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Drinking water is a critical resource for hibernating bats and its importance may be further increased when disease affects water balance. White-nose syndrome (WNS), a fungal disease that causes dehydration and electrolyte imbalance in bats, is associated with high mortality rates of several hibernating bat species in North America. Aside from restoring water balance, hibernaculum water sources may also provide minerals to bats, which could contribute to restoring electrolyte balance and reducing the impacts of WNS. However, hibernacula water sources may also be a source of toxic elements, such as heavy metals. We collected water samples from 12 hibernacula in New Brunswick, Canada, and determined the concentrations of 18 elements in each water sample (n = 103 samples). Aluminum, barium, calcium, chloride, magnesium, manganese, potassium, and sodium were the most common elements detected, with concentrations of aluminum, lead, and manganese above drinking water recommendations (developed for human consumption) in some samples. The concentrations of electrolytes in cave water were orders of magnitude below therapeutic concentrations. Sampling period (early hibernation, late hibernation) did not affect results, but water profiles differed among sites and sample types within a site (running water, standing water, ceiling drip, and ice). The water profiles we recorded in our study suggest little potential for secondary consequences of drinking water, whether positive (i.e., electrolyte or mineral supplementation) or negative (i.e., heavy metal contamination). [ABSTRACT FROM AUTHOR]

Pseudogymnoascus destructans (Pd) causes the fungal disease white-nose syndrome (WNS), which has led to high mortality in some hibernating bat species in eastern North America. The ability to detect viable Pd in hibernacula is important for understanding the role the environment plays as a reservoir for infectious Pd. Previous studies have generally used the high-sugar medium Sabouraud-dextrose (SAB) and have had low yields of viable Pd from environmental samples of Pd-positive hibernacula. While cultureindependent methods (i.e., molecular genetics) have previously shown much better success in detecting Pd, these methods cannot determine viability. In 2012 and 2015, we swabbed walls in four hibernacula with WNS-positive bats in New Brunswick, Canada, and cultured the samples using dextrose-peptone-yeast extract agar (DPYA), SAB, and Malt extract (MEA) media. Samples cultured on DPYA produced viable Pd 43.7 to 50.0% more frequently than SAB, with a maximum overall return for DPYA among sites of 62.5% Pd-positive samples over both years. During the initial outbreak of WNS in our study region, Pd-positive swabs were produced from 40.0 to 83.3% of samples on DPYA, whereas SAB produced a maximum of 40.0%. At one site we detected Pd from 83.3% of swabs cultured on DPYA and 0% on SAB. MEA produced no viable Pd. Our figures for Pd detection are as high as or higher than previously published culture-independent methods, while also confirming the viability of the Pd present. We found that the yield of viable Pd from hibernacula walls decreased from 2012 to 2015 as the hibernating bat population decreased due to WNS mortality, but patterns varied amongst hibernacula, and overall, were not statistically different. It is possible that environmental growth of Pd contributes to its persistence within hibernacula. We suggest that future studies on the environmental persistence of viable Pd discontinue the use of high-sugar media that lack inhibitory fungal growth ingredients, such as SAB and MEA, as they favor fast-growing fungal species that overgrow and mask slowergrowing fungi such as Pd. [ABSTRACT FROM AUTHOR]

The introduction of Pseudogymnoascus destructans (Pd) to North America, agent of white-nose syndrome in hibernating bats, has increased interest in fungi from underground habitats. While bats are assumed to be the main vector transmitting Pd cave-to-cave, the role of other fauna is unexplored. We documented the fungi associated with over-wintering arthropods in Pd-positive hibernacula, including sites where bats had been recently extirpated or near-extirpated, to determine if arthropods carried Pd, and to compare fungal assemblages on arthropods to bats. We isolated 87 fungal taxa in 64 genera from arthropods. Viable Pd was cultured from 15.3% of arthropods, most frequently from harvestmen (Nelima elegans). Fungal assemblages on arthropods were similar to those on bats. The different fungal assemblages documented among arthropods may be due to divergent patterns of movement, aggregation, feeding, or other factors. While it is unlikely that arthropods play a major role in the transmission dynamics of Pd, we demonstrate that arthropods may carry viable Pd spores and therefore have the potential to transport Pd, either naturally or anthropogenically, within or among hibernacula. This underlines the need for those entering hibernacula to observe decontamination procedures and for such procedures to evolve as our understanding of potential mechanisms of Pd dispersal improve. [ABSTRACT FROM AUTHOR]