Ward B. Stone

Bat White-Nose Syndrome: An Emerging Fungal Pathogen?

White-nose syndrome (WNS) is a condition associated with an unprecedented bat mortality event in the northeastern United States. Since the winter of 2006*2007, bat declines exceeding 75% have been observed at surveyed hibernacula. Affected bats often present with visually striking white fungal growth on their muzzles, ears, and/or wing membranes. Direct microscopy and culture analyses demonstrated that the skin of WNS-affected bats is colonized by a psychro-philic fungus that is phylogenetically related to Geomyces spp. but with a conidial morphology distinct from characterized members of this genus. This report characterizes the cutaneous fungal infection associated with WNS.

POISONING OF WILDLIFE WITH ANTICOAGULANT RODENTICIDES IN NEW YORK

From 1971 through 1997, we documented 51 cases (55 individual animals) of poisoning of non-target wildlife in New York (plus two cases in adjoining states) (USA) with anticoagulant rodenticides—all but two of these cases occurred in the last 8 yrs. Brodifacoum was implicated in 80% of the incidents. Diphacinone was identified in four cases, bromadiolone in three cases (once in combination with brodifacoum), and chlorophacinone and coumatetralyl were detected once each in the company of brodifacoum. Warfarin accounted for the three cases documented prior to 1989, and one case involving a bald eagle (Haliaeetus leucocephalus) in 1995. Secondary intoxication of raptors, principally great horned owls (Bubo virginianus) and red-tailed hawks (Buteo jamaicensis), comprised one-half of the cases. Gray squirrels (Sciurus carolinensis), raccoons (Procyon lotor) and white-tailed deer (Odocoileus virginianus) were the most frequently poisoned mammals. All of the deer originated from a rather unique situation on a barrier island off southern Long Island (New York). Restrictions on the use of brodifacoum appear warranted.

Morphological and molecular characterizations of psychrophilic fungus Geomyces destructans from New York bats with white nose syndrome (WNS).

Background Massive die-offs of little brown bats (Myotis lucifugus) have been occurring since 2006 in hibernation sites around Albany, New York, and this problem has spread to other States in the Northeastern United States. White cottony fungal growth is seen on the snouts of affected animals, a prominent sign of White Nose Syndrome (WNS). A previous report described the involvement of the fungus Geomyces destructans in WNS, but an identical fungus was recently isolated in France from a bat that was evidently healthy. The fungus has been recovered sparsely despite plentiful availability of afflicted animals. Methodology/Principal Findings We have investigated 100 bat and environmental samples from eight affected sites in 2008. Our findings provide strong evidence for an etiologic role of G. destructans in bat WNS. (i) Direct smears from bat snouts, Periodic Acid Schiff-stained tissue sections from infected tissues, and scanning electron micrographs of bat tissues all showed fungal structures similar to those of G. destructans. (ii) G. destructans DNA was directly amplified from infected bat tissues, (iii) Isolations of G. destructans in cultures from infected bat tissues showed 100% DNA match with the fungus present in positive tissue samples. (iv) RAPD patterns for all G. destructans cultures isolated from two sites were indistinguishable. (v) The fungal isolates showed psychrophilic growth. (vi) We identified in vitro proteolytic activities suggestive of known fungal pathogenic traits in G. destructans. Conclusions/Significance Further studies are needed to understand whether G. destructans WNS is a symptom or a trigger for bat mass mortality. The availability of well-characterized G. destructans strains should promote an understanding of bat–fungus relationships, and should aid in the screening of biological and chemical control agents.

Crow deaths caused by West Nile virus during winter.

In New York, an epizootic of American crow (Corvus brachyrhynchos) deaths from West Nile virus (WNV) infection occurred during winter 2004–2005, a cold season when mosquitoes are not active. Detection of WNV in feces collected at the roost suggests lateral transmission through contact or fecal contamination.

VecTest as Diagnostic and Surveillance Tool for West Nile Virus in Dead Birds

The VecTest WNV assay is adequate for diagnostic and surveillance purposes in American Crows, Blue Jays, and House Sparrows.

Biodiversity of Clostridium botulinum Type E Associated with a Large Outbreak of Botulism in Wildlife from Lake Erie and Lake Ontario

ABSTRACT The genetic relatedness of Clostridium botulinum type E isolates associated with an outbreak of wildlife botulism was studied using random amplification of polymorphic DNA (RAPD). Specimens were collected from November 2000 to December 2008 during a large outbreak of botulism affecting birds and fish living in and around Lake Erie and Lake Ontario. In our present study, a total of 355 wildlife samples were tested for the presence of botulinum toxin and/or organisms. Type E botulinum toxin was detected in 110 samples from birds, 12 samples from fish, and 2 samples from mammals. Sediment samples from Lake Erie were also examined for the presence of C. botulinum. Fifteen of 17 sediment samples were positive for the presence of C. botulinum type E. Eighty-one C. botulinum isolates were obtained from plants, animals, and sediments; of these isolates, 44 C. botulinum isolates produced type E toxin, as determined by mouse bioassay, while the remaining 37 isolates were not toxic for mice. All toxin-producing isolates were typed by RAPD; that analysis showed 12 different RAPD types and multiple subtypes. Our study thus demonstrates that multiple genetically distinct strains of C. botulinum were involved in the present outbreak of wildlife botulism. We found that C. botulinum type E is present in the sediments of Lake Erie and that a large range of bird and fish species is affected.

Necropsy Findings and Environmental Contaminants in Common Loons from New York

Diagnostic and analytical findings are presented for 105 common loons (Gavia immer) found dead or debilitated in New York (USA) from 1972–99. Aspergillosis (23% of cases) and ingestion of lead fishing weights (21%) were the most common pathologies encountered. Stranding on land, shooting, other trauma, gill nets, air sacculitis and peritonitis, and emaciation of uncertain etiology accounted for most of the remaining causes of disease or death. Analysis for total mercury in the liver of 83 loons yielded a geometric mean (gm) of 10.3 mg/kg (wet basis) and range of 0.07 to 371 mg/kg, with emaciated birds generally showing higher levels. Organochlorine contaminant levels in brain were generally low, principally consisting of PCBs (gm = 2.02 mg/kg) and DDE (0.47 mg/kg).

Levels of polychlorinated biphenyls (PCBs), DDE, and mirex in waterfowl collected in New York State, 1981–1982

Levels of polychlorobiphenyls (PCBs), DDE, and mirex were measured in the subcutaneous fat, breast muscle, liver, and brain of sixty-three waterfowl collected in New York State during 1979 and 1980. Mean PCB levels were 7.5 μg/g in fat and 1.3 μg/g in breast muscle on a wet weight basis. The FDA tolerance level is 3.0 μg/g in fat on a wet weight basis. Mean DDE and mirex levels were 0.34 μg/g and 0.10 μg/g in fat and 0.16 μg/g and 0.07 μg/g in breast muscle on a wet weight basis, respectively. Comparisons and correlations were made of contaminant levels in the various tissues by different concentration bases, and PCB concentrations were compared to the Aroclor® (PCB) type. Potential health hazards are discussed. Comparisons to earlier studies show declined levels. Mergansers are the most contaminated species.

Assays to Detect West Nile Virus in Dead Birds

Using oral swab samples to detect West Nile virus in dead birds, we compared the Rapid Analyte Measurement Platform (RAMP) assay with VecTest and real-time reverse-transcriptase–polymerase chain reaction. The sensitivities of RAMP and VecTest for testing corvid species were 91.0% and 82.1%, respectively.

Intentional Poisoning of Birds with Parathion

-Intentional poisoning of birds by farmers is not uncommon but is rarely documented and given proper attention. Two recent cases from New York are illustrative. In the first, at least 5,120 birds, mostly Red-winged Blackbirds (Ageu Tucker and Crabtree 1970, Schafer 1972). Accidental deaths of numerous wild birds have resulted from the agricultural use of parathion. White et al. (1982a, b) reported the deaths of over 1,600 waterfowl, mostly Canada Geese (Branta canadensis), from applications of parathion to agricultural fields in Texas. More insidious and less appreciated is the use of parathion to deliberately poison wild birds. Carson (1962) described the purposeful killing, by farmers, of an estimated 65,000 birds with parathion. Farmers continue to intentionally kill birds with parathion and this report describes the investigation of two recent cases in New York State.