The Mount Hamilton Upper Pajaro River Floodplain Conservation and Restoration Project encompasses 1.5 million acres of rangeland, riparian areas, and forests. The project identifies core conservation areas, including dispersal corridors and intact ecological systems in order to protect and enhance biodiversity and reduce habitat fragmentation. By identifying multiple management objectives, TNC CA was able to build strong, lasting partnerships to support this extensive conservation and restoration project.
The Mt. Hamilton, Santa Cruz, and Gabilan Mountain ranges meet at the Pajaro River, an area rich in wildlife, water, agriculture and ranching. Birds use the coastal and floodplain wetlands as major resting points along the Pacific flyway. Wild animals such as mountain lions and badgers migrate and disperse through the landscape. The watershed contains some of California’s most productive farmlands and many of the remaining large ranches in and around Silicon Valley.
The region contains some of the last streams supporting steelhead trout along the Central Coast. These streams flow into the Pajaro River, which in turn drains into the Monterey Bay, a National Marine Sanctuary. As our climate changes and habitats shift, keeping these lands intact and connected will be critical for allowing plants and animals to persist and adapt. As Robin Cox, a senior ecologist with TNC explains, “minimizing fragmentation is crucial to the long-term viability of California’s ecosystems” and preserving large expanses of open space keeps the gene pool healthy for all species.
Mount Hamilton’s mosaic of extensive oak woodlands and annual grasslands is interspersed with seasonal wetlands and dozens of life-sustaining creeks and streams. Natural habitats host endemic plant and wildlife species, including the endangered Bay checkerspot butterfly and the San Joaquin kit fox. Larger animals, such as mountain lion and elk, roam the area and a variety of birds, including golden eagles, rely on Mount Hamilton for food and shelter. Agricultural crops and cattle, raised on farms and ranches that have been in California families for generations, thrive on Mount Hamilton’s rich soil and moderate climate. The area spans six counties with diverse demographics and politics. East of San Jose and the San Francisco Bay, between Highway 101 and Interstate 5, in the southern Diablo Range, the Mount Hamilton project protects some of the last significant, unprotected open space between the San Francisco Bay Area and California’s great Central Valley.
While focused on the entire landscape, TNC – CA’s immediate goal is to protect – through conservation easements and habitat restoration projects – several properties in that landscape to conserve the ecological values and function of the upper floodplain and wildlife corridors. The protection of the upper floodplain also ensures critical flood protection for the lower floodplain, more specifically for the towns of Pajaro, Watsonville and the surrounding strawberry and lettuce farms. Key conservation targets include:
A climate change impact vulnerability assessment was conducted and used to guide adaptation actions, including targeted land protection and efforts to restore significant riparian habitat. In addition to climate change, major threats to these systems include:
Regional planning efforts aim to address these challenges in order to move the region towards more ecologically sustainable land and water use patterns.
From the outset, TNC conservation strategies in this landscape have been governed by sound science and proven conservation planning principals. However, these strategies are based on the climatic conditions and species distributions that have been observed in the recent past. Climatic conditions have already begun to change, and are projected to get much hotter and possibly drier over the next 50 years. TNC recognizes the need to modify and update our existing strategies to better steward the plants and animals of the Mount Hamilton Project through an uncertain and changing future. Additional materials on Mount Hamilton climate adaptation planning efforts are available here.
To inform management decisions in the region, TNC-CA and partners conducted comprehensive climate change planning and vulnerability assessments for this area. The climate change planning effort began by identifying six key species and habitats in the Mount Hamilton project area, which includes the upper Pajaro River floodplain, that are likely to be vulnerable to climate change. TNC then used a step-by-step approach to develop adaptation strategies following a method similar to the one described in Redesigning biodiversity conservation projects for climate change: examples from the field. This approach involved developing climate change informed “hypotheses of change” for each species/habitat, and then
bringing a team of experts together in a workshop setting to develop adaptation strategies to minimize the negative impacts of climate change. TNC relied on climate change data and modeled species range shifts developed by TNC. The entire process took about one year. Full details about the species, methods, and workshop participants, and the prioritization process are available here.
As a result of the climate change planning, TNC developed a large list of potential actions to help the six focal species/habitats adapt to climate change. This effort looked for areas where multiple focal species were found, and identified the Pajaro as one important area because it contains a steelhead stream, supports important amphibian habitat for species like the California Tiger Salamander, and has the potential to add connectivity for wide-ranging mammals like the Badger. TNC also chose this site because it helps humans adapt to climate change by storing floodwaters and helping to protect the downstream agricultural lands and the towns of Watsonville and Pajaro.
The key actions were selected to implement in the Pajaro include land protection and restoration of riparian habitat. TNC chose these actions because much of the potential corridor is not protected, and land protection is designed to last in perpetuity. These actions are well suited to TNC’s capacity, and they also align with existing priority actions from previous planning efforts.
Through the years, TNC has documented planning and anticipated actions in initial assessments, restoration plans and grant proposals. To date, several properties have been protected by TNC and partners; restoration has been completed on at least two properties and two additional are in the planning/fundraising phase. In addition, baseline wildlife monitoring has been completed.
Key project strategies focus on:
Engaging in land use planning and policy issues, including
Building partnerships to
Continuing conservation science, land management, and planning.
The long-term conservation vision for the Mt. Hamilton region aims to::
The project is currently in the implementation phase. TNC CA finds that having a long-term commitment to goals, and ongoing communication with partners and landowners/community members are key elements that are working well.
Local resource conservation groups and have been convening meetings and helping TNC build partnerships in the region. Efforts are underway to build coalitions to continue these efforts. TNC’s stakeholder engagement efforts include regular meetings with a group of governmental and non-profit organizations and resource agencies focused on conservation project planning and coordination in the upper watershed. With that group, TNC is preparing to launch a “greenprinting” process to focus conservation priorities, define roles, and bring additional resources to conservation efforts. The group will work together to compile existing studies and data on conservation goals, explore additional data sets and scenarios, and build a tool that all participating agencies and organizations can use to focus their efforts. This process will include outreach to a wider set of community stakeholders, including the agricultural community, politicians, land use planners, and others. It will complement TNC CA’s on-the-ground restoration efforts, which, for some projects will be implemented in partnership with local schools.
The Mount Hamilton project is highly collaborative with continuing support from:
Other NGO partners include:
While traditional strategies of acquisitions and easements have been used effectively on Mount Hamilton, the project calls for increased emphasis on collaborative planning and partnerships. In Santa Clara County, for example, the Conservancy has a seat on the local public stakeholder committee that is reviewing the costs and environmental impacts of a proposed new reservoir. In addition to addressing the proposed high-speed rail line between Los Angeles and San Francisco that could bisect and fragment the area, Conservancy staff members are working with government and nonprofit agencies to maximize the existing transportation corridors in the area. Likewise, Conservancy staff are working with elected officials to explore a conservation-friendly freeway route to alleviate traffic congestions.
Global Conservation Organization
More than 119 million acres of land and thousands of miles of rivers protected worldwide, and more than 100 marine conservation projects globally.
3,500 employees worldwide
Over 1,000,000 members internationally
165 acres, currently owned in fee
• Rangeland (10% being removed from rangeland for riparian restoration corridor)
• Floodplain (9,000 acre floodplain identified - this corridor is critical to reconnect mountain ranges on either sides of the property)
• Woodland birds
• Potential California Tiger Salamander habitat (surveys in progress)
Not open to the public, but educational component bringing environmental education into elementary schools. For example, the Gonzales farm is a working landscape where the Point Blue Conservation Science’s Students and Teachers Restoring a Watershed Program (STRAW) are working to improve degraded habitat and restore a corridor for migrating animals along the Upper Pajaro River. Learn more about education efforts on the Gonzolaz Farm in the Mt. Hamilton conservation area.