Publications Published in Conservation Biology

1. Can Large-Scale Climatic Models Be Linked with Multiscale Ecological Studies?. Root, Terry L.; Schneider, Stephen H..
   Conservation Biology: 1993
   Notes
   On a global scale, climatic changes driven by human activities are typically projected to increase from 1°C to 5°C per 100 years, a rate of change that is an order of magnitude greater than that typically experienced naturally. Such a potentially dramatic change in climate could easliy cause dramati biological responses, including extinction. Species show a wide range of responses to climate, and consequently the response of different species of plants and animals to climatic change will be quite variable. This implies a likelihood for a disassembling of natural communities and for transient, nonequilibrium restructuring of habitats as climatic change unfolds. Validated models that help forecast these events are needed to aid scientists in better understanding the ecological ramifications of global climatic change. Also, and perhaps more important for conservation biology, such validated models can help provide probabilities for the occurrence of these events, which will allow policy makers to make better, informed decisions. Typically, the study plots of most ecological field work are tennis-court-sized, while the smalles resolved scales in global climatic models are about 500 X 500 km. Computer limitations preclude significant reduction in scales of climatic models.
   
   
   
2. Climate Change, Elevational Range Shifts, and Bird Extinctions. Sekercioglu, Cagan H.; Schneider, Stephen H.; Fay, John P.; Loarie, Scott R..
   Conservation Biology: 2008
   DOI: doi:10.1111/j.1523-1739.2007.00852.x
   Notes
   Limitations imposed on species ranges by the climatic, ecological, and physiological effects of elevation are important determinants of extinction risk. We modeled the effects of elevational limits on the extinction risk of landbirds, 87% of all bird species. Elevational limitation of range size explained 97% of the variation in the probability of being in a World Conservation Union category of extinction risk. Our model that combined elevational ranges, four Millennium Assessment habitat-loss scenarios, and an intermediate estimate of surface warming of 2.8o C, projected a best guess of 400-550 landbird extinctions, and that approximately 2150 additional species would be at risk of extinction by 2100. For Western Hemisphere landbirds, intermediate extinction estimates based on climate-induced changes in actual distributions ranged from 1.3% (1.1o C warming) to 30.0% (6.4o C warming) of these species. Worldwide, every degree of warming projected a nonlinear increase in bird extinctions of about 100-500 species. Only 21% of the species predicted to become extinct in our scenarios are currently considered threatened with extinction. Different habitat-loss and surface-warming scenarios predicted substantially different futures for landbird species. To improve the precision of climate-induced extinction estimates, there is an urgent need for high-resolution measurements of shifts in the elevational ranges of species. Given the accelerating influence of climate change on species distributions and conservation, using elevational limits in a tested, standardized, and robust manner can improve conservation assessments of terrestrial species and will help identify species that are most vulnerable to global climate change. Our climate-induced extinction estimates are broadly similar to those of bird species at risk from other factors, but these estimates largely involve different sets of species. Cambio Climatico, Desplazamiento de Rangos Altitudinales y Extinciones de Aves Resumen: Las limitaciones en la distribucion de especies impuestas por los efectos climaticos, ecologicos y fisiologicos de la altitud son determinantes importantes del riesgo de extincion. Modelamos los efectos de los limites altitudinales sobre el riesgo de extincion de aves terrestres, 87% del total de especies de aves. La limitacion altitudinal del rango de distribucion explico 97% de la variacion en la probabilidad de estar en una categoria de riesgo de extincion de la Union Mundial para la Conservacion (IUCN). Mediante un modelo que combino limitaciones altitudinales, escenarios de perdida de habitat de la Evaluacion 4 Milenio y una estimacion intermedia de calentamiento superficial de 2.8o C, se estimaron entre 400 y 550 extinciones de aves terrestres y que aproximadamente 2500 especies adicionales estarian en riesgo de extincion en 2100. Para aves terrestres del Hemisferio Occidental, las estimaciones de extinciones intermedias basadas en cambios inducidos por el clima en las distribuciones actuales variaron entre 1.3% (calentamiento: 1.1o C) y 30.0% (calentamiento: 6.4o C) de estas especies. A nivel mundial, cada grado de calentamiento proyecto un incremento no lineal en las extinciones de 100 a 500 especies. Solo 21% de las especies cuya extincion se pronostico en nuestros escenarios estan consideradas como amenazadas de extincion actualmente. Escenarios diferentes de perdida de habitat y de calentamiento superficial pronosticaron futuros sustancialmente diferentes para las especies de aves terrestres. Para mejorar la precision de las estimaciones de extinciones inducidas por el clima, hay una urgente necesidad de medidas de alta resolucion de los desplazamientos de los rangos altitudinales de las especies. Dada la acelerada influencia del cambio climatico sobre la distribucion y conservacion de especies, el uso de limites altitudinales en una forma probada, estandarizada y robusta puede mejorar las evaluaciones de conservacion de especies terrestres y ayudara a identificar especies que son mas vulnerables al cambio climatico global. Nues ras estimaciones de extinciones inducidas por el clima son similares a las de especies en riesgo por otros factores, y principalmente involucran diferentes conjuntos de especies.
   
   
   
3. Conservation and Adaptation to Climate Change. Brooke, C..
   Conservation Biology: 2008
   DOI: 10.1111/j.1523-1739.2008.01031.x
   Notes
   The need to adapt to climate change has become increasingly apparent, and many believe the practice of biodiversity conservation will need to alter to face this challenge. Conservation organizations are eager to determine how they should adapt their practices to climate change. This involves asking the fundamental question of what adaptation to climate change means. Most studies on climate change and conservation, if they consider adaptation at all, assume it is equivalent to the ability of species to adapt naturally to climate change as stated in Article 2 of the United Nations Framework Convention on Climate Change. Adaptation, however, can refer to an array of activities that range from natural adaptation, at one end of the spectrum, to sustainability science in coupled human and natural systems at the other. Most conservation organizations deal with complex systems in which adaptation to climate change involves making decisions on priorities for biodiversity conservation in the face of dynamic risks and involving the public in these decisions. Discursive methods such as analytic deliberation are useful for integrating scientific knowledge with public perceptions and values, particularly when large uncertainties and risks are involved. The use of scenarios in conservation planning is a useful way to build shared understanding at the science-policy interface. Similarly, boundary organizations-organizations or institutions that bridge different scales or mediate the relationship between science and policy-could prove useful for managing the transdisciplinary nature of adaptation to climate change, providing communication and brokerage services and helping to build adaptive capacity. The fact that some nongovernmental organizations (NGOs) are active across the areas of science, policy, and practice makes them well placed to fulfill this role in integrated assessments of biodiversity conservation and adaptation to climate change.La necesidad de adaptarse al cambio climatico es cada vez mas aparente, y muchos creen que la practica de la conservacion de la biodiversidad tendra que alterarse para enfrentar este reto. Las organizaciones de conservacion tienen interes en determinar como deben adaptar sus practicas al cambio climatico. Esto implica responder la pregunta fundamental de lo que significa adaptacion al cambio climatico. La mayoria de los estudios sobre cambio climatico y conservacion, si acaso consideran la adaptacion, asumen que es equivalente a la habilidad de las especies a adaptarse naturalmente al cambio climatico en los terminos del Articulo 2 de la Convencion del Cambio Climatico de las Naciones Unidas. Sin embargo, adaptacion se puede referir a un conjunto de actividades que varian entre la adaptacion natural en un extremo del espectro, y ciencia de la sustentabilidad en sistemas naturales y humanos en el otro. La mayoria de las organizaciones de conservacion tratan con sistemas complejos en los que la adaptacion al cambio climatico implica la toma de decisiones sobre prioridades para la conservacion de la biodiversidad frente a riesgos dinamicos y el involucramiento del publico en estas decisiones. Los metodos discursivos como la deliberacion analitica son utiles para la integracion de conocimiento cientifico con las percepciones y valores del publico, particularmente cuando implican grandes riesgos e incertidumbres. El uso de escenarios en la planificacion de la conservacion es una forma util para construir el entendimiento de la interfase ciencia-politica. Similarmente, las organizaciones frontera - organizaciones o istituciones que unen escalas diferentes o que median la relacion entre la ciencia y la politica - podrian ser utiles para el manejo de la naturaleza transdisciplinaria de la adaptacion al cambio climatico, para proporcionar servicios de comunicacion y correduria y para ayudar a construir capacidad adaptativa. El hecho de que algunas organizaciones no gubernamentales (ONG) son activas en las areas de la ciencia, la politica y la practica las posiciona para desempenar este papel en evaluaciones integrales de conservacion de la biodiversidad y adaptacion al cambio climatico.
   
   
   
4. Conservation of Biodiversity in a Changing Climate. Hannah, L.; Midgley, G. F.; Lovejoy, T.; Bond, W. J.; Bush, M.; Lovett, J. C.; Scott, D.; Woodward, F. I..
   Conservation Biology: 2002
   DOI: doi:10.1046/j.1523-1739.2002.00465.x
   
   
5. Contributed Papers Effects of Climate Change on Population Persistence of Desert-Dwelling Mountain Sheep in California.. Epps, Clinton W.; McCullough, Dale R.; Wehausen, John D.; Bleich, Vernon C.; Rechel, Jennifer L..
   Blackwell Publishing Limited Conservation Biology: 2004
   Notes
   Metapopulations may be very sensitive to global climate change, particularly if temperature and precipitation change rapidly. We present an analysis of the role of climate and other factors in determining metapopulation structure based on presence and absence data. We compared existing and historical population distributions of desert bighorn sheep ( ) to determine whether regional climate patterns were correlated with local extinction. To examine all mountain ranges known to hold or to have held desert bighorn populations in California and score for variables describing climate, metapopulation dynamics, human impacts, and other environmental factors, we used a geographic information system (GIS) and paper maps. We used logistic regression and hierarchical partitioning to assess the relationship among these variables and the current status of each population (extinct or extant). Parameters related to climate—elevation, precipitation, and presence of dependable springs—were strongly correlated with population persistence in the twentieth century. Populations inhabiting lower, drier mountain ranges were more likely to go extinct. The presence of domestic sheep grazing allotments was negatively correlated with population persistence. We used conditional extinction probabilities generated by the logistic-regression model to rank native, naturally recolonized, and reintroduced populations by vulnerability to extinction under several climate-change scenarios. Thus risk of extinction in metapopulations can be evaluated for global-climate-change scenarios even when few demographic data are available.
   
   
   
6. Global Warming and Extinctions of Endemic Species from Biodiverstiy Hotspots. Malcolm, Jay R.; Liu, Canran; Neilson, Ronald P.; Hansen, Lara; Hannah, Lee.
   Conservation Biology: 2006
   Notes
   Global warming is a key threat to biodiversity, but few researchers have assessed the magnitude of this threat at the global scale. We used major vegetation types (biomes) as proxies for natural habitats and, based on projected future biome distributions under doubled-CO2 climates, calculated changes in habitat areas and associated extinctions of endemic plant and vertebrate species in biodiversity hotspots. Because of numerous uncertainties in this approach, we undertook a sensitivity analysis of multiple factors that included (1) two global vegetation models, (2) different numbers of biome classes in our biome classification schemes, (3) different assumptions about whether species distributions were biome specific or not, and (4) different migration capabilities. Extinctions were calculated using both species-area and endemic-area relationships. In addition, average required migration rates were calculated for each hotspot assuming a doubled-CO2 climate in 100 years. Projected percent extinctions ranged from <1 to 43% of the endemic biota (average 11.6%), with biome specificity having the greatest influence on the estimates, followed by the global vegetation model and then by migration and biome classification assumptions. Bootstrap comparisons indicated that effects on hotpots as a group were not significantly different from effects on random same-biome collections of grid cells with respect to biome change or migration rates; in some scenarios, however, hotspots exhibited relatively high biome change and low migration rates. Especially vulnerable hotspots were the Cape Floristic Region, Caribbean, Indo-Burma, Mediterranean Basin, Southwest Australia, and Tropical Andes, where plant extinctions per hotspot sometimes exceeded 2000 species. Under the assumption that projected habitat changes were attained in 100 years, estimated global-warming-induced rates of species extinctions in tropical hotspots in some cases exceeded those due to deforestation, supporting suggestions that global warming is one of the most serious threats to the planet's biodiversity.
   
   
   
7. Historic Fire Regime in Southern California Shrublands. Keeley, Jon E; Fotheringham, C J.
   Conservation Biology: 2001
   Notes
   Historical variability in fire regime is a conservative indicator of ecosystem sustainability, and thus uderstanding the natural role of fire in chaparral ecosystems is necessary for proper fire management. It has been suggested that the “natural” fire regime was one of frequent small fires that fragmented the landscape into a fine-grained mixture of age classes that precluded large, catastrophic fires. Some researchers claim that this regime was lost because of highly effective fire suppression and conclude that if fire managers could “restore" a regime of frequent fires with widespread prescription burning, they could eliminate the hazard of catastrophic fires. The primary evidence in support of this model is a study that compared contemporary burning patterns in southern California, U.S.A., a region subject to fire suppression, with patterns in northern Baja California, Mexico, where there is less effective fire suppression. We found that differences in fire regime between these two regions are inconclusive and could not be ascribed conclusively to differences in fire suppression. Historical records suggest that the natural fire regime in southern California shrublands was rather coarse-grained and not substantively different from the contemporary regime. There is no evidence that fire-management policies have created the contemporary fire regime dominated by massive Santa Ana wind-driven fires. Increased expenditures on fire suppression and increased loss of property and lives are the result of human demographic patterns that place increasing demand on fire-suppression forces.
   
   
   
8. Spatial tests of the pesticide drift, habitat destruction, UV-B, and climate-change hypotheses for California amphibian declines. Davidson, C.; Shaffer, H. B.; Jennings, M. R..
   Conservation Biology: 2002
   Notes
   Wind-borne pesticides have long been suggested as a cause of amphibian declines in areas without obvious habitat destruction. In California, the transport and deposition of pesticides from the agriculturally intensive Central Valley to the adjacent Sierra Nevada is well documented, and pesticides have been found in the bodies of Sierra frogs. Pesticides are therefore a plausible cause of declines, but to date no direct links have been found between pesticides and actual amphibian population declines. Using a geographic information system, we constructed maps of the spatial pattern of declines for eight declining California amphibian taxa, and compared the observed patterns of decline to those predicted by hypotheses of wind-borne pesticides, habitat destruction, ultraviolet radiation, and climate change. In four species, we found a strong positive association between declines and the amount of upwind agricultural land use, suggesting that wind-borne pesticides may be an important factor in declines. For two other species, declines were strongly associated with local urban and agricultural land use, consistent with the habitat-destruction hypothesis. The patterns of decline were not consistent with either the ultraviolet radiation or climate-change hypotheses for any of the species we examined.
   
   
   
9. When Agendas Collide: Human Welfare and Biological Conservation. Chan, Kai M. A.; Pringle, Robert M.; Ranganathan, J. A. I.; Boggs, Carol L.; Chan, Yvonne L.; Ehrlich, Paul R.; Haff, Peter K.; Heller, Nicole E.; Al-Khafaji, Karim; Macmynowski, Dena P..
   Conservation Biology: 2007
   DOI: doi:10.1111/j.1523-1739.2006.00570.x
   Notes
   Conservation should benefit ecosystems, nonhuman organisms, and current and future human beings. Nevertheless, tension among these goals engenders potential ethical conflicts: conservationists' true motivations may differ from the justifications they offer for their activities, and conservation projects have the potential to disempower and oppress people. We reviewed the promise and deficiencies of integrating social, economic, and biological concerns into conservation, focusing on research in ecosystem services and efforts in community-based conservation. Despite much progress, neither paradigm provides a silver bullet for conservation's most pressing problems, and both require additional thought and modification to become maximally effective. We conclude that the following strategies are needed to make conservation more effective in our human-dominated world. Conservation research needs to integrate with social scholarship in a more sophisticated manner. Conservation must be informed by a detailed understanding of the spatial, temporal, and social distributions of costs and benefits of conservation efforts. Strategies should reflect this understanding, particularly by equitably distributing conservation's costs. We must better acknowledge the social concerns that accompany biodiversity conservation; accordingly, sometimes we must argue for conservation for biodiversity's sake, not for its direct human benefits.