637 research outputs found

    Producersā€™ perceptions of large carnivores and nonlethal methods to protect livestock from depredation: findings from a multistate federal initiative

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    We examined livestock producersā€™ perceptions of wolves, grizzly bears, black bears, and mountain lions, as well as their experiences with using nonlethal methods to protect livestock from depredation. All producers in the study received nonlethal predator management assistance in 2020 from USDA-APHIS-Wildlife Services (ā€œWSā€) pursuant to a federally funded initiative focused on the use of nonlethal methods to protect livestock. Such methods included assistance from range riders (i.e., individuals who monitor livestock and carnivores), fladry (i.e., flags hung from rope that serve as a repellent), and other audio/visual deterrents (e.g., Foxlights). The producers did not specifically seek nonlethal assistance from WS; rather, they sought assistance from WS with controlling depredation of livestock, and WS personnel determined that nonlethal methods were an appropriate fit for the circumstances. In some cases, lethal methods may have been used prior to, following, or in combination with, nonlethal methods on a producerā€™s operation. In addition, producers may have employed other nonlethal methods themselves, including fencing and livestock guardian animals. Our objectives were to understand the producersā€™ (1) experiences with, and attitudes toward, the four carnivores of interest; (2) perceptions of the effectiveness of all management methods (lethal and nonlethal) used their operations in 2020; and (3) levels of interest in using nonlethal methods, both before and after receiving assistance from WS in 2020. Data were collected using a self-administered, mail-back questionnaire. The questionnaire was sent to all producers in 10 US states1 who received nonlethal predator management assistance from WS in 2020 (n = 89). We received 40 responses (45% response rate), nearly three-quarters of which were from Montana (n = 13), Minnesota (n = 10), and Wisconsin (n = 6). A majority of respondents produced cattle (n = 28), followed by horses/mules (n = 11), sheep/goats (n = 6), honeybees (n = 3), and chickens (n = 2). Ten respondents produced multiple livestock types

    A social network analysis of actors involved in wild pig (\u3ci\u3eSus scrofa\u3c/i\u3e) management in Missouri

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    Wild pigs (Sus scrofa) cause significant damage to agriculture and native ecosystems and can transmit diseases to animals and people. Management responses designed to reduce population numbers are needed to mitigate these threats. Identifying networks of key actors, including the ways in which they interact, is valuable for purposes of better understanding opportunities or constraints that generate or impede effective management responses. The goal of our study was to understand the network of organizations, and the personnel working within them, that were active in wild pig management, research, or policy initiatives in Missouri during 2018ā€“2020 by 1) identifying individuals and organizations involved in the network, 2) investigating the attributes of relevant personnel, 3) determining the structural patterns of the network, and 4) examining how the network structure could be optimized to improve communication and collaboration efforts. Results from a social network analysis identified 150 personnel affiliated with 26 organizations actively working on wild pig issues in Missouri. The network was largely homogenous based on respondents\u27 attributes, had low density, and was relatively fragmented, small, decentralized with few ties per node, and separated with few brokers. We emphasize the importance of understanding the strengths and weaknesses of a network\u27s structure in facilitating effective collective action to manage wild pigs

    Machine Learning as a Tool for Wildlife Management and Research: The Case of Wild Pig-Related Content on Twitter

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    Wild pigs (Sus scrofa) are a non-native, invasive species that cause considerable damage and transmit a variety of diseases to livestock, people, and wildlife. We explored Twitter, the most popular social media micro-blogging platform, to demonstrate how social media data can be leveraged to investigate social identity and sentiment toward wild pigs. In doing so, we employed a sophisticated machine learning approach to investigate: (1) the overall sentiment associated with the dataset, (2) online identities via user profile descriptions, and (3) the extent to which sentiment varied by online identity. Results indicated that the largest groups of online identity represented in our dataset were females and people whose occupation was in journalism and media communication. While the majority of our data indicated a negative sentiment toward wild pigs and other related search terms, users who identified with agriculture-related occupations had more favorable sentiment. Overall, this article is an important starting point for further investigation of the use of social media data and social identity in the context of wild pigs and other invasive species

    Social identity and acceptability of wild pig (Sus scrofa) control actions: A case study of Texas hunters

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    Wild pigs (Sus scrofa) pose significant challenges to wildlife managers. This research explored Texas huntersā€™ acceptability of wild pig control actions, and whether acceptability varied according to huntersā€™ affiliation with four different categories of natural resource organizations as an indicator of social identity. Results of a survey (n = 37,317) revealed that most hunters were accepting of all control actions except toxicants and non-lethal deterrents. Mean acceptability scores for each action differed significantly across the four affiliation categories, but effect sizes were minimal. Hunters affiliated with agricultural organizations were the most accepting of control actions, while hunters with no organizational affiliations were least accepting. Findings suggested that while the type of organization with which a hunter affiliates provides some basis for predicting acceptability of control actions, the association is likely not significant enough to warrant differentiating wild pig outreach messaging on the basis of affiliation

    Texas Huntersā€™ Perceptions Regarding the Acceptability of Toxicants to Control Wild Pig Populations

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    Wild pigs (Sus scrofa) are an invasive species in the United States. They damage agriculture, degrade water quality and ecological communities, and host a number of viruses, parasites, and bacteria transmissible to humans and animals. In states such as Texas, USA, where wild pigs cause extensive damage to agriculture and property, officials have considered allowing for the use of toxicants to control wild pig populations. To provide decision-makers with information regarding stakeholdersā€™ perceptions of the use of toxicants to control wild pigs, we surveyed Texas hunters in 2019 to assess the level of acceptance of a hypothetical wild pig toxicant, the sociodemographic and other factors most closely associated with acceptability of such a toxicant, and the specific concerns that underlie huntersā€™ positions on the use of such a toxicant. We received 37,317 completed responses to an online, self-administered survey. Respondents were divided over the use of a toxicant, with 43% finding a toxicant acceptable, 18% neutral, and 39% finding a toxicant unacceptable. The factor most closely associated with acceptance of a wild pig toxicant was respondentsā€™ desired wild pig population size in Texas (Ļ‡2 = 3,657.7, P \u3c 0.001, V = 0.26), with 70% of respondents who preferred that wild pigs be completely removed from Texas finding the use of a toxicant to be acceptable, compared to 14% of respondents who preferred that wild pig populations increase or stay the same. The most commonly raised concerns in connection with toxicant usage were potential negative impacts to nontarget animals (33%) and negative impacts to human health (24%). Our research suggests that while achieving a consensus among Texas hunters on toxicant usage is unrealistic, building majority support may be possible if the identified concerns are sufficiently addressed in product development and outreach

    Effects of Defects on Photocatalytic Activity of Hydrogen-Treated Titanium Oxide Nanobelts

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    Previous studies have shown that hydrogen treatment leads to the formation of blue to black TiO_2, which exhibits photocatalytic activity different from that of white pristine TiO_2. However, the underlying mechanism remains poorly understood. Herein, density functional theory is combined with comprehensive analytical approaches such as X-ray absorption near edge structure spectroscopy and transient absorption spectroscopy to gain fundamental understanding of the correlation among the oxygen vacancy, electronic band structure, charge separation, charge carrier lifetime, reactive oxygen species (ROS) generation, and photocatalytic activity. The present work reveals that hydrogen treatment results in chemical reduction of TiO_2, inducing surface and subsurface oxygen vacancies, which create shallow and deep sub-band gap Ti(III) states below the conduction band. This leads to a blue color but limited enhancement of visible light photocatalytic activity up to 440 nm at the cost of reduced ultraviolet photocatalytic activity. The extended light absorption spectral range for reduced TiO_2 is ascribed to both the defect-to-conduction band transitions and the valence band-to-defect transitions. The photogenerated charge carriers from the defect states to the conduction band have lifetimes too short to drive photocatalysis. The Ti(III) deep and shallow trap states below the conduction band are also found to reduce the lifetime of photogenerated charge carriers under ultraviolet light irradiation. The ROS generated by the reduced TiO_2 are less than those generated by pristine TiO_2. Consequently, the reduced TiO_2 exhibits ultraviolet-responsive photocatalytic activity worse than that of pristine TiO_2. This report shows that increasing the light absorption spectral range of a semiconductor by doping or introduction of defects does not necessarily guarantee an increase in photocatalytic activity

    Effects of Defects on Photocatalytic Activity of Hydrogen-Treated Titanium Oxide Nanobelts

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    Previous studies have shown that hydrogen treatment leads to the formation of blue to black TiO_2, which exhibits photocatalytic activity different from that of white pristine TiO_2. However, the underlying mechanism remains poorly understood. Herein, density functional theory is combined with comprehensive analytical approaches such as X-ray absorption near edge structure spectroscopy and transient absorption spectroscopy to gain fundamental understanding of the correlation among the oxygen vacancy, electronic band structure, charge separation, charge carrier lifetime, reactive oxygen species (ROS) generation, and photocatalytic activity. The present work reveals that hydrogen treatment results in chemical reduction of TiO_2, inducing surface and subsurface oxygen vacancies, which create shallow and deep sub-band gap Ti(III) states below the conduction band. This leads to a blue color but limited enhancement of visible light photocatalytic activity up to 440 nm at the cost of reduced ultraviolet photocatalytic activity. The extended light absorption spectral range for reduced TiO_2 is ascribed to both the defect-to-conduction band transitions and the valence band-to-defect transitions. The photogenerated charge carriers from the defect states to the conduction band have lifetimes too short to drive photocatalysis. The Ti(III) deep and shallow trap states below the conduction band are also found to reduce the lifetime of photogenerated charge carriers under ultraviolet light irradiation. The ROS generated by the reduced TiO_2 are less than those generated by pristine TiO_2. Consequently, the reduced TiO_2 exhibits ultraviolet-responsive photocatalytic activity worse than that of pristine TiO_2. This report shows that increasing the light absorption spectral range of a semiconductor by doping or introduction of defects does not necessarily guarantee an increase in photocatalytic activity

    LKB1 is required for hepatic bile acid transport and canalicular membrane integrity in mice

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    LKB1 is a ā€˜masterā€™ protein kinase implicated in the regulation of metabolism, cell proliferation, cell polarity and tumorigenesis. However, the long-term role of LKB1 in hepatic function is unknown. In the present study, it is shown that hepatic LKB1 plays a key role in liver cellular architecture and metabolism. We report that liver-specific deletion of LKB1 in mice leads to defective canaliculi and bile duct formation, causing impaired bile acid clearance and subsequent accumulation of bile acids in serum and liver. Concomitant with this, it was found that the majority of BSEP (bile salt export pump) was retained in intracellular pools rather than localized to the canalicular membrane in hepatocytes from LLKB1KO (liver-specific Lkb1-knockout) mice. Together, these changes resulted in toxic accumulation of bile salts, reduced liver function and failure to thrive. Additionally, circulating LDL (low-density lipoprotein)-cholesterol and non-esterified cholesterol levels were increased in LLKB1KO mice with an associated alteration in red blood cell morphology and development of hyperbilirubinaemia. These results indicate that LKB1 plays a critical role in bile acid homoeostasis and that lack of LKB1 in the liver results in cholestasis. These findings indicate a novel key role for LKB1 in the development of hepatic morphology and membrane targeting of canalicular proteins

    Assessment in the service of learning: challenges and opportunities or Plus Ƨa Change, Plus cā€™est la mĆŖme Chose

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    This paper begins with a brief overview of literature indicating that, although there have been significant advances in the fieldā€™s capacity to conduct both formative and summative assessments over the past decades, those advances have not been matched by comparable impact. The bulk of the paper is devoted to a series of examples from the Mathematics Assessment Project that illustrate issues of methods, and the unrealized potential for advances
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