Habitat Loss and Extinction in the Hotspots of Biodiversity

@article{citeulike:1398444, abstract = {Nearly half the world's vascular plant species and one-third of terrestrial vertebrates are endemic to 25 "hotspots" of biodiversity, each of which has at least 1500 endemic plant species. None of these hotspots have more than one-third of their pristine habitat remaining. Historically, they covered 12\% of the land's surface, but today their intact habitat covers only 1.4\% of the land. As a result of this habitat loss, we expect many of the hotspot endemics to have either become extinct or-because much of the habitat loss is recent-to be threatened with extinction. We used World Conservation Union [ IUCN ] Red Lists to test this expectation. Overall, between one-half and two-thirds of all threatened plants and 57\% of all threatened terrestrial vertebrates are hotspot endemics. For birds and mammals, in general, predictions of extinction in the hotspots based on habitat loss match numbers of species independently judged extinct or threatened. In two classes of hotspots the match is not as close. On oceanic islands, habitat loss underestimates extinction because introduced species have driven extinctions beyond those caused by habitat loss on these islands. In large hotspots, conversely, habitat loss overestimates extinction, suggesting scale dependence (this effect is also apparent for plants). For reptiles, amphibians, and plants, many fewer hotspot endemics are considered threatened or extinct than we would expect based on habitat loss. This mismatch is small in temperate hotspots, however, suggesting that many threatened endemic species in the poorly known tropical hotspots have yet to be included on the IUCN Red Lists. We then asked in which hotspots the consequences of further habitat loss (either absolute or given current rates of deforestation) would be most serious. Our results suggest that the Eastern Arc and Coastal Forests of Tanzania-Kenya, Philippines, and Polynesia-Micronesia can least afford to lose more habitat and that, if current deforestation rates continue, the Caribbean, Tropical Andes, Philippines, Mesoamerica, Sundaland, Indo-Burma, Madagascar, and Choco-Darien-Western Ecuador will lose the most species in the near future. Without urgent conservation intervention, we face mass extinctions in the hotspots. Perdida de Habitat y Extinciones en Areas Criticas para la Biodiversidad Resumen: Casi la mitad del total de plantas vasculares del mundo y un tercio de los vertebrados terrestres son endemicos en 25 "areas criticas" para la biodiversidad, cada una de las cuales tiene por lo menos 1500 especies de plantas endemicas. En ninguno de estos sitios permanece mas de un tercio de su habitat pristino. Historicamente, cubrian 12\% de la superficie terrestre, pero en la actualidad su habitat intacto cubre solo 1.4\% del terreno. Como resultado de esta perdida de habitat esperamos que muchas de las especies endemicas a estos sitios esten extintas o - porque la perdida de habitat es reciente - se encuentren amenazadas de extincion. Utilizamos Listas Rojas de UICN para comprobar esta prediccion. En general, entre la mitad y dos tercios de las plantas amenazadas y el 57\% de los vertebrados terrestres amenazados son endemicos de areas criticas para la biodiversidad. Para aves y mamiferos en general, las predicciones de extincion en las areas criticas para la biodiversidad, basadas en la perdida de habitat, coinciden con el numero de especies consideradas extintas o amenazadas independientemente. En dos clases de areas criticas para la biodiversidad la coincidencia no es muy grande. En islas oceanicas, la perdida de habitat subestima la extincion porque las especies introducidas han causado mas extinciones que las producidas por la reduccion del habitat. Por lo contrario, la perdida de habitat sobrestima la extincion en areas criticas para la biodiversidad extensas, lo que sugiere una dependencia de escala (este efecto tambien es aparente para plantas). Para reptiles, anfibios y plantas mucho menos especies endemicas son consideradas amenazadas o extintas por perdida de habitat. Sin embargo, esta discordancia es pequena en areas criticas para la biodiversidad en zonas templadas templadas, lo que sugiere que muchas especies endemicas amenazadas en las poco conocidas areas criticas para la biodiversidad en zonas tropicales aun estan por incluirse en las Listas Rojas. Posteriormente nos preguntamos en que areas criticas para la biodiversidad serian mas serias las consecuencias de una mayor perdida de habitat (absoluta o con las tasas actuales de deforestacion). Nuestros resultados sugieren que el Arco Oriental y los Bosques Costeros de Tanzania/Kenia, Filipinas, Polinesia/Micronesia no pueden soportar mayores perdidas y que, si continuan las tasas de deforestacion actuales, el Caribe, Andes Tropicales, Filipinas, Mesoamerica, Sundaland, Indo-Burma, Madagascar y Choco/Darien/Ecuador Occidental perderan mas especies en el futuro. Sin acciones urgentes de conservacion, habra extinciones masivas en las areas criticas para la biodiversidad.}, author = {Brooks, Thomas M. and Mittermeier, Russell A. and Mittermeier, Cristina G. and da Fonseca, Gustavo A. and Rylands, Anthony B. and Konstant, William R. and Flick, Penny and Pilgrim, John and Oldfield, Sara and Magin, Georgina and Hilton-Taylor, Craig }, citeulike-article-id = {1398444}, comment = {Brooks, T.M., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A., Rylands, A.B., Konstant, W.R., Flick, P., Pilgrim, J., Oldfield, S., Magin, G., Hilton-Taylor, C. 2002. Habitat Loss and Extinction in the Hotspots of Biodiversity. Conservation Biology 16(4):909-923.}, doi = {http://dx.doi.org/10.1046/j.1523-1739.2002.00530.x}, journal = {Conservation Biology}, keywords = {criteria, deforestation, endemism, hotspots, mdb, trees, vulnerability}, number = {4}, pages = {909--923}, posted-at = {2007-06-19 12:04:34}, priority = {0}, title = {Habitat Loss and Extinction in the Hotspots of Biodiversity}, url = {http://dx.doi.org/10.1046/j.1523-1739.2002.00530.x}, volume = {16}, year = {2002} }

TY - JOUR ID - citeulike:1398444 L3 - citeulike-article-id:1398444 N2 - Nearly half the world's vascular plant species and one-third of terrestrial vertebrates are endemic to 25 "hotspots" of biodiversity, each of which has at least 1500 endemic plant species. None of these hotspots have more than one-third of their pristine habitat remaining. Historically, they covered 12% of the land's surface, but today their intact habitat covers only 1.4% of the land. As a result of this habitat loss, we expect many of the hotspot endemics to have either become extinct or-because much of the habitat loss is recent-to be threatened with extinction. We used World Conservation Union [ IUCN ] Red Lists to test this expectation. Overall, between one-half and two-thirds of all threatened plants and 57% of all threatened terrestrial vertebrates are hotspot endemics. For birds and mammals, in general, predictions of extinction in the hotspots based on habitat loss match numbers of species independently judged extinct or threatened. In two classes of hotspots the match is not as close. On oceanic islands, habitat loss underestimates extinction because introduced species have driven extinctions beyond those caused by habitat loss on these islands. In large hotspots, conversely, habitat loss overestimates extinction, suggesting scale dependence (this effect is also apparent for plants). For reptiles, amphibians, and plants, many fewer hotspot endemics are considered threatened or extinct than we would expect based on habitat loss. This mismatch is small in temperate hotspots, however, suggesting that many threatened endemic species in the poorly known tropical hotspots have yet to be included on the IUCN Red Lists. We then asked in which hotspots the consequences of further habitat loss (either absolute or given current rates of deforestation) would be most serious. Our results suggest that the Eastern Arc and Coastal Forests of Tanzania-Kenya, Philippines, and Polynesia-Micronesia can least afford to lose more habitat and that, if current deforestation rates continue, the Caribbean, Tropical Andes, Philippines, Mesoamerica, Sundaland, Indo-Burma, Madagascar, and Choco-Darien-Western Ecuador will lose the most species in the near future. Without urgent conservation intervention, we face mass extinctions in the hotspots. Perdida de Habitat y Extinciones en Areas Criticas para la Biodiversidad Resumen: Casi la mitad del total de plantas vasculares del mundo y un tercio de los vertebrados terrestres son endemicos en 25 "areas criticas" para la biodiversidad, cada una de las cuales tiene por lo menos 1500 especies de plantas endemicas. En ninguno de estos sitios permanece mas de un tercio de su habitat pristino. Historicamente, cubrian 12% de la superficie terrestre, pero en la actualidad su habitat intacto cubre solo 1.4% del terreno. Como resultado de esta perdida de habitat esperamos que muchas de las especies endemicas a estos sitios esten extintas o - porque la perdida de habitat es reciente - se encuentren amenazadas de extincion. Utilizamos Listas Rojas de UICN para comprobar esta prediccion. En general, entre la mitad y dos tercios de las plantas amenazadas y el 57% de los vertebrados terrestres amenazados son endemicos de areas criticas para la biodiversidad. Para aves y mamiferos en general, las predicciones de extincion en las areas criticas para la biodiversidad, basadas en la perdida de habitat, coinciden con el numero de especies consideradas extintas o amenazadas independientemente. En dos clases de areas criticas para la biodiversidad la coincidencia no es muy grande. En islas oceanicas, la perdida de habitat subestima la extincion porque las especies introducidas han causado mas extinciones que las producidas por la reduccion del habitat. Por lo contrario, la perdida de habitat sobrestima la extincion en areas criticas para la biodiversidad extensas, lo que sugiere una dependencia de escala (este efecto tambien es aparente para plantas). Para reptiles, anfibios y plantas mucho menos especies endemicas son consideradas amenazadas o extintas por perdida de habitat. Sin embargo, esta discordancia es pequena en areas criticas para la biodiversidad en zonas templadas templadas, lo que sugiere que muchas especies endemicas amenazadas en las poco conocidas areas criticas para la biodiversidad en zonas tropicales aun estan por incluirse en las Listas Rojas. Posteriormente nos preguntamos en que areas criticas para la biodiversidad serian mas serias las consecuencias de una mayor perdida de habitat (absoluta o con las tasas actuales de deforestacion). Nuestros resultados sugieren que el Arco Oriental y los Bosques Costeros de Tanzania/Kenia, Filipinas, Polinesia/Micronesia no pueden soportar mayores perdidas y que, si continuan las tasas de deforestacion actuales, el Caribe, Andes Tropicales, Filipinas, Mesoamerica, Sundaland, Indo-Burma, Madagascar y Choco/Darien/Ecuador Occidental perderan mas especies en el futuro. Sin acciones urgentes de conservacion, habra extinciones masivas en las areas criticas para la biodiversidad. IS - 4 JF - Conservation Biology EP - 923 TI - Habitat Loss and Extinction in the Hotspots of Biodiversity VL - 16 SP - 909 KW - criteria KW - deforestation KW - endemism KW - hotspots KW - mdb KW - trees KW - vulnerability N1 - Brooks, T.M., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A., Rylands, A.B., Konstant, W.R., Flick, P., Pilgrim, J., Oldfield, S., Magin, G., Hilton-Taylor, C. 2002. Habitat Loss and Extinction in the Hotspots of Biodiversity. Conservation Biology 16(4):909-923. AU - Brooks, Thomas AU - Mittermeier, Russell AU - Mittermeier, Cristina AU - da Fonseca, Gustavo AU - Rylands, Anthony AU - Konstant, William AU - Flick, Penny AU - Pilgrim, John AU - Oldfield, Sara AU - Magin, Georgina AU - Hilton-Taylor, Craig PY - 2002/// UR - http://dx.doi.org/10.1046/j.1523-1739.2002.00530.x ER -