Thursday, March 14, 2013

Tough Conditions: After the Snow and the Rain

A foot of wet, heavy snow followed by 1-2 inches of rain -- our streams and rivers are high, fast, and muddy.  At the moment, there's only one place nearby to find any insects -- Sugar Hollow's small mountain streams.  Even there, as I found out this morning, it's difficult going: they too are high and fast and a little off color.  Still, there were plenty of insects in the leaf packs and on the bottoms of rocks.

Above -- the flatheaded mayfly Epeorus pleuralis.  I didn't see as many this morning as I have in recent trips to this stream.  It's got to be the swift water: even these "clingers" have trouble holding on at the moment.  Still, I did get some nice photos of this one.

2. Green stoneflies -- Chloroperlids -- genus Sweltsa.  I saw quite a few.

Not yet fully mature, but getting close now: note the rounded, dark wing pads.  I was hoping to get some really sharp photos of this particular nymph, but this is one of those miserable insects that never stops swimming around in the tray!   They never pause.  We have about one month to go before they'll start hatching.  This is one of the many adults I saw on the rocks in the Doyles River last April.

3.  A "Rolled-winged" stonefly (Leuctridae), genus Leuctra.

They're getting bigger: we can finally make out the tips of both sets of wing pads.

But these don't mature until late in the spring.  Only then are the wing pads easy to see.  This is a beauty that I found in Sugar Hollow on 5/30 last year.

3.  Prong-gilled mayfly, genus Paraleptophlebia.  Lots of them in the leaf packs.

4. Uenoid caddisfly larva, Neophylax mitchelli.  The sharp tubercle on the head is easy to see in some of these photos.  Note that the ballast stone on one side of the case has been sheared off.

The Uenoids have started to pupate: I saw clusters of cases on a number of rocks.  These larvae  huddle together in groups as they seal up for pupation.

5. And, a "hanger-on" from the winter: large winter stonefly, Taenionema atlanticum.  Still some around, but most have already hatched.


Another nice day tomorrow, before the clouds move in once again.  So I'll be off to another small stream in the morning, one even small than the one that I went to today.

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