Leapin Lizards! Big Bend National Park is a great place to discover the diversity of many creatures like birds, snakes, and lizards. Big Bend is home to an amazing array of lizards! Twenty-two species to be exact.
Why are lizards important? What is their role in this ecosystem? Most of the lizards here, are found in the diet of many other creatures. Lizards are the main prey item for roadrunners, one of Big Bend’s most popular birds. They help regulate the populations of other animals here, particularly insects, by feeding upon them.
Did you know that lizards in Big Bend are active most the year-round? Lizards are ectotherms, or cold-blooded creatures, because of this they need to regulate their body temperatures. Any extreme (too hot or too cold) could mean certain death for these animals. During the heat of the summer they are often hiding in burrows, while in the cold of the winter they are often burried below the ground surface (sometimes in burrows).
Visitors to Big Bend NP most frequently see the whiptails, earless, and spiny lizards. Often, lizards will be heard and not seen as they scurry through the vegetation off the side of a trail, though ones that are sighted are often fast and hide easily. The largest lizards in the park are the Collared (Crotaphytus) and Leopard (Gambelia) lizards which can measure over a foot! Both make their living off eating other lizards, insects, spiders, and small snakes.
There are other big lizards here though they are small compared to the monitors or komodo dragons. The largest Texas horned lizard (Phrynosoma cornutum) ever recorded was found here in Big Bend NP. Texas horned lizards are not very abundant in Big Bend NP, in the few places where they are located they are not in very big numbers. However, there is no evidence yet, that would suggest that this is abnormal. It is more likely that Big Bend NP may not have the proper type of habitat necessary for these lizards. The main and often only, food item for the Texas horned lizard is the harvester ant (Pogonomyrmex) which feeds mostly on grass seed. It is possible, if at one time there were larger grasslands in Big Bend, there may have been a larger harvester ant population and thus a greater number of Texas horned lizards.
