Monday, February 7, 2011
Stream Report: Buck Mt. Creek
(A large winter stonefly -- genus Strophopteryx -- crawls over a rock. There were about 30 large winter nymphs on this rock when I lifted it out of the water.)
At the moment, Buck Mt. Creek is "chock-a-block" full of Strophopteryx large winter stoneflies. It's also got a lot of black flies all of a sudden: you can look down at the rocks in the stream and see the black patches. They showed up real well on this white rock -- so I pulled it out of the stream for a close shot.
I saw no Taeniopteryx large winter stoneflies: I think they've all hatched (at least in this stream). And I only saw 1-2 small winter stoneflies -- and that was with 1-2 hours of looking intently. They too are pretty well gone for the season.
I did continue to find Clioperla Perlodid stoneflies -- and by now they're really big. The one in the picture below was about 1 inch long, not counting the tails. (Note that he's joined in this group photo by a Uenoid caddis, a Saddle case-maker caddis and a midge!)
While the large winters I found were crawling around on the bottoms and tops of the rocks, this Perlodid -- and about 4 others of similar size -- was rooting around in a leaf pack. No surprise there.
Perlodid stoneflies, Common stoneflies (Perlids), and Green stoneflies (Chloroperlids) are all "predators"
in their eating habits, all other stoneflies are herbivores/detritivores. So the Perlodids were looking for lunch -- in the form of large and small winter stones, crane fly larvae, midge larvae, and black fly larvae. I found a large number of black flies today in the leaves -- a fact that delighted, I'm sure, the Perlodids!
One more group shot. Here a large winter stonefly sits in the tray while a midge floats by doing the backstroke!