Despite differences in appearance and reproduction, amphibians and reptiles are generally grouped together into one category known as herpetofauna, or simply ‘herps’. Herps play a crucial role in the Preserve ecosystem through the control of rodent and insect populations as well as by serving as prey for numerous species, such as the greater roadrunner and the striped skunk. Herps can be found in a wide variety of habitats across the Bull Creek Nature Preserve. For instance, the Texas spiny lizard is an arboreal (or tree-dwelling) species known for its skillful climbing. The cliff chirping frog is a terrestrial (or ground-dwelling) species that lives in the crevices and caves of the limestone hills. The red-eared slider is an aquatic (or water-dwelling) turtle that feeds on aquatic plants and can be seen in Bull Creek basking in the sun on logs.
Amphibian species such as salamanders and frogs have smooth skin that is permeable to water, making them more vulnerable to toxins than most species. For this reason, amphibians can serve as an indicator species, or a ‘canary in the coal mine’. Historically, miners would take a canary down into coal mines because canaries were more sensitive to toxic and explosive gases. If the canary stopped singing, the miners knew that the gases had reached a dangerous level and they had to leave immediately. Similarly, if amphibian populations start to decline in the Preserve, it can indicate that watershed conditions and the overall health of the ecosystem may be declining due to pollution.
One important indicator species in the Preserve is the Jollyville Plateau salamander. The salamander lives under rocks and rubble in waters around springs and seeps. Studies have found significantly lower populations of the salamander in areas of increased development and degraded water quality. This means that the salamander could function as an early warning for water quality problems of potential concern to human health. The Jollyville Plateau salamander is currently not listed as endangered.
Reptiles found on the Preserve include lizards, turtles, and snakes. Only a small percentage of the snakes on the Preserve are actually poisonous—including the broad-banded copperhead, the Western diamondback rattlesnake, and the Texas coral snake. However, it is important to always use caution around snakes while hiking. If you see a snake on the Preserve, it is safest to slowly backup or walk away and allow the snake to pass. For more information on identifying poisonous snakes, visit the Texas Parks and Wildlife Venomous Snake Safety website.