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1.
Conserv Biol ; 36(2): e13860, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34766386

RESUMO

When in 2010 the world's governments pledged to increase protected area coverage to 17% of the world's land surface, several Central African countries had already set aside 25% of their northern savannas for conservation. To evaluate the effectiveness of this commitment, we analyzed the results of 68 multispecies surveys conducted in the seven main savanna national parks in Central Africa (1960-2017). We also assembled information on potential drivers of large herbivore population trends (rainfall and number of rangers) and on tourist numbers and revenues. In six out of the seven parks, wild large herbivore populations declined dramatically over time, livestock numbers increased severalfold, and tourism, the pillar under a once thriving local wildlife industry, collapsed. Zakouma National Park (Chad) stood out because its large herbivore populations increased, an increase that was positively correlated with rainfall and number of rangers (a proxy for management inputs). With increasing insecurity and declining revenues, governments find themselves confronted with too few resources to protect vast areas. To deal with this conversation overstretch, we propose to extend the repeatedly promoted solutions--scaled up funding, enhanced management--with a strategic retreat, focusing scarce resources on smaller areas to save wildlife in the Central African savannas.


Sobredimensionamiento de la Conservación y la Declinación a Largo Plazo de la Fauna y el Turismo en las Sabanas de África Central Resumen Cuando los gobiernos del mundo se comprometieron en 2010 a incrementar la cobertura de áreas protegidas al 17% de la superficie terrestre del planeta, varios países del centro de África ya habían dispuesto el 25% de sus sabanas ubicadas al norte de la región para la conservación. Para evaluar la efectividad de este compromiso, analizamos los resultados de 68 censos multiespecies realizados en los siete parques nacionales principales de la sabana en África Central (1960-2017). También ensamblamos información sobre los causantes principales de las tendencias poblacionales de los grandes herbívoros (lluvias, número de guardaparques) y sobre las cifras e ingresos del turismo. En seis de los siete parques, las poblaciones de los grandes herbívoros silvestres declinaron dramáticamente con el tiempo, el número de cabezas de ganado incrementó varias veces y el turismo, el pilar de una industria faunística próspera en su momento, colapsó. El Parque Nacional Zakouma en Chad resaltó debido a que las poblaciones de herbívoros grandes incrementaron en esta localidad, un incremento que estuvo relacionado positivamente con las lluvias y el número de guardabosques (un sustituto para las aportaciones de manejo). Con el incremento en la inseguridad y la declinación de los ingresos, los gobiernos se encuentran de frente con muy pocos recursos para proteger áreas extensas. Para afrontar este sobredimensionamiento de la conservación, proponemos ampliar las soluciones que se promueven repetidamente - incrementos al financiamiento, manejo mejorado - con un repliegue estratégico, el cual enfoque los recursos escasos en las áreas más pequeñas para rescatar a la fauna de las sabanas del centro de África.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Animais , Conservação dos Recursos Naturais/métodos , Ecossistema , Pradaria , Turismo
3.
Proc Natl Acad Sci U S A ; 115(51): 12859-12867, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30487220

RESUMO

Current theoretical models of the commons assert that common-pool resources can only be managed sustainably with clearly defined boundaries around both communities and the resources that they use. In these theoretical models, open access inevitably leads to a tragedy of the commons. However, in many open-access systems, use of common-pool resources seems to be sustainable over the long term (i.e., current resource use does not threaten use of common-pool resources for future generations). Here, we outline the conditions that support sustainable resource use in open property regimes. We use the conceptual framework of complex adaptive systems to explain how processes within and couplings between human and natural systems can lead to the emergence of efficient, equitable, and sustainable resource use. We illustrate these dynamics in eight case studies of different social-ecological systems, including mobile pastoralism, marine and freshwater fisheries, swidden agriculture, and desert foraging. Our theoretical framework identifies eight conditions that are critical for the emergence of sustainable use of common-pool resources in open property regimes. In addition, we explain how changes in boundary conditions may push open property regimes to either common property regimes or a tragedy of the commons. Our theoretical model of emergent sustainability helps us to understand the diversity and dynamics of property regimes across a wide range of social-ecological systems and explains the enigma of open access without a tragedy. We recommend that policy interventions in such self-organizing systems should focus on managing the conditions that are critical for the emergence and persistence of sustainability.


Assuntos
Modelos Teóricos , Alocação de Recursos , Agricultura , Conservação dos Recursos Naturais , Ecossistema , Pesqueiros , Humanos , Propriedade
5.
Ambio ; 32(1): 58-64, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12691493

RESUMO

Integrated Conservation and Development Projects (ICDPs) aim to stimulate conservation without the previous negative experiences for local people, but pay little attention to their long-term impact such as immigration. The rehabilitation of the Logone floodplain in North Cameroon, the core activity of the Waza-Logone ICDP, has led to a 34% increase of sedentary fishermen and a multiple number of temporary fishermen. Whereas livestock pressure tripled, kob antelopes, a key floodplain species, have not increased, reducing their competitiveness. The virtual disappearance of wildlife in nearby Kalamaloué National Park (NP), due to advanced human encroachment forms, is therefore a bleak perspective for Waza NP. Examples from the Central African Republic (CAR), Galapagos, Nigeria and Zimbabwe also showed that in open-access systems, improvement in living standards (development) may stimulate immigration, jeopardizing the stability necessary in protected areas (conservation). Most ICDPs lack demographic monitoring, masking its possible immigration risk. To counter the immigration risk in Waza, a policy was formulated based on local stakeholder categorization and subsequent privileges, resulting in the voluntarily displacement of a village out of Waza NP. It is further recommended that ICDPs should be involved in regional land-use planning and discourage development activities that stimulate immigration.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Emigração e Imigração , Pesqueiros , Dinâmica Populacional , Animais , Animais Domésticos , Camarões , Meio Ambiente , Humanos
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