USGS announces cause for WNS

[hewhocaves]

Last night John Tudek posted:

The evidence that it was a bat that brought it is circumstantial only.. It goes along this line:
1. New York City is the closest, largest port to Europe.
2. Albany is the closest regional distribution center to NYC.
3. Containers aren't opened until they reach a regional center (and are split up into smaller shipments).
4. In the years following 9/11, monitoring of imports dwindled (with a low in about 2005, coincident with the exposure of bats (which manifested in Feb 2006).
5. Commercial caves are frequently the most photographed, leading them to be preferentially selected as the initial site. (which means it may have been in a couple other caves, but there is no documentation).

Just to clarify: The Hudson River is dredged 30 feet deep to the Port of Albany, which receives 60 or 80 ocean-going ships a year. From there it's 33 miles to Howes Cave. So a European bat could have jumped ship and flown to Howes Cave.
The bats with WNS in Feb 2006 were photographed by a caver in the old Howes Cave section, downstream of the Howe Caverns tourist operation. Always-on exhaust fans move air from the tourist section into this downstream section. There are some gaps around the fans but it's unlikely that a bat would fly into the tourist section, let alone be touched by a European tourist with G.d. spores.

Thanks for that bit of (often overlooked) info, Chuck. I had suspected that to be the case, but was not certain.
If I recall correctly, Howe's Cavern has a downstream, wild entrance. Also, the reason for the exhaust fans are that the downstream entrance opens into a (possibly still active) quarry. At one point in the Howe Cavern history there was blasting in the quarry that went awry, sending noxious fumes towards the commercial cave and (I believe) killing 2 employees. This was due to the chimney effect in a cave with two entrances. Ever since then, the cave management has pushed all the air downstream.

Hazel,

thank you immensely for taking time out of your very busy schedule to clarify those points and give us some additional insight into the process. The Mycology paper sounds interesting as well. I will put it on my reading list. Cavers, like all biological creatures, adapt to their surrounding environments. :) Kicking and screaming, we adapt. lol.

John Tudek

[Buford]

My thanks to:
Cheryl Jones for alerting me to this thread via TAG-Net;
Amy (Sungura) for providing the link to the pdf version of the Nature article;
Amy (Sungura), John Tudek, Ron Miller, and John Lovass for their comments on what the research shows and does not show; and
Ron Miller and Hazel Barton for justifying my on-going abstinence of TAG caving for fear of bringing Gd spores back to subtropical Florida where nearly all of my caving now occurs.

BTW, when we respond to prejudiced individuals, we allow them to control us.

I would like to put in a strong recommendation to look at WNS factors within the geographically gray area lying between the Southeastern and Mid-Atlantic states. A current hypothesis is that Gd may not be lethal in some Southern states (and the tropics) due to it being unable to maintain virulent infections in relatively high-temperature environments. Is that really true, or only partially so? If so, is it possible that Gd exists as an ordinarily non-lethal pathogen within the gray area? If so, could this allow bats, over multiple generations, to evolve some immunity to Gd via genetic drift? If so, could bats in the gray area provide a genetic reservoir for repopulating the North?

On the other hand, I expect that Gd will also undergo genetic drift within the gray area. Biological arms races are the rule rather than the exception.

This wildlife biologist is every bit as interested in what goes on at the epizootic front as what is happening and has happened behind the lines.

A third avenue for suggested research is to assess the potential for artificially introducing Gd resistance from European bats into susceptible North American bat species via gene manipulation and/or hybridization plus back-crossing.

[BrianC]

A current hypothesis is that Gd may not be lethal in some Southern states (and the tropics) due to it being unable to maintain virulent infections in relatively high-temperature environments. Is that really true, or only partially so? If so, is it possible that Gd exists as an ordinarily non-lethal pathogen within the gray area?

I believe that Ellisons (the most potential cave to see possible spore infection due to many different cavers from all over the world) has shown zero Gd spores when samples were taken. Though your hypothesis seems very relevant, nothing has happened as of yet.

[tncaver]

Buford wrote: "BTW, when we respond to prejudiced individuals, we allow them to control us".

Science is great when it is properly interpreted. Unfortunately there are many scientists and others who twist their results to fit their plan.

[DeanWiseman]

My thanks to:

You're welcome, Buford...

By the way, you should read this article as it deals directly with many of your questions about distribution:

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0019167


This is really the best data I know of relevant to your questions.


With regard to your bat breeding idea. Other than keeping Mexican Free-Tailed bats in captivity at a facility near Carlsbad Caverns, in New Mexico (http://en.wikipedia.org/wiki/Bat_bomb)--which I doubt bothered to breed them since they could just go collect from the untold millions roosting nearby, I haven't heard of any serious efforts to breed, much less cross and back-cross, bats in captivity. I could imagine the occasional captive breeding pair, perhaps. I found a couple places which have fruit-eating bat colonies... but insectivorous, prove me wrong, but I'm guessing no.

-Dean

[Pippin]

I would like to put in a strong recommendation to look at WNS factors within the geographically gray area lying between the Southeastern and Mid-Atlantic states. A current hypothesis is that Gd may not be lethal in some Southern states (and the tropics) due to it being unable to maintain virulent infections in relatively high-temperature environments. Is that really true, or only partially so? If so, is it possible that Gd exists as an ordinarily non-lethal pathogen within the gray area? If so, could this allow bats, over multiple generations, to evolve some immunity to Gd via genetic drift? If so, could bats in the gray area provide a genetic reservoir for repopulating the North?

Anyone interested in this question should try to attend the Tennessee Bat Working Group meeting at Fall Creek Falls State Park on Friday, Nov. 18. A group of researchers with the University of Tennessee is currently working on some very interesting and elaborate computer modelling to try to predict where WNS will spread. I talked to one of the main researchers at a meeting last month and he's predicting a temperature barrier in middle Tennessee, around the I-40 corridor. Of course, who knows if that will turn out to really happen. There are several caves in north Alabama that are extremely cold in the winter (39-40F) that would still be ideal for WNS. I'm certainly hoping he's correct! By the way, the TNBWG meetings are always really interesting, they're a full day of presentations about all sorts of bat research in the state of Tennessee that includes lots of WNS research, but some non-WNS research too. I think the meeting starts at 9:30. I'm sure the Nature study will be a very hot topic of discussion.

[tncaver]

I talked to one of the main researchers at a meeting last month and he's predicting a temperature barrier in middle Tennessee, around the I-40 corridor. Of course, who knows if that will turn out to really happen. .

Unless I am mistaken, infected bats have already been found in Camps Gulf Cave which is well South of I-40. Forgive me if my information is incorrect, as there are many on this forum who chose not to discuss anything with me or share important information because I'm not one of "them". "Them" meaning biologists, or other speleo-technical self perceived aristocrats, all of whom dislike common sense, although they need all of it they can get to accurately interpret their data.

[Pippin]

He said "around" the corridor, or generally middle Tennessee. I haven't seen a presentation on his current research yet, I suspect he'll give a presentation at the TNBWG meeting.

[Buford]

Adding non-Florida germplasm to that of the so-called Florida panther has significantly mitigated some of the adverse effects of genetic bottlenecking in this remotely isolated subpopulation of the cougar. But that is not the same as crossing European bat species with North American bat species. Certainly, it would take quite some time and money to perform hybridization in order to add Gd immunity to NA bats, and then back-cross those hybrids with NA bats to restore something close to the original NA bat genomes; thus my suggestion of it as only a third (or fourth, or fifth) alternative. Actually, I’d rather employ genetic modification despite the sentiments of the anti-GM crowd.

It would be nice to attend the Nov 18th TNBWG meeting, but it is a 12-hr drive one-way, would cost a lot of money, and the subject is not in my area of familiarity. Nor does it address what might be happening in the gray area, which is my primary concern at present and, I believe, addressable only through primary data collection.

I confess that I have a prejudice (yup, I have ‘em too) against computer modeling of potential changes in wildlife populations. Population dynamics are quite complex, requiring modelers to simplify forcing functions, storages, energy and materials flows, etc. Obviously, they must also ignore the effects of unknown factors (which might be discoverable via data collection). Also, models are not necessarily scalable, so models tend to approximate outcomes over relatively short time periods, small geographical areas, and single climate zones.

Of course, my discussions here are loaded with categorical statements to which numerous exceptions can be found, but a similar situation illustrates my points. A few years ago, a group of wildlife agency researchers developed a model of the potential for exotic python species to expand their current South Florida ranges, and determined that at least one species might range as far north as the Mid-Atlantic States. A more recent study conducted winter cage experiments, incorporating that data and a few additional parameters into their new model. They concluded that these pythons’ ultimate geographic ranges probably would be only South Florida and possibly south-central Florida. Does anyone care to guess what the next generation of data collection and modeling might show? Let’s not lose sight of the fact that modeling is iterative.

An interesting observation of the second study was that pythons that were smart enough or lucky enough to seek underground shelter during winter freezes could survive and reproduce the following year. But pythons that were artificially given shelter or heating pads during cage experiments were not smart enough to utilize them! Only a minority were lucky enough to accidentally use them. How does one estimate the percentage of pythons that will spend the winter deep enough underground? How does one model the propensity of pythons to evolve enough smarts to seek underground shelter?

However, there are indeed excellent uses for such computer models. For example, they can be used to determine which known factors might be most important, and to indicate where data collection efforts might best be spent. Likely, TNBWG modelers were aware of this at 0630am this morning. Personally, I like scientists. They continually show me that, even though I sometimes think I am in the vanguard of an issue, I am not even in the second or third wave, and that gives me a great sense of relief. Whew! Now I can stop worrying and go out and play because I know that qualified people are dedicated to unraveling these mysteries. Thus, my prejudice isn’t against computer modeling per se, but against its wrongful interpretations by naïve persons.

[PYoungbaer]

Hi, Everyone,

I am currently attending the North American Symposium on Bat Research (NASBR) in Toronto where most of the prominent WNS researchers are attending, including many of the authors of this paper and many other current studies on WNS. There have been numerous presentations and posters on WNS, including an all morning plenary session today. The conference continues through tomorrow. On another thread I posted links to all the abstracts, for anyone interested.

The full paper has been posted on the NSS WNS website under Breaking News:

http://www.caves.org/WNS/nature10590.pdf

The Mycologia paper and other research is also posted there for reference.

I was pleasantly surprised by the five pages now of comments on this paper. Specific kudos to Ron Miller and Hazel Barton for astute and level-headed analysis of the publication. There is much more new WNS information coming out of this conference, and I will be posting a detailed summary once the conference is over.

A teaser: yes, we can say Geomyces destructans causes WNS, which was presumed for a long time. However, we still can't quite say how. Science attempts to isolate questions and then answer them. That's what is clearly ongoing. Those who wanted this "done three years ago" may not have an appreciation for the challenges in doing so.

Dean: the Hicks/Darling study on bats exposed to previously-affected caves has not been published, but was presented orally following the abstract referred to earlier. That's all the info anyone has on that subject.

Another teaser: Buford: two presentations at the conference - one from Europe and one from the U.S. show it unlikely that WNS will spread to the South - as many of us have suspected for some time. Again, more details on all of this later when I return home and can write it up.

[Buford]

Thanks for that, Peter. Now allow me to press my luck. We discuss European bats and Gd. I worried a little about Gd when I visited some caves in Taiwan earlier this year, so I would be interested in any other Gd news re the rest of the Old World, and especially Eastern Asia.

[Buford]

Here are a couple of interesting paragraphs [and my brief comments] from the PLoSOne article entitled “Pan-European Distribution of White-Nose Syndrome Fungus (Geomyces destructans) Not Associated with Mass Mortality” (references omitted):

“The wide distribution of G. destructans in Europe and the absence of associated mortality supports the hypothesis that G. destructans has co-evolved with European bats and only recently arrived in North America where it is causing unprecedented mass mortalities. Alternatively, G. destructans could have been present on both continents and a virulent strain could have evolved in North-America. Until the relationships between G. destructans populations across continents are clarified, precautions should be taken to minimise the chances of transcontinental movement of viable G. destructans.”

[So, it's too soon to blame shipping.]

“Phylogeographic studies of European bat species have shown that in the last 100,000 years, some species colonised Europe from Western Asia, including Myotis blythii, which has been found with G. destructans. Assuming that G. destructans can be transported over long distances by bats, we speculate that the distribution of G. destructans is probably not limited to Europe and possibly extends eastwards into Russia, Western and Central Asia. Further surveys are necessary to clarify the global distribution of G. destructans.”

[Hopefully, Peter will hear some clarification on this issue.]

[DeanWiseman]

I've been chewing over what a follow-up experiment would have to be regarding the "1.3cm" experiment (#3 on the list shown previously):

Same experiment, only you include some kind of protocol to quantify spore dispersal between the WNS-positive and WNS-negative enclosures. What you don't know from experiment #3 is how many, if any, spores made it through the cage.

-Dean

[hewhocaves]

I've been chewing over what a follow-up experiment would have to be regarding the "1.3cm" experiment (#3 on the list shown previously):

Same experiment, only you include some kind of protocol to quantify spore dispersal between the WNS-positive and WNS-negative enclosures. What you don't know from experiment #3 is how many, if any, spores made it through the cage.

-Dean

Yep... there's lots of other experiments that could be done to clarify point #3. its a great thing about science - there's always another question to ask.

Buford - true. My suggestion relies on the assumption that it is an invasive species form Europe. Its an assumption an di worked out my scenario specifically to show an alternate route of tansmission to the (in my opinion, poorly constructed) tourist transmission path. I only argue that of those two options (assuming it is an invasive species) mine is more logical. That doesn't make it right. Just cause something was supposed to happen, doesn't mean it does. Ask the Texas rangers lol

Spent an interesting night with caver-friends talking about this paper and giving back story as best as I can. One of the most interesting things I observed is how easily many people make the jump from its difficult to spread WNS via airborne processes to its impossible. It gave me reason to be less exuberent about it and to explain that while the airborne route is less likely, its only been shown in one experiment. That's a great thing about talking to people as opposed to message boards - the feedback is so much more immersive.

[DeanWiseman]

One of the most interesting things I observed is how easily many people make the jump from its difficult to spread WNS via airborne processes to its impossible. It gave me reason to be less exuberent about it and to explain that while the airborne route is less likely, its only been shown in one experiment. That's a great thing about talking to people as opposed to message boards - the feedback is so much more immersive.

Well it's one of those things that needs to be put into perspective. I look at is as an encouraging sign, not as a vindication. What I don't like people saying is that the experiment "doesn't tell us anything." Each experiment is like a little arrow indicating an answer to a larger question, and it is our job (you, me, all interested people; not just Dr. Blehert's or Dr. Barton's job) to figure out which which way most of the arrows are pointing. Put in context with all the data regarding the pattern of spread, the history of the outbreak, and what we DO and DON'T know, this arrow reinforces a hypothesis that WNS is harder to spread than what some people may think. A hypothesis and an opinion. Not a theory, and definitely NOT an established fact. Someday... if we're lucky.

Look at it this way... what if the results from experiment #3 showed 85% of the non-infected bats came down with WNS? Who would be saying what then? And what would I be saying? I'd be bummed, big time...


Perspective, people.

1.) Decon your stuff... ALWAYS

2.) Respect the cave closures

3.) Stay active, stay engaged, and don't let people put words in your mouth. Doubt is just a part of the scientific process.

4.) Opinion is not fact.

5.) Challenge opinions if you think the data do not support it. And challenge prejudice everywhere.


-Dean

Dean A. Wiseman, Ph.D.
Research Assistant Professor
Indiana University School of Medicine
NSS#32690 RL
Member, NSS Board of Directors