Discussion of destroying WNS populations

[mae]

wyandottecaver, I'm curious if you took environmental ethics in the course of your academic studies, or if you are just an anthropocentric? The comparison of killing bats to rabies control and pathogen containment in livestock fail to convince, because bats with WNS are not a threat to humans and containment of WNS is not a direct economic impact on humans. You also mentioned that livestock slaughtering is an accepted and common practice for pathogen containment, but personally I think we should be moving away from factory farming of livestock and moving towards vegetarianism to lessen our ecological footprint. I am aware that there is an anthropocentric spin on why we should care to save the bats due to their alleged economic impact (that has not been scientifically quantified as far as I'm aware), but I remain unconvinced considering that many insects near human populations seem to be on decline due to pollution, habitat loss, and liberal use of insecticides.

I still have ethical objections to your proposal. If the fungus is a native strain that mutated, it is not our place to try to stop the fungus from killing the bats. If humans are helping to spread the fungus, it is our duty to eliminate this vector of exposure. If humans introduced the fungus to the bats, then it is our duty to try to save the bats. However, I just can't agree to slaughtering bat colonies, because I remain totally unconvinced that such a drastic measure would actually serve to contain the fungus or even slow it down that much, and this is ethically dubious, if you are not a follower of utilitarianism.

I agree that it is not likely that bats will show immunity to the fungus during hibernation, but what about the fungus mutating or evolving into a less harmful strain? I am also not convinced that the fungus is not already in Tennessee, and I do believe that it will be confirmed next winter. Sure you can kill the first couple of WNS populations that are found, but that won't do much if it was already here, especially considering that it is a SOIL fungus. How do you check 10000 caves simultaneously?

[ek]

We know about 90% for sure don't....is a 90% dead dog still a dog functionally?

A dog with 9 dead brothers and sisters is still a dog functionally, yes.

A dog that is not immune to a disease, contracts it, and then recovers is still a dog functionally.

A dog that doesn't contract the disease by chance is still a dog functionally.

I agree with you that the only action we have at our disposal right now that would most likely have a significant impact is to exterminate bat hibernacula. I disagree that it is somehow obvious that the effect of this would overall be positive and have the effect of saving more bats or containing WNS. Killing off individuals that are not resistant per se, but which survive the disease or are under circumstances reducing the probability of contracting it, carries with it an extreme risk if WNS is not effectively contained. Doing what you suggest could ensure the extinction of species that would otherwise survive. This extreme risk is more extreme if there are resistant individuals, but even if not (and yes, it appears there are not...which makes sense assuming that the Geomyces destructans is the infectious agent because in general animals are not resistant to fungal diseases) it is still an extreme risk.

Exterminating large numbers of animals cannot be justified unless there is a clear and compelling reason to believe that its effects will be more positive than negative. And that is not the case here.

Please do not conflate biologists' reluctance to perform an action that is highly controversial because of its extreme risks with the notion that biologists are making a systematic mistake in failing to respond to epidemics. There are many situations where mass extermination is a very bad response to a disease, such as the chestnut blight where resistant trees were systematically killed off along with non-resistant trees. Mass extermination is not the one-size fits-all way of addressing an epidemic that you make it out to be.

wyandottecaver, I'm curious if you took environmental ethics in the course of your academic studies, or if you are just an anthropocentric?

This seems like a false dichotomy and a straw man.

You can take an environmental ethics course and be anthropocentric. You can not take one and not be anthropocentric. wyandottecaver's proposal is not necessarily in violation of environmental ethics--it is possible to make a reasoned environmental-ethical argument for it. I think where wyandottecaver's argument is weak is in its assumption of effectiveness. Whether or not it is acceptable to kill off hundreds of thousands of sentient creatures is a real issue too, but most humans in our society are not particularly bothered by that, and there are many conservation ethics that don't concern themselves with the well-being of individuals or with any notion of rights.

The truth is that bats have an enormous impact on humans, because they eat huge amounts of insects. What level of proof do you require beyond this? I am reminded of Kelly Still's recent example on Cavechat, where she quite rightly illustrates that, for lack of a statistically significant sampling, evidence-based medicine cannot prove that jumping out of an airplane without a parachute is a health risk. In any case, it appears you will soon be getting some proof, because we are "running the experiment" as it were.

Humans may or may not be responsible for WNS. It seems likely that Geomyces destructans is the infectious agent in WNS and that it is an invasive species. The organisms best at facilitating the transfer of invasive species are Homo sapiens sapiens. There is a high chance that humans are responsible for WNS. But even if we are not responsible for WNS, we are responsible for, to put it mildly, royally screwing over bats for many decades, resulting in their reduced ability to cope with any significant threat. Now let's bring the human element into the equation. Fewer bats means crop loss and greater human exposure to deadly bugborne disease. People are going to die. Then we use more pesticides, which may or may not mostly address the problem of the bugs, but which will certainly have an enormously negative impact on the environment. Thousands more species will suffer and many will likely go extinct because of this increased use of pesticides. And here's a more far-fetched, but not entirely unlikely, suggestion: now that WNS has been effectively cultured in cold northeastern caves, the question is whether or not it can survive in warmer karst areas...areas of the world where people are threatened by malaria and/or famine. If WNS can survive in those places and is spread to them by human vectors, then we're looking at one of the greatest human disasters in history.

There are profoundly important human reasons to try to "unnaturally" intervene and stop WNS. I would question not only the ethics of intervening in the specific way wyandottecaver proposes, but also its effectiveness compared to its potential to exacerbate the situation.

[wyandottecaver]

Mae,

yes, I actually took 2 semesters. And either through my inability to explain effectively or your world-view you actually reversed my entire meaning. I wasn't saying we should eliminate colonies based on "human good". I was saying the fact that WNS does not pose a direct health risk to humans is why we have been reluctant to take drastic measures. I argue that what might be bad for the individual bats in WNS colonies (being killed) may well produce a greater good for the species as a whole.

Having people go vegetable would drop our footprint...so would communal housing, birth restrictions, and the removal of a whole host of products. But we also could kill off 90% of people and go back to being hunter gatherers too. Every problem generally has more than 1 solution...some are just better than others depending on your viewpoint. I actually do believe that the earth is here for humans...I also believe we have a responsibility and duty to be good stewards. Ants "factory farm" aphids...is that wrong? We are one of the few species that even concerns itself with the well being of others let alone tries to prevent their extinction. I am saddned by the loss of Passenger Pigeons and Carolina Parakeets. I doubt they would have concerned themselves with our demise.

If I were purely anthropocentric I would argue that every bat in WNS states and border states should be killed and the caves affected flooded with chlorine gas and fungicides to reduce the possibility that this fungus that has already become a lethal epidemic in 1 warm blooded mammal might skip species just like mad-cow did and become a direct human health risk. Serious fungal infections are actually one of the areas that modern medicine struggles with. But only government agencies in charge of caves and caver access would overreact that much

EK,

I agree completely that we do not know if destroying those first new WNS colonies will be effective. We may end up with 10,000 dead bats (or 100,000) and WNS still chugs on as before. We do know that what we have done so far certainly isn't effective as 1/2 to 1 million dead bats proves. In terms of national populations, destroying the first half dozen or so new WNS sites in currently WNS free states is not likely to deal a crippling blow to the overall population size even if we are wrong. If we are wrong and we don't see a effect from destroying colonies then we go back to the drawing board. If we are right, and it does help, then we have 1 more tool to use.

if a bat colony becomes affected everything we have seen says that EVERY bat in that colony has both a high risk of mortality, and a opportunity to spread the disease further. Bats in those locations by default no longer fit into the categories you name like unlikely to contract the disease or do contract it and survive because there is zero evidence that happens. Again, if it doesn't work.... killing those few WNS colonies in the context of all colonies still leaves you with your pool of hypothetical resistance.

Now in those states that are already heavilly affected I see no reason to bother with WNS control 1 way or another. Its there, and thats that. I am talking about states that as yet have no identified sites or perhaps "border" areas where we want to try and hold the line.

as far as risks...that is just my point. There are no identifiable risks at all besides political ones. resistence? no evidence, and if this doesn't work you still have the bulk of the population left where you can cross your fingers. large scale removal of most of the population...thats not what I am advocating. bats in WNS sites already die. I'm just saying kill them sooner in states where it hasn't yet gotten a firm foothold.

As far as mass killing to control epidemics...Chestnut blight is a pretty argument but has holes. If we had left those resistant trees (trees are less dependent on genetic diversity as well so 1% might still be enough to reproduce long term) they may well have not been resistant to the next disease and we would have lost them anyway. What about the economic loss of letting those panic harvested trees rot? In any event trees and insects are much harder to control with a killing strategy than a species you have penned up or that concentrates itself every winter. In fact mass killing is usually the cure for most epidemics....its just the disease doing the killing. My "hope" is that the alleghany mts are effective enough at retarding westward movement that WNS kills off the bats on the eastern edge before an infected one makes it over to our side. The more ugly truth is that WNS probably remains viable in caves devoid of bats and its only a matter of time regardless of what we do, but we should at least TRY.

[mae]

I don't think it was a strawman to ask where wc's moral compass falls. This is an ethical discussion, and I certainly was not accusing wc of being UNethical (I may have indirectly accused him of being a speciesist). An anthropocentricist believes that moral concern is only required for beings capable of moral reasoning. I am an ecocentricist, and to me, the proposal of killing off a colony of bats is on par with proposing to kill off a village of people to stop a disease. I also find the utilitarian view (for the greater good) to be a little morally gray. I hope this clarifies my previous post a little bit.

[dfcaver]

Here in the northeast, we've just got a new disease - well, it's an oldy but a goody. Late blight disease - the old classic Irish potato blight. It's set to wipe out tomatoes, potatoes and perhaps petunias. A fungus spread by air, and needing cool wet conditions to explode. Perhaps introduced on plants from big box stores. Gardeners are asked to disinfect all "gear" with a 20% bleach bath, wash clothing asap, and basically follow the WNS denomination procedures.

The big difference is how the gardener is asked to treat the plants when the disease is spotted. Basically, kill them all, and the first line of healthy ones for good measure. Keep close watch, and keep killing everything that shows an hint of the disease.

Treating "hotspots." A hotspot is a group of infected plants located amid relatively healthy ones. If very little disease is present in the crop and there are only a few hotspots, the latter should be destroyed as quickly as possible by flaming, disking, and burying the infected foliage or killing the plants with a rapidly acting herbicide. Plants immediately surrounding the hotspot should also be destroyed because they are very likely infected even though the infections are not yet visible. If fungicides are being used, the remainder of the held should be treated with a fungicide that has some systemic activity, and subsequently, applications of a protectant fungicide should be applied on a tight (frequent) schedule.

Treating established infections. Once 5 to 10 percent of the foliage is infected it is usually not possible to halt the development or progress of the disease. Currently available (1998) systemic fungicides are inadequate to halt an epidemic at this stage. Only weather that is very dry and hot, both day and night, might temporarily stop the epidemic. Stem infections are very resistant to drying, however, and will sporulate when sufficient moisture is available. Growers can attempt to salvage apparently uninfected tomato fruit but should be aware that some fruit infections will not become visible for several days. Foliage in such fields should be promptly destroyed to prevent spread to nearby fields or farms.

http://vegetablemdonline.ppath.cornell. ... ateBlt.htm

Fungi are nasty.