A healthy parkDoctors use thermometers, X-rays, and MRIs to check on the health of their patients. At Palo Alto, researchers rely on tortoises to monitor the natural health of the park.
Every six months since 2008, the park's natural resource specialist, Gulf Coast Network (GULN) staff, and other partners and volunteers have combed the brush and prairies of Palo Alto. Their goal is to locate, mark, and track Texas tortoises (Gopherus berlandieri) living in the park.
This species is very sensitive to environmental changes, making it a good barometer of the ecological well-being of the park. For example, evidence of increased tortoise mortality can indicate a deterioration of habitat areas long before other more hardy species are affected. By contrast, a thriving or growing tortoise population—especially the presence of young individuals—suggests site conditions remain relatively stable. By tracking the health and numbers of tortoises within the park boundary, Palo Alto hopes to keep tabs on the "vital signs" of the battlefield and surrounding lands.
The project is part of a service-wide initiative to keep a close eye on all parks with a significant natural component. The goal of this inventory and monitoring program is to help identify significant environmental issues in National Parks and address them before they reach a catastrophic stage.
Parks like Palo Alto have documented all plants and animals within their boundaries and selected indicator species to be watched. Palo Alto monitors a variety of plant, bird, amphibian and reptile species, but the Texas Tortoise stands out as the most important indicator of park health.
To date, the tortoise program has provided positive feedback about the park's condition. Monitoring crews have located, marked and tracked more than 160 individual tortoises and have found a viable and healthy population on park grounds. But there is also cause for concern. Some tortoises have been killed by other animals, including feral pigs, that have taken up residence on the battlefield. Others perish while trying to cross the busy roads that form the boundaries of the park. It is also notable that the tortoises seem to prefer the dense chaparral, a habitat area that is declining quickly in the developing lands surrounding the battlefield.
Past, present & future
The park will continue to keep a close watch on the tortoises and their condition in the years to come. The species, originally identified by naturalist Jean Luis Berlandier—a participant in the battle of Palo Alto—has long been part of the history of the site. Through careful monitoring and care, Palo Alto Battlefield hopes that they will remain part of the future.
For more information about resource projects at the park, contact our Resource Manager.
Did You Know?
Palo Alto Battlefield has become home to a small herd of Nilgai—a type of antelope native to India and Pakistan. Originally brought to Texas ranches for exotic hunts, the animals have migrated into the Rio Grande Valley.