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Fragmentation and loss of natural habitat have important consequences for wild populations and can negatively affect long-term viability and resilience to environmental change. Salt marsh obligate species, such as those that occupy the San Francisco Bay Estuary in western North America, occupy already impaired habitats as result of human development and modifications and are highly susceptible to increased habitat loss and fragmentation due to global climate change. We examined the genetic variation of the California Ridgway’s rail ( Rallus obsoletus obsoletus), a state and federally endangered species that occurs within the fragmented salt marsh of the San Francisco Bay Estuary. We genotyped 107 rails across 11...
While the iconic Haleakalā silversword plant made a strong recovery from early 20th-century threats, it has now entered a period of substantial climate-related decline. New research published this week warns that global warming may have severe consequences for the silversword in its native habitat.
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Point transect distance sampling data were collected during the 2010 surveys of Alamagan, Commonwealth of the Northern Mariana Islands (CNMI). Data were collected at points along transects where trained observers recorded the detection type (heard, seen, or heard then seen) and horizontal distance (exact distance in m) from the station center point to individual birds detected during an 8-min count. To increase the numbers of detections, survey data from 40 detections from the CNMI Division of Fish and Wildlife (DFW; 2000) surveys of Alamagan, and 46 detections from Saipan surveys described in Camp et al. (2009) were added to this dataset. The count length of the DFW surveys was only 5 minutes; therefore, we included...
Abstract: Although climate change is predicted to place mountain-top and other narrowly endemic species at severe risk of extinction, the ecological processes involved in such extinctions are still poorly resolved. In addition, much of this biodiversity loss will likely go unobserved, and therefore largely unappreciated. The Haleakalā silversword is restricted to a single volcano summit in Hawai‘i, but is a highly charismatic giant rosette plant that is viewed by 1-2 million visitors annually. We link detailed local climate data to a lengthy demographic record, and combine both with a population-wide assessment of recent plant mortality and recruitment, to show that after decades of strong recovery following successful...
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The newly identified rapid ‘ohi‘a death (ROD; Metrosideros polymorpha) originated in the lower Puna district and its distribution has spread across Hawai‘i Island. As ROD expands it is expected that the loss of the dominant tree species will adversely affect bird populations. This project is a first attempt to describe the relationship between the impacts of ROD on the Hawaiian avifauna, especially the native Hawai‘i ‘amakihi (Hemignathus virens virens) an omnivore found in a wide range of native and nonnative habitat types. ‘Amakihi was generally rare below about 1,300 m elevation (Scott et al. 1986, Reynolds et al. 2003) but recent surveys found that the species is resident and breeding in native-dominated ‘ohi‘a...
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Point transect distance sampling data collected during the 2010 surveys of Alamagan, Commonwealth of the Northern Mariana Islands (CNMI). Data were collected at points along transects where trained observers recorded the detection type (heard, seen, or heard then seen) and horizontal distance (exact distance in m) from the station center point to individual birds detected during an 8-min count. To increase the numbers of detections, survey data from 40 detections from the CNMI Division of Fish and Wildlife (DFW; 2000) surveys of Alamagan, and 46 detections from Saipan surveys described in Camp et al. (2009). The count length of the DFW surveys was only 5 minutes; therefore, we included detections from the first...
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Point transect distance sampling data collected during the 2003 to 2016 surveys of lower Puna District, Hawai`i. Data were collected at points along rural highways, secondary roads and residential streets where trained observers recorded the detection type (heard, seen, or heard then seen) and horizontal distance (exact distance in m) from the station center point to individual birds detected during an 8-min count. The data set also includes covariates that may influence the detectability of birds.


    map background search result map search result map A Century of Landscape Disturbance and Urbanization of the San Francisco Bay Region affects the Present-day Genetic Diversity of the California Ridgway’s Rail (Rallus obsoletus obsoletus) Lower Puna, Hawai`i Island, bird and habitat surveys of 2003 and 2016 Point transect distance data from 2003 and 2016 surveys of lower Puna, Hawai`i Alamagan, Commonwealth of the Northern Mariana Islands, Nightingale Reed-warbler point transect survey data, 2010 Alamagan, Commonwealth of the Northern Mariana Islands, Nightingale Reed-warbler point transect survey data, 2010 Alamagan, Commonwealth of the Northern Mariana Islands, Nightingale Reed-warbler point transect survey data, 2010 Alamagan, Commonwealth of the Northern Mariana Islands, Nightingale Reed-warbler point transect survey data, 2010 Lower Puna, Hawai`i Island, bird and habitat surveys of 2003 and 2016 Point transect distance data from 2003 and 2016 surveys of lower Puna, Hawai`i