North America's unknown potential disaster

This is because the bat is under attack by a killer fungus that grows on the bats’ wings during hibernation and causes them to lose body fat and wake early from their sleep, which causes them to eventually die. The fungal infection is said by researchers to be capable of killing off the bat within the next 16 years when their current population, which numbers up to several million, may fall to just 0.01% of present levels.

The study was conducted by a team of scientists led by Thomas Kunz of Boston University. By looking at data collected on the bats over the last 17 years, and travelling around the United States studying bat colonies and common hibernating areas, they found that the population had already been depleted by over 1 million.

Kuntz told North America news media that in some caves and abandoned mines where the bats often hibernate, so many bats had died that the floor was littered with dead bodies, making it impossible to enter the cave.

White-nose syndrome is so-named due to the white fungus that grows on the little brown bats around their mouth and on exposed skin, such as the membranes underneath their wings. The malady is poorly understood worldwide and Kuntz team was one of the first to bring to the attention of mainstream science.

The disease is a vicious killer and spreads rapidly, it was first reported in New York in 2006 and has since then spread to eight other US states including territories as far afield as Tennessee and over the Canadian border into Ontario, where the first signs of the disease were reported in 2010.

It spreads extremely rapidly, in a single colony if one bat becomes contagious, records show that up to 74% of the colony may die. Because of this, the US Fish and Wildlife Service has indicated that there is little that can be done to save the bats’ populations around North America and some scientists have told North American news media that the bats will certainly be extinct by 2026 or 2030 at the latest.

Despite this, governmental wildlife agencies, such as the US Fish and Wildlife Service, have taken steps to combat the disease, calling for a moratorium on caving activities in affected areas, thereby preventing any humans from being legally allowed to enter the bats’ caves, they have also called upon anyone entering any caves in North America to decontaminate their clothing afterwards.

White-nose syndrome is relatively unheard of for most people, but researchers are insisting it is in fact of the gravest concern.

Allan Hicks of the New York State Department of Environmental Conservation has been studying the effects of the disease in New York and calls it “unprecedented” and “the gravest threat to bats ... ever seen”.

The disease is of concern, not only for its impact on the little brown bat and a species of endangered bat (the Indiana bat), but also because of the knock-on effect it may have for the human population. The disease cannot spread to humans, but the eco-systems of North America will become unstable if the little brown bat population dies away.

This is because little brown bats are known to eat their entire body weight in a single day and they feed on a range of insects, many of them pests to the human population, such as mosquitoes and other pests and insects that plague farmers across the region. The current die off of over 1 million therefore means that over 600 tons of insects are no longer being eaten and will therefore proliferate in their habitats, creating a knock-on effect that is passed up the food chain.

However, the long-term prospects are even more concerning, if the entire little brown bat population dies off, if the species becomes extinct or even critically endangered, many thousands of tons of insects will breed without one of their most significant predators to keep their population in check.

This will create a severe problem for farmers and the use of insecticides will need to be increased, creating environmental concerns for the sustained viability of soil and the danger posed by toxic runoff and the effects this may in turn have on other species of animal that may be affected. Also of concern, is the disease-carrying capacity of many bugs such as mosquitoes that will be in abundance without the little brown bat and may infect humans as well as other animals.

Researchers have not yet fully investigated the range of consequences that may ensue for humans, but have unanimously agreed that the outlook would be “dire”.

Investigations are underway to find a colony of little brown bats that have been immune to the disease, bats that are genetically resistant to its effects. It is hoped that such bats may be bred enmasse to rebuild the population. Scientists have also called on humans to provide hibernating space in their homes such as the basement and attic, where smaller numbers of bats can bunker down and thereby decrease the chances of the disease spreading so virulently.

A ‘roost module’ has been designed, which people can put in their attic.

The study was first published recently in Science, a journal that deals with all aspects of the discipline from which it takes it’s name and has since then taken North American news media by storm. It is likely that awareness of this disease and the danger it poses to little brown bats will increase as human learn more about how important they are to the ecosystems of North America.