Natural History Notes



Friday, August 31, 2007

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.



Wednesday, August 29, 2007

red moon

So I planned to head out I-35 to the picnic area with the longhorn-silhouette shelters, south of the Justin road, about 4:30 am to see if I could compose some interesting photos of the lunar eclipse Tuesday morning. However, I stayed up late, and then I couldn't get to sleep and couldn't get to sleep, so then of course around 3am I fell sound asleep. I'd have missed it all, except Amy took a chance that I wouldn't be mad if she called me at ten after five!

I didn't go so far, turned off on the Ponder road and wound around on a couple of back roads to a dark farm driveway. There were a lot of vehicles that passed even on those dark roads; lots of Denton County country inhabitants having jobs in the Metroplex to which they commute at 6am.

Turned out the camera batteries were failing, so I would shoot a few quickly and then turn it off. Then I'd have to get it all set again next time - adjust ISO, set manual focus, zoom out, etc. Astronomical photography is not really the best use of a digital camera that's not much more than a point-and-shoot. I couldn't even see the dark moon in the viewfinder among the various bright symbols, till I had set the ISO up to a very noisy 400.

Still, I got a few half-decent images of the deep, dull orange totality. Then one side got very bright as it edged out of the shadow just before 6:30. Finally, about a quarter to seven, the partially illuminated moon was visible above the pre-dawn illuminated field. I think there are some sleepy cows under the trees. (Click on each image for a larger view.)

Half an hour later, after winding around exploring out around the municipal airport (if I'd had the camera ready earlier I could have caught an ascending small jet just above the dawn moon), I got back to the west side of town. The ghostly huge red sun rose in the haze, behind a low bank of clouds, appearing to come up through a slot, behind some clouds and in front of others.

Finally, going back nine days, here is the waxing moon trapped in the girders of the "MegaDrop" ride at the county fair.