Weird Bugfest

[mewickham]

I stumbled upon an interesting phenomenon in a water-filled ditch along a hiking trail. I saw a black film floating along the surface, the entire length of the 50-foot stream. It was only on one side, as if wind blown or washed to shore. It looked a lot like an oil slick blown to shore. But closer inspection revealed it to be a surface film composed of tiny oblong dots, about 1 mm in length. Closer examination-- I stuck my finger in to see what it was-- and I still couldn't tell, but I could see movement. The dots were alive!

I took a sample home to stick under the microscope. It turned out that the great floating film consisted of millions of tiny black insects. I wasn't able to identify them. They are extremely hydrophobic (water repelling). You can't push them underwater without the water surface wanting to follow along. I didn't see any hopping on the water, but when removed from the water, they can hop. I think they are springtails. A water drop would hold them in place for viewing, but didn't give a good view. Once removed from the drop to dry space, they flee the strong light of the microscope and are very difficult to get a good look. So I'm not sure. Cool phenomenon, though, whatever they are.

[Herpchat]

Get PIcs!

[mewickham]

Here are some pictures:

The "oil slick" on the right is actually masses of millions of tiny, black, floating insects:


Here is a photo closer in:


Here is a shot under the microscope. Sorry that it's not good. I couldn't get the little devils to sit still: