White-nose syndrome can kill little brown bats: studies
New York, October 21 (SocialNews.XYZ) Two recent scientific studies conducted as part of a project led by the Wildlife Conservation Society (WCS) revealed new information about where and when bats hibernate in their range, and subsequently predict extreme levels of mortality from white-nose syndrome.
White-nose syndrome has already killed over 90% of some hibernating bat species east of the Mississippi.
The disease is the result of a fungus that grows on a bat and damages tissue during hibernation. The fungus grows well in humid, near-freezing environments that bats use for hibernation, the name “white snout” describing the appearance of fungal growth on infected bats.
It usually kills susceptible bats before they emerge in the spring; and the length of hibernation is believed to be a factor that influences who survives. Fungal infection also alters the behavior of bats, so bat survival depends in part on having enough fat to survive the winter, as well as the energy cost of hibernating with the disease. .
Using updated models of the length of hibernation, or when bats hibernate, and relationships between body mass and body fat, Massey University researchers were able to spatially estimate the energy cost of l hibernation with and without white-nose syndrome.
The study, published in Ecology and Evolution, focused on the sensitive little white-nosed brown bat (Myotis lucifugus), which is found across much of North America, and found that the cost Energy from hibernation with white nose syndrome is substantial.
Supporting previous findings, the researchers concluded that the small brown populations that had not yet been affected would not be better than the populations first infected in the East, which were wiped out.
Lead author of the study, Reed Hranac, now a data analyst with the Colorado Department of Public Health and Environment and lead author of the study, said: Colder temperatures in the northern part of the range or warmer temperatures in the southern part of the range would slow the disease process and allow bats to survive. Unfortunately, the energetics suggest that little brown bats will suffer throughout their range. “
This news increases the importance of understanding the conservation needs of sensitive bat species, such as where the species hibernate in winter. Surprisingly, species-level knowledge of where and when bats hibernate has received some attention.
A separate study, published in the Journal of Biogeography, conducted by Conservation Science Partners, took a hybrid approach to answer this question. Instead of estimating winter distributions of five bat species using only land cover and climate characteristics, the researchers added a spatial layer estimating winter survival based on energetics.
Not surprisingly, the contribution of factors such as land cover, winter survival, topography and subsurface features was significant, but the relative influence of these factors varied among species.
The importance of energy-based winter survival in predicting winter distributions indicates that mechanistic energy models of hibernation are improving and being valuable. Additionally, it is promising that there are data-rich landscape features that correlate with winter species distributions, as opposed to underground features that are generally very data-poor.
Sarah Olson, WCS Health Program co-author and project lead investigator, said: “Our unique approach to winter distribution mapping highlights the utility of blending mechanistic energy models of survival with more correlative approaches. traditional methods to map the distribution of species.
“Survival was retained as an important predictor of winter occurrence in the five species studied, showing that physiology can improve our understanding of a species’ environmental niche.”
Improving knowledge of what influences where and when bats hibernate helps address multiple threats such as white-nose syndrome as well as habitat loss and climate change.
Bats are essential to ecosystem health, controlling insect populations, including agricultural pests.