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