Posted on 04/03/2006 8:16:19 PM PDT by neverdem
MISSOULA, Mont. — First came the knapweed. Then came the gall fly. And now the mice population is exploding — the mice that carry hantavirus. In a classic case of unintended ecological consequences, an attempt to control an unwanted plant has exacerbated a human health problem.
Spotted knapweed, a European plant, is a tough, spindly scourge that has spread across hills and mountainsides across the West. In Montana alone, one of the worst-hit states, it covers more than four million acres.
In the 1970's, biologists imported a native enemy of knapweed, the gall fly. The insect lays eggs inside the seed head, and the plant then forms a gall, or tumor, around the eggs. When the larva hatches, it eats the seeds.
Dean Pearson, who works at the Rocky Mountain Research Station of the United States Forest Service, said the fly had not halted the spread of knapweed. In a report in Ecology Letters, however, Dr. Pearson reports that the introduced fly has changed the ecosystem's dynamics.
The fly larvae provide an abundant food source for deer mice in the winter, above the snow. Instead of dying out, as is often the case in cold and snowy weather, the deer mice climb the stalk of the plant above the snow to the seed head. They can eat as many as 1,200 larvae a night, at a time when there is normally no other food.
Mice numbers have tripled because of this food supply, said Dr. Pearson, and with them hantavirus, a viral infection is spread by urine and droppings. It is rare, but can cause a pneumonialike disease that can be fatal to humans.
"It illustrates the complexity of how these things play out in the system," Dr. Pearson said. "These kinds of things are not being considered" when exotics...
(Excerpt) Read more at nytimes.com ...
My allergies are always worst when that purple loosestrife is in bloom, too. It's worse up in Oswego County than around Syracuse but I'd sure hate to see it spread anymore. I've heard that mice are connected with the spread of Lyme Disease, which is not good. Our nextdoor neighbors dog has it and it's out for walks in the woods with it's owner a lot.
Maybe they should do is as a community service requirement for teens who are working off some misdemeanor penalty.
That's the problem when the federal government gets involved in managing land. If it was private land, the weeds would be gone and so would the mice. Nobody would have brought in a bunch of flies or bureaucrats which may end up being the biggest pest of them all. Wonder how many million dollars this bright idea cost us? I just hope that legions of spotted owls don't move in for the mice.
Ray Bradbury is a fantastic author.. most of his stuff is great
True, but the primary predator would be the prairie rattlesnake. Small (fatal bites are virtually unknown) and somewhat irritable, most people don't keep them alive as neighbors...
That's great. I never heard that one before.
It's a fun song and the little kids love it.
The adults like it because it is usually sung by the eldest male in the family...in Yiddish.
I don't know ... that broken twig killed me ... I'm not here.
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