Publications by authors named "Dean Biggins"

The consequences of intraguild predation on vulnerable subordinate species are an important consideration in the recovery of endangered species. In prairie ecosystems, coyotes () are the primary predator of endangered black-footed ferrets (; hereafter, ferrets) and presumably compete for prairie dog ( spp.) prey.

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We evaluated the invasion of plague bacteria into a population of black-tailed prairie dogs (; BTPDs) in South Dakota. We aimed to ascertain if invaded slowly or rapidly, and to determine if vector (flea) control or vaccination of BTPDs assisted in increasing survival rates. We sampled BTPDs in 2007 (before documentation), 2008 (year of confirmed invasion), and 2009 (after invasion).

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Sylvatic plague, a primarily flea-borne zoonosis, is a significant threat to prairie dogs ( spp., PDs) and their specialized predators, endangered black-footed ferrets (, BFFs). Host-fed fipronil baits have proven effective in controlling fleas on PDs for the purposes of plague mitigation and BFF conservation.

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Parasite infrapopulation size - the population of parasites affecting a single host - is a central metric in parasitology. However, parasites are small and elusive such that imperfect detection is expected. Repeated sampling of parasites during primary sampling occasions (e.

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Plague, caused by the bacterium Yersinia pestis, is a zoonotic disease of mammalian hosts and flea vectors. Fipronil baits have been used to suppress adult fleas for plague mitigation. The degree and duration of flea control may increase if fipronil also kills other stages in the flea life cycle.

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Sylvatic plague is a widespread, primarily flea-vectored disease in western North America. Because plague is highly lethal to endangered black-footed ferrets (Mustela nigripes, BFFs) and the prairie dogs (Cynomys spp., PDs) on which BFFs depend for habitat and prey, minimizing the impacts of plague is a priority at BFF reintroduction sites.

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Plague and Trace Metals in Natural Systems.

Int J Environ Res Public Health

August 2022

All pathogenic organisms are exposed to abiotic influences such as the microclimates and chemical constituents of their environments. Even those pathogens that exist primarily within their hosts or vectors can be influenced directly or indirectly. Yersinia pestis, the flea-borne bacterium causing plague, is influenced by climate and its survival in soil suggests a potentially strong influence of soil chemistry.

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Background: Plague, a widely distributed zoonotic disease of mammalian hosts and flea vectors, poses a significant risk to ecosystems throughout much of Earth. Conservation biologists use insecticides for flea control and plague mitigation. Here, we evaluate the use of an insecticide grain bait, laced with 0.

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Prairie dogs in the western United States experience periodic epizootics of plague, caused by the flea-borne bacterial pathogen Yersinia pestis. An early study indicated that Oropsylla hirsuta (Baker), often the most abundant prairie dog flea vector of plague, seldom transmits Y. pestis by the classic blocked flea mechanism.

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Purpose Of Review: In 2020, the Appropriations Committee for the U.S. House of Representatives directed the CDC to develop a national One Health framework to combat zoonotic diseases, including sylvatic plague, which is caused by the flea-borne bacterium .

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The plague bacterium is lethal to endangered black-footed ferrets (, BFF) and the prairie dogs ( spp., PD) on which they depend for habitat and prey. We assessed the effectiveness of an oral sylvatic plague vaccine delivered in baits to black-tailed PD (, BTPD) from 2013 to 2017 on the Charles M.

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Scientists collect fleas (Siphonaptera) to survey for , the bacterial agent of plague. When studying fleas parasitizing prairie dogs ( spp.), two primary methods are used: (1) combing fleas from live-trapped prairie dogs and (2) swabbing fleas from burrows with cloth swabs attached to metal cables.

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Rodents characteristically benefit from increased precipitation, especially in typically dry habitats; "good years" of high precipitation improve their forage and water balance. However, (plague), a flea-borne pathogen of mammals that was introduced to western North America, has the greatest negative impact on at least some species of rodents during years of above-average precipitation. In the absence of plague mitigation, negative effects of plague in wet years might overwhelm the otherwise beneficial effects of increased moisture.

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In western North America, sylvatic plague (a flea-borne disease) poses a significant risk to endangered black-footed ferrets (Mustela nigripes) and their primary prey, prairie dogs (Cynomys spp.). Pulicides (flea-killing agents) can be used to suppress fleas and thereby manage plague.

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The plague bacterium, , is a generalist pathogen of flea (Siphonaptera) vectors and mammalian hosts. In colonies of prairie dogs (PDs, spp.), causes occasional epizootics, killing ≥90% of PDs within weeks to several months.

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Plague originated in Asia as a flea-borne zoonosis of mammalian hosts. Today, the disease is distributed nearly worldwide. In western United States of America, plague is maintained, transmitted, and amplified in diverse communities of rodents and fleas.

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Human health practitioners and wildlife biologists use insecticides to manage plague by suppressing fleas (Siphonaptera), but insecticides can also kill other ectoparasites. We investigated effects of deltamethrin and fipronil on ectoparasites from black-tailed prairie dogs (Cynomys ludovicianus, BTPDs). In late July, 2018, we treated three sites with 0.

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Plague is a bacterial zoonosis of mammalian hosts and flea vectors. The disease is capable of ravaging rodent populations and transforming ecosystems. Because plague mortality is likely to be predicted by flea parasitism, it is critical to understand vector dynamics.

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Plague is a flea-borne disease of mammalian hosts. On the grasslands of western North America, plague stifles populations of Cynomys spp. prairie dogs (PDs).

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Plague (caused by the bacterium ) is a deadly flea-borne disease that remains a threat to public health nearly worldwide and is particularly disruptive ecologically where it has been introduced. We review hypotheses regarding maintenance and transmission of , emphasizing recent data from North America supporting maintenance by persistent transmission that results in sustained non-epizootic (but variable) rates of mortality in hosts. This maintenance mechanism may facilitate periodic epizootic eruptions "in place" because the need for repeated reinvasion from disjunct sources is eliminated.

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Plague, a flea-borne disease, hampers efforts to restore populations of black-footed ferrets (), which occupy colonies of prairie dogs ( spp.) in North America. Plague is managed by infusing prairie dog burrows with DeltaDust 0.

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Sylvatic plague poses a substantial risk to black-tailed prairie dogs ( Cynomys ludovicianus) and their obligate predator, the black-footed ferret ( Mustela nigripes). The effects of plague on prairie dogs and ferrets are mitigated using a deltamethrin pulicide dust that reduces the spread of plague by killing fleas, the vector for the plague bacterium. In portions of Conata Basin, Buffalo Gap National Grassland, and Badlands National Park, South Dakota, US, 0.

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At Valles Caldera National Preserve in New Mexico, US, infusing Gunnison's prairie dog ( Cynomys gunnisoni) burrows with an insecticide dust containing 0.05% deltamethrin killed fleas which transmit bubonic plague. The reduction in the number of fleas per prairie dog was significant and dramatic immediately after infusions, with a suggestion that the reduction persisted for as long as 12 mo.

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Sylvatic plague vaccine (SPV) is a virally vectored bait-delivered vaccine expressing Yersinia pestis antigens that can protect prairie dogs (Cynomys spp.) from plague and has potential utility as a management tool. In a large-scale 3-year field trial, SPV-laden baits containing the biomarker rhodamine B (used to determine bait consumption) were distributed annually at a rate of approximately 100-125 baits/hectare along transects at 58 plots encompassing the geographic ranges of four species of prairie dogs.

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Sylvatic plague, caused by Yersinia pestis, frequently afflicts prairie dogs (Cynomys spp.), causing population declines and local extirpations. We tested the effectiveness of bait-delivered sylvatic plague vaccine (SPV) in prairie dog colonies on 29 paired placebo and treatment plots (1-59 ha in size; average 16.

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