The strong hum and foul stench and cloud of blackness in the air is not a nearby factory or coal plant–it’s a force of nature. It’s the Lake Winnebago lake fly. Every spring, around Mother’s Day, these flies hatch out and fill the air so thickly that you can barely breathe. Even driving alongside the lake requires using your windshield wipers. Every house in the area requires power washing after they’ve died off because their decomposing carcasses are gross and stinky. Fortunately, lake flies don’t bite people since they have no mouth. They’re looking for a place to land, rest, mate and die–trillions do so within 10 days. The second batch hatch out later in the summer and then they disappear for the year.
As much of a pest as these flies are twice a year, they’re an essential part of the ecosystem. The fish love the larvae, as do frogs, bats and birds. The famed Winnebago Lake Sturgeon gets over 65% of their nourishment from the lake fly larvae.
What a fascinating creature–the lake fly only eats while in the larvae stage and hatches into a mouthless fly that lives for about a day–a day that involves having sex and then laying eggs which sink into the water. The larvae play a role in the lake’s ecosystem since they are filter feeders in the water, doing their part to keep it clear of algae and other plant cells.
Lake flies also thrive in a few lake ecosystems in Africa–Enviro-Girl read an unconfirmed rumor that they were imported by a Chicago professor in the 1930′s to encourage the sturgeon population, but other sources indicate the lake fly has been around for over a hundred years. Wherever they came from, the lake flies do their part in their short life to eat the algae and feed the sturgeon. Even pests play a role in nature’s health, and that’s an important thing to remember before screaming for an insect’s eradication. Besides, the lake flies number in the trillions every spring–they’re measurable on radar! Imagine the challenge of getting rid of them–far worse to imagine the lake without them.
Even though I’m shuddering in revulsion, I’m going to do my best not to malign lake flies.