shaenandhoa garcía-rangel juan papadakis edgard yerena
DESCRIPTION
Climate change: A threat for the Andean bear?. Shaenandhoa García-Rangel Juan Papadakis Edgard Yerena Departamento de Estudios Ambientales , Universidad Simón Bolívar Venezuela 20 th International Conference on Bear Research and Management, Ottawa – Canada 2011. Topics. - PowerPoint PPT PresentationTRANSCRIPT
Shaenandhoa García-Rangel Juan Papadakis Edgard Yerena
Departamento de Estudios Ambientales, Universidad Simón BolívarVenezuela
20th International Conference on Bear Research and Management, Ottawa – Canada 2011
Climate change:A threat for the Andean bear?
Topics• The Latin-American context to global warming.
• The Andes mountain range
• The Andean bear
• Climate change – Andean-bear project • Objectives
• Methods
• Preliminary results
• Limitations and future directions
The Latin-American context In Latin America, climate impacts are very significant and expected to irreversibly affect key ecosystems and the services these provide. (Vergara 2007)
• In 2005, over 80% of coral reefs across the Caribbean basin suffered bleaching as a consequence of heat stress.
• Risk of coastal flooding and salinization.• Increase in sea-level rise across the South Atlantic Coast.
• Hurricanes trends have intensified. • Costs of impacts > 2 times since 1970.• 4 of 10 most active years have been recorded since 1997.
• Changes in precipitation and temperature patterns. • Amazonian drought of 2005 and the prospect of Amazonian dieback. Critical role in precipitation patterns across South America.
(GEOLAC 2010, Vergara, 2007)
The Latin-American context
Human-pop. growth > mean
Exploitation of natural resources
Total GHG contribution: 11.78%
Net forest loss > 0.5% yearly
(Eclac, 2009, Geolac 2010, FAO 2005 )
The Latin-American contextTHE ANDES MOUNTAIN RANGE
• Global circulation models
• Rapid Glacier Retreat• Troposphere warming• Shift in the freezing point isotherm
Temperature increases > lowlands
Change the ecology of the Andes (Vergara, 2007)
Cotopaxi Glacier, Ecuador30% decrease 1956-1976
38.5% decrease 1976-2006
(UNEP, Cathalac;Vergara 2007)
1986 2007
The Latin-American contextTHE ANDES MOUNTAIN RANGE
• Global circulation models
• Rapid Glacier Retreat• Troposphere warming.• Shift in the freezing point isotherm.
• Vulnerability of high-mountain ecosystems• Water cycle disruptions .• Disappearance of high-altitude water bodies.• Increase occurrence of fires.
Temperature increases > lowlands
Change the ecology of the Andes (Vergara, 2007)
(Palminteri et al. 2001, Vergara 2007)
The Latin-American contextTHE ANDES MOUNTAIN RANGE
• Global circulation models
• Rapid Glacier Retreat
• Vulnerability of high-mountain ecosystems
Temperature increases > lowlands
Change the ecology of the Andes (Vergara, 2007)
(Palminteri et al. 2001, Vergara 2007)
Reduction of water supplies for food production and urban areas
Limitations in hydroelectric power generation
Highest concentration of human population
High deforestation rates
The Latin-American context
VULNERABLE
Climate change – Andean-bear projectTHE ANDEAN BEAR
VULNERABLE (Goldstein et al. 2008)
Carnivore in SA moving faster towards extinction (Cardillo et al. 2004)
Population trends
Habitat loss 2-4% a year
High levels of fragmentation (Goldstein et al. 2008)
Climate change – Andean-bear projectOBJECTIVES
• To evaluate the impact of global warming on the Andean bear across the Northern Andes.
• To compare the impact of global warming and land-cover change on the Andean bear across the Northern Andes.
• To evaluate the role of protected areas to secure Andean-bear habitat in the future.
PRELIMINARY RESULTS
ANALYSIS LIMITATIONS
FUTHER QUESTIONS RISEN (Rodriguez et al. 2003)
Climate change – Andean-bear projectMETHODS
Species Distribution Models (SDMs) for different scenarios
Changes in Andean-bear habitat suitability
1)Species presence data (1844 ~ 2004): 544 records.
• GBIF (http://data.gbif.org/welcome.htm): 33 records.
• Yerena (1994): 108 records.
• Sánchez-Mercado (2008): 404 records.
Climate change – Andean-bear projectMETHODS
1)Species presence data (1844 ~ 2004): 544 records.
METHODS
1)Species presence data (1844 ~ 2004): 544 records. (ArcGIS 9.3)
2) Independent variables
• WorldClim (http://www.worldclim.org/)
• Average conditions: Today
• Model: CCCMA, scenario B2. Year = 2050 (Flato et al. 2000)
Climate change – Andean-bear project
Temp. max and min.
Precipitation
Elevation
METHODS
• WorldClim (http://www.worldclim.org/)
• Model: CCCMA, scenario B2. Year = 2050 (Flato et al. 2000)
Climate change – Andean-bear project
METHODS
1)Species presence data (1844 ~ 2004): 544 records.
2) Independent variables
• WorldClim (http://www.worldclim.org/)
• Average conditions: Today
• Model: CCCMA, scenario B2. Year = 2050 (Flato et al. 2000)
• DMSP-OLS Nighttime Lights Time Series V.4. •1992 and 2009 models. http://www.ngdc.noaa.gov/dmsp/download.html)
• GBIF (http://data.gbif.org/welcome.htm)• Food resources according to Figueroa and Stucchi (2009)
Climate change – Andean-bear project
Temp. max and min.
Precipitation
Elevation
Families: 5
Genera: ~10
Species: 18
METHODS
1)Species presence data (1844 ~ 2004): 544 records.
2) Independent variables
3)SDMs
Climate change – Andean-bear project
Maximum Entropy Method (Phillips et al. 2006)
• Scale: 30 arc-seconds (~1 km). Maxent Versión 3.3.3e, HPTQ.
Jack-knifing procedure for variable importance.
AUC measure for model evaluation. 15% testing dataset.
“Maximum test sensitivity plus specificity” threshold for output.
ArcGIS 9.3
RESULTS
Climate change – Andean-bear project
RESULTS Model: Climate Model: Climate + Food resources
Climate change – Andean-bear project
Today
Future
Today
Future
RESULTS
Food resources are important modulators of Andean-bear’s habitat suitability.
Model: Climate + Food Resources
Today FutureVariable contribution: 42.8% Variable contribution:
36.8%
Climate change – Andean-bear project
RESULTS
Today 2050
Climate change – Andean-bear project
Climate change – Andean-bear projectRESULTS Today 2050
DISCUSSION
Climate change – Andean-bear projectDISCUSSION
3.Preliminary results show that climate change do not seem to pose a major threat to Andean bears in the middle-term (2050).
• Land-cover change and human-population growth are known threats to the species, and so they must be incorporated in any assessment regarding climate change.
4. Models show potential Andean-bear habitat suitability.
• Areas are considerably overestimated but relative variations could be indicators of future scenarios.
• No historic barriers or restriction due to human developments are incorporated.
• We require information on land-cover change to be able to draw guidelines for conservation.
DISCUSSION
3. Changes in the distribution of food resources could open new spaces to the Andean bear.
• Species overlap remains within the Northern Andes. •Andean bears are constrain to the limits of the Northern Andes by some unidentified factor (Temperature?, food resources?).
Climate change – Andean-bear project
WHAT’S NEXT?
1. To increase coverage and time-span of Andean-bear present points.
2. To explore differential weighting of food resources and the inclusion of other species.
3. To incorporate land-cover change projections.
4. To evaluate prediction behavior with CSIRO and HADCM3 climatic models and other scenarios available.
5. To evaluate the role of protected areas to secure Andean-bear habitat.
Climate change – Andean-bear project
• Dr Chris Servheen.
• Dr Martyn Obbard.
• Dr Ada Sánchez-Mercado.
• Érika Pedraza.
• Bear Specialist Group.
• Laboratorio de Sensores Remotos y Análisis Geoespacial.
• ESRI Conservation Program.
Acknowledgements
Universidad Simón Bolívar
Thank you!
RESULTS
Climate change – Andean-bear project
Climate change – Andean-bear project