Myotis myotis – greater mouse-eared bat (Manuel Werner)
- Myotis myotis – greater mouse-eared bat (Manuel Werner)
First discovered in bats in New York State back in 2006, white-nose syndrome has since spread to nine states and threatens to wipe out up to a third, possibly more, of North American brown bats (Myotis lucifugus). As the news of this ecological catastrophe-in-the-making spread across the pond, European zoologists and ecologist braced themselves for the arrival of the fungus in their native bat populations.
Sure enough, in March of last year, European researchers spotted a mouse-eared bat (Myotis myotis) with the white-nose fungus. But to nearly everyone’s surprise, the bat did not succumb to the disease. In fact, so far, most of Europe’s bat species remain largely unaffected by the fungus, and those that do contract the syndrome, are not dieing from it.
Last year, a group of microbiologist from the US Geologic Survey identified the fungus that caused the syndrome as Geomyces destructans which has subsequently been confirmed by European scientists . The fungus was first spotted in a European bat population found in a cave a few hundred kilometers northeast of Bordeaux, France. Since then (March, 2009) three other European nations have confirmed the presence of the G. destructans fungus. So far, however, none of these surveys has reported any deaths associated with the disease.
Two theories or scenarios have been proposed to explain this. The first is that the fungus has been established in Europe for a long time, and thus native bat species have developed immunity or resistance to it. The second explanation is that the fungus evolved into a more lethal form (having greater virulence) after arriving here in the Americas.
Whatever the cause of this resistance in Europe’s bats, it is being viewed as good news by most scientists studying the problem, as it indicates a possible genetic factor at work, which may be revealed upon genetic sequencing and analysis. Such genetic sequencing could reveal more recent changes or mutations in the genetic code of the fungus, or, even genetic variations (“polymorphisms”) in the brown bat. This information will help scientists develop a strategy for eradicating the fungus, or, alternately, for conferring immunity onto the US bats (such as through a vaccine).
Readers may recall my post, early last year (Scientist Develop Heated ‘Bat Boxes’ to Help Sick Bats ), on how scientists have started building heated “bat boxes” to keep the bats warm during winter months when they awaken from hibernation due to the fungus infection. The effectiveness of these boxes is still inconclusive, and, they rely on a chance factor: that the bats will use them upon waking. Developing a vaccine, or other gene-based treatment, will hopefully add to the scientists’ arsenal in their fight to stop the spread and impact of the fungal disease.
Bats, being primarily insectivores, provide an important ecosystem service by controlling insect populations. Some bats that live in desert locales also provide pollination services for flowering cacti.
Some reference material for this post came from a 21 Nov. 2009 Science News Article ‘Europe’s Bats Resist Fungal scourge of North America’ by Erik Stokstad
photo credit: Manuel Werner on Wikipedia (cc-by-sa)
About Michael Ricciardi
