riffles and pools

This not-particularly-exciting-looking bit of stream landscape is a riffle — a shallow spot between deeper quiet pools — where the water splishes along over gravel shallows and miniature waterfalls, soaking up oxygen at every splash. This particular riffle is in Hickory Creek, just below the Jackson Road culverts, a couple of miles northwest of Denton. Kay and I collected benthic macroinvertebrates here this morning as part of the city's Watershed Protection Department effort to monitor health of streams. This one seems pretty healthy; we got a fair diversity of critters. It's been too long since I identified the catch in the lab. I've been forgetting what I knew a few months ago, and I don't really know what exactly we got.



As we left I snapped these glimpses of a medium-sized orange flutterby, who then fluttered off.

While we were hard at work, we were imperiously summoned by the car-horn of Jan, the property owner. She had seen Kay's pick-up parked by the roadside, and thought she had kids trespassing again. We explained ourselves, and she was happy to have us.

We then headed over to Pecan Creek under the Woodrow Lane bridge in east Denton, just across from the pound. In this downstream shot it looks verdant and non-urban, but that is deceptive. The next picture, of Kay getting set up, is more representational of the setting. Despite being downstream of most of the city, we got a lot of wriggly specimens — several leeches, lots of Odonata and Ephemeroptera. There were many, many tiny spinning things, maybe Daphnia, that we hope were trapped as we poured off the tray through our little sieve and tapped it into the collection bottle. Hope they didn't all escape right through the sieve.


Altogether we put in four service hours. I will try to go in next week for some sorting and ID.

In a related note, this afternoon Ellen helped me deal with weeks worth of clean laundry piled on the couch. When we got to the bottom of the pile, there on the couch was the Merritt and Cummins Aquatic Insects manual for which I have been searching! Duh.