Abstract： The Bogota Savannah was great Lake Humboldt 20,000 years ago. In the early 20th century, there were 50,000 ha of wetlands in Bogotá, but now this area has reduced to around 800 ha, due principally to h...Abstract： The Bogota Savannah was great Lake Humboldt 20,000 years ago. In the early 20th century, there were 50,000 ha of wetlands in Bogotá, but now this area has reduced to around 800 ha, due principally to human activities like industry, city-planning expansion, and agriculture. Actually, there are 13 wetlands and two lakes in Bogotá. SW （Salitre wetland） is an aquatic area that contains migratory and resident bird＇s species. Around this wetland, there are some urbanization and recreational areas that affect this natural habitat. Due to city-planning expansion, the city government wanted to build a great area to perform massive public events on the Salitre area. From June 2009 to June 2010, the researchers have made bird monitoring and recorded the SW as a very important habitat for birds; they demonstrated that this site offered them food and protection. Migratory species like Dendroica striata, Porzana carolina, Porphyrio martinica, Actitis macularia, Piranga rubra, Contopus cooperi and Contopus virens, inhabit this area. Most of the birds in SW use the area primarily for feeding and roosting, and the authors have recorded presence of eggs and chicks. In this way, the authors have demonstrated that this area is very important for migratory and resident birds. Currently, SW is in process to be officially designated as a wetland after many efforts. However, conservation and educational efforts should be taken into consideration for the protection and conservation of this wetland.展开更多
The proliferation of urban development with concentration in population and human-environment interaction has intensified around urban environments. This has resulted in the degradation of urban environments, overuse ...The proliferation of urban development with concentration in population and human-environment interaction has intensified around urban environments. This has resulted in the degradation of urban environments, overuse of natural resources and widespread pollution of ecosystems, The patterns of design initiatives continue to follow unsustainable path with impacts on stream ecosystems. Accordingly, the paper adopts geospatial information systems and sustainability principles for the identification and sequential mapping of stressors impeding natural systems in Southern Mississippi. The results not only reveal that the study area experienced some significant changes in its watershed environments, but the stream habitat ecosystem remains under stress. The recommendations for mitigating the problems range from policy considerations to the adoption of ecosystem approach.展开更多
The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amo...The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amongst habitat types remains unclear in India. We attempted to estimate bird assemblages in terms of diversity, species composition, status and abun- dance in urban and forest habitats of Nainital district of Uttarakhand （350-2450 m asl; 29N）, Western Himalayas. We sampled different elevational gradients and to understand the effect of urbanization and season on avian community composition. Field studies were conducted during January 2005 to January 2007. Results indicated that the forest had more complex bird community structure in terms of higher species richness （14.35 vs 8.69）, higher species diversity （Shannon＇s index 4.00 vs 3.54）, higher evenness （0.838 vs 0.811） and more rare species （17 vs 5） as compared to urban habitat. However, the abundance of 11 species was higher in urban habitats. Bird Species Richness （BSR） varied considerably among study areas （91 to 113 species）, was high- est （113 species） at mid elevation （1450-1700 m asl） and decreased （22 species） at high elevation （1900-2450 m asl）. It seems that high BSR at mid altitudes is not caused by the presence of a group of mid altitude specialists but rather that there is an over- lap in the distribution of low land and high elevation specialists at this altitude. BSR and Bird Species Diversity fluctuated across seasons but not habitat type [Current Zoology 57 （3）： 318-329,2011].展开更多
Urbanization and exotic species are major threats to the conservation of forest-dependent wildlife species. Some emblematic species, indicators of habitat quality for the conservation of other spe- cies, might success...Urbanization and exotic species are major threats to the conservation of forest-dependent wildlife species. Some emblematic species, indicators of habitat quality for the conservation of other spe- cies, might successfully be reintroduced within cities when habitat restoration and pest manage- ment programs are combined. We studied the landscape resource selection of juvenile kaka Nestor meridionalis tracked with Global Positioning System （GPS） units and released into the predator- free reserve of Zealandia in Wellington city, New Zealand. Kaka moved beyond the predator exclu- sion fence into urban suburbs. The home range size and areas of high use estimated using local convex hull （a-LoCoH） ranged from 20 to 240 ha and 2 to 21 ha, respectively. Using resource selec- tion functions and model selection we found that native forest patches and urban areas close to the reserve were selected by kaka to establish their home ranges. At a lower scale of selection （i.e., se- lection of habitats within home ranges）, kaka selected the same habitat, but not necessarily those close to the reserve. Native forest patches throughout the city can facilitate the dispersal of individ- uals, while the reserve provides protection and opportunities for supplementary feeding. Urban areas might have been selected due to the placement of feeders in private backyards. Survival of forest-dwelling species in cities requires careful urban planning and management to provide the necessary habitat patches, refugia, and food sources.展开更多
文摘Abstract： The Bogota Savannah was great Lake Humboldt 20,000 years ago. In the early 20th century, there were 50,000 ha of wetlands in Bogotá, but now this area has reduced to around 800 ha, due principally to human activities like industry, city-planning expansion, and agriculture. Actually, there are 13 wetlands and two lakes in Bogotá. SW （Salitre wetland） is an aquatic area that contains migratory and resident bird＇s species. Around this wetland, there are some urbanization and recreational areas that affect this natural habitat. Due to city-planning expansion, the city government wanted to build a great area to perform massive public events on the Salitre area. From June 2009 to June 2010, the researchers have made bird monitoring and recorded the SW as a very important habitat for birds; they demonstrated that this site offered them food and protection. Migratory species like Dendroica striata, Porzana carolina, Porphyrio martinica, Actitis macularia, Piranga rubra, Contopus cooperi and Contopus virens, inhabit this area. Most of the birds in SW use the area primarily for feeding and roosting, and the authors have recorded presence of eggs and chicks. In this way, the authors have demonstrated that this area is very important for migratory and resident birds. Currently, SW is in process to be officially designated as a wetland after many efforts. However, conservation and educational efforts should be taken into consideration for the protection and conservation of this wetland.
文摘The proliferation of urban development with concentration in population and human-environment interaction has intensified around urban environments. This has resulted in the degradation of urban environments, overuse of natural resources and widespread pollution of ecosystems, The patterns of design initiatives continue to follow unsustainable path with impacts on stream ecosystems. Accordingly, the paper adopts geospatial information systems and sustainability principles for the identification and sequential mapping of stressors impeding natural systems in Southern Mississippi. The results not only reveal that the study area experienced some significant changes in its watershed environments, but the stream habitat ecosystem remains under stress. The recommendations for mitigating the problems range from policy considerations to the adoption of ecosystem approach.
文摘The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amongst habitat types remains unclear in India. We attempted to estimate bird assemblages in terms of diversity, species composition, status and abun- dance in urban and forest habitats of Nainital district of Uttarakhand （350-2450 m asl; 29N）, Western Himalayas. We sampled different elevational gradients and to understand the effect of urbanization and season on avian community composition. Field studies were conducted during January 2005 to January 2007. Results indicated that the forest had more complex bird community structure in terms of higher species richness （14.35 vs 8.69）, higher species diversity （Shannon＇s index 4.00 vs 3.54）, higher evenness （0.838 vs 0.811） and more rare species （17 vs 5） as compared to urban habitat. However, the abundance of 11 species was higher in urban habitats. Bird Species Richness （BSR） varied considerably among study areas （91 to 113 species）, was high- est （113 species） at mid elevation （1450-1700 m asl） and decreased （22 species） at high elevation （1900-2450 m asl）. It seems that high BSR at mid altitudes is not caused by the presence of a group of mid altitude specialists but rather that there is an over- lap in the distribution of low land and high elevation specialists at this altitude. BSR and Bird Species Diversity fluctuated across seasons but not habitat type [Current Zoology 57 （3）： 318-329,2011].
文摘Urbanization and exotic species are major threats to the conservation of forest-dependent wildlife species. Some emblematic species, indicators of habitat quality for the conservation of other spe- cies, might successfully be reintroduced within cities when habitat restoration and pest manage- ment programs are combined. We studied the landscape resource selection of juvenile kaka Nestor meridionalis tracked with Global Positioning System （GPS） units and released into the predator- free reserve of Zealandia in Wellington city, New Zealand. Kaka moved beyond the predator exclu- sion fence into urban suburbs. The home range size and areas of high use estimated using local convex hull （a-LoCoH） ranged from 20 to 240 ha and 2 to 21 ha, respectively. Using resource selec- tion functions and model selection we found that native forest patches and urban areas close to the reserve were selected by kaka to establish their home ranges. At a lower scale of selection （i.e., se- lection of habitats within home ranges）, kaka selected the same habitat, but not necessarily those close to the reserve. Native forest patches throughout the city can facilitate the dispersal of individ- uals, while the reserve provides protection and opportunities for supplementary feeding. Urban areas might have been selected due to the placement of feeders in private backyards. Survival of forest-dwelling species in cities requires careful urban planning and management to provide the necessary habitat patches, refugia, and food sources.
