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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.
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Climate change: A threat for the Andean bear? Shaenandhoa García-Rangel Juan Papadakis Edgard Yerena Departamento de EstudiosAmbientales, Universidad Simón Bolívar Venezuela 20th International Conference on Bear Research and Management, Ottawa – Canada 2011
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 context • THE 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) 1986 2007 Cotopaxi Glacier, Ecuador 30% decrease 1956-1976 38.5% decrease 1976-2006 (UNEP, Cathalac;Vergara 2007)
The Latin-American context • THE 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 context • THE 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) Reduction of water supplies for food production and urban areas Limitations in hydroelectric power generation Highest concentration of human population High deforestation rates (Palminteri et al. 2001, Vergara 2007)
The Latin-American context VULNERABLE
Climate change – Andean-bear project THE 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 project • OBJECTIVES • 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 project • METHODS • Species Distribution Models (SDMs) for different scenarios • Changes in Andean-bear habitat suitability • 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 project • METHODS • Species presence data (1844 ~ 2004): 544 records.
Climate change – Andean-bear project • METHODS • Species presence data (1844 ~ 2004): 544 records. (ArcGIS 9.3) • Independent variables • WorldClim(http://www.worldclim.org/) • Averageconditions: Today • Model: CCCMA, scenario B2. Year = 2050 • (Flato et al. 2000) Temp. max and min. Precipitation Elevation
Climate change – Andean-bear project • METHODS • WorldClim(http://www.worldclim.org/) • Model: CCCMA, scenarioB2. Year = 2050 (Flato et al. 2000)
Climate change – Andean-bear project • METHODS • Species presence data (1844 ~ 2004): 544 records. • Independent variables • WorldClim(http://www.worldclim.org/) • Averageconditions: 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) • Foodresourcesaccordingto Figueroa and Stucchi (2009) Temp. max and min. Precipitation Elevation Families: 5 Genera: ~10 Species: 18
Climate change – Andean-bear project • METHODS • Species presence data (1844 ~ 2004): 544 records. • Independent variables • SDMs ArcGIS 9.3 • Maximum Entropy Method (Phillips et al. 2006) • Scale: 30 arc-seconds (~1 km). MaxentVersión 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.
Climate change – Andean-bear project • RESULTS
Climate change – Andean-bear project • RESULTS • Model: Climate Model: Climate + Food resources Today Future Today Future
Climate change – Andean-bear project • RESULTS • Food resources are important modulators of Andean-bear’s habitat suitability. • Model: Climate + Food Resources • Today Future • Variable contribution: 42.8% Variable contribution: 36.8%
Climate change – Andean-bear project • RESULTS • Today 2050
Climate change – Andean-bear project • RESULTS • Today 2050
Climate change – Andean-bear project • DISCUSSION • DISCUSSION • 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. • 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.
Climate change – Andean-bear project • DISCUSSION • 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? • To increase coverage and time-span of Andean-bear present points. • To explore differential weighting of food resources and the inclusion of other species. • To incorporate land-cover change projections. • To evaluate prediction behavior with CSIRO and HADCM3 climatic models and other scenarios available. • To evaluate the role of protected areas to secure Andean-bear habitat.
Acknowledgements Universidad Simón Bolívar • 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.
Climate change – Andean-bear project • RESULTS