Sunday, June 19, 2011
Looking for Bugs in the Rain: Buck Mt. Creek on Father's Day
Well, my daughter lives in Portland, Oregon, so obviously she wasn't going to call until 1:00 or 2:00 PM. So, I decided to go to Buck Mt. Creek to look for small minnow mayflies.
It was stupid. It was overcast -- dark sky -- but I thought it might clear. It didn't; it rained! But by then I had collected 20+ interesting nymphs -- so what to do? I decided to drive back home with my bowl and take the photos back there. Mistake. I made a sharp turn on the way back, the bowl overturned, and out came all of my insects! I quickly stopped at a store, bought a bottle of water, picked my bugs up from the floor of the car and made it back home with some things still intact! Ah joy.
But, I got some good photos, including this beautiful, fully mature, Perlesta common stonefly (Perlid). I still found some young nymphs, but I found two of these beauties in a single leaf pack. Another look.
Actually, this is just about the only stonefly I'm finding anywhere at the moment. The Perlodids seem to be gone -- except for some Isoperla holochloras in the high elevation tributaries to the Moormans River and up at the Rapidan.
I also saw -- but collected only a few -- a lot of flatheaded mayflies. Three genera: Epeorus (vitreus), Maccaffertium, and Leucrocuta. Somehow, one of the Leucrocuta nymphs I collected made it all the way home intact -- a small miracle.
The small size and large head, and the way it sped around the rock gave it away. But remember, the key thing is that gills 1-6 have fibrilliform between the gill and the body; gill 7 does not. I tried to get microscope photos of gills 6 and 7 this time to prove the point. Here they are:
My goal in going out today was to find some more small minnow mayflies since I want to establish the "hatch" pattern in this part of the state. Which genus/genera do we find in the winter? How about the summer and fall? So far, I've found Acentrella nymphs in this stream -- all of them very small -- but I've also found, recently, a three-tailed Baetis nymph. You may recall this recent photo.
I only found 1 nymph today -- again a three-tailed Baetis. He did not survive the trip to my home in very good shape: still, here is a photo.
Once we see the three tails, we have to look at the "labial palps": are they "rounded" or "truncate"? They're rounded.
And the last test -- does it have metathoracic wing pads? Yes it does: this one is very clear.
I hope by the end of the summer I can determine the "species" as well as the genus of this "three-tailer".
I imagine these will hatch in late August or September. But more on that later on.
Almost forgot. I also saw a fair number of Brushlegged mayflies today, and they're already pretty big.
They're very difficult to pick up with tweezers, but I did manage to grab this one.