Arquivos de periódicos de outubro 2017

01 de outubro de 2017

Global Warming and the Spread of Species

Photographed during evening showing a flight of grackles, starlings, and others to a communal roost. Here's an interesting observation from my mother. She was born and raised in Austin 92 years ago. She told me when she was a child, there were no grackles in Austin. She said there were in San Antonio and you would see them there when you visited like Franklin Roosevelt did when Mayor Maury Maverick and President Roosevelt opened the River Walk (a CCC New Deal program) in the 1930s.

Now when my wife and I moved to Johnson City from near Henly in 1980 (both of us originally Austinites), there were no grackles here. They did not arrive until the mid 1980s about the time invasive Argentine fire ants arrived. Now, of course, both species are part of the landscape. What's obviously missing now is the annual plagues of crickets we experienced around central Texas before the arrival of fire ants where most down towns and homes were invaded by hordes of crickets rubbing their legs and producing their incessant mating songs. Are the three events related? What do you think? Is it even true that grackles weren't living in and around Austin in the 1930s? What do your parents and grand parents remember?

Add to that this idea: non endemic species are spreading into your area wherever you live. Not only did grackles not inhabit Johnson City when we moved here, but neither did White-winged doves. As a kid, I remember seeing photographs of White-winged doves in Texas Parks and Wildlife magazine describing its range as being along the Rio Grande and I remember hunters paying exorbitant sums to be able to hunt this dove species.* How I wished then to have been able to see this unique Texas species. Today, these birds nest in our yard, wait for me to fill the sunflower bowl, and generally demand I give them edible things. They even overwinter here now and have to contend with Sharp-shined and Cooper's Hawks hunting them in town. That's during the day. At night they struggle to survive Barn and other owls that take over for hawks. Their lot isn't easy, so how is it they have moved out of the Rio Grande Valley into the Pedernales Valley and well beyond?

Are White-winged doves the only endemic species that has moved north in recent years? How about armadillos. In the late 19th century, they moved into Texas where we take them for granted. When I was a kid growing up in southern Mississippi, we didn't see Armadillos outside Texas. When we moved to Louisiana in my sixth grade of school, they had moved into southwestern Louisiana. I caught a few and kept them for pets for a while, discovered all the babies were the same sex and they couldn't see very well. I let them go because, well, they just don't make that great of a buddy. Plus, the buck like a bucking bronco! And if you're not careful, their bucking can hurt you. But the really interesting fact is that they are still moving north.

It's interesting to speculate that this advance of Armadillos can be linked to Global Climate Change. I believe that is the best explanation, and we know other species are following suit. No doubt there are other factors as well - obviously, there is a ecological niche for an ant eating critter, and there aren't many better than Armadillos.

Got any ideas yourself about why species are moving north out of Mexico and Central America not due to human transport? I'll add that Cattle Egrets arrived in the North America after 1952, probably as a result of tropical storms instead of global climate change, but then again, GCC may be responsible for larger storms that carry birds far from their original range and would be a good candidate for rafting populations around the world.


Posted on 01 de outubro de 2017, 09:04 PM by billarbon billarbon | 4 observações | 0 comentários | Deixar um comentário

09 de outubro de 2017

A Rattlesnake With an Incredible Story

This is a very large western diamondback rattlesnake that my wife and I encountered. His story and ours is one of the strangest I've ever heard described, even if you go back and read all of J. Frank Dobie's Texas classics where rattlesnake stories are told. And this story was not one of just surprise, wow, we were lucky to be alive kind of close call story, at least for us two humans. In fact, it was just the opposite and it was the snake who we could not believe was alive, so let me tell the story.

One night in early March in the early 2000s Elaine and I were returning home to Johnson City from a shopping trip to Austin. We were just a few miles inside Blanco County where the highway, US 290 twists and turns over several steep hills and valleys and one of those had a blind corner as you crested another steep hill. We were driving our Doge Caravan in the left hand lane with very little traffic on the road that late winter when our headlights illuminated what quickly came into focus as a very large diamondback rattlesnake coiled in the middle of our lane. At 60 mph there was no time to miss the big snake; the best we could do was straddle the critter which we did. But just before the big snake disappeared under the hood of the Caravan it was clear the snake was taking on the moving vehicle and he struck as he disappeared from our view.

From other experiences we've had with rattlesnakes and autos, - almost all in west Texas, we knew the outcome of this confrontation was not in the snake's favor. We made a quick decision to turn around, go back and take the snake off the road where his body could be consumed by other critters without becoming road kill themselves. When we arrived at the scene our fears were realized. I stopped the car off the road, illuminated the prostrate snake in the headlights, took a large stick I keep in the car for such purposes and picked the limp snake up, it's head dangling lifeless with blood oozing out of its mouth and dripping on the highway. I moved the snake off the road and dumped it in the drainage ditch confident that it would be a feast for raccoons and other varmints. With that we got in the van and went home to put up of groceries goods and get to bed.

That night a cold front came through and the morning was overcast and cool - really cool. By this time I had begun to think about the snake again and then decided to go back, and at least just cut the rattler off for a souvenir - probably one of the surest ways to get snake bitten. But that didn't happen to me but I still wanted that very large snake's very larger rattle. So I went back to the hilltop to perform my sad act. But the snake wasn't there. Well, so that's natural. My prognostication was right, the snake was probably some critter's meal and thinking so began walking the ditch back down the slope from which the snake had more than likely taken out of his canyon. In about thirty steps I found him again. Only now he was not dead or eaten, but coiled in rope fashion and lying quietly still. He did not move nor rattle at my approach and I'm sure the cooler weather was having an impact on his comfort. Most importantly, nothing had touched him in the night and the blood from his mouth was now dried and not weeping. So what I did next, anyone of you would have. I picked him up with my stick again, put him in a huge cardboard box and took him home to nurse him back to health. And that's what happened to him. Three weeks later he was actively looking for a way out of his 75 gallon trash can container, giving us every indication that he was ready to go home. He obliged us our support by never rattling or striking at us when we opened his locked trash can to see how he was doing. Finally, I took him back to the uninhabited (by humans) canyon, carried him well down the side of the hill off the highway and set him free. Then I took his picture. You can still see the dried blood on his nostril.

So how big was he or she? I didn't measure or weigh him, but he is one of the largest - if not the largest - diamondback I've ever seen. And I'd say I've seen five around his size, mostly in west Texas. I give him five to six feet of length, his girth, as you can see from the photo is nearly uniform and his head was almost as wide as my hand on which I've been bitten before, say three or more inches in width. While he is a large snake, I am a small person. His color, as you see here from my old 35mm Konica camera was a very dark ground color, nearly black as seems to be the norm in this part of Blanco County in way of comparison to other observations on this website. Anyway, he crawled away into his rocky terrain and I climbed way back to the highway and went home. We have never again seen a rattlesnake on this part of US 290 even though I've seen three in this area off road, it really does speak to the secretive lives of these - and most - snakes. Oh, if you want to read the story of my snake bite, look for Alan Tennant's article on snake bite in one of the issues of Texas Monthly in the late 1970s. A special note is that this snake never fed while captive. He did show interest in a store bought rat, but did not attempt to kill the rat, so the rat was removed and the snake liberated as we had no intention of keeping such a dangerous snake in our home.

Posted on 09 de outubro de 2017, 02:14 PM by billarbon billarbon | 1 observação | 8 comentários | Deixar um comentário