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Steven C Hess

Hawai‘i’s endangered waterbirds have experienced epizootics caused by ingestion of prey that accumulated a botulinum neurotoxin produced by the anaerobic bacterium Clostridium botulinum (avian botulism; Type C). Waterbird carcasses, necrophagous flies, and their larvae initiate and spread avian botulism, a food-borne paralytic disease lethal to waterbirds. Each new carcass has potential to develop toxin-accumulating necrophagous vectors amplifying outbreaks and killing hundreds of endangered birds. Early carcass removal is an effective mitigation strategy for preventing avian intoxication, toxin concentration in necrophagous and secondary food webs, and reducing the magnitude of epizootics. However, rapid detection...
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This dataset was developed to model habitat suitability for two ungulate species on the island of Lanai. This includes raster data derived from WorldView-2 data to create a normalized difference vegetation index (NDVI). This index, in addition to other datasets, was used to develop habitat suitability models for Axis deer and mouflon sheep. Datasets and indices derived for use in modeling efforts, as well as suitability models, are included within this data release.
Broadly, recovery of threatened and endangered species requires specific management actions by natural resource managers at a fine scale. We used a systematic conservation planning framework to outline conservation goals across multiple land-uses, including native habitat protection and identifying endangered species-specific recovery areas while minimizing intrusion on existing hunting areas on the island of Lanai. We used spatial prioritization tools to generate multiple scenarios where both conservation and hunting areas (deemed zones for analysis purposes) were delineated to meet land-use goals. These delineated areas will help land managers to minimize conflicts between uses for populations of non-native game...
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Our objectives were to examine the population history of axis deer on Maui, estimate observed population growth, and then use species-specific demographic parameters in a VORTEX population viability analysis to examine removal scenarios that would most effectively reduce the population. Only nine deer were introduced in 1959, but recent estimates of >10,000 deer suggest population growth rates (r) ranging between 0.147 and 0.160 although at least 11,200 have been removed by hunters and resource managers. In the VORTEX simulations, we evaluated an initial population size of 6,000 females and 4,000 males, reflecting the probable 3F:2M sex ratio on Maui because of male biased hunting. Scenarios were modeled over a...
Hawai‘i’s endangered waterbirds have experienced epizootics caused by ingestion of prey that accumulated a botulinum neurotoxin produced by the anaerobic bacterium Clostridium botulinum (avian botulism; Type C). Waterbird carcasses, necrophagous flies, and their larvae initiate and spread avian botulism, a food-borne paralytic disease lethal to waterbirds. Each new carcass has potential to develop toxin-accumulating necrophagous vectors amplifying outbreaks and killing hundreds of endangered birds. Early carcass removal is an effective mitigation strategy for preventing avian intoxication, toxin concentration in necrophagous and secondary food webs, and reducing the magnitude of epizootics. However, rapid detection...
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