009. Potential impacts of global climate change on the hydrology and ecology of ephemeral freshwater systems of the forests of the northeastern United States. Climatic Change 95: 469-483.
- Harvell, C.D.; Kim, K.; Burkholder, J.M.; Colwell, R.R.; Epstein, P.R.; Grimes, D.J.; Hoffmann, E.E.; Lipp, E.K.; Osterhaus, A.D.; Overstreet, R.M.; Porter, J.W.; Street, G.W.; Vasta, G.R. 2007. Emerging marine diseases: Climate links and anthropogenic factors. Science 285: 1505-1510.
- CCSP, 2008: The effects of climate change on agriculture, land resources, water resources, and biodiversity in the United States. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Backlund, P.; Janetos, A.; Schimel, D.; Hatfield, J.; Boote, K.; Fay, P.; Hahn, L.; Izaurralde, C.; Kimball, B.A.; Mader, T.; Morgan, J.; Ort, D.; Polley, W.; Thomson, A.; Wolfe, D.; Ryan, M.G. ; Archer, S.R.; Birdsey, R.; Dahm, C.; Heath, L.; Hicke, J.; Hollinger, D.; Huxman, T.; Okin, G.; Oren, R; Randerson, J.; Schlesinger, W.; Lettenmaier, D.; Major, D.; Poff, L.; Running, S.; Hansen, L.; Inouye, D.; Kelly, B.P.; Meyerson, L.; Peterson, B.; Shaw, R. U.S. Department of Agriculture, Washington, DC., USA. 362 pp.
- Thomas, C.D.; Cameron, A.; Green, R.E.; Bakkenes, M.; Beaumont, L.J.; Collingham, Y.C.; Erasmus, B.F.N.; Ferreira de Siqueira, M.; Grainger, A.; Hannah, L.; Hughes, L.; Huntley, B.; van Jaarsveld, A.S.; Midgley, G.F.; Miles, L.; Ortega-Huerta, M.A.; Peterson, A.T.; Phillips, O.L.; Williams, S.E. 2004. Extinction risk from climate change. Nature 427: 145-148.
- Hayward, G. D.; Flather, C.H.; Uloth, E.; Safford, H.D.; Cleaves, D.A. 2009. Managing fish and wildlife habitat in the face of climate change: USDA Forest Service perspective. North American Wildlife and Natural Resources Conference 74:98-109.
- Milly, P.C.D.; Betancourt, J.; Falkenmark, M.; Hirsch, R.M.; Kundzewicz, Z.W.; Lettenmaier, D.P.; Stouffer, R. J. 2008. Stationarity is dead: Whither water management? Science 319:573-574.
- Williams, J.W.; Jackson S.T. 2007. Novel climates, no-analog communities, and ecological surprises. Frontiers in Ecology and the Environment 5:475-482.