Soaring temperatures and prolonged drought make it tough for South Texas wildlife to survive, but the hardy Texas tortoise is ideally adapted to the extremes of the region.
Dr. Frank Judd of Edinburg has studied tortoises for decades and is co-authoring a book on them that will be published in the coming spring.
Dr. Judd, a retired biology professor, said, "They are very tolerant of high temperatures. They can go without drinking whatsoever. They can get all of their moisture from their food if need be."
One of the primary sources of food and moisture for Texas tortoises is the prickly pear cactus, and they don't hesitate to munch the spiny pads.
"It's not that they are careful and picky about it. They get spines all in their heads and various places," said Dr. Judd.
While the thorny cactus pads provide sustenance, the tunas or ripe prickly pear fruits are a favorite summer treat.
Researchers are not sure just how long the adaptable tortoises can live, but Dr. Judd has a surprising estimate.
"Well over a hundred."
Habitat loss, exploitation by the pet trade and other factors have led to severe population declines throughout their South Texas range, and tortoises are a protected species making it unlawful to harm or possess them.
"The tortoises are in need of protection, but as long as there are large ranches in the area where we have owners that care about such things they have a chance," Judd said.