• Conserve target species throughout the planning area. Species that are well distributed across their native ranges are less susceptible to extinction than species confined to small portions of their ranges.
• Larger reserves are better. Large blocks of habitat containing large populations of the target species are superior to small blocks of habitat containing small populations.
• Link reserves with corridors. Interconnected blocks of habitat serve conservation purposes better than isolated blocks of habitat. Corridors or linkages function better when the habitat within them resembles habitat that is preferred by target species.
• Keep reserve areas close. Where reserves cannot be made contiguous through effective linkages or corridors, blocks of habitat conserved in close proximity to one another will be more likely to support target species than isolated areas.
• Reserves should be diverse. Blocks of habitat should contain a diverse representation of physical and environmental conditions.
• Protect reserves from encroachment. Blocks of habitat that are inaccessible to human disturbance better conserve target species than accessible habitat blocks.

Dudek helped three Southern California golf courses implement these principles to produce successful examples for sustainable biological resource preservation.

Trump National Golf Club
Trump National Golf Club, a 261 acre site that includes an 18-hole course, is situated on the southern portion of Los Angeles County’s Palos Verdes Peninsula.

The site’s developer sought to restore and enhance 125 acres of California coastal sage scrub in seven separate areas. These areas provide forage and cover for the coastal California gnatcatcher and other sensitive species. Preserved open space and mitigation areas create habitat linkages along the ocean bluffs and coastal canyons. Larger habitat blocks punctuate these corridors, providing substantial area for wildlife movement and space for sensitive plant species to flourish.

“Prior to this project, the site was highly disturbed, supporting degraded habitat and few native species,” explained Michael Sweesy, Dudek’s principal landscape architect and senior habitat restoration specialist who helped design the project. “While there were a variety of challenges such as maintaining public access during restoration, creating California gnatcatcher habitat, and controlling weeds, we ultimately restored a natural habitat that is also aesthetically pleasing.”

The site currently supports 19 pairs of coastal California gnatcatchers that utilize restored habitat areas on and adjacent to the golf course.

Arroyo Trabuco Golf Club
Arroyo Trabuco Golf Club, set along Trabuco Creek amidst the Southern Orange County Subregion Habitat Reserve, plays an important role in southern Orange County’s 130,000-acre Southern Subregion NCCP. The course lies at the southern end of the Arroyo Trabuco, a regional wildlife corridor and habitat linkage. Golf course mitigation included dedication of 360 acres of natural lands to the habitat reserve and habitat restoration.

The course’s habitat restoration efforts included restoring native grasslands, wetlands and coastal sage scrub, which are home to such listed species as least Bell’s vireo and California gnatcatcher. Arroyo Trabuco Creek, which runs through the middle of the golf course, supports about 10 nesting locations for the vireo as well as aquatic habitat for two sensitive fish – the arroyo chub and the partially armored threespine stickleback. The surrounding coastal sage scrub supports 10 gnatcatcher breeding pairs.

“These mitigation areas contribute to Arroyo Trabuco Golf Club’s aesthetics, biodiversity, wildlife movement through the preserve, and habitat continuity enhancement,” said Sweesy.

The Crossings at Carlsbad
Completely surrounded by the City of Carlsbad’s 25,000-acre Habitat Management Plan (HMP), The Crossings at Carlsbad links two core reserve areas.

“Blending the course into its surroundings was a key consideration in the habitat restoration process,” explained Sweesy. “We ultimately restored 48 acres of coastal sage scrub as well as created and enhanced nearly seven acres of wetlands.”

“As a result of this complex restoration effort, Carlsbad created and enhanced habitat that exceeds all permit requirements,” added Sweesy.

The course, scheduled to open in late summer 2007, surrounds each hole with habitat and/or native buffer areas. This maximized habitat mitigation opportunities, creating stronger cohesion between HMP lands and golf course facilities as well as greater habitat continuity and connectivity within the HMP/golf complex.

“In all three cases, golf course development and associated habitat restoration combined with regional reserve planning resulted in a net benefit to native species,” concluded Joshi. “The golf courses act as a ‘soft edge’ on the adjacent preserves and offer an opportunity for development while preserving biological functions as ‘live-in’ habitat, corridors, and buffers.”