Effects of protected area downsizing on habitat fragmentation in Yosemite National Park (USA), 1864 - 2014

Protected area downgrading, downsizing, and degazettement (PADDD) has been documented worldwide, but its impacts on biodiversity are poorly understood. To fill this knowledge gap, we reviewed historical documents to identify legal changes that altered the boundaries of Yosemite National Park. We identified two downsizes and five additions between 1905 and 1937 that reduced the size of Yosemite National Park by 30%. To examine the effects of these downsizing events on habitat fragmentation by roads, we compared protected, never-protected, and downsized lands at three spatial scales using four habitat fragmentation metrics: road density, fragment (land surrounded by roads) area-to-perimeter ratio, fragment area, and fragment density. In general, lands that were removed from protection, e.g., downsized, were more highly fragmented than protected lands and indistinguishable from never-protected lands. Lands where downsizes were reversed were less fragmented than lands where downsizes were not reversed. These results suggest that protected area downsizing may exacerbate habitat fragmentation, a key contributor to biodiversity loss globally. Furthermore, the case study in Yosemite National Park demonstrates that iconic protected areas in developed countries are not immune to downsizing. These findings underscore the need to account for PADDD and governance histories in ecological research, monitoring, and evaluation. As we move toward more evidence-based conservation policy, a rigorous understanding of PADDD is essential to ensure that protected areas fulfill their promise as a strategy for conserving global biodiversity

The uncertain future of protected lands and waters

Las áreas protegidas están destinadas a salvaguardar la biodiversidad a perpetuidad, sin embargo, la evidencia sugiere que los cambios legales generalizados socavan la durabilidad y eficacia de las áreas protegidas. Documentamos estos cambios legales (eventos de degradación, reducción y eliminación de clasificación de áreas protegidas (PADDD)) en los Estados Unidos y los países amazónicos y compilamos los datos disponibles a nivel mundial. Los gobiernos de los Estados Unidos y los países amazónicos promulgaron 269 y 440 eventos PADDD, respectivamente. Entre 1892 y 2018, 73 países promulgaron 3749 eventos PADDD, eliminando 519,857 kilómetros cuadrados de las regulaciones de protección y templado en 1,659,972 kilómetros cuadrados adicionales; El 78% de los eventos se promulgaron desde 2000. La mayoría de los eventos PADDD (62%) están asociados con la extracción y el desarrollo de recursos a escala industrial, lo que sugiere que PADDD puede comprometer los objetivos de conservación de la biodiversidad. Se necesitan respuestas de políticas estratégicas para abordar la PADDD y mantener áreas protegidas efectivas.Protected areas are intended to safeguard biodiversity in perpetuity, yet evidence suggests that widespread legal changes undermine protected area durability and efficacy. We documented these legal changes—protected area downgrading, downsizing, and degazettement (PADDD) events—in the United States and Amazonian countries and compiled available data globally. Governments of the United States and Amazonian countries enacted 269 and 440 PADDD events, respectively. Between 1892 and 2018, 73 countries enacted 3749 PADDD events, removing 519,857 square kilometers from protection and tempering regulations in an additional 1,659,972 square kilometers; 78% of events were enacted since 2000. Most PADDD events (62%) are associated with industrial-scale resource extraction and development, suggesting that PADDD may compromise biodiversity conservation objectives. Strategic policy responses are needed to address PADDD and sustain effective protected areas.Q1Reflexión Económica, Administrativa y Contable (REAC

El futuro incierto de las tierras y aguas protegidas

Las áreas protegidas están destinadas a salvaguardar la biodiversidad a perpetuidad, sin embargo, la evidencia sugiere que los cambios legales generalizados socavan la durabilidad y eficacia de las áreas protegidas. Documentamos estos cambios legales (eventos de degradación, reducción y eliminación de clasificación de áreas protegidas (PADDD)) en los Estados Unidos y los países amazónicos y compilamos los datos disponibles a nivel mundial. Los gobiernos de los Estados Unidos y los países amazónicos promulgaron 269 y 440 eventos PADDD, respectivamente. Entre 1892 y 2018, 73 países promulgaron 3749 eventos PADDD, eliminando 519,857 kilómetros cuadrados de las regulaciones de protección y templado en 1,659,972 kilómetros cuadrados adicionales; El 78% de los eventos se promulgaron desde 2000. La mayoría de los eventos PADDD (62%) están asociados con la extracción y el desarrollo de recursos a escala industrial, lo que sugiere que PADDD puede comprometer los objetivos de conservación de la biodiversidad. Se necesitan respuestas de políticas estratégicas para abordar la PADDD y mantener áreas protegidas efectivas.Protected areas are intended to safeguard biodiversity in perpetuity, yet evidence suggests that widespread legal changes undermine protected area durability and efficacy. We documented these legal changes-protected area downgrading, downsizing, and degazettement (PADDD) events-in the United States and Amazonian countries and compiled available data globally. Governments of the United States and Amazonian countries enacted 269 and 440 PADDD events, respectively. Between 1892 and 2018, 73 countries enacted 3749 PADDD events, removing 519,857 square kilometers from protection and tempering regulations in an additional 1,659,972 square kilometers; 78% of events were enacted since 2000. Most PADDD events (62%) are associated with industrial-scale resource extraction and development, suggesting that PADDD may compromise biodiversity conservation objectives. Strategic policy responses are needed to address PADDD and sustain effective protected areas.Q1Reflexión Económica, Administrativa y Contable (REAC