Sunday, September 9, 2007

Lizards!

I worried, shortly after we moved into the new house, that we had neither seen nor heard any lizards or geckos. I've always been fond of lizards, and I had looked forward to the chirping song of the warty little Mediterranean geckos that are so common throughout Central and South Texas.

For the longest time, they eluded us. Then, one day as we were walking out the front door, Tamara knelt and scooped a baby gecko off the floor before gently releasing it in the monkey grass out front.

Only a day later, I heard a rustling in some live oak understory, and looked up to see the little guy pictured here. It's a green anole (properly the "Carolina anole"), the small, native iguanid we called "chameleons" when we were kids, for their ability to change from green to brown and back again.

The geckos are well-established imports, another critter that has raced across the southern U.S. since its accidental introduction at ... Galveston? New Orleans? Miami? I don't know where the first gecko stepped off a ship or out of a shipping container, but I'm not unhapy they're here.

I think they complement, rather than compete directly with, the native anoles.

One of four species of "house geckos," Mediterraneans are another species -- like Great-tailed grackles -- that have a long association with human population centers. They're rarely found very far away from human habitation.

And, unlike green anoles, which are diurnal, Mediterranean geckos hunt primarily at night and in particular around outdoor lights. Where they're prevalent, it's not unusual to see half a dozen or more gathered on a vertical wall or window screen, waiting for moths and other bugs that flutter around the light.

Since the first sighting last week near the front door, we've spotted two more very young geckos on the back porch.

I'm still puzzled why, for nearly a month, we saw no lizards or geckos, and now we've seen four juveniles all in the space of a week. It could be that the snakes, mentioned in another post, have been gobbling the adults or that the chatter of jays that periodically hunt through the backyard have been picking them off.

It could be something else.

Whatever caused their absence, I'm happy to have some here now. Lizards and geckos, like frogs and newts, can be useful barometers of ecological conditions. A happy, healthy lizard population in the backyard might tell us that our backyard is doing okay.

Thursday, September 6, 2007

Poopy bird of paradise

In the last decade of the last century, I recall being excited about my first trip to Panama: Birds!, I thought. I'll see lots and lots of cool, exotic birds.

And it's true that there were noisy flocks of parakeets, usually moving too fast and too high to see clearly; an elegant trogan showed itself on a nature trail at Howard Air Force Base. And the pendulous, woven nests of orioles were abundant.

Some native Panamanians proudly pointed out the Brown pelicans in the canal, and bird books spoke glowingly of the prolific black vultures. But I grew up with both in Texas.

Mostly what I saw were grackles. Lots and lots of raucous, strutting, crapping grackles. Just like the ones we have at home.

In Panama, though, they somehow took on a more exotic, tropical cast. Male Great-tailed grackles are, without a doubt, handsome birds. With their flamboyantly long, keeled tail feathers, irridescent black plumage and piercing golden eyes, they look like something from far away.

I grew up with both the golden-eyed Great-tailed grackle and the dark-eyed Boat-tailed grackle on the middle Texas coast. The Boat-taileds prefer the marshy, coastal areas, and are common along the Gulf of Mexico and Atlantic seaboards. The Great-taileds frequented the ferry landing and beaches and the Whataburger and Dairy Queen parking lots.

Cliff Shackleford, TPWD's resident ornithologist, refers to the slightly smaller Boat-tailed grackles as "the good grackle."

"Boat-taileds are never the nuisance like the great-tailed ... they stick to natural habitat and aren't interested in eating discarded french fries in a fast food parking lot like great-taileds," he wrote to me in an e-mail. "One of the only times, however, that I've seen boat-taileds feed on pavement was shortly after Hurricane Rita in Sabine Pass when the local marshes were all flattened by the storm."

Recently I've seen small flocks of Great-tailed grackles -- usually mixed with another imimigrant, the European starling -- moving through the back yard on Abilene Trail, but none have yet come home to roost or nest.

Great-tailed grackles are fairly recent arrivals in Central Texas. Unlike starlings, famously introduced by a Shakespeare buff in Central Park, and unlike Austin's Monk parakeets (a breeding population was established by escapees), grackles appear to have gotten here on their own.

Their natural range expansion has been astonishing. In the 20th century, the species exploded out of its sub-tropical toehold in extreme South Texas and by 1920 was resident in Austin. In 1938 it was recorded in Waco, and by the 1950s it was established in the Dallas-Fort Worth metroplex.

By 2000, Great-tailed grackles had established breeding populations in Wyoming and Oregon. Oddly, the birds' movement has been mostly north and west; it still hasn't moved much farther east than Arkansas or Louisiana.

Many theories -- including global warming -- have been advanced as reasons for the species' amazing range expansion. The availability of food in both agricultural and urban settings no doubt contributes to the birds' success.

Historical accounts link grackles to Aztec communities in the 1500s; they still seem to find human population centers convenient for all sorts of things.

The birds are highly social, and typically roost and nest in large flocks. Trees in parking lots are particularly popular evening refuges, and a common sight in Austin is a cloud of the large, black birds descending noisily on a parking lot live oak. They just keep coming and coming, until one wonders how there can possibly be room for even one more bird.

Which brings me back around to the title of this post: savvy shoppers avoid parking late in the day beneath the trees that dot our appealingly landscaped shopping centers in Central Texas. To do so is to invite a certain trip to the car wash.

[Wiki Commons photo taken by Patrick Coin]