Is most of the territory in SC TX (s of San Antonio)still privately owned ranch?
All of SoTex (except for a few NWRs and state parks) is privately owned.
Much new development to speak of?
As others have stated, the cities are expanding, but the rest is cattle/deer hunting country. This is good for indigos in that ranchers/hunting managers tend to leave stands of native brush and even add cattletanks. Water is one of the limiting factors in the distribution of indigos in SoTex, and I suspect there is more standing water in SoTex than before.
Another factor that is currently in the indigos favor is that SoTex contains many large ranches and few main roads. This decreases road mortality rates.
In the lower valley (the Brownsville/McAllen sprawl), the human population is expanding at an alarming rate. How quickly this will destroy habitat is unknown. Water management is becoming an issue and the farmland is expanding where irrigation will allow. Indigos don't seem to do well in irrigated farmland, even if there are corridor of native brush. I suspect it is a result of their large home ranges.
There are corridors of NWRs and state parks along the rivers where indigos are still common, but these parcels of land are becoming increasingly fragmented and isolated.
Fortunately, birding is big business in SoTex along the river. Birders are one of the largest groups of recreational outdoors people in the US (more people bird than play golf, for example). They also travel, spend money, and get involved in local politics. So there is at least a loud voice for conservation involved in planning along the lower Valley.
As an example, a plan to drain a roadside pond in the town of Zapata a few years ago was stopped largely by the influence of birders. A local golf course owner decided he wanted that water for his golf course and after several teenagers drowned in the pond when their car flipped into it, the golf course offered to "remove the hazard" by using the water. This golf course owner was apparently one of the politically powerful men in this small town and it looked like he would get his way. But this pond is one of the few places in the US that the White-collared Seedeater (a trash bird from Mexico) breeds, and birders were not about to let some golf course owner destroy the habitat. They contacted the city council and used receipts, hotel bills, etc, to show just how much money they spend in the town of Zapata, primarily to see those birds. The pond was saved. I have never seen an indigo next to this rather urban pond, but there is a big stand of brush and cane behind it, so maybe a cribo was saved as well?
So there are voices actively fighting the destruction of the lower valley. Next time you complain about birdwatchers, remember, you are on the same team!
Anyone know if the general public (especially the land owners) are very familiar with Drymarchon? Can they ID them? know they are harmless? Are thet the type of people that kill every snake they see?
Yes and no. Indigos benefit from the supposition that they eat rattlesnakes in the brush country. So the local ranchers tend to like them. When I worked in SoTex many years ago doing brush research, the ranchers we dealt with would actually stop their trucks and let the snakes finish crossing the farm roads as they viewed them as beneficial (I will say that parcels of land with healthy indigo pops rarely had atrox on them!).
In the lower valley, I suspect the urban residents just kill snakes in their yards, no questions asked. Here, the fact that indigos are such large snakes acts against them. A lot of people may tolerate a Coniophanes in their yard, but a 6 foot cribo is a different story.
Add to this the fact that many of the "residents" of the lower valley are actually "winter Texans" who live up north in the summer and come to the valley to live in their RVs for the winter. They aren't as tolerant of snakes as the local people, I suspect.
I'd like to delve into the state of this species in S. TX...but...damn if I can find anything on it.
This is a species in need of evaluation now, IMHO. The same can be said for the TX tortoise.
IMO, the short answer is, they are OK in about 2/3 of SoTex, and in real trouble in the other areas. The northern parts of the range are being wiped out by development and the sprawl of San Antonio. The populations in the lower valley are in a desperate fight for their lives. Across the border, errebennus is being wiped out by overgrazing, farming, and probably being killed and eaten as well. Hopefully the Tamaulipan thorn scrub can harbor a few populations, but whereever there is any water (even a stock tank), band land practices will probably really hit hard.
I imagine that the brushland and cattle lands of South central Texas are where this species will make its last stronghold.
But at least it isn't being wiped out by some idiots wearing mouse ears, like its sister species!
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Chris Harrison
...he was beginning to realize he was the creature of a god that appreciated the discomfort of his worshippers - W. Somerset Maugham
