Rancho Jamul Riparian Restoration:
By David Neubert, River Partners
In October 2007, the Harris wildfire began burning near the town of Potrero, just north of the U.S. and Mexico border in south San Diego County. The fire burned in a northwest direction, enveloping the California Department of Fish and Wildlife, Rancho Jamul Ecological Reserve and the Hollenbeck Wildlife Area. In total, the fire consumed over 90,000 acres and devastated the local community with loss of life and property.
In 2008, River Partners began to evaluate the Rancho Jamul/Hollenbeck site for its restoration potential. The wildfire destroyed habitat for numerous Neotropical migratory birds and listed species, including Least Bell’s Vireo, California gnatcatcher, Quino checkerspot butterfly, and the Arroyo toad. Additionally, the fire devastated habitat for eight other bird noted on California’s list of “Special Concern Species,” along with five bats, four reptile species and two mammals.
After the wildfire, invasive weed species such as arundo were some of the first plants to regenerate (see photo below). The California Department of Fish and Wildlife (DFW) was concerned that habitat at the Ecological Reserve and Wildlife Area would be permanently altered in ways that would make it difficult for listed and non-listed species to reestablish themselves after the fire. In early 2009, River Partners prepared a habitat restoration proposal for 178 acres of riparian habitat on DFW property along Dulzura Creek and Jamul Creek. These riparian areas contain some of the most biologically valuable habitat in the county.
(Above) Arundo sprouts emerge after the Harris Fire
San Diego is unique in that it has more threatened and endangered listed species than any other county in the U.S. Given the pressure that wildlife is under in high growth areas such as San Diego, it is imperative that wildlife managers and conservation officials keep existing habitat in a state that will support the many species that rely on this unique resource.
The Wildlife Conservation Board provided a grant to River Partners in the amount of $1.6 million to restore riparian habitat at the Rancho Jamul Ecological Reserve and Hollenbeck Wildlife Area in the spring of 2011. The award of the grant was in part delayed due to the 2008/2009 recession that resulted in many State agencies, icluding WCB, to slow or freeze spending on new projects.
River Partners began restoration planning at the Rancho Jamul/Hollenbeck sites in mid-2011. By this time some herbaceous species had already started to establish along the creek banks. Some of this new growth included native species, but much of it contained invasive species such as castor bean, salt-cedar and arundo. Areas away from the creeks remained largely devoid of native vegetation.
The area around the restoration site had once been used extensively by Native Americans and contained a number of historical sites that needed to be protected during the restoration process. To do this, River Partners hired a local archaeologist to provide guidance in restoration planning and implementation. The archaeologist worked with our field staff and was present whenever any grounddisturbing activities occurred (discing, trenching, drilling, etc.). As a result of the extensive archaeological sites at Rancho Jamul and Hollenbeck, River Partners modified our restoration plan footprint to avoid Native American campsites and the location of a settler’s adobe house.
With planning and permitting behind us, River Partners began planting the Rancho Jamul site in the fall of 2013. When completed, the site will contain over 19,000 native plants maintained on drip irrigation through the end of 2016. Additionally, we will control invasive species on the 178-acre site to ensure that the native species are well established and able to out-compete the invasive species. The outcome of all of this work will provide habitat for numerous threatened and endangered species, as well as Species of Special Concern and Neotropical migratory birds. The citizens of our state will be the ultimate beneficiaries through this project’s efforts to maintain biodiversity in one of the most complex ecological regions in our nation.
The above article originally appeared in the December 2013 issue of the River Partners Journal.