Contributing Editor Dr. Jordan Schaul and distinguished wildlife biologist and professor Dr. Michael Hutchins discuss the current and anticipated impact of climate change on wildlife species around the globe in an exclusive Nat Geo News Watch interview.
Jordan: In collaboration with the National Wildlife Federation, and Arizona State University scientists, the United States Geological Survey (USGS) recently published a technical report as a contribution to the 2013 Third National Climate Assessment. Entitled the “Impacts of Climate Change on Biodiversity, Ecosystems, and Ecosystem Services,” the report examines changes in the geographic range of species and the timing of significant life history events for these respective animal species. According to the authors, these dramatic developing ecosystem dynamics are mixing species together that have not previously interacted and are creating mismatches between animals and their food sources (http://downloads.usgcrp.gov/NCA/Activities/Biodiversity-Ecosystems-and-Ecosystem-Services-Technical-Input.pdf). Can you elaborate on these points?
Michael: Yes, one of the most pervasive and problematic impacts of climate change on wildlife will be its influence on plant and animal phenology– changes in seasonal life-cycle events like blooming or migrations, that take place as a result of the changing weather patterns (http://www.usanpn.org/about/phenology; Inkly, D., Stault, A., and Duda, M.D. 2009. Imagining the future: Humans, wildlife and global climate change. Pp. 57-72 in Manfredo, M.J. et al. (eds.) Wildlife and Society. Washington, DC: Island Press). Rising temperatures are resulting in earlier springs and longer growing seasons and this has a variety of different environmental influences, including, but not limited to, melting ice packs and glaciers, less snow fall and run-off, changes in the timing of plant and insect emergence, and alterations in animal behavior. A good example is the mistiming of the arrival of migratory birds into temperate regions. Reproduction is generally timed to coincide with an abundance of food; however, if the birds arrive or begin their nesting and breeding cycles too early or too late, sufficient food may not be available to meet the increased energetic demands of reproduction (http://williamrwilson.hubpages.com/hub/Bad-Timing–Global-Warming–and-the-Pied-Flycatcher). The same principle is true of emerging butterflies and moths. If butterflies and moths leave their cocoons too early or too late, that is before or after food or host plants have emerged and bloomed, the mistiming could be fatal or interfere with reproduction (http://blog.stopextinction.org/2009/11/climate-change-will-leave-ediths.html; http://www.sciencedaily.com/releases/2002/05/020515074551.htm). Two winters ago, I had cabbage butterflies flying in my yard in mid-December after a few days of unusually warm weather in the Washington, DC metropolitan area. Warmer temperatures are also impacting migratory behavior and geographic ranges of butterflies, many of which are expanding their ranges into more northern regions (http://www.eje.cz/pdfarticles/1207/eje_104_1_139_Sparks.pdf).
Changes in habitat as a result of changing climatic conditions (wetter, dryer, warmer, colder) will also have significant effects on wildlife and their habitats. Warming temperatures and shorter cold spells, for example, are creating ideal conditions for insect pests, such as bark beetles, which are rapidly changing forest composition (http://www.pnas.org/content/104/50/19697.full). Under a very moderate 2°C warming scenario, for example, the mountain pine beetle is likely to seriously threaten the Rocky Mountain white bark pines, which provide food for many wildlife species (http://www.sciencedaily.com/releases/2012/12/121231161015.htm). Extreme weather, such as high winds, tornados and hurricanes can also cause extensive blow downs, which can subsequently result in rapid changes in forest composition (http://www.redorbit.com/news/science/1890752/staggering_tree_loss_observed_from_2005_amazon_storm/). Climatic changes are gradually replacing some species with others. Northern hardwood forests dominated by silver maple, swamp white oak, and green ash stands are being replaced by oak, pine, and red maple as their ranges shift northward (http://www2.uvm.edu/~wbowden/Teaching/Risk_Assessment/Resources/Public/Projects/Project_docs2009/Riparian_Final_Report_LS_WBB.pdf). Another example is the loss of sugar maple trees, which is affecting the maple syrup industry (http://phys.org/news/2012-11-maple-syrup-moose-local-impacts.html). In areas that are becoming warmer and dryer, the incidence of forest fire is also increasing, thus multiplying risks to wildlife communities (http://theconversation.edu.au/climate-change-fire-may-wipe-out-australias-giant-gum-trees-10491). As you note, rising sea levels from the melting of the polar ice caps and glaciers has the potential to flood low lying islands and coastal areas, thus resulting in a loss of important wildlife habitats (http://obpa-nc.org/DOI-AdminRecord/0053230-0053240.pdf). Disease could also be a problem, as a result of warming temperatures. In particular, disease vectors, such as mosquitos and ticks may become more abundant or emerge earlier than normal, thus increasing the risk of transmission (Kutz, S., Shock, D., Brook, R. and Hoberg, E. 2008. Impending ills: Impacts of climate change on infectious diseases in wildlife. The Wildlife Professional 2(3): 42-46; http://www.wired.com/wiredscience/2012/12/ticks-new-meat/).
Last, but not least, some invasive species could also be favored by climate change, many of which are already significant threats to our native fauna and flora (http://pubs.usgs.gov/of/2006/1153/pdf/of06-1153_508.pdf; http://phys.org/news/2013-01-invading-species-extinguish-native.html). In fact, as I mentioned in our previous interview, climate change may result in our having to redefine the concept of species invasions. Changing environmental conditions may result in a mixing of indigenous species that do not normally co-exist, except perhaps at the periphery of their ranges. This could, among other things, result in increased competition.
Jordan: The polar bear has emerged as an iconic indicator species of climate change, but there are so many other species that the general public is wholly unaware of with regard to climate change and its impact on entire populations of extant fauna. Do you agree? What are some more obscure species that may be affected by climate change and what are some of the cascading effects that these changes will have on ecosystems?
Michael: Absolutely. Polar bears, as an iconic species, have gotten a great deal of attention in the popular media (http://blog.nwf.org/2011/08/polar-bears-and-climate-change-the-science-speaks-for-itself/). However, there are many lesser-known species, particularly those that live in polar or alpine habitats that are being affected by climate change. It is estimated that one tenth of the Western Hemisphere’s mammals may not be able to “outrun” climate change by moving to more suitable habitats (http://www.sciencedaily.com/releases/2012/05/120514153115.htm). Many of these are species that the public may have little awareness of. For example, the American pika, a small lagomorph (related to rabbits) which lives on talus slopes in alpine and subalpine habitats, is being heavily impacted by climate change. Local extinctions have increased ten-fold in the last decade and biologists have observed that the animals are moving to higher elevations as temperatures have increased (http://www.sciencedaily.com/releases/2011/04/110420081826.htm; Beever, E. and Wilkening, L. 2011. Playing by new rules: Altered climates are affecting some pikas dramatically. The Wildlife Professional 5(3): 38-41). Similarly, four subspecies of bearded seals and two populations of ringed seals have recently been listed as threatened or endangered under the Endangered Species Act, primarily due to the impacts of climate change (http://www.sciencedaily.com/releases/2012/12/121230180804.htm). The little-known white lemuroid opossum, a rare marsupial found in northeastern Queensland, may be the first mammalian victim of climate change. The animal has not been sighted in three years, and it is thought to be highly sensitive to temperature change. Just four or five hours of temperatures over 30 degrees could wipe out the highly-vulnerable species, as under extreme heat, they are unable to maintain their body temperature (http://www.telegraph.co.uk/news/worldnews/australiaandthepacific/australia/3544537/Australias-white-possum-could-be-first-victim-of-climate-change.html). Many invertebrates, like butterflies, whose entire life-cycle is impacted by climate change receive little attention (http://www.sciencedaily.com/releases/2012/06/120601120612.htm), yet are essential plant pollinators and food for birds and other animals. Scientists are expecting local extinctions of a third of butterfly species in response to climate change. Even less attention is being given to the smallest of organisms—the plankton at the bottom of the food chains in the world’s oceans or the terrestrial microbes that breakdown dead organisms in terrestrial environments and recycle their bodies back into the earth. Yet, these too are being impacted by climate change (http://www.newscientist.com/article/dn10743-warming-oceans-produce-less-phytoplankton.html; http://environmentalresearchweb.org/cws/article/opinion/37020) The impacts, however, are poorly understood and changing temperatures could produce both positive and negative feedback loops. For example, warming is predicted to increase rates of decomposition in northern latitudes, which could have pervasive effects on nutrient cycles. That being said, these organisms can also be carbon sinks, which could help to sequester atmospheric carbon (http://www.redorbit.com/news/technology/1488638/plankton_changes_atlantic_into_carbon_sink/).
Jordan: Certainly some species impacted by climate change will influence a cascade of events impacting ecosystems, which may include further decimation of wildlife populations. These effects on population sizes may be even more dramatic than we see in Polar Regions because of disparities in biodiversity in polar, temperate and tropical regions of the world. Can you elaborate on this concern?
Michael: Yes, this is a legitimate concern. As we know from basic ecology, organisms in functioning ecosystems are interdependent and linked together in complex webs. The loss of one species can therefore result in a cascade of extinctions. Well known biologists Paul and Anne Ehrlich once liked this to taking the bolts out of a flying aircraft one at a time. It may hold together for a while, but eventually, a wing will fall off and the entire plane will crash (Ehrlich, P. and Ehrlich, A. 1981. Extinction: The Causes and Consequences of the Disappearance of Species. New York: Random House). This is especially true for so-called keystone species that are at the center of these complex relationships. To the extent that climate change results in species extinctions—either directly or indirectly—we are likely to see such extinction cascades occur, and this could result in a significant loss of biodiversity.
Jordan: While working with endangered wood bison in Alaska in an effort to reintroduce this northern subspecies of American bison—the largest terrestrial mammal in the Western Hemisphere—to the Frontier State, we argued that the return of the extirpated bovid to its historic range in Alaska would serve the interests of climate change mitigation. Bringing back bison, should not only complete the faunal assemblage of herbivores in the region, through the reintroduction of a keynote grazing ungulate, but it represents (offers) an opportunity to restore habitat to a state conducive to promoting biodiversity, as bison wallows provide microhabitats attractive to array of aquatic and terrestrial wildlife and plant species According to the Convention on Biological Diversity, an increase in biodiversity stifles climate change (or promotes climate change mitigation and adaptation). Can you explain this notion or provide some additional examples of how conserving and adequately managing biodiversity assists with climate change mitigation? What are the relationships among climate change mitigation, biodiversity and land degradation?
Michael: There is no doubt that maintaining biological diversity should be a major goal in climate change mitigation. Diversity contributes to the resilience of an ecosystem to perturbations and disturbance. Furthermore, ecosystems and their biodiversity have important roles to play in sequestering carbon (http://www.sciencedaily.com/releases/2008/12/081205153515.htm; http://takvera.blogspot.com.au/2012/05/seagrass-meadows-are-key-carbon-sinks.html). Informed decision-making and careful management of natural ecosystems for mitigation can enhance this role and help to avoid potential negative impacts. As climate change increasingly puts a strain on ecosystems and their animal and plant populations, it is important to find ways to increase their resilience to current and future climate change. In addition, some species, may be able to adapt rapidly to climate change through natural selection (http://bio.research.ucsc.edu/~barrylab/classes/climate_change/Hoffmann_Sgro_nature_2011_adaptation.pdf ; http://www.plantphysiol.org/content/160/4/1728.full ), or through changes in phenology (http://onlinelibrary.wiley.com/doi/10.1111/j.1461-0248.2012.01765.x/abstract).
Jordan: Catastrophic weather patterns are among the stochastic events that impact wildlife populations. El Nino events reported in the Pacific come to mind. These isolated events can wipe out conservation sensitive populations of wildlife and particularly those at higher trophic levels like pinnipeds and cetaceans. How are these events different from what climate scientists refer to as global warming and what may be the difference with regard to their impact on wildlife populations?
Michael: Like tsunamis and volcanic eruptions, catastrophic weather events, such as hurricanes, tornados, flash freezes and ice storms, extreme drought, and flooding, can have devastating effects on wildlife populations and on the plant communities that sustain them. This is particularly true of small, isolated populations of conservation concern. The smaller and less distributed a species is, the higher the risk that a single weather event could push it over the brink of extinction. These isolated events are different from global warming (which refers to the recent rise in average global air and water temperatures), but the increasing intensity and frequency of such events is consistent with what is expected from a warming planet (http://content.usatoday.com/communities/sciencefair/post/2011/09/climate-report-links-2011-extreme-weather-events-to-global-warming/1 ; http://climatecommunication.org/new/articles/extreme-weather/overview/).
Jordan: What is climate change adaptation? What can wildlife managers and conservationists do to promote climate change mitigation?
Michael: People should not confuse the term “climate change adaptation” with “adaptation” as it is normally used in evolutionary biology. In the latter, adaptation is used to denote genetic, physiological, and anatomical changes in species as they better adapt themselves to changing environmental circumstances through the process of natural selection (differential survival and reproduction). However, climate change adaptation refers to how we (humans) as stewards of our planet are going to respond to climate change in order to conserve as much biodiversity as possible. At this point, some climate change is inevitable. However, there is a difference between adaptation and mitigation. The severity of change could be mitigated by humans. Chief among these responses would be a massive shift from fossil fuels to renewable energy, which could reduce carbon dioxide and other greenhouse gases in our atmosphere (http://www.livescience.com/25911-politics-climate-change-mitigation.html). Although the causes of climate change are complex, there is a direct correlation between the rise of greenhouse gases in our atmosphere since the industrial revolution and a warming planet (http://www.epa.gov/climatechange/science/causes.html). So, there is some hope that we might head off the worst of impacts with a concerted effort at mitigation. However, some would argue that we already have enough greenhouse gases in our atmosphere to give us another 100 years or more of climate change (http://www.cnn.com/2007/TECH/science/07/18/last.generation/; http://www.businessinsider.com/its-probably-too-late-to-roll-back-global-warming-2012-12).
Rushing to clean energy is also a potential problem, as wind, solar and other alternative energy sources can harm wildlife (Hutchins, M. and Bies, L. 2010. How green is “green” energy. Outdoor America Winter: 16-17; Leitner, P. 2009. The promise and peril of solar power. The Wildlife Professional 3(1): 48-53). Such facilities should not be sited in sensitive ecological areas or, in the case of wind, in areas with large bird or bat concentrations. We clearly need cleaner sources of energy, but it would be counterproductive if such alternatives were also bad for our native wildlife and their habitats.
While serving as Executive Director/CEO of the Wildlife Society, I was very active in trying to identify solutions. In 2011, I participated in a series of leadership forums organized by the U.S. Fish and Wildlife Service at the National Conservation Training Center in Shepherdstown, WV. These meetings initiated the development of a national climate adaptation strategy for fish, wildlife and plants (http://www.wildlifeadaptationstrategy.gov/steering-committee.php). There are many things that could potentially be done to mitigate the impact of climate change on biodiversity, including the acquisition of new conservation lands to replace those lost to rising sea levels and habitat change, to create corridors to facilitate the movement of wildlife and plants, active management of current habitats and native species to promote ecosystem resilience to climate-induced stress, and the creation of new protected areas (Abhat, D. and Unger, K. 2008. Reining in the impacts of climate change. The Wildlife Professional 2(3): 33-38).
In ecology, resilience is the capacity of an ecosystem to respond to a perturbation or disturbance by resisting damage and recovering quickly. There is some question as to whether such factors can actually be managed and some scientists have therefore argued that we should plan for recovery rather than resilience (http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1000438). In addition, some have argued that our current system of static protected areas will not be as useful for conservation in the face of a changing climate (Hall, H.D. and Ashe, D.M. 2008. Changing as conditions change. The Wildlife Professional 2(3): 11-13). For example, under climate change, a protected area established to conserve a particular species may no longer offer the conditions necessary for its survival, or species may move out of protected areas seeking more favorable conditions (e.g. as in the case of vertical migration; http://www.sciencedaily.com/releases/2011/12/111208121028.htm). Indeed, some protected areas, such as those in coastal areas, may disappear altogether, thus making the current extinction crisis even more intense. Others have argued that protected areas will be important insurance against extinction (http://www.sciencedaily.com/releases/2012/08/120813155243.htm). However, to fulfill this role, protected areas will need to be in locations that are predicted to escape the brunt of climate change, and they will need to be linked, rather than isolated. Without a strategically distributed network of protected areas, biomes of the future will likely be limited to weedy and disturbance-tolerant generalist species that might not preserve ecosystem function and services.
In order to help with this kind of landscape level planning, the U.S. Fish and Wildlife Service developed the concept of Landscape Conservation Cooperatives or LCCs (http://www.fws.gov/landscape-conservation/lcc.html; Austen, D.J. 2011. Landscape Conservation Cooperatives: A science-based network in support of conservation. The Wildlife Professional 5(3): 32-37.). These are regionally ecosystem-based cooperatives consisting of representatives from federal and state government agencies, conservation organizations, and academia. Such public-private partnerships are intended to provide the necessary expertise and partnerships to plan for ecosystem resiliency and recovery in the face of climate change and other environmental stressors. It is hoped that through careful planning and management that resiliency can be increased and adaptation to climate change accelerated (http://onlinelibrary.wiley.com/doi/10.1111/j.1523-1739.2012.01954.x/abstract; http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2791483/; http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3410031/). Of course, in order to plan for future climate adaptation, one needs some basis for predicting the impacts on climate change on specific locations and communities. Much work is currently being done to translate general weather models to a scale that will be useful for managers and to try to deal with the uncertainty inherent in such models (http://www.sciencedaily.com/releases/2010/08/100805111234.htm ; http://www.gbif.es/ficheros/Taller_nichos_10/Pearson_Dawson_2003_GEB_Are%20bioclimate%20envelope%20models%20useful.pdf; http://www.clas.ufl.edu/users/mbinford/GEOXXXX_Biogeography/LiteratureForLinks/iverson_and_prasad_1998_predicting_abundance_80_tree_species_climate_change_EUS_EcolMonogr.pdf ). In order to facilitate and promote the science behind such predictions, the U.S. Geological Survey has developed a National Climate Change and Wildlife Science Center (https://nccwsc.usgs.gov/). This is being further augmented by the Department of the Interior’s Climate Science Centers (http://www.doi.gov/csc/index.cfm). In 2010 and 2011, I helped to organize a series of meetings that led to the creation of these centers at the request of USGS (http://www.esa.org/science_resources/DocumentFiles/TWS-ClimChgReportFINAL.pdf; https://nccwsc.usgs.gov/sites/default/files/documents/other/NPD%20Report%20FINAL.pdf).
In a changing climate, monitoring and better understanding the effects of such changes also becomes crucial, and much more of this will have to be done in the future (Beard, T.D, O’Malley, R., and Robertson, J. 2011. New research on climate’s front line: Understanding climate change impacts on fish and wildlife. The Wildlife Professional 5(3): 26-30. The National Climate Change and Wildlife Science Center and DOI Climate Science Centers should play an increasingly important role in monitoring, as should the LCCs. However, citizen science is also very useful in this regard and many lay people now volunteer their time to assist in these monitoring processes. One program I’ve been closely involved with is the USA National Phenology Network (USA-NPN), a program that uses citizen and professional scientists to monitor biological phenomena associated with climate change (http://www.usanpn.org). The NPN has long maintained a system of monitoring plant phenology, but more recently, they have developed methods for monitoring wildlife as well (Miller-Rushing, A.J. 2010. Wildlife watchers aid climate research. The Wildlife Professional 4(2): 58-61). Check out their website and their “Nature’s Notebook” Program to see how you can get involved in tracking the effects of climate change on plants and animals in your own backyard (http://www-dev.usanpn.org/how-observe).
A key question going forward will be how to better integrate research with management. Often there has been a rift between university or agency scientists who are seeking to understand natural phenomena and resource managers (Sands, J.P. et al. (eds) Wildlife Science: Connecting Research with Management. New York: CRC Press). The former are interested in knowledge for knowledge’s sake and the latter in how that basic research will be applied to real life problems. In the past, communication between scientists and managers has been poor or non-existent and that must change. Managers must do a better job communicating their informational needs to scientists, scientists must do a better job of translating their findings for managers, and cooperative planning for adaptation will be critical. If this can be accomplished, then the results of research can be more immediately applied to key resource management challenges associated with climate change.
It is promising that the infrastructure described above has been or is being developed to help our nation address climate change mitigation. However, implementation is going to be expensive, and given our current economic situation, it is questionable whether the funds will be available. One of the most significant questions for conservation in coming years is how we will pay for it? (Hutchins, M. 2012. What the future holds? The Wildlife Professional 6(3): 83-87; Hutchins, M., Eves, H., and Mittermeier, C.G. 2009. Fueling the conservation engine: Where will the money come from to drive fish and wildlife management and conservation? Pp.184-197 in Manfredo, M.J. et al. (eds.) Wildlife and Society. Washington, DC: Island Press). One way that this could be done would be to tax carbon emissions, but this solution has been highly controversial and no action has yet been taken (http://www.washingtonpost.com/opinions/the-carbon-tax/2012/11/10/6c576bfa-29f5-11e2-b4e0-346287b7e56c_story.html).
Jordan: Is choosing to protect our natural wildlife heritage for its intrinsic or fundamental value or for the resource value they provide us going to dictate how we develop or implement strategies aimed at promoting climate change mitigation and adaptation?
Michael: This is an interesting question. Climate change represents one of the most significant challenges humankind has ever faced, and, as we go forward, there are many ethical and practical questions that will need to be answered. Wildlife managers and conservationists are acknowledging that some species are going to be lost, and like it or not, we may need to resort to a triage-like decision-making process to decide which species we will focus our attention on and which we will not (http://www.eurekalert.org/pub_releases/2011-11/w-cs110711.php). But, how we will make such decisions and on what basis? As one example, fisheries managers are concerned about the future survival of native western trout as a result of climate change, but they doubt that all varieties can be saved and have suggested that a triage approach might save some (http://thinkprogress.org/climate/2012/12/20/1362371/fish-fry-study-says-climate-change-means-tough-going-for-western-trout/). Furthermore, some groups of animals are likely to be more susceptible to climate change than others (http://www.sciencedaily.com/releases/2008/10/081013142545.htm). Should we focus more attention on particularly vulnerable species or should we write them off and focus our limited resources on those that have a higher probability of survival? The future of life on our planet will depend on how such difficult and complex questions are resolved.