Current & Future Ecological Responses to Climate Change

Current & Future Ecological Responses to Climate Change Dr. Heather Throop NMSU Biology 2090-2099 IPCC, 2007

Climatology is easy… Complexities of understanding biological responses interactions between organisms short vs. long term patterns extremes, not averages, may be important 2090-2099 IPCC, 2007

Climate Change Does Not Occur in a Vacuum • Increasing urbanization and sprawl • Landscape fragmentation • Air & water pollution • Elevated atmospheric CO2

Ways to Study Ecological Impacts • Observations • Manipulative experiments • Computer simulations Natural Environment Research Council, UK

4th Assessment Report -- 2007 • Consensus report • >1200 authors • >2500 expert reviewers • >130 countries

There is medium confidence that approximately 20-30% of species assessed so far are likely to be at increased risk of extinction if increases in global average warming exceed 1.5-2.5ºC (relative to 1980-1999). As global average temperature exceeds about 3.5ºC, model projections suggest significant extinctions (40-70% of species assessed) around the globe. IPCC, SPM 2007

Biological Impacts • Physiology • Phenology (timing) • Community composition & disease • Range shifts

Biological Impacts • Physiology • Phenology (timing) • Community composition & disease • Range shifts EXTINCTIONS

Phenology • Timing of a biological activity • Examples: • Spring leaf-out • Fall leaf drop • Migratory bird arrival

Earlier Spring Events • Documented Shifts Earlier: • Flowering & leafing, Europe & N. America (1 - 3 days earlier/decade) • Butterfly breeding, UK • Amphibian breeding, UK • Bird migration & breeding, Europe & N. America

Summary of spring phenology: 61 studies, 694 species, past 50 years Root et al. (2003) Nature

Pied Flycatcher, The Netherlands Mismatch between timing of hatching & food abundance  population declines Early caterpillar peak Late caterpillar peak Both et al. (2006) Nature

Later Fall Events? • Less clear than spring • Delay of leaf color changes in Europe

Community Composition • Climate changes may affect species differentially • Changes in abundance of one species (including pathogens) may affect other species

Southern Switzerland Walther et al. 2002 Nature

Climate change likely to increase severity/frequency of disease outbreaks  population declines & extinctions Protozoan on monarchs Fungus - sea fans Distemper outbreak - lions Fungus - leaves C. D. Harvell et al. (2002) Science

Hawai’i ~60 of 100 endemic bird species currently extinct Harvell et al. (2002) Science Benning et al. (2002) Proc. Natl. Acad. Sci.

Coral Bleaching • Corals highly vulnerable to thermal stress • 1-3ºC sea surface temperature increases: frequent bleaching, widespread mortality Photos: Wikipedia.org

Range Shifts • Climate changes affect species range • Changes in • Latitude (towards poles) • Elevation

Range Shifts • Summary including >1,700 species: • recent biological trends match climate change predictions • range shifts average: • 6.1 km/decade toward the poles • OR 6.1 m/decade upward Parmesan & Yohe (2003) Nature

Other Range Shifts • Treeline: Europe & New Zealand • Arctic & alpine plants: Alps, Alaska • 1-4 m/decade • Birds in Britain • 19 km N in 20 years • Foxes, Canada

Can we count on range shifts as a “solution”?

“ I hope I have justified the conviction, shared by many thoughtful people from all walks of life, that the problem can be solved. Adequate resources exist. Those who control them have many reasons to achieve that goal, not least their own security. In the end, however, success or failure will come down to an ethical decision, one on which those now living will be defined and judged for all generations to come.” E.O. Wilson (2001) The Future of Life

Current & Future Ecological Responses to Climate Change