PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of f1000bioLatest ContentReportsReportsReports
 
F1000 Biol Rep. 2009; 1: 16.
Published online 2009 February 24. doi:  10.3410/B1-16
PMCID: PMC2920684

Climate change and biodiversity conservation: impacts, adaptation strategies and future research directions

Abstract

The impacts of climate change pose fundamental challenges for current approaches to biodiversity conservation. Changing temperature and precipitation regimes will interact with existing drivers such as habitat loss to influence species distributions despite their protection within reserve boundaries. In this report we summarize a suite of current adaptation proposals for conservation, and highlight some key issues to be resolved.

Introduction and context

Changing temperature and precipitation regimes [1] are expected to interact with other drivers to impact a range of biological processes and influence species distributions [2,3] (Figure 1). In the past 5 years a growing body of empirical evidence has documented climate-change-attributed changes in processes, including phenology [4-6], net primary production [7], and species interactions [8]. Changes in species distributions have also been observed in both above-ground [3,9-11] and below-ground communities [12].

Figure 1.
Diagrammatic representation of some of the global change drivers, mediating drivers and biodiversity (pattern) responses in terrestrial ecosystems

This situation poses fundamental challenges to existing approaches for biodiversity conservation because targets (for example, species) are currently managed within spatially and temporally static reserves [13-18]. As a result of changing species distributions, some populations and species will no longer be viable in reserves created for their protection. Additionally, altered disturbance regimes may enhance the ability of invasive species to colonize reserves more easily [19].

Thus, a central unresolved question in conservation biology is: how can we manage for biodiversity objectives in an era of accelerated climate change? In this report we provide a brief overview of a current suite of proposed adaptation approaches, and identify some future challenges and key issues to be resolved. Both mitigation and adaptation strategies are crucial to respond to climate change. Although reserves can play a role in carbon storage and sequestration - for example, through initiatives such as reducing emissions from deforestation and degradation (one aspect of climate change mitigation) - here we focus solely on adaptation strategies.

Major recent advances

Below we highlight four commonly proposed adaptation strategies for biodiversity conservation given climate change. In this overview report we focus on a selection of commonly proposed in situ adaptation strategies in response to the impacts of climate change. For a journalistic overview of ex situ strategies, such as captive breeding, seed and gene banking, in the context of responding to climate change, the reader is referred to [20].

The first three approaches seek to reduce extinction risk primarily by addressing the effects of climate change on species distributions (the pattern), and in part by passively influencing mediating drivers (for example, providing corridors for movement). The last considers a more controversial interventionist option (Table 1).

Table 1.
Selection of central current proposed adaptation approaches for conservation: mechanisms and types of intervention for minimizing extinction risk given climate change

Managing the matrix as a buffer should both protect core populations (but often not in the matrix, rather by insulating reserves) and also facilitate shifts across a landscape; new and dynamic reserves function primarily by protecting core populations and also by accommodating (rather than facilitating) target movement.

New reserves and corridors

The most common proposed approach for conservation adaptation is to expand linked networks of protected areas including migration corridors [15,17,18,21-23]. These researchers argue that the existing network does not provide enough area to allow for organisms to respond autonomously to changing climatic conditions.

The principal purpose of new protected areas is to mitigate the risk of extinction by providing the potential for species distributions to shift; a secondary contribution is that they may also enhance micro-evolutionary potential through enhanced population size and diversity. Therefore, corridors may reduce extinction risk by enabling the passive shifting of some species to new geographic ranges, and by reinforcing species distributions (in a metapopulation context).

A crucial challenge for this approach is determining where to site corridors and new reserve areas. The current state-of-the-science is to use species distribution models or bioclimate envelope models to generate projections of future species’ responses to various climate scenarios [24-27]. Many view this information as providing essential insight into the strategic siting of new protected areas [28]. At the same time, myriad uncertainties impact the validity of these projections [29-34]. Efforts to address these uncertainties are ongoing [27,35], but many uncertainties may remain (or even increase) within decision-making time frames nonetheless.

Schemes for siting new areas may be more robust to uncertainties by incorporating coarse scale environmental gradients, such as edaphic and elevational ranges (for example, [21]).

Matrix as buffers

As a complement to protected areas expansion, many researchers highlight the importance of matrix areas [36,37] or the wider landscape, as being particularly crucial for biological adaptation in an era of change [15,21]. For example, some land uses, such as forestry or agro-forestry (or lower impact marine activities), may provide a spatial buffer for populations as they respond to climate change and move outside core reserves. In order for this proposal to be effective, matrix areas must be of sufficient size, and landowners must be willing to adjust their activities as monitoring indicates [21]. Incentives may increase the viability of this proposal. The logic of this approach is similar to new protected areas and corridors: more benign matrix areas may passively facilitate species shifts by promoting movement across land- and seascapes; they may also reinforce species distributions at fine scales (around reserves).

Dynamic reserves

The management of matrix areas for biodiversity objectives further supports a third proposal. Dynamic reserves implemented on managed landscapes (or seascapes) are areas whose locations and levels of protection change through time and space [18,22,38,39]. This approach may be particularly important in areas where there is little spatial opportunity available for new core protected areas. At the same time, the issue of ownership and property rights requires further examination in different contexts in order to more fully understand the implementation challenges of this potential approach in particular localities. This approach involves the future passive facilitation of shifting species distributions in response to future conditions, rather than prediction of conditions.

Assisted colonization

More controversial is the interventionist proposal for ‘assisted migration’ [40,41] or ‘assisted colonization’ [42]. Both describe a management option in which species are deliberately introduced into an area where it has not existed in recent history for the purpose of achieving a conservation objective. This proposal has emerged in response to the mounting evidence that some species may not be able to track changing climatic conditions quickly enough [3,43], or because there are natural or human barriers in the way. This approach would involve actively shifting species distributions.

The assisted colonization proposal is at odds with current reserve management in which substantial efforts are directed at keeping non-native species out. It also carries with it substantial risks because introduced species may become invasive and displace other valued ecosystem elements. Nevertheless, assisted colonization may be seen as a necessary last resort in some cases. In anticipation of this, Hoegh-Guldberg et al. [42] have proposed a framework for decision making within which the costs, benefits and risks of the translocation event would be evaluated. Other researchers have inferred the risk of potential invasion of assisted colonization from comparisons of intra-continental and inter-continental past invasions [44].

Future directions

In this last section we identify a collection of key challenges and issues to be resolved for reserve management suited for an era of change. We divide these challenges into five categories: focus on processes, projections and uncertainties, monitoring, implementation, and norms and expectations.

Focus on processes

In the main, conservation activities have focussed on maintaining biodiversity patterns and indirectly enabling natural processes: for example, by protecting space for species to exist (represented by the first three categories referred to above). As climate change influences mediating drivers, the attributes that make certain places conducive to species flourishing (critical habitat) will change, and in some cases disappear. For species whose critical habitat changes dramatically or disappears, it will be increasingly necessary to consider approaches that involve the active management of mediating drivers.

Restoration activities have long involved management of disturbance regimes, ecosystem function, and species interactions. Adapting to the impacts of climate change may require more such active management, including assisted colonization, and other interventions, such as enhancement of evolutionary adaptation [45], and active maintenance of pre-climate change processes and conditions.

Projections and uncertainties

A key area of future research is to improve our capacity for forecasting species responses to changing climate - for example, by incorporating biotic interactions in bio-climate models [46], and refining species-specific process-based models [47]. Other areas include the longstanding scientific challenge of understanding when a given species will become invasive in a given context [44]. Efforts to reduce the ecological uncertainties just mentioned will represent a key contribution to the literature on adaptive reserve management.

In addition to ecological uncertainties, there are various parametric and model uncertainties relating to species distribution models. This includes uncertainties relating to so-called ‘unknown unknowns’; where key processes are not yet recognized, understood or incorporated into model structure, or as parameters. Yet such processes may play critical roles in ecosystem dynamics nonetheless. Moreover, there are uncertainties relating to the climate scenario models that influence the outputs of envelope models [48]. Lastly, there are critical socio-political uncertainties (in values, impacts, responses and feedbacks).

Thus, a second key area of future research is the development of conservation approaches that are robust to uncertainty, recognizing that many of the above uncertainties are irreducible. As ecological and social systems co-adapt, non-linear dynamics will lead to perpetually surprising outcomes [49]. Therefore, even with the best scientific research and most comprehensive models, species responses may surprise us. Indeed, uncertainties may also increase with new research and insights [50]. Thus, the implementation of safe-to-fail adaptive management policies may be as or more important than efforts to reduce uncertainties.

Monitoring

In many ways, conservation adaptation requires recognition of what is changing and where (for example, assisted migration, dynamic reserves). Thus, there is an urgent need for monitoring of impacts. While existing monitoring programs could be adapted and used for this purpose, programs specifically targeted to assessing the impacts of climate change would support the most effective adaptation responses possible under highly uncertain circumstances.

Implementation

So far, the adaptation proposals outlined above have focussed primarily on biological dimensions. This effort has provided a critical foundation, but land-use decisions, including reserves, are social decisions made in the context specific places. Therefore, a key area of future research is to identify through applied case studies the factors that determine the relative receptivity or resistance of communities to new and additional conservation measures. This effort will provide crucial insights by which conservationists can foster socially sustainable conservation action.

Changing norms and expectations for reserve management

To date, core protected areas have been managed with a preferred minimum intervention (with exceptions for active management including controlled burns, programs to limit grazers, and efforts to minimize the impacts and distributions of invasive species, for example). Proposals for more widespread intervention, including assisted colonization, raise many unanswered questions. When do we intervene and to what extent? To what extent and under what circumstances are we willing to sacrifice the persistence of one species to save another? Who decides? And by what decision process? Addressing these questions, including latent and even more controversial proposals for conservation triage [51], will be a key challenge moving forward.

Ultimately, one of the biggest challenges to fostering biological adaptation may be a willingness across stakeholders, scientists and managers to re-calibrate existing expectations of nature and reserves in responding to an era of global change.

Acknowledgments

Funding for this work was provided by the National Science Foundation (SES-0345798) through the Climate Decision Making Center (CDMC) at Carnegie Mellon University, and a University Graduate Fellowship from the University of British Columbia.

Notes

The electronic version of this article is the complete one and can be found at: http://F1000.com/Reports/Biology/content/1/16

Notes

Competing interests

The authors declare that they have no competing interests.

References

2. Thomas CD, Cameron A, Green RE, Bakkenes M, Beaumont LJ, Collingham YC, Erasmus BF, De Siqueira MF, Grainger A, Hannah L, Hughes L, Huntley B, Van Jaarsveld AS, Midgley GF, Miles L, Ortega-Huerta MA, Peterson AT, Phillips OL, Williams SE. Extinction risk from climate change. Nature. 2004;427:145–8. doi: 10.1038/nature02121. [PubMed] [Cross Ref]
3. Parmesan C. Observed ecological and evolutionary impacts of contemporary climate change. Annu Rev Ecol Syst. 2006;37:637–69. doi: 10.1146/annurev.ecolsys.37.091305.110100. [Cross Ref]
4. Root TL, Price JT, Hall KR, Schneider SH, Rosenzweig C, Pounds JA. Fingerprints of global warming on wild animals and plants. Nature. 2003;421:57–60. doi: 10.1038/nature01333. [PubMed] [Cross Ref]
5. Parmesan C, Yohe G. A globally coherent fingerprint of climate change impacts across natural systems. Nature. 2003;421:37–42. doi: 10.1038/nature01286. [PubMed] [Cross Ref]
6. Menzel A, Sparks TH, Estrella N, Koch E, Aasa A, Ahas R, Alm-Kubler K, Bissolli P, Braslavska O, Briede A, Chmielewski FM, Crepinsek Z, Curnel Y, Dahl A, Defila C, Donnelly A, Filella Y, Jatczak K, Mage F, Mestre A, Nordli O, Penuelas J, Pirinen P, Remisova V, Scheifinger H, Striz M, Susnik A, Van Viet AJH, Wielgolaski F-E, Zach S, Zust A. European phenological response to climate change matches the warming pattern. Glob Change Biol. 2006;12:1969–76. doi: 10.1111/j.1365-2486.2006.01193.x. [Cross Ref]
7. Nemani RR, Keeling CD, Hashimoto H, Jolly WM, Piper SC, Tucker CJ, Myneni RB, Running SW. Climate-driven increases in global terrestrial net primary production from 1982-1999. Science. 2003;300:1560–3. doi: 10.1126/science.1082750. [PubMed] [Cross Ref]
8. Suttle KB, Thomsen MA, Power ME. Species interactions reverse grassland response to changing climate. Science. 2007;315:640–2. doi: 10.1126/science.1136401. [PubMed] [Cross Ref] F1000 Factor 6.4 Must Read
Evaluated by Oswald Schmitz 16 Feb 2007, Christian Korner 17 May 2007
9. Walther GR, Post E, Convey P, Menzel A, Parmesan C, Beebee TJ, Fromentin JM, Hoegh-Guldberg O, Bairlein F. Ecological responses to recent climate change. Nature. 2002;416:389–95. doi: 10.1038/416389a. [PubMed] [Cross Ref]
10. Pounds JA, Bustamante MR, Coloma LA, Consuegra JA, Fogden MP, Foster PN, La Marca E, Masters KL, Merino-Viteri A, Puschendorf R, Ron SR, Sánchez-Azofeifa GA, Still CJ, Young BE. Widespread amphibian extinctions from epidemic disease driven by global warming. Nature. 2006;439:161–7. doi: 10.1038/nature04246. [PubMed] [Cross Ref] F1000 Factor 8.4 Exceptional
Evaluated by Yvonne Graeser 18 Jan 2006, Gabriele Sorci 18 Jan 2006, Edmund Brodie 20 Jan 2006, Mark Lonsdale 10 Feb 2006
11. Lenoir J, Gegout JC, Marquet PA, de Ruffray P, Brisse H. A significant upward shift in plant species optimum elevation during the 20th century. Science. 2008;320:1771. doi: 10.1126/science.1156831. [PubMed] [Cross Ref] F1000 Factor 4.8 Must Read
Evaluated by Robert Sterner 2 Jul 2008, Valerie Eviner 11 Jul 2008
12. Rinnan RA, Michelsen A, Baath E, Jonasson S. Fifteen years of climate change manipulations alter soil microbial communities in a subarctic heath ecosystem. Glob Change Biol. 2007;13:28–39. doi: 10.1111/j.1365-2486.2006.01263.x. [Cross Ref]
13. Peters RL, Darling JDS. The greenhouse effect and nature reserves: Global warming would diminish biological diversity by causing extinctions among reserve species. BioScience. 1985;35:707–17. doi: 10.2307/1310052. [Cross Ref]
14. Halpin PN. Global climate change and natural-area protection: management responses and research directions. Ecol Appl. 1997;7:828–43. doi: 10.1890/1051-0761(1997)007[0828:GCCANA]2.0.CO;2. [Cross Ref]
15. Hannah L, Midgley GF, Millar D. Climate change-integrated conservation strategies. Global Ecol Biogeogr. 2002;11:485–95. doi: 10.1046/j.1466-822X.2002.00306.x. [Cross Ref]
16. Araújo MB, Cabeza M, Thuiller W, Hannah L, Williams PH. Would climate change drive species out of reserves? An assessment of existing reserve-selection methods. Global Change Biol. 2004;10:1618–26. doi: 10.1111/j.1365-2486.2004.00828.x. [Cross Ref]
17. Hannah L, Midgley GF, Andelman S, Araújo MB, Hughes G, Martinez-Meyer E, Pearson R, Williams P. Protected area needs in a changing climate. Frontiers Ecol Environment. 2007;5:131–8. doi: 10.1890/1540-9295(2007)5[131:PANIAC]2.0.CO;2. [Cross Ref]
18. Pressey RL, Cabeza M, Watts M, Cowling RM, Wilson KA. Conservation planning in a changing world. Trends Ecol Evol. 2007;22:583–93. doi: 10.1016/j.tree.2007.10.001. [PubMed] [Cross Ref]
19. Hobbs RJ, Huenneke LF. Disturbance, diversity and invasion: implications for conservation. Conserv Biol. 1992;6:324–37. doi: 10.1046/j.1523-1739.1992.06030324.x. [Cross Ref]
20. Marris E. Bagged and boxed: it's a frog's life. Nature. 2008;452:394–5. doi: 10.1038/452394a. [PubMed] [Cross Ref]
21. Noss RF. Beyond Kyoto: Forest management in a time of rapid climate change. Conserv Biol. 2001;15:578–90. doi: 10.1046/j.1523-1739.2001.015003578.x. [Cross Ref]
22. Hannah L. Protected areas and climate change. Ann NY Acad Sci. 2008;1134:202–12. doi: 10.1196/annals.1439.009. [PubMed] [Cross Ref]
23. Phillips SJ, Williams P, Midgley G, Archer A. Optimizing dispersal corridors for the Cape Proteaceae using network flow. Ecol Appl. 2008;18:1200–11. doi: 10.1890/07-0507.1. [PubMed] [Cross Ref]
24. Midgley GF, Hannah L, Millar D, Rutherford MC, Powrie LW. Assessing the vulnerability of species richness to anthropogenic climate change in a biodiversity hotspot. Global Ecol Biogeogr. 2002;11:445–51. doi: 10.1046/j.1466-822X.2002.00307.x. [Cross Ref]
25. Thuiller W, Lavorel S, Araújo MB, Sykes MT, Prentice C. Climate change threats to plant diversity in Europe. Proc Natl Acad Sci USA. 2005;102:8245–50. doi: 10.1073/pnas.0409902102. [PubMed] [Cross Ref]
26. Lawler J, White D, Neilson RP, Blaustein AR. Predicting climate-induced range shifts: model differences and reliability. Glob Change Biol. 2006;12:1568–84. doi: 10.1111/j.1365-2486.2006.01191.x. [Cross Ref]
27. Thuiller W, Albert C, Araújo MB, Berry PM, Cabeza M, Guisan A, Hickler T, Midgley GF, Paterson J, Schurr FM, Sykes MT, Zimmermann NE. Predicting global change impacts on plant species' distributions: Future challenges. Perspectives Plant Ecol Evol Systematics. 2008;9:137. doi: 10.1016/j.ppees.2007.09.004. [Cross Ref]
28. Williams P, Hannah L, Andelman S, Midgley GF, Araújo MB, Hughes G, Manne L, Martinez-Meyer E, Pearson R. Planning for climate change: identifying minimum-dispersal corridors for the Cape Proteaceae. Conservation Biol. 2005;19:1063–74. doi: 10.1111/j.1523-1739.2005.00080.x. [Cross Ref]
29. Davis AJ, Jenkinson LS, Lawton JH, Shorrocks B, Wood S. Making mistakes when predicting shifts in species range in response to global warming. Nature. 1998;391:783–6. doi: 10.1038/35842. [PubMed] [Cross Ref]
30. Pearson RG, Dawson TP. Predicting the impacts of climate change on the distribution of species: are bioclimate envelope models useful? Global Ecol Biogeography. 2003;12:361–71. doi: 10.1046/j.1466-822X.2003.00042.x. [Cross Ref]
31. Pearson RG, Thuiller W, Araújo M, Martinez-Meyer E, Brotons L, McClean C, Miles L, Segurado P, Dawson TP, Lees DC. Model-based uncertainty in species range prediction. J Biogeogr. 2006;33:1704–11. doi: 10.1111/j.1365-2699.2006.01460.x. [Cross Ref]
32. Araújo MB, Guisan A. Five (or so) challenges for species distribution modelling. J Biogeogr. 2006;33:1677–88. doi: 10.1111/j.1365-2699.2006.01584.x. [Cross Ref]
33. Heikkinen RK, Luoto M, Araújo MB, Virkkala R, Thuiller W, Sykes MT. Methods and uncertainties in bioclimatic envelope modelling under climate change. Prog Phys Geog. 2006;30:751–77. doi: 10.1177/0309133306071957. [Cross Ref]
34. Ibanez I, Clark MC, Feeley K, Hersh M, LaDeau S, BcBride A, Welch NE, Wolosin M. Predicting biodiversity change: outside the climate envelope, beyond the species-area curve. Ecology. 2006;87:1896–906. doi: 10.1890/0012-9658(2006)87[1896:PBCOTC]2.0.CO;2. [PubMed] [Cross Ref]
35. Araújo MB, New M. Ensemble forecasting of species distributions. Trends Ecol Evol. 2007;22:42–7. doi: 10.1016/j.tree.2006.09.010. [PubMed] [Cross Ref]
36. Franklin JF. Preserving biodiversity: Species, ecosystems or landscapes? Ecol Appl. 1993;3:202–5. doi: 10.2307/1941820. [Cross Ref]
37. Daily G. Countryside biogeography and the provision of ecosystem services. In: Raven P, editor. Nature and Human Society: The Quest for a Sustainable World. Washington DC: National Research Council; 1997. pp. 104–13.
38. Bengtsson J, Angelstam P, Elmqvist T, Emanuelsson U, Folke C, Ihse M, Moberg F, Nyström M. Reserves, resilience and dynamic landscapes. Ambio. 2003;32:389–96. doi: 10.1579/0044-7447-32.6.389. [PubMed] [Cross Ref]
39. Rayfield B, James PMA, Fall A, Fortin M. Comparing static versus dynamic protected areas in the Quebec boreal forest. Biol Conserv. 2008;141:438–49.
40. McLachlan JS, Hellmann JJ, Schwartz MW. A framework for debate of assisted migration in an era of climate change. Conserv Biol. 2007;21:297–302. doi: 10.1111/j.1523-1739.2007.00676.x. [PubMed] [Cross Ref]
41. Hunter Malcolm L. Climate change and moving species: furthering the debate on assisted colonization. Conserv Biol. 2007;21:1356–8. doi: 10.1111/j.1523-1739.2007.00780.x. [PubMed] [Cross Ref]
42. Hoegh-Guldberg O, Hughes L, McIntyre S, Lindenmayer DB, Parmesan C, Possingham HP, Thomas CD. Ecology. Assisted colonization and rapid climate change. Science. 2008;321:345–6. doi: 10.1126/science.1157897. [PubMed] [Cross Ref]
43. Midgley GF, Hughes GO, Thuiller W, Rebelo AG. Migration rate limitations on climate change-induced range shifts in Cape Proteaceae. Diversity Distributions. 2006;12:555–62. doi: 10.1111/j.1366-9516.2006.00273.x. [Cross Ref]
44. Mueller J, Hellmann J. An assessment of invasion risk from assisted migration. Conserv Biol. 2008;22:562–7. doi: 10.1111/j.1523-1739.2008.00952.x. [PubMed] [Cross Ref]
45. Bell G, Collins S. Adaptation, extinction and global change. Evolutionary Applications. 2008;1:3–16. doi: 10.1111/j.1752-4571.2007.00011.x. [PMC free article] [PubMed] [Cross Ref]
46. Araújo MB, Luoto M. The importance of biotic interactions for modelling species distributions under climate change. Global Ecol Biogeogr. 2007;16:743. doi: 10.1111/j.1466-8238.2007.00359.x. [Cross Ref]
47. Morin X, Viner D, Chuine I. Tree species range shifts at a continental scale: new predictive insights from a process-based model. J Ecol. 2008;96:784. doi: 10.1111/j.1365-2745.2008.01369.x. [Cross Ref]
48. Beaumont L, Hughes L, Pitman AJ. Why is the choice of future climate scenarios for species distribution modelling important? Ecol Lett. 2008;11:1135–46. [PubMed]
49. Gunderson LH, Holling CS. Panarchy: Understanding Transformations in Human and Natural Systems. Washington, USA: Island Press; 2002. [Cross Ref]
50. Yohe GW. Representing dynamic uncertainty in climate policy deliberations. Ambio. 2006;35:89–91. doi: 10.1579/0044-7447(2006)35[89:RDUICP]2.0.CO;2. [PubMed] [Cross Ref]
51. Bottrill MC, Joseph LN, Carwardine J, Bode M, Cook C, Game ET, Grantham H, Kark S, Linke S, McDonald-Madden E, Pressey RL, Walker S, Wilson KA, Possingham HP. Is conservation triage just smart decision making? Trends Ecol Evol. 2008;23:649–54. doi: 10.1016/j.tree.2008.07.007. [PubMed] [Cross Ref]

Articles from F1000 Biology Reports are provided here courtesy of Faculty of 1000 Ltd