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James D. Jacobi

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This layer depicts the status, or degree of disturbance, to plant communities on the main Hawaiian Islands. To more precisely identify areas where native species may presently be found, a map was generated that considers the following three categories of habitat quality: High, areas dominated by native vegetation; Medium, areas dominated by nonnative vegetation; and Low, highly modified landscapes. The primary source for mapping these three categories is the HIGAP land-cover classification (Gon, 2006). The High category includes all HIGAP land-cover classes that are considered to be either native dominated or mixed native and nonnative in order to represent those areas that have substantial native-species composition....
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Hawaiʹi’s most widespread native tree, ʹōhiʹa lehua (Metrosideros polymorpha), has been dying across large areas of Hawaiʹi Island mainly due to two fungal pathogens (Ceratocystis lukuohia and Ceratocystis huliohia) that cause a disease collectively known as Rapid ʹŌhiʹa Death (ROD). Here we examine patterns of positive detections of C. lukuohia as it has been linked to the larger mortality events across Hawaiʹi Island. Our analysis compares the environmental range of C. lukuohia and its spread over time through the known climatic range and distribution of ʹōhiʹa. This data set is a georeferenced raster file, containing the projected potential presence of C.lukuohia across the main Hawaiian Islands using climatic...
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This dataset provides information on the current status and various other habitat and descriptive attributes of the native coastal vegetation for seven of the main Hawaiian Islands (i.e., does not include Ni`ihau).
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We measured mature tree and sapling density, tree associations, crown size, age structure, recovery from ungulate browsing, and grass cover at four study sites in two types of subalpine woodland on Mauna Kea volcano, island of Hawaii. Beginning in 1981, introduced ungulates were reduced in number to allow regeneration of Sophora chrysophylla (mamane) in habitat supporting the endangered Hawaiian finch, Loxioides bailleui (palila). We found Sophora regeneration at all four study sites, but regeneration was higher in mixed species woodland with codominant Myoporum sandwicense (naio) than in areas where Sophora dominated. Regeneration of Myoporum was uniformly very low in comparison. Invasive grass cover, which suppresses...
Categories: Publication; Types: Citation; Tags: Biotropica
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In the early 1970s, a multidisciplinary team of forest biologists began a study of Hawaiian ecosystems under the International Biological Program (IBP). Research focus was on the intact native ecosystems in and around Hawai'i Volcanoes National Park, in particular the ʻŌhiʻa Lehua rainforest. Patches of dead ʻŌhiʻa stands had been reported from the windward slopes of Mauna Loa and Mauna Kea. Subsequent air photo analyses by a team of US and Hawai'i State foresters discovered rapidly spreading ʻŌhiʻa dieback, also called ʻŌhiʻa forest decline. A killer disease was suspected to destroy the Hawaiian rain forest in the next 15-25 years. Ecological research continued with a focus on the dynamics of the Hawaiian rainforest....
Categories: Publication; Types: Citation
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