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San Clemente Journal

Nature springs to life in open space preserved by TCA

Feb 05, 2005 01:42PM ● By Don Kindred

This spring, the Transportation Corridor Agencies (TCA) will once again sponsor its Spring Tours at several of its habitat preserves throughout South Orange County. TCA provides funding for the year-round protection and maintenance of more than 2,000 acres of prime habitat in Orange County. Once a year, during the springtime, wildlife biologists and botanists provide guided tours through the various TCA habitat preserves.
While most people in San Clemente are familiar with TCA because of its work developing the toll road system, TCA’s extensive environmental mitigation and habitat protection programs are not as widely known. However, TCA’s environmental programs have received numerous awards from private and public agencies alike. The Federal Highway Administration as well as the American Planning Association and the International Bridge Turnpike and Tunnel Association have all recognized TCA’s environmental programs with awards.
The specific nature preserves TCA will open to the public for Spring Tours this year have yet to be determined. Log on to the TCA website HYPERLINK "" to find out when and where the 2005 Spring Tours will occur. 
In recent years, TCA has provided tours of several spectacular nature preserves and biological research sites including the Upper Chiquita Canyon, Bonita Creek and Siphon Reservoir. In addition to preserving the natural flora and fauna, these preserves are used by scientists to study habitat revegetation, habitat conservation and management, and endangered species protection.
Upper Chiquita Canyon – This tour covers TCA’s largest habitat preserve. Upper Chiquita has been revegetated with native coastal sage scrub, oak woodland and riparian habitat. Much of Upper Chiquita was burned in the wildfires two years ago, but the restoration scientists have worked hard to revitalize the site with natural vegetation and wildlife.
Siphon Reservoir – This tour offers an opportunity to see the endangered California gnatcatcher. Specialized soil treatments were tested on a acre demonstration plot prior to implementation of the 214-acre Siphon Reservoir coastal sage scrub site. Today, 15 breeding pairs of California gnatcatchers, a federally listed species of bird, occupy the site. Biologists have developed a “cowbird-trapping” program that has contributed to the recovery of the gnatcatcher and the least Bell’s vireo, another endangered bird.
Bonita Creek – This tour is an annual favorite of bird watchers. Bonita Creek is a 21-acre wetland site that successfully serves as a link between the Upper Newport Bay and the San Joaquin Hills. On last year’s spring tour, coyote were sighted on the wetland. Mountain lion and a wide-variety of birds frequent the site. 
In addition to the habitat preserves, TCA also has constructed several wildlife undercrossings, which allow deer, mountain lions and other animals to pass freely and harmlessly underneath the toll roads. Scientists monitor these undercrossings and find them heavily utilized and highly effective. The proposed Foothill-South extension will also utilize undercrossings to provide habitat connectivity for the wildlife. 
TCA is working closely with several federal and state resource agencies to ensure that Foothill-South will be one of the most environmentally sensitive roads ever built. All the alternatives have been designed to avoid wetlands and they will employ extended detention basins to capture and treat the water run-off.

For more information about TCA’s 2005 Spring Tours, log on to our website "" You can also call us at 949-754-3478 or visit our San Clemente Information Center located at 209 Avenida Del Mar, Suite 201.