1,288 research outputs found

    The Economics of Threatened Species Conservation: A Review and Analysis

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    Stabilizing human population size and reducing human-caused impacts on the environment are keys to conserving threatened species (TS). Earth\u27s human population is ~ 7 billion and increasing by ~ 76 million per year. This equates to a human birth-death ratio of 2.35 annually. The 2007 Red List prepared by the International Union for Conservation of Nature and Natural Resources (IUCN) categorized 16,306 species of vertebrates, invertebrates, plants, and other organisms (e.g., lichens, algae) as TS. This is ~ 1 percent of the 1,589,161 species described by IUCN or ~ 0.0033 percent of the believed 5,000,000 total species. Of the IUCN’s described species, vertebrates comprised relatively the most TS listings within respective taxonomic categories (5,742 of 59,811), while invertebrates (2,108 of 1,203,175), plants (8,447 of 297,326), and other species (9 of 28,849) accounted for minor class percentages. Conservation economics comprises microeconomic and macroeconomic principles involving interactions among ecological, environmental, and natural resource economics. A sustainable-growth (steady-state) economy has been posited as instrumental to preserving biological diversity and slowing extinctions in the wild, but few nations endorse this approach. Expanding growth principles characterize most nations\u27 economic policies. To date, statutory fine, captive breeding cost, contingent valuation analysis, hedonic pricing, and travel cost methods are used to value TS in economic research and models. Improved valuation methods of TS are needed for benefit-cost analysis (BCA) of conservation plans. This Chapter provides a review and analysis of: (1) the IUCN status of species, (2) economic principles inherent to sustainable versus growth economies, and (3) methodological issues which hinder effective BCAs of TS conservation

    The Economics of Threatened Species Conservation: A Review and Analysis

    Get PDF
    Stabilizing human population size and reducing human-caused impacts on the environment are keys to conserving threatened species (TS). Earth\u27s human population is ~ 7 billion and increasing by ~ 76 million per year. This equates to a human birth-death ratio of 2.35 annually. The 2007 Red List prepared by the International Union for Conservation of Nature and Natural Resources (IUCN) categorized 16,306 species of vertebrates, invertebrates, plants, and other organisms (e.g., lichens, algae) as TS. This is ~ 1 percent of the 1,589,161 species described by IUCN or ~ 0.0033 percent of the believed 5,000,000 total species. Of the IUCN’s described species, vertebrates comprised relatively the most TS listings within respective taxonomic categories (5,742 of 59,811), while invertebrates (2,108 of 1,203,175), plants (8,447 of 297,326), and other species (9 of 28,849) accounted for minor class percentages. Conservation economics comprises microeconomic and macroeconomic principles involving interactions among ecological, environmental, and natural resource economics. A sustainable-growth (steady-state) economy has been posited as instrumental to preserving biological diversity and slowing extinctions in the wild, but few nations endorse this approach. Expanding growth principles characterize most nations\u27 economic policies. To date, statutory fine, captive breeding cost, contingent valuation analysis, hedonic pricing, and travel cost methods are used to value TS in economic research and models. Improved valuation methods of TS are needed for benefit-cost analysis (BCA) of conservation plans. This Chapter provides a review and analysis of: (1) the IUCN status of species, (2) economic principles inherent to sustainable versus growth economies, and (3) methodological issues which hinder effective BCAs of TS conservation

    CUE ENHANCEMENT OF LITHIUM-CHLORIDE-INDUCED MUTTON/SHEEP AVERSIONS IN COYOTES

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    In an enclosure-type study, I investigated the use of odor, auditory, and visual cues to enhance lithium-chloride (LiCl)- induced prey aversion in coyotes (Canis latrans). Eight adult, male, wild-caught coyotes that killed 2 adult sheep during successive daily, 1 -hr trials were assigned to LiCl- and sodium-chloride (NaCl)-bait groups. The 4 LiCl-bait coyotes were sequentially presented with leg-of-sheep and whole-sheep carcasses injected with a 33% LiCl water solution (4.5 ml/kg) 1 -hr daily until bait shy. The 4 NaCl coyotes were exposed to baits and carcasses injected with 25% NaCl/water solution (4.5 ml/kg) for matched trials. Additionally, 2 coyotes within each LiCl and NaCl group were presented with baits/carcasses sprayed with cologne and fitted with a red collar and attached bell, and 2 reference coyotes within each LiCl and NaCl group were offered similar baits/ carcasses without these stimuli. Following onset of bait aversion, coyotes were again paired for 1 hr daily with a live sheep that had either the stimuli or no stimuli affixed until 2 sheep were killed. Coyotes required 7 to 23 1-hr exposures to LiCl meats to cease ingestion (develop bait shyness). Coyotes presented both LiCl-baits/carcasses and subsequent live sheep affixed with stimuli showed greater suppression of predation, but this effect was of limited duration (\u3c9 pairings with sheep)

    SPREADSHEETS, RESPONSE SURFACES, AND INTERVENTION DECISIONS IN WILDLIFE DAMAGE MANAGEMENT

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    Abstract: An a priori approach to examining the economics of performing management activities to reduce agricultural and resource damage by wildlife is described. Computer spreadsheet procedures are used to derive response surfaces of potential net savings and benefit:cost indices for selected crop-or resource-protection activities. Tabular and graphical displays of these indices afford decision-making aids for wildlife-damage interventions. An example based on the use of an acute rodenticide, zinc phosphide (Zn 3 P 2 ), for vole (Microtus spp.) control in alfalfa (Medicago sativa) is described. Iterative calculations were derived for 1,260 possible combinations of 3 field-size, 6 crop-loss, 7 bait-effectiveness, and 10 application-fee variables. Average 1998 USDA alfalfa yield and price data (7.77 Mton‱ha -1 and US$100.33‱Mton ), served as the point of comparison. Effects were transitive, with greater net savings and benefit:cost ratios linked with larger field-size, crop-damage and bait-effectiveness variables, but decreased bait-application fees. Potential net savings were essentially negative when damage was <10%. Minimum and maximum benefit:cost ratios were 0.40 and 6.45; ratios ≄2.0 occurred typically when damage was ≄15%. The utility of the illustration and the approach are discussed

    Zinc Phosphide Residues in Gray-Tailed Voles (\u3ci\u3eMicrotus canicaudus\u3c/i\u3e) Fed Fixed Particles of a 2% Grain Bait

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    This study measured depelted-carcass residues of zinc phosphide (Zn3P2, CAS # 1314-84-7) in 8 (4 males and 4 females) gray-tailed voles (Microtus canicaudus). Six (3 males and 3 females) voles were confined individually in 1.89 dkl (5 gal) plastic pails that contained 5,2% Zn3P2 steamrolled- oat (SRO) groats; 2 voles (1 male and 1 female) served as analytical (unbaited) controls. Four test voles (3 males and 1female) died within 7.5 h after bait exposure; whereas, 2 test voles showed no signs of toxicosis and were euthanized 7.0 h after bait exposure. Whole carcasses were stored frozen and depelted carcasses were analyzed within 31 days for Zn3P2 residues using a acid-hydrolyzation, gas-chromatographic (GC) method. Analytical controls were euthanized, with carcasses stored and analyzed the same as test voles. A mean (± SD) 4.7 (±0.8) SRO groats were consumed by the test voles; this converted to a mean (±SD) intake of 2.15 (±0.38) mg Zn3P2 and dose of 73.25 mg/kg ( ± 22.95) Zn3P2. The mean (± SD) Zn3P2 residue in the 6 test vole carcasses was 0.42 mg (± 0.68); control carcasses contained \u3c0.009 mg Zn3P2- 3P2 in voles are variable, but typically \u3c 50% of ingested rodenticide and (2) risks of secondary poisoning posed by Zn3P2-baited voles to avian and mammalian predators/scavengers are low due to the relatively high toxic thresholds (\u3e 20 mg/kg) required to affect these species

    Impacts of Wildlife Diseases In Urban Environments

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    Approximately 60% of diseases causing pathogenic illness in humans originate in animals. Emergence and re-emergence of zoonotic and vector-borne diseases pose considerable public health, environmental, and economic impacts in the U.S. There are over 250 urban areas in the U.S. with populations \u3e 100,000. These densely populated centers, with concomitant development of natural areas, greenbelts, and walking trails, are viewed to exacerbate the potential for human-wildlife, pet-wildlife, and pet-human interactions leading to greater risks of zoonotic disease transmission. Wildlife rabies, West Nile virus (WNV), and bovine tuberculosis (bTB) offer illustrations of potential impacts from zoo noses in urban areas. Prevention of wildlife variants of the rabies virus are estimated to cost \u3e 250millionannually;probabletransmissioninurbanenvironmentscaninvolvedirecthumanexposuretorabidcoyotes(Canislatrans),raccoons(Procyonlotor),skunks(Mephitismephitis,Spilogaleputoris),andredfoxes(Vulpesvulpes)orindirectexposuretothevirusviapet−wildlifecontactswiththeseanimals.WestNilevirusisamosquito−borneillnessthathaskilled3˘e785peopleintheU.S.;hospitalizationcostsassociatedwiththeoutbreakofthisdiseaseinColorado2˘7sdenselypopulatedFrontRangeaveraged250 million annually; probable transmission in urban environments can involve direct human exposure to rabid coyotes (Canis latrans), raccoons (Procyon lotor), skunks (Mephitis mephitis, Spilogale putoris), and red foxes (Vulpes vulpes) or indirect exposure to the virus via pet-wildlife contacts with these animals. West Nile virus is a mosquito-borne illness that has killed \u3e785 people in the U.S.; hospitalization costs associated with the outbreak of this disease in Colorado\u27s densely populated Front Range averaged 33,980/admitted patient. The re-emergence of bovine tuberculosis (bTB) in cattle (Bovidae spp.) of Michigan\u27s northern Lower Peninsula has resulted in a loss of the State\u27s TB-accredited free status costing the state an estimated $22-74 million in five years. Monitoring, preventing, and treating zoonotic diseases pose new challenges for public health, veterinary, and wildlife professionals, with densely populated urban environments likely to exacerbate transmission and impacts

    Computational fluid dynamic analysis of bioprinted self-supporting perfused tissue models

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    Natural tissues are incorporated with vasculature, which is further integrated with a cardiovascular system responsible for driving perfusion of nutrient‐rich oxygenated blood through the vasculature to support cell metabolism within most cell‐dense tissues. Since scaffold‐free biofabricated tissues being developed into clinical implants, research models, and pharmaceutical testing platforms should similarly exhibit perfused tissue‐like structures, we generated a generalizable biofabrication method resulting in self‐supporting perfused (SSuPer) tissue constructs incorporated with perfusible microchannels and integrated with the modular FABRICA perfusion bioreactor. As proof of concept, we perfused an MLO‐A5 osteoblast‐based SSuPer tissue in the FABRICA. Although our resulting SSuPer tissue replicated vascularization and perfusion observed in situ, supported its own weight, and stained positively for mineral using Von Kossa staining, our in vitro results indicated that computational fluid dynamics (CFD) should be used to drive future construct design and flow application before further tissue biofabrication and perfusion. We built a CFD model of the SSuPer tissue integrated in the FABRICA and analyzed flow characteristics (net force, pressure distribution, shear stress, and oxygen distribution) through five SSuPer tissue microchannel patterns in two flow directions and at increasing flow rates. Important flow parameters include flow direction, fully developed flow, and tissue microchannel diameters matched and aligned with bioreactor flow channels. We observed that the SSuPer tissue platform is capable of providing direct perfusion to tissue constructs and proper culture conditions (oxygenation, with controllable shear and flow rates), indicating that our approach can be used to biofabricate tissue representing primary tissues and that we can model the system in silico

    Novel diterpenes with potent conidiation inducing activity

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    The isolation and structure determination of conidiogenol and conidiogenone, tetracyclic diterpenes with a novel carbon skeleton, from extracts of the fermentation broth of Penicillium cyclopium is reported. Conidiogenol and conidiogenone are potent and selective inducers of conidiogenesis in P. cyclopium in liquid culture, and relay information about the environmental conditions to the producing organism. (C) 2002 Elsevier Science Ltd. All rights reserved
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