Discussion of destroying WNS populations

[MUD]

Since you guys already brought it up, I wonder what kind of cows tail Hitler would use to exterminate bats - static,or dynamic?

I really love this forum. Online entertainment at its finest!

[shibumi]

Well first,



Panic logging may or may not have removed resistant American chestnuts. The fact that many more american chestnuts did escape that logging...and still succumbed....tends to make that possibility speculative, American Chestnuts even exist sporadically today...as stump sprouts of long dead main stems, those sprouts ALWAYS succumb once they get a few years old.

I know this is off the main point you are trying to make, but since you are using it to bolster your argument, and
forestry and silviculture is one of my hobbies:

Chestnuts exist today as stump sprouts because they cannot change genetically. So they cannot breed disease resistance.
Regardless, there have been finds of resistant American Chestnuts and these are being cultivated. As far as your
Elm statement, please tell me how long it takes an Elm tree to go from seed to sexual maturity. In the years
since Dutch Elm we've had maybe 1-2 generations, hardly enough time to gain disease resistance in a population.
What is the breeding cycle for a bat?

I respect your education and experience in wildlife management, but I have disagreement with you when it comes to
epidemiology and the control and spread of disease. Specifically, I disagree with a nuclear option without further
data.

[tncaver]

History is very very clear that wildlife pathogens like this are stopped in just 2 ways. Let it kill every individual not resistant to it (so far this seems to be a quite low percentage and might be zero) Or Kill every individual that has been or even might have been exposed you can find so it cant spread.

It would seem that wyandottecaver falls into the category "kill every individual that has been, or even might have been exposed you can find, so it can't spread". Does this mean that Wyandottecaver must sacrifice himself, along with all the bat biologists that might have been exposed?

Now, read what the endangered species act says:

6.302 Wetlands, floodplains, important farmlands, coastal zones, wild and scenic rivers, fish and wildlife, and endangered species.

Endangered species protection. Under the Endangered Species Act, 16 U.S.C. 1531 et seq., Federal agencies are prohibited from jeopardizing threatened or endangered species or adversely modifying habitats essential to their survival. The responsible official shall identify all designated endangered or threatened species or their habitat that may be affected by an EPA action. If listed species or their habitat may be affected, formal consultation must be undertaken with the Fish and Wildlife Service or the National Marine Fisheries Service, as appropriate. If the consultation reveals that the EPA activity may jeopardize a listed species or habitat, mitigation measures should be considered. Applicable consultation procedures are found in 50 CFR part 402.
[44 FR 64177, Nov. 6, 1979, as amended at 50 FR 26316, June 25, 1985]

[Anonymous_Coward]

Panic logging may or may not have removed resistant American chestnuts. The fact that many more american chestnuts did escape that logging...and still succumbed....tends to make that possibility speculative, American Chestnuts even exist sporadically today...as stump sprouts of long dead main stems, those sprouts ALWAYS succumb once they get a few years old.

Yeah, this is what I thought to be true as well until I read the Wikipedia American Chestnut article. If you take the time to read it you will see that in recent years large, mature chestnut trees have been discovered in at least six separate locations across the eastern U.S. These trees are up to 24" in diameter and at least one location includes an entire grove of trees. Some of these trees are now being used as genetic stock for a blight-resistant chestnut hybrid that is slated for re-introduction into forests in 2010! So your statement about sprouts ALWAYS succumbing to the blight does not hold up to factual evidence.

(It's on Wikipedia, so it HAS to be true! It's not like they just let ANYONE write that stuff on there!)

Panic logging being responsible for removing resistant organisms may be speculation, but it does stand to reason. I speculate that there would be MANY more resistant trees to draw genes from had panic logging not taken place. Eventually, some of these bats will show resistance. Let's not send them to the gas chamber before they do.

[Lost]

Bats have been around for millions of years, fungus has been around for as long.

Fungus has been around way longer then bats.

[wyandottecaver]

A discussion of Resistance:

I will discuss the finer points of Elms and Chestnuts in PM with those posters unless people are just captivated by forestry..... But the gist of the arguments at least in part is that by destroying these colonies we would be destroying any individuals present with an inherent resistance to the pathogen who could then repopulate the species or provide insight for study. Lets assume then there is resistance present which is certainly possible.

Assuming there is resistance...which so far has not been shown...the next question is how much is enough? 1%? 5%? 10%? 1%-5% of the population might be enough for trees which are often farmed as clones anyway, though this makes them vulnerable to other diseases... Mammals are a different story. Below a certain point it won't matter if you have resistant individuals because over time the effects of inbreeding will doom them almost as surely as WNS. Bison have been brought back in large part by interbreeding with cattle. The Florida Panther has been crossbred with western strains and still has inbreeding issues...*if* there are resistant individuals could we crossbreed them? maybe...maybe not. Could you do a captive breeding program like has been done for Ferrets and Condors? yes. But at a high cost and to what end? a genetically choked population all the more vulnerable to the next disease?

We can remain passive while gathering info and waiting for more data. During that time we may learn that there are indeed resistant individuals...we may learn more about WNS. But it seems likely that by doing nothing WNS will reach the karst of the midwest by next year or the year after. Without any evidence of resistance at a level that is genetically sustainable (or even at all) it seems an awfully poor gamble to make when we know that reducing the number of infected bats emerging in spring will reduce the opportunities for WNS to spread.

My argument is that the gamble (which it most certainly is) of stopping or greatly slowing the spread of WNS into currently healthy areas by culling is a better gamble than hoping for resistance (or a miracle) and then hoping its enough to matter. I would especially argue that the consequences of failure between these two options favors culling.
several people have said we need more information before destroying colonies....They have said what about resistance?

I would ask What information are we waiting for? A simple, cheap, easily applied, permanent cure we can apply to major hibernacula? Another very big, low probability gamble..... What else could we learn that would matter in time? I'm asking because I cant think of anything. If you argue for resistance show me even circumstantial evidence of resistance at a level that is genetically important...heck at all...until then it seems like we are talking about options that don't really exist.

[George Dasher]

The point I wanted to make (and perhaps I said it poorly) is that everyone is focusing on the fact that WNS can kill up to 90% of certain species of bats.

We also need to focus on the fact that 10% of the bats are surviving. These bats may contain some resistance (or whatever) to the fungus, and this resistence may ultimately allow their species to rebound from WNS. We don't want to be killing all the bats.


When the Chestnut Blight went through, the Government said cut down all the trees--they're all going to die anyway. The thing is, all the trees didn't die, and many blight-resistance trees were probably cut down.

Yes, there are pockets of American Chestnut left, but they are very few and the species as a whole is not rebounding. Of course, it is not helping any that some of those pockets are being cut down for new housing developments.

And, of course, one of the biggest pains about the Chesnut Bight (they were actually two, by the way) is that you would be hard pressed to find a more productive tree, particularly from a rural, poor-people's point-of-view.

[mae]

Okay, it's agreed that wildlife cannot be contained in the same manner as the controlled environments of livestock. So, if one infected bat escapes extermination and meets up with friends in an uninfected environment, what was the point of killing all the other bats? Research that came out recently seems to suggest that by providing a heated place for infected bats their lives can be extended by keeping them from burning off all their fat reserves. Of course the practicality of this is a whole other ball of wax.

Another point that is completely ignored is the fungus that best evidence shows to be the culprit. If the cave environments are contaminated with it, how are you going to get rid of it? Is it ethical to kill everything else in the caves to get rid of the fungus? What about the rights of the fungus? Is it even possible to kill off all the fungus? For all we know this fungus could be all over the caves in TAG right now working it's way to show up in all our bats next winter.

[tncaver]

Killing off ALL of the infected bats might work. But how do you know you are getting ALL of the infected bats?
It is likely there are bats in places humans have not found or can not get to. And what if humans ARE transporting WNS?
Then killing off the bats won't work. You would have to kill off the humans too. What if, what it, what if?
Kill all the bats...impossible. Kill all the fungus...unknown, because the cause is unknown as well as how it gets from
place to place. And btw, those caves in Virginia that are visited so often and have WNS....the bats fly there because it
is their normal place to go. The fact that a lot of humans ALSO visit those caves, does not mean they brought WNS there.
Because there are lots of bats there, it is just as likely that the bats brought it there instead of humans. The bottom
line is still the need for FACTS, not guesses and I think the time for killing ALL the infected bats is long past practical.

[wyandottecaver]

that 90% figure is potentially misleading. First, those 10% that lived may be the last infected this year and the first to die the following winter. Also, they may be composed of healthy bats from another cave that just moved in. The survival rate in multiple years seems to continue to drop. In one cited example a "early" WNS cave that started with 1000+ bats had fewer than 30 this year.

As I stated above, you won't get every bat. But you don't have to. The more you get the lower the percentage chance the remainder will spread it to a healthy cave. Yes 1 infected bat can probably spread it. Then you would have 1 new site instead of 5-15 (plus other unknowns) and you would only have 1 more site to cull the next year. If humans are transporting it you STILL have reduced the spread anyway. The caves already infected may well stay that way bats or not. Those areas almost certainly will remain decimated for decades...or forever. But after a couple years there likely won't be any (or very few) bats left in those sites to carry it anywhere else. and its everywhere else were talking about saving. The VA cave don't mean people carried it there. BUT, a bat going from last years WNS areas VA in only one year...means the circumstantial evidence of people carrying goes way up.

It might have already reached TAG. It might have reached Indiana. The point is to at least try and stop it from reaching places it hasn't.

BTW IMHO the thermal boxes are a sign of "cute fuzzy" desperation. Prolonging the life of infected bats and then letting them out of the cave in spring to kill others is just completely backwards biologically but makes happy news.

[John Chenger]

Folks, consider that WNS is a SOIL FUNGUS that is attacking bats (and -possibly- other critters that hibernate, stay tuned for that) by eating skin and hair below a certain temperature. Killing or washing bats (or a cave or mine, obviously) is pointless.

Also consider it can be carried around by dust particles essentially, any time of the year, on clothes, packs, car seats, the hair on your head. One recent visit to a cave had a large group of people carry gear into the cave in plastic bins, and they changed inside the cave. This cave turned out to be a WNS site with only 10% of the bats remaining since the last survey 2 years ago. Well, since everything was carried into the cave, as it is customary for this particular cave, no one had "clean" clothes coming out, and this was quite likely year #2 for WNS at this particular site, so EVERY OTHER TRIP for 2 years or more was "spreading the love" across the entire eastern US. Even on the most recent trip I guarantee there was dirt on the bottom of those bins that were tossed in the back of the truck.

Finally, consider bats do not necessarily see a collection of caves and mines as individual sites. To a bat, the collection of Carter Caves is really one giant cave site with tons of microclimate options. They WILL check out caves they don't end up hibernating in....so just protecting "known bat caves" give some folks a warm fuzzy but the reality is bats are going to pick WNS up in any of the "non bat caves" they venture into. This is how WNS got into Shindle, a gated site with essentially no human visitation. The bats just went and visited other prime WNS caves nearby, the big picture is clearer now that some other sites have been looked into. I think perhaps a simple flowchart would illustrate this easily at this point, it's not terribly difficult considering initial flash points of WNS in PA and WV also happen to be in the caver tracking database, and VA is the backyard of some incredibly active grottos.

Containment is over. We lost that front a year or two ago before anyone realized there was a front. Yes, it is in KY and TN and probably IN, just hasn't been "noticed" or takes a year or two for the symptoms to start showing. Some knowledgeable folks off the record will tell you they figure it is in "hot spots" all over the country, just undeveloped yet. (Personally, I'm still holding out for no sites to be detected west of the Allegheny Front this year at least). There is no one to blame, it is what it is at this point.

Please note the above is my analysis and commentary and does not necessarily reflect the view of anyone else.

[George Dasher]

I would like to point out that this country is used to "warm and fuzzy feeling" solutions that don't acheive anything.

But, of course, this post doesn't achieve anything either...

[gturner6ppc]

Has anyone tried spraying the bats with a wide variety of anti-fungal medications? If some bats already resist the disease then perhaps the rest just need a little help until their immune system is up to speed.

The fungus doesn't grow well at warmer temperatures, so perhaps we could just turn the caves' thermostats up to room temperature. I'm sure they all have a thermostat somewhere or cavemen wouldn't have lived in them.

As for eliminating the bats in popular caves, that still doesn't help that much because so many caves remain unexplored or seldom visited. One of my college roommates (also an NSS member) had seven or more virgin caves, most of which had bat populations, just on his farm. There are plenty of karst areas that don't get much attention from cavers because the caves tend to be small and rather uninteresting, but which bats find perfectly acceptable. Considering how fast WNS spread down the East, just one of these hidden reservoirs would defeat any "permanent solution."

[MapGirl]

I am by no means an expert in either epidemiology or silviculture, but I did recently read a fascinating article in an Ecology class about the Chestnut Blight and the "panic logging" management plan. Here's a link to it on my home server as a pdf: http://www.unstandardized.com/chestnut.pdf . The main thrust of the article is the connection drawn between the Chestnut succumbing to blight and the extinction of the passenger pigeon that occurred just before the blight set it; the pigeon, with its vast numbers, was the Chestnut's primary source of nutrition. In focusing on the blight, logging firebreaks, etc., the forest managers failed to address the fact that the Chestnut population they were dealing with was, in effect, seriously malnourished, which greatly increased the population's vulnerability. Nobody looked beyond the proximal cause of the pathogen to treat the situation with ecological sophistication; instead we panicked and logged the trees, creating a population with a severely limited gene pool to breed blight resistance.

Reading the research about WNS so far, the situation seems to merit a sophisticated consideration. The Geomyces species is a cold-loving, soil-dwelling pathogen that irritates skin and hair follicles, but the bats are dying with a severely imbalanced digestive system; a lack of enzyme-producing bacteria necessary to process nutrients, erratically spiking metabolic rates, and seriously depleted body fat. All of the bats in the WNS region seem to be losing body fat even before they enter hibernation. If the bat situation is parallel to the Chestnut situation, the best thing we could do might be to attend to the other factors in the bats' lives that affect their health: their nutrition, their various habitats, their vulnerability to predation.

My take on the destroying of populations: I agree with many here that thinking we can actually contain WNS by exterminating all potentially affected bats is fantasy; the quarantine is broken anyway, and we would have to slaughter an awful lot of bats that might hold some chance of being resistant. But the slightly less extreme idea of euthanizing only all visibly affected and collectible bats, bats that to the best of our understanding are doomed anyway by the degree to which they are already affected by WNS, and hoping to therefore slow the spread of the Syndrome and therefore give the rest of the gene pool a better chance to breed resistance (or us a little more time to find a magic bullet) has some sense to it, even if I'm not sure I agree with it. If we knew the individual bats we euthanized were doomed anyway, then all we would be doing would be hastening natural selection. That makes a certain degree of sense. My major logical argument against that is: how will we know what resistance looks like? In Hamilton Cave (I was on the count that confirmed WNS in that cave), the bats posted near the entrance, flying around in February, had no visible fungus on them, but were probably more severely affected than those bats at the back of the cave with fungus all over them - they had simply groomed the visible fungus away. And might a resistant bat not be affected by the fungus for a few years, looking just like a doomed case, but then recover? And also, what if population resistance ends up being behavioral, rather than genetic: bats choosing particular microclimates within their hibernacula, altering their diet, developing a mutualistic relationship with some other creature? That's my logical argument; it's not infallible. My moral argument is: who are we to euthanize these creatures? We aren't their God or their priest or their doctor or their family. We could probably do them, and all of nature, more of a favor by finding a way to drop our own population and get ourselves and our chemicals out of their lives, but that is never the choice we'll make.

So I guess I'd like to offer some conservative respect for the euthanasia idea, but then return ultimately to the hated adage: it's complicated. In nature, things usually are.

[wyandottecaver]

Mapgirl,

your comments are quite valid. Note that I never advocated colony destruction as a way to stop WNS completely other than a slim chance that the "ones that get away" die before finding other healthy bats. but the main point was to greatly reduce its rate of spread by reducing the number of spreaders.

You make the case yourself why a partial euthanasia plan is probably not feasible.

As to the moral argument, I look at this way...We have already come too far to suddenly abdicate responsibility for our environment. I think that even if every pipistrelle, little brown, and Indiana Bat between the Atlantic and Pacific died of WNS then nature would eventually regain a balance...But when I show my kids a picture of a "velvet ceiling" of 10,000 roosting bats before WNS, I sure want to know I at least tried.