1,052 research outputs found

    CALL BROADCASTING AND AUTOMATED RECORDERS AS TOOLS FOR ANURAN SURVEYS IN A SUBARCTIC TUNDRA LANDSCAPE

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    Relatively little is known about population ecology of anurans in arctic and subarctic tundra regions, in part because it is difficult to survey anurans in these landscapes. Anuran survey protocols developed for temperate regions have limited applicability in arctic and subarctic tundra landscapes, which may lack roads and vehicle access, and experience variable and inclement weather during short anuran breeding seasons. To evaluate approaches to address some of the limitations of surveying anurans in tundra landscapes, we assessed the effectiveness of using breeding call broadcasts to increase detection of Boreal Chorus Frogs (Pseudacris maculata) and Wood Frogs (Lithobates sylvaticus) near Cape Churchill, Manitoba, Canada. We also evaluated how counts of anurans derived from automated audio recorders compared with those obtained simultaneously by observers. We detected on average 0.4 additional Wood Frogs per survey when we broadcasted calls (x = 0.82, SD = 1.38), an increase of > 40% compared to surveys without broadcasts (x = 1.24, SD = 1.51; Wilcoxon test; Z = 2.73, P = 0.006). In contrast, broadcasting Boreal Chorus Frog calls did not increase the number of chorus frog detections (Wilcoxon test; Z < 0.001, P > 0.90). Detections of Wood Frogs in a 100-m radius were lower via automated recorders (x = 0.60, SD = 0.87 SD) than by observers during simultaneous surveys (x = 0.96, SD = 1.27 Z = 2.07, P = 0.038), but those of Boreal Chorus Frogs were not different (x = 1.72, SD = 1.31;x = 1.44, SD = 1.5; Z = 1.55, P > 0.121). Our results suggest that broadcasting calls can increase detection of Wood Frogs, and that automated recorders are useful in detecting both Wood Frogs and Boreal Chorus Fogs in arctic and subarctic tundra landscapes

    Differential Uptake of Gold Nanoparticles by 2 Species of Tadpole, the Wood Frog (Lithobates Sylvaticus) and the Bullfrog (Lithobates Catesbeianus)

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    Engineered nanoparticles are aquatic contaminants of emerging concern that exert ecotoxicological effects on a wide variety of organisms. We exposed cetyltrimethylammonium bromide–capped spherical gold nanoparticles to wood frog and bullfrog tadpoles with conspecifics and in combination with the other species continuously for 21 d, then measured uptake and localization of gold. Wood frog tadpoles alone and in combination with bullfrog tadpoles took up significantly more gold than bullfrogs. Bullfrog tadpoles in combination with wood frogs took up significantly more gold than controls. The rank order of weight-normalized gold uptake was wood frogs in combination \u3e wood frogs alone \u3e bullfrogs in combination \u3e bullfrogs alone \u3e controls. In all gold-exposed groups of tadpoles, gold was concentrated in the anterior region compared with the posterior region of the body. The concentration of gold nanoparticles in the anterior region of wood frogs both alone and in combination with bullfrogs was significantly higher than the corresponding posterior regions. We also measured depuration time of gold in wood frogs. After 21 d in a solution of gold nanoparticles, tadpoles lost \u3e83% of internalized gold when placed in gold-free water for 5 d. After 10 d in gold-free water, tadpoles lost 94% of their gold. After 15 d, gold concentrations were below the level of detection. Our finding of differential uptake between closely related species living in similar habitats with overlapping geographical distributions argues against generalizing toxicological effects of nanoparticles for a large group of organisms based on measurements in only one species

    UPDATED GEOGRAPHIC DISTRIBUTIONS OF MICHIGAN HERPETOFAUNA:: A SYNTHESIS OF OLD AND NEW SOURCES

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    Recently a comprehensive overview of reptiles and amphibians in Michigan was published. Unfortunately, the distributions of the species represented were compiled before widespread accessibility to technological tools providing greater access to museum and historical records as well as citizen science efforts. To update the known ranges of Michigan herpetofauna, published literature, museum collections, and photographic vouchers submitted to an online database were examined and 339 new county and island records were added, updating the maps for 48 of Michigan’s 55 known species of reptiles and amphibians. I also present the first published list of Michigan amphibians that includes two new plethodontid salamanders, the Northern Dusky Salamander (Desmognathus fuscus) and Southern Two-lined Salamander (Eurycea cirrigera). This paper serves as an example of the wealth of information available to scientists that may have previously been unobtainable, and can be used for the distribution of herpetofauna elsewhere

    NEW AND UPDATED RECORDS FOR AMPHIBIANS AND REPTILES IN MINNESOTA, USA

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    Following the publication of the revised edition of “Amphibians and Reptiles in Minnesota” by Moriarty and Hall (2014), we accessioned several new or updated records at the Bell Museum of Natural History (JFBM). Records include digital photographs (accession number preceded by “P”) and audio recordings (accession number preceded by “AUD”). In addition, a subset of these observations were accessioned in www.HerpMapper.org. HerpMapper accession numbers are preceded by “HM” and can be viewed online. Benjamin Lowe verified species determinations. Latitude and longitude coordinates are based on datum WGS 84

    SECOND INTERNATIONAL SYMPOSIUM ON RANAVIRUSES:: A NORTH AMERICAN HERPETOLOGICAL PERSPECTIVE

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    Ranaviruses are large double stranded DNA viruses of poikilothermic vertebrates including amphibians, reptiles and fish. In North America, ranaviral disease and ranavirus-related die-off events have been documented in all three classes. Ranaviruses are found worldwide, appear to be emerging in some regions, and are increasingly recognized as a threat to many species

    Pathogenesis of frog virus 3 (Ranavirus sp, Iridoviridae) in the wood frog, Rana sylvatica (Lithobates sylvaticus)

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    Amphibian populations suffer massive mortalities from infection with Frog Virus 3 (FV3, Ranavirus, Iridoviridae), a pathogen also responsible for mortalities of fish and reptiles. Wood frogs, Rana sylvatica, have been proposed as a research model to study diseases of native amphibians in North America. Our objectives were: 1) describe the longbterm housing, feeding and veterinary care of wildbcaught wood frogs, 2) develop a Ranavirusb wood frog model of infection with FV3, 3) review the literature on amphibian clinical pathology, 4) determine hematological reference intervals (RIs) for adult wood frogs and the hematological alterations associated with infection with FV3, and 5) establish the chronology of lesions due to a lethal infection with FV3. Wildbcaught adults and tadpoles were collected from Prince Edward Island and maintained in captivity for up to a year. Survival was good for wildbcaught individuals: 75 % for wildbcaught adults and 77 % for tadpoles raised to adulthood. A dose trial on adults raised from wildbcaught tadpoles established a lethal dose 50 (LD50) of 102.93 (2.42b3.44) pfu of FV3 for frogs averaging 35 mm in length. Onset of clinical signs occurred 6b14 days postbinfection (dpi) (median 11 dpi) and timebtobdeath 10b14 dpi (median 12 dpi). Each tenbfold increase in virus dose increased the odds of dying by 23bfold and accelerated onset of clinical signs and death by approximately 15%. Ranavirus DNA was demonstrated in skin and liver of all frogs that died or were euthanized because of severe clinical signs. Shedding of virus occurred in feces (7b10 dpi; 3b4.5 d before death) and skin sheds (10 dpi; 0b1.5 d before death) of some frogs that died from infection. Most common lesions were dermal erosion and hemorrhages, hematopoietic necrosis in bone marrow, kidney, spleen and liver, necrosis in renal glomeruli and in tongue, gastrointestinal tract, and urinary bladder mucosa. Intracytoplasmic inclusion bodies (probably viral) were present in the bone marrow and the epithelia of the oral cavity, gastrointestinal tract, renal tubules and urinary bladder. A timebcourse trial on wildbcaught adults using a lethal dose of FV3 (104.43 pfu/frog) followed by euthanasia at 0.25, 0.5, 1, 2, 4, 9 and 14 dpi established pathogenesis and hematological alterations due to infection. Infection with FV3 caused neutrophilia, increase in undifferentiated blastblike cells and relative reduction of basophils. Lymphocytes decreased at 4 and 9 dpi but increased 14 dpi. From 9 dpi onwards, nuclear deterioration and mild toxic change were present in neutrophils; cytoplasmic inclusion bodies were present in lymphocytes, monocytes, neutrophils and eosinophils. FV3 first targets hematopoietic tissue in the bone marrow and endothelial cells in the skin causing very mild microscopic lesions (1b2 dpi). Approximately 9 dpi, FV3 caused severe lesions in medullary and extamedullary hematopoietic tissue, lymphoid tissue and epithelial cells of skin and mucosae throughout the body. Direct contact (skin) and fecalboral contamination are likely effective routes of transmission

    Additional Vertebrate Records and Natural History Notes from Arkansas

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    Although vertebrates are a commonly studied group of animals, the distribution and natural history of many species within Arkansas is still not well understood or documented. However, recently several new distribution and natural history notes have been published in a continuing series regarding Arkansas’s vertebrates (e.g. Tumlison and Robison 2010; Connior et al. 2011, Connior et al. 2012). Thus, we continue to augment current literature with new records of distribution and provide notes on the natural history of selected vertebrates from Arkansas. All voucher specimens (physical or photographic) are deposited in the vertebrate collections at either Arkansas State University (ASUMZ), Henderson State University (HSU), or South Arkansas University (SAU)

    The Faculty Notebook, September 2017

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    The Faculty Notebook is published periodically by the Office of the Provost at Gettysburg College to bring to the attention of the campus community accomplishments and activities of academic interest. Faculty are encouraged to submit materials for consideration for publication to the Associate Provost for Faculty Development. Copies of this publication are available at the Office of the Provost

    Relative abundance of amphibians in forest canopy gaps of natural origin vs. timber harvest origin

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    Small-scale canopy gaps created by logging may retain adequate habitat structure to maintain amphibian abundance. We used pitfalls with drift fences to measure relative abundance of amphibians in 44 harvested gaps, 19 natural treefall gaps, and 36 closed-canopy forest plots. Metamorphs had relatively lower capture rates in large harvest gaps for Ambystoma maculatum, Lithobates catesbeianus, L. clamitans, and L. sylvaticus but we did not detect statistically significant (p < 0.1) differences among gap types for Lithobates palustris metamorphs. L. clamitans juveniles and L. sylvaticus juveniles and adults had relatively lower capture rates in large harvest gaps. For juvenile-adult A. maculatum, we caught relatively fewer individuals in all gap types than in closed-canopy areas. Some groups with overall lower capture rates (immature Plethodon cinereus, juvenile L. palustris) had mixed differences among gap types, and Notophthalmus viridescens (efts) and adult P. cinereus showed no differences among gap types. One species, L. clamitans, was captured more often at gap edges than gap centers. These results suggest that harvest gaps, especially small gaps, provided habitat similar to natural gaps for some, but not all, amphibian species or life-stages

    PRESENCE AND PREVALENCE OF BD (BATRACHOCHYTRIUM DENDROBATIDIS) IN CENTRAL PENNSYLVANIAN WOODLAND VERNAL POOLS

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    Batrachochytrium dendrobatidis (Bd), a virulent chytrid fungus responsible for dramatic amphibian declines, has been detected in the northwestern and southeastern regions of Pennsylvania. However, little environmental Bd testing has been performed in central Pennsylvania, particularly in the unique and speciose habitats of woodland vernal pools. Our study included sampling in four vernal pools over a period of three months during amphibian breeding periods. Skin swabs were taken from three caudate and two anuran species, during the course of late winter and spring migrations (n = 143). Low Bd zoospore equivalent loads were detected in only a few individuals, in three of the five species but in all four vernal pools sampled. No significant trends were seen between zoospore loads and ambient temperature or migration timing across the species sampled
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