Bat Death Mystery Solved

Gimpy

The Living Force
Bat Death Mystery Solved


Jeanna Bryner
Senior Writer
LiveScience.com jeanna Bryner
senior Writer
livescience.com – Thu Oct 30, 2:16 pm ET

Bats are getting moldy and dying, and this is no Halloween trick. Now scientists have identified the culprit in the deadly mystery.

The killer is a member of a group of cold-loving fungi called Geomyces. This white, powdery-looking fungus coats the muzzles, ears and wings of bats and has meant death for more than 100,000 of the night flyers in the northeastern United States.

"So essentially these bats are hanging on the cave ceiling almost like a piece of food that you've forgotten about in your refrigerator and for whatever reason now they're getting moldy," microbiologist David Blehert of the U.S. Geological Survey told LiveScience.

A big question remains: Why has this murder mystery only surfaced recently?

The fungi live in the soil, water and air, and now on bat skin. They can survive refrigerator-level temperatures, which are typical of many caves where bats hibernate. Once beneath the outer layer of skin covering a bat's wing, the fungus multiplies, sometimes causing the wing to bulge to five to 10 times its original thickness.

The researchers are not sure if the fungus is the sole exterminator of infected bats. Most of the fungus-infected bats are also emaciated and some leave their caves during the cold of winter in search of insect food, in vain. The fungus could be the cause of starvation or it could have invaded the skin of starving bats whose immune systems would have been depressed, the researchers speculate.

The work will be detailed in the Oct. 31 issue of the journal Science.

Mysterious white stuff

Bats covered with the fungus, a sickness now called white-nose syndrome, were first spotted in Howes Cave near Albany, N.Y., during the winter of 2006. At that time, field biologists reported caves that were typically covered with hibernating bats had loads of vacancies, which the scientists assume is because the bats either died or were flitting around in search of food. In one case, a cave floor was littered with dead bats.

Since then, scientists have estimated drastic declines in populations of cave-hibernating bats in Connecticut, Maine, New York and Vermont. In some caves, more than 75 percent of the bats have perished.

To figure out the culprit, Blehert and his colleagues ran post-mortem tests on more than 100 bats from the affected regions. The bats included little brown myotis (Myotis lucifugus), northern long-eared myotis (Myotis septentrionalis), big brown bats (Eptesicus fuscus) and tricolored bats (Perimyotis subflavus).

"We found that this fungus had colonized the skin of 90 percent of the bats we analyzed from all the states affected by white-nose syndrome," Blehert said.

The fungus had invaded deep into the skin of infected bats. The fungal spores likely sneak into the bats' skin through hair follicles or sweat and oil glands. The fungi continue to multiply and push their way through other skin layers until they've broken through the outer layer called the epidermis and reached a layer of connective tissue, the researchers suggest.

And while the fungus is genetically a member of the genus Geomyces, it looks different from the known Geomyces species.

"A typical Geomyces has club-shaped spores and these are curved or shaped like little bananas," Blehert said.

Bat mystery deepens

The caves where bats hibernate from late October through late April or early May in the northeastern United States could be the perfect spots for fungal growth, the researchers say.

Fungi in general do best in moist environments, and so it's no surprise that the researchers found more infected bats in the most humid caves. In addition, this particular fungus can survive at temperatures between 36 degrees and 60 degrees Fahrenheit (2 degrees to 15 degrees Celsius), which are typical in caves.

The bats also lower their core body temperatures to match that of the caves, making their bodies perfect hideouts for the fungi. (In addition, bats lower their heart rates from about 1,000 beats per minute to four beats a minute during hibernation.)

He added, "The bats have done this for millions of years. They have hibernated in these same caves using the same physiological mechanism, dropping their heart rates down, not eating, dropping their core body temperature down, and they didn't used to get moldy."

Why now? The bats may have ingested some environmental contaminant that is causing them to starve, Blehert said, or pesticides may have wiped out their food source, keeping the bats from fattening up before entering caves for hibernation. Their emaciated bodies would then be susceptible to invasion by the fungus.

Another possibility is that the fungal infestation is irritating the bats' skin. The irritation could cause the bats to wake up more often during hibernation. While hibernating bats typically wake up for short periods every two weeks or so, the fungi could cause more frequent wake-ups. These mid-hibernation arousals are costly as the bat warms up its body and turns on other body processes like its immune system. That means the wake-up could use up critical energy in the form of fat reserves, causing the bats to starve.

Blehert plans to continue studying the fungi and its link with bat deaths to get to the bottom of the batty mystery.


Source: http://news.yahoo.com/s/livescience/20081030/sc_livescience/batdeathmysterysolved;_ylt=AuS0qeh2XVj.JskKAkmfl2Os0NUE


**************************************************************************************************************************************


Seems the mold issue is affecting more than just humans. I think the article title is a little misleading, since its still not known why the little guys are getting a fungus no ones seen them suffer from before. Could pesticides be affecting them internally? (How could it not?)

Considering the emergence of fungus on the West Coast, this Eastern report of fungus affecting an animal population is interesting.



Gimpy
 
Bat Deaths Hits 6 Million

The deadly white-nose fungus has killed some 6 million bats in the 5 years since its discovery—and it doesn’t show sign of stopping.

By Hannah Waters | January 19, 2012

In 2006, researchers in New York state documented a strange phenomenon: bats, all with white noses, were dropping dead. In the intervening 5 years, scientists have worked feverishly to figure out what was killing the bats, and identified a single fungus as the cause, but they have yet to find a treatment for the pathogen.

And the news seems to only get worse. Yesterday (January 18), the US Fish and Wildlife Service announced that, according to their recent figures, at least 5.7 million to 6.7 million bats have been killed by white nose syndrome so far in North America.

“This startling new information illustrates the severity of the threat that white-nose syndrome poses for bats, as well as the scope of the problem facing our nation,” said Fish and Wildlife Service Director Dan Ashe in the press release. “We are working closely with our partners to understand the spread of this deadly disease and minimize its impacts to affected bat species.”

Compiling the new figure was no small feat. The pathogen hit suddenly and has since spread to 16 US states and four Canadian provinces, affecting six species. While biologists have extensive population statistics on endangered bat species, data on the common species hit hard by the fungus, such as the little brown bat, are harder to come by.

Federal agencies are now working on establishing consistent data collection methods as part of their white-nose syndrome response plan.

http://the-scientist.com/2012/01/19/bat-deaths-hits-6-million/
 
Deadly bat fungus now in 22 states and parts of Canada

A deadly bat fungus has been spreading across the eastern and middle regions of the United States and parts of Canada. The mysterious fungus has killed millions of bats in recent years.
Approximately 6 million bats have died since a mysterious fungus was first observed in February 2006. The name of the fungus is Geomyces destructans. Digital Journal had reported on this situation in Jan. 2012.
The fungus has now been identified in 22 states and five Canadian provinces, reported Scientific American (courtesy Mother Jones). Primarily it has been found in the U.S. eastern states and portions of the mid-west. Fatality in bats have also been observed in northeastern Canada, going as far west as north of the Great Lakes.
Also referred to as "white-nose syndrome" (WNS), symptoms show in the form of a fuzzy white patch that appears on the noses, wings and hairless parts of a bat's body. Bats affected are hibernating; the fungus thrives in cold conditions. There is a 70 to 100 percent mortality rate.
A new case has been noted in South Carolina for the first time.
"We have been expecting WNS in South Carolina," said Mary Bunch, wildlife biologist with the S.C. Department of Natural Resources (DNR) based in Clemson, in a press release. "We have watched the roll call of states and counties and Canadian provinces grow each year since the first bat deaths were noted in New York in 2007."
Scientists observing the condition are not clear if the fungus is causing the deaths or is a symptom stemming from some other cause. There is no cure and several species of bats are affected.
There have not been any cases in humans or other animals, said the South Carolina Dept. of Natural Resources in its statement. It is said that humans could transport the fungus on clothing, shoes and gear and authorities are asking cave explorers and miners to be careful. Although, experts say bats moving from cave to cave are primarily spreading the fungus, according to a New York Times report last month.
Other effects of the fungus are the impact on the agricultural industry. Media reports indicate since the bats eat insects, studies suggest the loss of bats in North America could lead to a $3.7 billion loss per year in the industry.
Research is ongoing.
"White Nose Syndrome is arguably the most devastating wildlife disease we've faced," Michael T. Rains, Director of the Forest Service's Northern Research Station, said in a recent press release. "Forest Service scientists are conducting research to halt this disease and save bats, which are so important to agriculture and forest ecosystems."
Last month, Digital Journal reported a deadly fungus is also spreading through the world's frog population.

_http://www.digitaljournal.com/article/345615
 
Gimpy said:
Bat Death Mystery Solved


[...]

And while the fungus is genetically a member of the genus Geomyces, it looks different from the known Geomyces species.

"A typical Geomyces has club-shaped spores and these are curved or shaped like little bananas," Blehert said.

Bat mystery deepens

[...]


Seems the mold issue is affecting more than just humans. I think the article title is a little misleading, since its still not known why the little guys are getting a fungus no ones seen them suffer from before. Could pesticides be affecting them internally? (How could it not?)

Considering the emergence of fungus on the West Coast, this Eastern report of fungus affecting an animal population is interesting.



Gimpy

Had never caught that bolded parts before when reading about these bats. It discusses many possibilities, environmental, food sources and such, yet the fungus itself, not being typical, makes one wonder at that causation. You said pesticides could be affecting them, and would not say no easily, especially as their high mortality rates seem to have started off in localized areas (not agra isolated) and have been moving over the years in the rock belts. Nevertheless, when i read it, thought about the changes in characteristics of the fungus to something not seen before, at least they don't pin point it. As such, could not also think of the word "pestilence" as described in C&tHoM as being an influence. :/
 

Trending content

Back
Top Bottom