Restoration of Native Grasslands & Bird Populations
Sheep Grazing on the San Marcos Foothills
The San Marcos Foothills Preserve is a 200-acre open space of rolling grasslands, oak woodlands, and shaded creeks. These types of habitats are important to our local wildlife, but they are being taken over by invasive weeds and urban expansion throughout California. The foothills provide some of the largest grasslands in our area, but much of the preserve is covered in non-native grasslands which greatly reduce the quality of habitat that these grasslands can provide - thereby reducing the numbers of species that can live on the Preserve.
The Foothills lie at the base of the Santa Ynez Mountain range above Santa Barbara, just to the east of the 154 which winds its way up through the San Marcos Pass towards Lake Cachuma.
In the distant past, ground sloths, mastodons, wild horses, mammoths, and other pre-historic megafauna inhabited this region. Grasslands evoloved alongside these creatures and adapted to not only be able to withstand trampling, grazing, and soil disruption - but to thrive and outcompete other plants for space and nutrients.
In more recent history, elk and deer filled the role as common grazers in the Santa Barbara area, they were then replaced when ranchers brought livestock into the Santa Barbara foothills. While not a perfect replacement, these grazing animals effectively filled the same role as their distant pre-historic cousins.
When grazing animals were ultimately taken off the Preserve in 2008, the grassland composition began to shift. Many of our native grasses take the time to grow strong roots that enable them to regrow after their above-ground parts are grazed. Conversely, invasive annual grasses are adapted to grow quickly after the first rain of the season, produce and drop their seeds, and then die off. After any sort of large disturbance (like wildfires or mudslides), a thick mat of invasive grasses can grow quickly and completely inhibit the growth of any of our slower-growing native grasses.
Today, much of the 50 acres of grassland on the Preserve is dominated by invasive non-native grasses. Grazing levels the playing field a bit. Invasive annual grasses aren't able to withstand intensive grazing enough to produce seeds because they invest less resources into a strong root structure. Meanwhile, California native grasses can rebound after grazing because they have a strong root structure to support regrowth.
Livestock were taken off the Preserve in 2008, which was quickly followed by the Jesusita Fire of 2009 (map). Much of the Preserve's grasslands were left open, allowing for quick-growing invasive annual grasses to establish themselves, without interference from grazers, and exclude any native plants.
Much of the 50 acres of grassland has been taken over by invasive plants like ripgut brome (Bromus diandrus), black mustard (Brassica nigra), fennel (Foeniculum vulgare), and more.
Native wildflowers are an important part of the Preserve
As the quality of the grasslands has diminished, many grassland-reliant bird species have declined in presence to become uncommon visitors or not present on the Preserve at all.
Important Grassland Birds on the Preserve
Click each bird to learn more
Raptors on the Preserve
Habitat Restoration Goals
Restore populations of grassland-dependent birds on the Preserve by restoring 50 acres of grassland to native perennial grassland.
- Ecosystem: Create and sustain habitat for common and special-status species.
- Water: Increase the amount of water that is stored under ground and slowly released and decrease runoff.
- Climate: Increase ability of animals to survive effects of climate change. Increase carbon sequestration.
- Culture: Provide opportunities for gathering of native plants.
- Recreation: Provide public access.
- Participation: Provide educational opportunities and public participation in monitoring.
- Native grassland should have a minimum of 10 percent native grass cover and a maximum of 50 percent cover of native grass, a presence of several native forb species, and some bare ground ranging from 10 to 50 percent of the total amount in the grassland.
- Native grassland should have structural diversity including some tall grass and some short grass and forbs in order to provide shelter for grassland-dependent birds.
- Create and maintain a mosaic of grassland in which some areas have bare ground between native grasses, and other areas have some thatch between grasses with which ground nesting birds can build and hide nests.
- Recognize that it is impossible to remove non-native grasses from the grasslands. Nevertheless, time the livestock grazing so that the seed stocks of non-native grasses are depleted.
Channel Islands Restoration has been restoring habitat at the San Marcos Foothills Preserve since 2010. However, our methods have mostly focused on restoring riparian habitat and a few key areas of grassland.
Restoring 50 acres of grassland has been seen as a monumental task that we have neither the time nor the funding to work towards. However, if we are able to successfully manage grazers on the Preserve, we may be able to get them to do the work for us - naturally. As such, we are using sheep to graze the 50 acres at high intensity and short durations.
Why Grazing and Why Sheep?
In an effort to recreate the historic effects of grazing, we are bringing grazing back to these grasslands. Grazing is helpful for a number of reasons. Grazing is an excellent way of suppressing annual grasses while only temporarily impacting annual grasses. Our plan is to graze the grasslands as the non-native annual grasses start to sprout, but before they develop and drop their seeds. This way, hopefully after being cut, the grass seeds won't have enough resources to continue to grow and produce new seeds. Meanwhile, our native perennial grasses (like purple needlegrass) have a strong system of roots that helps keep them alive year round and also helps them rebound from grazing. In the best case scenario, this may even promote plant growth!
As for why sheep - sheep are relatively lightweight and do not eat the roots of the plants. In comparison, cows are heavy and compact the ground and contribute to soil erosion. Goats eat everything - roots and all (cows also may eat the roots of grass, but to a lesser extent).
Using 400 - 450 sheep we will graze an average of two acres per day. It will take 25 - 30 days to graze the entire 50 acres of grassland. This will happen twice per year, in late December/early January and in March.
The sheep will be enclosed in a two-acre electric fence and protected by guard dogs.
For questions or comments email us at email@example.com.
Thanks for reading!