The Bats and the Bees - Hidden Heroes of Agriculture in Danger
I've reported on the precarious health of bee populations in Washington State, and bee colony-collapse disorder has received worldwide attention because of the irreplaceable role that honey bees play in the pollination of agricultural crops. Just last week scientists announced they were beginning to understand the combination of fungal and viral infections in bee colonies that are leading to widespread collapse.
Apparently bat populations, natures most important pesticide, are also under siege;
For several years now, scientists have been sounding alarms about a devastating fungus, White-Nose Syndrome (WNS), that has literally decimated bat populations in the Northeastern U.S. The fungus leaves a white substance on the bat's nose, wings and body, and disrupts the bat's hibernation patterns, forcing it to burn through its fat reserves, which quickly leads to starvation. Earlier this year, a survey of the bat population in New Jersey estimated that 90% of that state's bats had been killed off.
I didn't really have bats on my radar as virtuous creatures of the night, but their role in the food chain is amazing;
Bats are the primary predator of night-flying insects. That not only includes pests like mosquitoes but also insects like corn earworm moths and cotton bollworms. In their caterpillar forms, those insects can destroy crops. A 2006 study of several counties in South-Central Texas concluded that the local bat population had an annual value of over $740,000 a year as a pest control -- or up to 29% of the value of the local cotton crop.
A bat eats 60% to 100% of its body-weight in insects every day. Adams says one colony of Mexican free-tailed bats in Colorado's San Luis Valley, an important agricultural region, "pulls about 100 metric tons of insects out of the air in a year." And having bats in agricultural areas, he says, tends to move insects out of those areas, creating less need for dangerous and expensive pesticides.
This is a good reminder to me of the interconnected web of nature. We tend to find a problem in one area and try to fix the problem as if it were isolated. Our philosophical heritage is to imagine the world as a machine, and with a machine when one cog breaks down you can isolate it and fix the one cog to get the machine running again. It would be easy to look at these issues as isolated problems with bees and bats, but they are more likely reflections of systemic problems. While the scientists work on "isolating" the fungus and virus to study it I hope there are some ecologists working on the big picture question of why vital parts of the system are collapsing. Could it be that the over-generous application of anti-fungicides in agriculture is leading to the rise in especially harmful varieties of fungus? Or could it be that regularly covering a good portion of the earth's surface with herbicides like Round-Up is killing some important bacteria that controls fungus populations? It may be completely unrelated but those are some questions that come to my mind.