Shallow Thoughts : : Jul

Akkana's Musings on Open Source Computing and Technology, Science, and Nature.

Tue, 05 Jul 2016

GIMP at Texas LinuxFest

I'll be at Texas LinuxFest in Austin, Texas this weekend. Friday, July 8 is the big day for open source imaging: first a morning Photo Walk led by Pat David, from 9-11, after which Pat, an active GIMP contributor and the driving force behind the PIXLS.US website and discussion forums, gives a talk on "Open Source Photography Tools". Then after lunch I'll give a GIMP tutorial. We may also have a Graphics Hackathon/Q&A session to discuss all the open-source graphics tools in the last slot of the day, but that part is still tentative. I'm hoping we can get some good discussion especially among the people who go on the photo walk.

Lots of interesting looking talks on Saturday, too. I've never been to Texas LinuxFest before: it's a short conference, just two days, but they're packing a lot into those two days and but it looks like it'll be a lot of fun.

Tags: , ,
[ 18:37 Jul 05, 2016    More conferences | permalink to this entry | ]

Sun, 03 Jul 2016

Midsummer Nature Notes from Traveling

A few unusual nature observations noticed over the last few weeks ...

First, on a trip to Washington DC a week ago (my first time there). For me, the big highlight of the trip was my first view of fireflies -- bright green ones, lighting once or twice then flying away, congregating over every park, lawn or patch of damp grass. What fun!

Predatory grackle

[grackle]

But the unusual observation was around mid-day, on the lawn near the Lincoln Memorial. A grackle caught my attention as it flashed by me -- a male common grackle, I think (at least, it was glossy black, relatively small and with only a moderately long tail).

It turned out it was chasing a sparrow, which was dodging and trying to evade, but unsuccessfully. The grackle made contact, and the sparrow faltered, started to flutter to the ground. But the sparrow recovered and took off in another direction, the grackle still hot on its tail. The grackle made contact again, and again the sparrow recovered and kept flying. But the third hit was harder than the other two, and the sparrow went down maybe fifteen or twenty feet away from me, with the grackle on top of it.

The grackle mantled over its prey like a hawk and looked like it was ready to begin eating. I still couldn't quite believe what I'd seen, so I stepped out toward the spot, figuring I'd scare the grackle away and I'd see if the sparrow was really dead. But the grackle had its eye on me, and before I'd taken three steps, it picked up the sparrow in its bill and flew off with it.

I never knew grackles were predatory, much less capable of killing other birds on the wing and flying off with them. But a web search on grackles killing birds got quite a few hits about grackles killing and eating house sparrows, so apparently it's not uncommon.

Daytime swarm of nighthawks

Then, on a road trip to visit friends in Colorado, we had to drive carefully past the eastern slope of San Antonio Mountain as a flock of birds wheeled and dove across the road. From a distance it looked like a flock of swallows, but as we got closer we realized they were far larger. They turned out to be nighthawks -- at least fifty of them, probably considerably more. I've heard of flocks of nighthawks swarming around the bugs attracted to parking lot streetlights. And I've seen a single nighthawk, or occasionally two, hawking in the evenings from my window at home. But I've never seen a flock of nighthawks during the day like this. An amazing sight as they swoop past, just feet from the car's windshield.

Flying ants

[Flying ant courtesy of Jen Macke]

Finally, the flying ants. The stuff of a bad science fiction movie! Well, maybe if the ants were 100 times larger. For now, just an interesting view of the natural world.

Just a few days ago, Jennifer Macke wrote a fascinating article in the PEEC Blog, "Ants Take Wing!" letting everyone know that this is the time of year for ants to grow wings and fly. (Jen also showed me some winged lawn ants in the PEEC ant colony when I was there the day before the article came out.) Both males and females grow wings; they mate in the air, and then the newly impregnated females fly off, find a location, shed their wings (leaving a wing scar you can see if you have a strong enough magnifying glass) and become the queen of a new ant colony.

And yesterday morning, as Dave and I looked out the window, we saw something swarming right below the garden. I grabbed a magnifying lens and rushed out to take a look at the ones emerging from the ground, and sure enough, they were ants. I saw only black ants. Our native harvester ants -- which I know to be common in our yard, since I've seen the telltale anthills surrounded by a large bare area where they clear out all vegetation -- have sexes of different colors (at least when they're flying): females are red, males are black. These flying ants were about the size of harvester ants but all the ants I saw were black. I retreated to the house and watched the flights with binoculars, hoping to see mating, but all the flyers I saw seemed intent on dispersing. Either these were not harvester ants, or the females come out at a different time from the males. Alas, we had an appointment and had to leave so I wasn't able to monitor them to check for red ants. But in a few days I'll be watching for ants that have lost their wings ... and if I find any, I'll try to identify queens.

Tags: , , ,
[ 09:28 Jul 03, 2016    More nature | permalink to this entry | ]