6 research outputs found

    Assessing Biofuel Crop Invasiveness: A Case Study

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    BACKGROUND: There is widespread interest in biofuel crops as a solution to the world's energy needs, particularly in light of concerns over greenhouse-gas emissions. Despite reservations about their adverse environmental impacts, no attempt has been made to quantify actual, relative or potential invasiveness of terrestrial biofuel crops at an appropriate regional or international scale, and their planting continues to be largely unregulated. METHODOLOGY/PRINCIPAL FINDINGS: Using a widely accepted weed risk assessment system, we analyzed a comprehensive list of regionally suitable biofuel crops to show that seventy percent have a high risk of becoming invasive versus one-quarter of non-biofuel plant species and are two to four times more likely to establish wild populations locally or be invasive in Hawaii or in other locations with a similar climate. CONCLUSIONS/SIGNIFICANCE: Because of climatic and ecological similarities, predictions of biofuel crop invasiveness in Hawaii are applicable to other vulnerable island and subtropical ecosystems worldwide. We demonstrate the utility of an accessible and scientifically proven risk assessment protocol that allows users to predict if introduced species will become invasive in their region of interest. Other evidence supports the contention that propagule pressure created by extensive plantings will exacerbate invasions, a scenario expected with large-scale biofuel crop cultivation. Proactive measures, such as risk assessments, should be employed to predict invasion risks, which could then be mitigated via implementation of appropriate planting policies and adoption of the "polluter-pays" principle

    The vaccination of 35,000 dogs in 20 working days using combined static point and door-to-door methods in Blantyre, Malawi

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    An estimated 60,000 people die of rabies annually. The vast majority of cases of human rabies develop following a bite from an infected dog. Rabies can be controlled in both human and canine populations through widespread vaccination of dogs. Rabies is particularly problematic in Malawi, costing the country an estimated 13 million USD and 484 human deaths annually, with an increasing paediatric incidence in Blantyre City. Consequently, the aim of this study was to vaccinate a minimum of 75% of all the dogs within Blantyre city during a one month period. Blantyre's 25 administrative wards were divided into 204 working zones. For initial planning, a mean human:dog ratio from the literature enabled estimation of dog population size and dog surveys were then performed in 29 working zones in order to assess dog distribution by land type. Vaccination was conducted at static point stations at weekends, at a total of 44 sites, with each operating for an average of 1.3 days. On Monday to Wednesday, door-to-door vaccination sessions were undertaken in the areas surrounding the preceding static point stations. 23,442 dogs were vaccinated at static point stations and 11,774 dogs were vaccinated during door-to-door vaccinations. At the end of the 20 day vaccination programme, an assessment of vaccination coverage through door-to-door surveys found that of 10,919 dogs observed, 8,661 were vaccinated resulting in a vaccination coverage of 79.3% (95%CI 78.6-80.1%). The estimated human:dog ratio for Blantyre city was 18.1:1. Mobile technology facilitated the collection of data as well as efficient direction and coordination of vaccination teams in near real time. This study demonstrates the feasibility of vaccinating large numbers of dogs at a high vaccination coverage, over a short time period in a large African city

    Status of management and control efforts for the invasive alien tree Miconia calvescens DC. (Melastomataceae) in Hana, East Maui

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    Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.This report is a conglomeration of the research and monitoring that has been conducted in the area of the Hana Miconia calvescens population since this weed was addressed as a biological threat to native Hawaiian ecosystems in 1991. Despite the amount of time that was spent in the area, and the abundance of useful information that was gathered during the course of the past nine years, many important questions concerning the biology and ecology of M. calvescens, particularly as they apply to the Hawaiian Islands, have yet to be answered

    Notes on Status and Ecology of the Endangered Hawaiian Annual Awiwi, Centaurium sebaeoides (Gentianaceae)

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    The annual, endemic, coastal herb Centaurium sebaeoides is the only native Hawaiian species in the gentian family. The U.S. Fish and Wildlife Service listed it as Endangered under the Endangered Species Act on 29 October 1991. Before surveys reported here, the total population of this species statewide was estimated at 80-110 individuals in eight populations. During counts made in April and May 1997, following ample winter rains, 12 populations of C. sebaeoides with a total of 6300-6600 plants were noted on five islands (Kaua'i, O'ahu, Lana'i, Moloka'i, and Maui). Five populations were mapped with a global positioning system and counted; in the remaining seven populations, the numbers of individuals were estimated. More recent surveys in 1998-1999 estimated a total of only 60-80 individuals at all sites. Such dramatic population fluctuations are believed to be related to the sporadic occurrence of winter rains. Threats that further contribute to the rarity of the species include (1) displacement and overtopping by salt-tolerant nonnative woody species, especially Casuarina spp., (2) trampling and erosion of habitat by ungulates, and (3) damage caused by off-road vehicles
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