Bridging Worlds: Wildlife Crossings in San Antonio

How Innovative Infrastructure is Saving Wildlife and Connecting Habitats

Wildlife Crossings in San Antonio

As dusk settles over Phil Hardberger Park in San Antonio, a slim deer, with ghostly white eyes, is captured in a nighttime photo, calmly munching on a branch. This serene image, alongside that of a curious coyote inspecting a camera, represents more than just snapshots of local wildlife. These are historic moments—the first official recordings of animals using the largest wildlife crossing in the United States: the Robert L. B. Tobin Land Bridge.

Spanning 150 feet in both length and width, this bridge gracefully arches over the bustling Wurzbach Parkway, connecting the two sides of Phil Hardberger Park. This engineering marvel, completed in April 2021, provides safe passage for the park’s numerous animal inhabitants and its human visitors, integrating nature and urban life harmoniously.

San Antonio Parks and Recreation naturalist Casey Cowan highlights the park’s features that make it a haven for both wildlife and people. Water features, small ponds rimmed by stones, attract various animals, including birds and white-tailed deer. Artistic wildlife blinds designed by local artists allow visitors to observe the park’s residents discreetly. Motion-triggered cameras positioned along the trails capture the activities of the park’s inhabitants, including deer mischievously standing on their hind legs to nibble on newly planted sumac trees.

Despite its function as a wildlife crossing, the Tobin Land Bridge seamlessly blends into the park’s landscape. Many visitors are unaware they are walking over a highway until they reach the fencing and look down. The bridge’s naturalistic design serves as a testament to how human ingenuity can integrate with nature.

Meanwhile, in South Texas’s Rio Grande Valley, a different type of wildlife crossing has garnered media attention. On January 25, 2021, an automated camera captured images of OM331, a five-year-old ocelot, using an underpass beneath Farm-to-Market Road 106 near the Laguna Atascosa National Wildlife Refuge. This small, unassuming concrete culvert plays a crucial role in the survival of the ocelot, a species with only fifty to eighty individuals remaining in South Texas.

Hilary Swarts, a wildlife biologist at the refuge, notes that these underpasses, completed in 2019, have significantly reduced vehicle-related ocelot deaths. These simple structures, accompanied by chain-link fencing to guide animals towards the passages, are a cost-effective solution to a deadly problem. Other species, including bobcats, javelinas, and alligators, have also benefited from these crossings.

The Tobin Land Bridge and the South Texas underpasses are part of a broader trend in wildlife conservation. The concept of wildlife crossings originated in Europe in the 1950s and has since spread worldwide. These structures address the devastating impact of highways on wildlife, reducing animal-vehicle collisions and reconnecting fragmented habitats.

In the United States, wildlife crossings are becoming increasingly popular. For instance, Colorado’s Highway 9 saw a 90% reduction in animal carcasses after the construction of wildlife underpasses and overpasses. Banff National Park in Canada, known for its early adoption of wildlife crossings, reported an 80% reduction in wildlife-vehicle collisions.

While large mammals often receive the most attention, smaller animals also benefit from these crossings. In New Zealand, blue penguins use what looks like a large drainpipe, and on Christmas Island, red crabs traverse a specially designed bridge. These varied and innovative designs showcase the adaptability and importance of wildlife crossings.

Texas has been quietly leading the charge in wildlife crossings for two decades. Since 2016, the Texas Department of Transportation (TxDOT) has accelerated its efforts, incorporating 33 wildlife crossings with another 23 in planning. These crossings protect not only ocelots but also coyotes, deer, rabbits, and a range of other species.

The success of the Tobin Land Bridge, funded by a combination of public bonds and private philanthropy, demonstrates the impact of community support and visionary leadership. Former San Antonio mayor Phil Hardberger, who spearheaded the project, reflects on its significance: “So many people have told me, ‘I feel better just being there.’ The park and bridge may be the most important things I did as mayor.”

Park naturalists are documenting unique species crossing the land bridge at Phil Hardberger Park

The benefits of wildlife crossings extend beyond immediate safety. They promote genetic diversity and help restore fragmented ecosystems. Casey Cowan notes that the crossings in Phil Hardberger Park help rebalance the ecosystem by allowing animals to move freely. In the Rio Grande Valley, the underpasses have provided much-needed assistance to the ocelot population.

Encouragingly, recent legislative developments promise further support for wildlife crossings. The INVEST in America Act and the Surface Transportation Reauthorization Act, currently under consideration in Congress, propose significant funding for building and researching wildlife crossings. If passed, these bills could usher in a new era of connectivity and conservation.

In a world where highways and urban development often disrupt natural habitats, wildlife crossings offer a glimpse of hope. They remind us that, with ingenuity and dedication, we can create spaces where both humans and wildlife thrive together.

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