SAN FRANCISCO ESTUARY INVASIVE SPARTINA PROJECT 2612-A 8th Street ● Berkeley ● California 94710 ● (510) 548-2461 Preserving native wetlands PEGGY OLOFSON PROJECT DIRECTOR [email protected] Date: July 1, 2011 INGRID HOGLE MONITORING PROGRAM To: Jennifer Krebs, SFEP MANAGER [email protected] From: Peggy Olofson ERIK GRIJALVA FIELD OPERATIONS MANAGER Subject: Report of Work Completed Under Estuary 2100 Grant #X7-00T04701 [email protected] DREW KERR The State Coastal Conservancy received an Estuary 2100 Grant for $172,325 to use FIELD OPERATIONS ASSISTANT MANAGER for control of non-native invasive Spartina. Conservancy distributed the funds [email protected] through sub-grants to four Invasive Spartina Project (ISP) partners, including Cali- JEN MCBROOM fornia Wildlife Foundation, San Mateo Mosquito Abatement District, Friends of CLAPPER RAIL MONITOR‐ ING MANAGER Corte Madera Creek Watershed, and State Parks and Recreation. These four ISP part- [email protected] ners collectively treated approximately 90 net acres of invasive Spartina for two con- MARILYN LATTA secutive years, furthering the baywide eradication of invasive Spartina restoring and PROJECT MANAGER 510.286.4157 protecting many hundreds of acres of tidal marsh (Figure 1, Table 1). In addition to [email protected] treatment work, the grant funds also provided laboratory analysis of water samples Major Project Funders: collected from treatment sites where herbicide was applied, to confirm that water State Coastal Conser‐ quality was not degraded by the treatments. vancy American Recovery & ISP Partners and contractors conducted treatment work in accordance with Site Spe- Reinvestment Act cific Plans prepared by ISP (Grijalva et al. 2008; National Oceanic & www.spartina.org/project_documents/2008-2010_site_plans_doc_list.htm), and re- Atmospheric Admini‐ stration ported in the 2008-2009 Treatment Report (Grijalva & Kerr, 2011; U.S. Minerals Manage‐ www.spartina.org/project_documents/2008-2009_treatment_rept_list.htm). ment Service, Coastal Impact Assistance Water quality samples were collected and analyzed in accordance with the Aquatic Program Pesticide Application Plan and Addendum (Kerr 2009; U.S. Environmental Protection Agency, www.spartina.org/project_documents/2009_APAP_Updated_dec09.pdf, San Francisco Bay Water Quality Improvement www.spartina.org/project_documents/2009_APAP_Addendum.pdf). Fund The results of the water quality monitoring are presented in the Water Quality Report Association of Bay Area Governments for 2007-2010 (Kerr 2011; www.spartina.org/project_documents/2007- State Wildlife Conserva‐ 10_WQMonRept.htm). tion Board CALFED Bay Delta Inventory and efficacy monitoring were conducted in accordance with the Monitor- Program ing Program Quality Assurance Document (“QAD”; Hogle et al. 2008, updated 2009; U.S. Fish and Wildlife Service www.spartina.org/project_documents/QAD_2009_Update_All(032410).pdf). National Fish and The efficacy of treatment and the change in Spartina coverage over time was reported Wildlife Foundation in the 2008-2009 Monitoring Report (Hogle, 2011; Website: www.spartina.org/project_documents/2008-09_MonReport.htm). The text, tables, and www.spartina.org figures of the monitoring report are provided as Attachment 1 of this report. Pages 73-80 of the report provide excellent illustration of the successful restoration of pre- invasion marsh conditions following Spartina eradication. The San Francisco Estuary Invasive Spartina Project is a project of the State Coastal Conservancy, managed by Conservancy staff and independent contractors under their direction. Outcomes A nnual Inventory of Non-native Spartina in the Since its first full-scale con- San Francisco Bay trol season in 2005 (pilot 140 projects assessing various 120 treatment approaches on se- 100 lected sites were done in 80 60 2004), the ISP has reduced 40 the net area of non-native Spartina Inventory (HA) 20 Spartina by more than 90%, 0 Spring Fall Spring Fall Spring Fall Spring Fall Spring Fall Spring Fall Spring Fall and is believed to be on on- 2004 2004 2005 2005 2006 2006 2007 200 7 200 8 2008 2009 2009 2010 2010 Year track for successful eradica- tion within the next decade. Most remaining sites are at levels well below 1% of their historic peak infestation levels, and correspondingly, most of the remaining infestations cover less than 1% of the total site area. It is anticipated that by 2013 up to 90% of the 170 sites currently infested with non-native Spartina will have achieved the first year of ‘zero- detect’ of non-native Spartina; on track for 3 years of ‘zero-detect’ constituting eradication on those sites. The status of treated marshes following removal of the vegetative cover provided by non-native Spartina has been a large-scale return to a native-plant dominated condi- tion at suitable elevations and a return to the native mudflat condition at lower eleva- tions. An example of significant passive revegetation of treated areas can be seen at the Eden Landing marsh complex in Union City, where treatment on the central channel of Old Alameda Creek has been ongoing since 2005. Non-native Spartina has been nearly extirpated from the Creek, and as of 2011, the banks of the Creek that were formerly infested are dominated (in many cases with 100% cover) with native tidal marsh plant species like Sarcocornia spp, Jaumea carnosa, Frankenia salina, Distichlis spicata, and others. In contrast, at the Colma Creek complex in South San Francisco, the pre-invasion condition of the majority of the area was mudflat. Subse- quent to control work there, the area has transitioned back to mudflat-dominated habi- tat. The interruption and reversal of the ongoing expansion of the non-native Spartina in these marshes has, in many cases, significantly altered the vegetative structure from a dense, invaded condition to a more open native condition. As the marshes are allowed to recover from the Spartina invasion, it is anticipated that historical vegeta- tive complexity and density will be passively reestablished in most marshes. The change in vegetative structure following treatment has had anticipated effects on several animal species in infested marshes, especially the California Clapper Rail. At most locations where clapper rail were present within the non-native Spartina, local populations decreased during the first 4-6 years of treatment, sometimes notably, likely due to removal of protective cover provided by the cordgrass. At many of these locations, especially those where treatment efforts were begun earlier, clapper rail populations have shown signs of stabilizing or slowly increasing by 2010 and 2011 (citation) as native marsh vegetative structure has re-established. A few sites showed significant clapper rail declines, as had been predicted at the outset of the control pro- gram, as they had both a high density and cover of non-native Spartina hybrids and high rail populations. Prior to the establishment of the non-native Spartina, these ar- Estuary 2100 Grant #X7-00T04701 2 Final Report San Francisco Estuary Invasive Spartina Project July 1, 2011 eas previously had no, or little, tall vegetative cover, and the clapper rail populations had appeared or increased rapidly in response to the new, introduced habitat. Where an established native marsh was subsequently invaded by non-native Spartina, clap- per rail numbers show greater resilience to the removal of the vegetative structure provided by non-native Spartina. Although this has not been quantitatively studied, it is possibly due to underlying channel and hydrological complexity, native plant pres- ence (even at a low level beneath the non-native Spartina canopy) and consequent availability to recolonize the treated site and a developed food web that could re- bound after the removal of the non-native Spartina stressor . Since the vast majority of the non-native Spartina historically present in the Estuary has been removed as of the 2010 Treatment Season, and most remaining stands are disparate, stunted and represent fractional percentages of the marshlands where they are found, almost all impacts associated with the removal of the vegetative cover pro- vided by non-native Spartina have been realized. Treated marshes will continue on a trajectory of passive restoration of native marsh structure and composition. Over the medium to longer term, it is anticipated that rail populations will closely track pre- Spartina invasion levels as marshes revert to native conditions. Impacts associated with ISP activities going forward will predominantly be related to the potential to harass clapper rail as a result of monitoring, restoration or treatment activities, rather than habitat removal. Achievement of Objectives The Invasive Spartina Project initiated an aggressive Spartina treatment effort in 2005, and has successfully reduced the net area of invasive Spartina from greater than 800 acres, to less than 100 acres in six years. This is an exceptional accomplishment by any weed eradication standards, and it is made more significant by the number of environmental, physical, financial, and other challenges that have been overcome. The success has been at a cost of $1.5-2M per year, but it has helped to protect bil- lions of dollars of past, present, and future tidal marsh restoration projects, and pre- serve the priceless balance of the San Francisco Estuary ecosystem. The treatment work conducted by the four grantees under the Estuary 2100 Grant funding played a significant role in helping to achieve