A portion of San Geronimo Creek purchased for protection and restoration by SPAWN. photo by SPAWNusa.org

By Todd Steiner, Salmon Protection And Watershed Network

Turtle Island Restoration Network recently acquired a four-acre property on the most important un-dammed headwater tributary of Lagunitas Creek, which hosts the largest spawning population of critically endangered Central California Coast coho salmon.

The purchase will allow the Marin County organization to promote the long-term survival of coho salmon and their nests, known as redds, and to improve water quality for the safety of residents.

“With one of the highest densities of redds found anywhere in the 101-square-mile watershed, this property has high ecological value for salmonids,” said Director of Watershed Conservation Preston Brown. “The permanent protection of this property will help give coho salmon a fighting chance at survival in the watershed and help maintain the rural character of the San Geronimo Valley.”

Measuring nearly .3 miles, the property in Forest Knolls includes both sides of two coho-bearing streams: nearly 1,000 feet of San Geronimo Creek, approximately 100 feet of coho-bearing Arroyo Creek, and the confluence of these two streams. Prior to being purchased for conservation, critical salmon habitat was destroyed by illegal structures and part of the riparian zone was being used to store vehicles, heavy equipment, gasoline, and other toxics right on the creek bank.

“This property has one of the largest stretches of creekfront habitat of any residential property in the San Geronimo Valley,” said Preston Brown. “There are many opportunities for clean-up, reclamation, enhancement, and restoration necessary for the continued survival of coho salmon.”

In addition to removing and restoring the polluting storage area, the acquisition provides for permanently protecting intact riparian habitat and restoring destroyed habitat by removing unpermitted structures such as garages, buildings, concrete pavers, retaining walls, and fences and replacing with riparian habitat. The restoration will also include removing the flash-board seasonal dam buttresses, an old well and pump house; cleaning up and removing car parts and other metal debris in coho spawning reaches; stabilizing banks; creating floodplain and placing large woody debris in the creek; and retiring all riparian and other water rights.

“We will take down unpermitted structures, remove invasive plants, and restore the damaged creekside riparian habitat by planting redwood trees to sequester carbon and fight climate change,” said Native Plant Nursery Manager Audrey Fusco.

Since the listing of Central California Coast coho salmon under the Endangered Species Act in 1996, their population has continued to dramatically decline, and the fish are now considered close to extinction. Marin County’s population of coho salmon is one of the strongest remaining in California and critical to the recovery of the species throughout Central California, but it remains severely threatened from past and current development.

SPAWN continues to pursue litigation against Marin County to ensure strong regulations and adequate enforcement of creekside coho habitat.

The house on the newly purchased property is being used to expand SPAWN’s residential internship program for recent college graduates, and as affordable housing for staff.

To learn more about SPAWN’s residential internship program, visit seaturtles.org/about-us/internships/

For more information: seaturtles.org/our-work/our-programs/salmon/