Devastating fungus destroys sleeping bat colonies
In parts of North America, bats are being devastated by a disease that will have a huge ecological effect, white-nose syndrome.
It causes fatalities in 70 to 90 per cent of individuals in an infected bat roost and so far, millions of bats in North America have succumbed to the disease.
Bats are a crucial part of any ecosystem. The ones in Canada are insectivorous, eating huge sums of flying insects and keeping some pest populations in check. If white-nose is left unchecked, it will likely spread throughout North America devastating delicate ecosystems everywhere.
White-nose syndrome is a fungal infection that appears as a white fuzz growing on the bat’s snout and wings. Most recorded deaths due to white-nose syndrome are caused by an interruption of the bat’s hibernation. Bats go into hibernation with a certain amount of stored energy and it has to last until the bugs are back out again in spring.
This fungus is odd in that it does very well in cool weather and that’s where the bats need to hibernate. As such, while the bats are hibernating, the fungus is growing.
The fungus feeds on the skin and causes irritation. The irritation causes them to wake during hibernation, which means a waste of energy as the bats warm up and wake up before trying to go back to sleep. In the winter, wasted energy can’t be replenished due to the lack of food at that time and many bats don’t survive winter.
Even the bats that manage to survive through the winter are weak from fighting off the infection and often die later in the spring.
White-nose syndrome was first discovered in New York in 2006 and has spread throughout the eastern seaboard and further into the continent. In Canada, it has been found in all eastern provinces including Ontario.
The fungus has caused the death of more than 5.7 million bats. The fungus seems to spread slowly as bats come into contact with other bats “next door.”
Recently, white-nose has been confirmed in Washington State. This represents a big geographic jump across the continent and now has the potential to threaten the bat populations in B.C.
One theory explaining the transport of white-nose syndrome is that tourists or cave enthusiasts who have visited infected caves in the east may have accidentally carried the fungus’ spore to a cave in Washington. As of now, no cure for the infection is known but it is a top priority.
The origins of white-nose syndrome are still unconfirmed; however, it is theorized that it may have originated in Europe. Bats in Europe have been able to develop a resistance to the fungus as it is still found in European bats, but does not seem to lead to death. Our bats may eventually develop an immunity, but until then we are likely in store for some big ecological effects first, millions of insect eaters gone.
To prevent the spread of this deadly fungus, experts suggest not going into caves, even ones that don’t have bats. The fungus exists in caves with or without bats.
If the caving is appealing enough to still go, it is recommended that you follow a decontamination process before and after visiting other caves and even your attic if you know you’ve got “bats in the belfry.”
Decontamination can be as easy as using a commercially available bleach solution. Full details on how to fully decontaminate your belongings can be found on whitenosesyndrome.org.
Melissa MacMillan and Jess-C Hall are second year Recreation, Fish and Wildlife students at Castlegar’s Selkirk College.