Stories like this always seem to end badly. But they keep happening:
Imported red fire ants have plagued farmers, ranchers and others for decades. Now the reviled pests are facing a bug of their own.Researchers have pinpointed a naturally occurring virus that kills the ants, which arrived in the U.S. in the 1930s and now cause $6 billion in damage annually nationwide, including about $1.2 billion in Texas.
The virus caught the attention of U.S. Department of Agriculture researchers in Florida in 2002. The agency is now seeking commercial partners to develop the virus into a pesticide to control fire ants.
The virus was found in about 20 percent of fire ant fields, where it appears to cause the slow death of infected colonies. (AP)
I don't like fire ants. Besides my animus, they have other things not-going for them: they eat crops, damage wiring, hasten soil erosion, for starters. They seemed to have no natural predators here (until this virus) and thrive much better in North America than in South America where they are a native species. Now they have moved as far north as Virginia.
On the other hand . . . Unfortunately there is always an "other hand" in the natural world.
The fire ant isn't all bad. As omnivores, they eat just about anything and can reduce tick populations in pastures and yards. Also, cotton and sugarcane growers see them as helpful. The ants munch on boll weevils, caterpillars and sugarcane borers.
'But on balance they're an ecological disaster,' [Mike Merchant, an agriculture extension entomologist] said. 'The good that they do is far outweighed by the negative.'
I'm glad Mr. Merchant has made that balance for us. The bit question if Nature will strike the same balance.
'Certainly, we are excited about it,' said Bob Vander Meer, the leader of the USDA research team in Gainesville, Fla. 'I think the virus has great potential. No question about it.'
[snip]
Integrating the virus into ant baits could offer a tool to the pest-control industry, agricultural producers and harvesters, consumers and others for whom fire ants are a persistent problem.
The virus isn't alone in the fight against the fire ant. In South America, they have dozens of natural enemies. But researchers don't know whether those predators could be introduced here.
Among them is the small phorid fly, which seeks out fire ants and lays its eggs on them. The eggs hatch into tiny maggots that bore into the heads of their host and feed on its brains.
'The problem is we really don't know how effective these phorid flies are going to be in North America,' Merchant said.
They're excited about introducing bait with insect virus or a new species of phorid flies into the environment. And I agree it is exciting. . . "exciting" as in, "these stories always end badly."
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This reminds me of an evolutionary biology I was told (read= may get it wrong, but idea is the same). Rat poison was introduced in the UK and found to be effective as measured by the dead rats. Rat populations went down, but never out. Much head scratching occured. It was found out later that the rats attacked a certain protein that was found to be connected to vitamin K (fuzzy details). The result...? The rats that needed low vitamin K, but were highly susceptable to rat poison died often. The rats that were immune to rat poison but could not absorb vitamin K (fuzzy details) were also relatively low in the population.
The rat population morphed very simply by a couple rounds of sex into the heterzygous of the protein that was highly resistant to the poison and had to consume considerable more vitamin K. I do wonder what the red ants will consume more of when the adapt to the virus. I'm taking a wild guess, but I doubt anyone has actually investigated this.
/sigh.
edit to above:
This reminds of an evolutionary biology ^story^
It was found later that the rat *poison* attacked
I had a similarly skeptical response when I saw an article about this. My guess is the best outcome we could hope for is a temporary reduction in fire ant numbers. After that, we'll simply have selected for the virus-resistant ant strains, and we'll be back to where we were.
Assuming, of course, that introducing the virus doesn't have any unexpected consequences. 'Cause that never happens, right?
Yeah, my first thought was, "So, what else does that virus infect?"
There has to be a decent way to systematically test what else the virus kills... If most insects are immune, I can't imagine this being worse that the toxic chemicals being sprayed in bulk on lawns across America
http://pmep.cce.cornell.edu/profiles/extoxnet/haloxyfop-methylparathion…
Chronic NOEL levels of 50 mg/kg for rats and 3 mg/kg for dogs have been reported
"Hydramethylnon is toxic to fish (4). The 96-hour LC50 for hydramethylnon in rainbow trout is 0.16 mg/l, 0.10 mg/l in channel catfish, and 1.70 mg/l in bluegill sunfish (1).
Hydramethylnon accumulated in bluegill sunfish at 1,300 times its concentration in surrounding waters (4). "
or this one....http://www.pesticideinfo.org/Detail_Chemical.jsp?Rec_Id=PC34806
lethal to fish, amphibians, and prett much people too....
sprayed onto lawns at 1/3 pound/100 gallons
Robert: You are probably right . . . except that chemicals don't reproduce.
About those phorid flies. I have no idea what they are, or much of anything relating to this. Except...
I had a friend doing research on controlling invasive species (in her case, some plants from abroad that are taking over around this area, and that are *still* being introduced and spread by ignorant gardeners) with imported insects and the like.
Yes, these projects can go badly and spectacularly wrong. And they know it. The people trying to control invasives obviously know just exactly how devestating invasives can
be, and they spend decades doing research to see what the possible effect/outcome of yet another introduced species would be. The choice to weight what is worse: to let an invasive run wild (known bad), introduce a predator and risk who knows what (potential bad), or just hope for alternative controls (complete unknown).
I've seen a TV show on the phorid fly experiment. It works very well except for the fact that the phorid fly is less robust to drought than the fire ants. In a dry year you lose all the phorid flys before they can wipe out the ants.
They don't wipe the ants out completely but do decrease their populations and rate of spread.
I have four mounds in my back acres. They will go under the dry ice bomb in about a week. Yes Revere they have their uses but there are other ants that have more use than these guys. Dry ice under a sheet of plastic or blanket generally ruins their day. I cant find any real use for them myself. I wonder if thats the same virus that might be infecting the bee population?
mrk-- the bees have enough problems of their own, though I wouldn't rule it out. When I started keeping bees 15 years ago the only things I had to deal with were predators like skunks and raccoons and the harsh midwest winters. Then came varroa, and tracheal mites and gradually if I wanted to find live hives in the spring, I had to poison them in the fall-- low levels of pesticides to kill the mites, medication for the varroa, "preventative" anti-biotics to kill whatever attacked them when they were weakened from the other crap. It took careful drug withdrawal times, and several openings of the hive at a time of year when the weather is usually not helpful. My bees died out about 5 years ago after I decided it really couldn't be done organically. I was waiting for the bee breeders to come up with resistant lines that didn't require medication. Poor, sweet things-- opening up what in the fall had been a bustling hive bursting with well packed honey and 40,000 bees to find only rotting bodies and mice is as bad as finding your dog dead on the road.
In Asia, where I live, folks dig up the nests and eat the ants' eggs. They're pretty tasty - and a natural way to keep down the populations of insects.
I'm all for killing fire ants. I would like to see them entirely exterminated in North America. However, I have doubts about anything actually being able to do it, unintended consequences aside.
I agree, Revere, these stories always end badly. I think the old saying, "Be careful what you wish for, you may get it," probably is appropriate here.
I think that Fire Ants would like to see us eliminated from N. America too.
In Australia we have two vitrus introductions that haven't ended badly.
Myxomatosis was introduced in the 1950's, massively reduced the (introduced) rabbit population, and while there is substantial resistance to myxomatosis, the rabbit population is still far below the 1940's levels. Rabbit calicivirus was introduced in 1995, and has pushed levels down again, and especially helps in arid regions where myxomatosis lacks vectors. These aren't eradication, and myxomatosis effectiveness dropped, but they've had no negative effects to my knowledge.
I understand that USA fire ants are in supercolonies of closely related ants. This may help delay the development of resistance, because there is less genetic diversity than in natural populations, although Australia's rabbits are also derived from a small initial population.
Just say "cane toads" and "rabbits." (Australia)
Randolph K has the right solution here: find the mounds, cover with plastic, add dry ice, and the cold CO2 gas will percolate down through the tunnels and suffocate the colony. This is only useful near human habitations or other areas people can see and get to, so it won't get the colonies in the woods and so on. However in time a natural local predator should arise and keep these little buggers in check.
In the long run, the answer to invasive species and intercontinental infectious agents is simply to cut way back on all this global shipping of unnecessary goods, and global travel for unnecessary purposes. Fifty years ago we did not need fruits & veggies from halfway around the world; people got along fine without 'em. Fifty years ago we did not need casual vacations to exotic destinations, people got along fine with a small summer cabin built by an extended family and shared among its members. Modern consumerism is the greatest excuse for irresponsibility, and the biggest cause of preventable crises & catastrophes, the world has ever known.
..." cut way back on all this global shipping of unnecessary goods, and global travel for unnecessary purposes. Fifty years ago we did not need fruits & veggies from halfway around the world; people got along fine without 'em. Fifty years ago we did not need casual vacations to exotic destinations, people got along fine with a small summer cabin built by an extended family and shared among its members. Modern consumerism is the greatest excuse for irresponsibility, and the biggest cause of preventable crises & catastrophes, the world has ever known."
Well said, g510.
Applicable to the pre-panflu year period we're in, too.
We need to make societal economic and personal changes and set things up differently, before Mother Nature and the Gods of the Copybook Headings come with the clue-by-fours; "bonk-bonk on the head".