Source: sonoma.edu/preserves/prairie Photo Credit: D. Immel -Jeffery 2010

1. California Grasslands: Biodiverse Landscapes in a Biodiverse Region Source: sonoma.edu/preserves/prairie Photo Credit: D. Immel-Jeffery 2010

2. GLOBAL HOTSPOTS OF BIODIVERSITY Mittermeier et al. 1999

3. North Coast/Klamath • 14 million acres • 40% of California’s total runoff (10 major coastal rivers) • Rugged forested mountains (3,000-8,000 ft)

4. The Global Domination of Grasses • Grasses evolved in the late Jurassic (part of the “abominable mystery”) • Grasses co-evolved with and are incredibly resistant to disturbance • Grasslands cover 33-41% of the earth’s terrestrial surface Source: sonoma.edu/preserves/prairie Photo Credit: D. Immel-Jeffery 2010

5. Definitions • Grasses: members of the family Poaceae; not forbs, shrubs, vines, rushes or sedges • Grasslands are composed primarily of annual and perennial grasses and forbs (from the Greek Phorbe, or fodder) • Savannah: grassland with widely spaced trees • Prairie: grassland in a moderately dry temperate region; from the French prata, meadow (Lincoln, et al. 1998). First used by French trappers on the North American Great Plains. Source: sonoma.edu/preserves/prairie Photo Credit: D. Immel-Jeffery 2010

6. Prairies and Carbon Sequestration • Prairies remove more carbon from the atmosphere than any other ecosystem in the United States • Root die-back (from grazing, mowing) deposits carbon in the soil • Annual cycles of deposition and re-growth create an incredibly effective carbon pump Photo Credit: Mark Stromberg Illustration courtesy of the Hastings Natural History Reserve

7. California’s Coastal Prairies • Unlike other North American grasslands, coastal prairies grow in California’s “fog belt”, which shapes species composition • May have been dominated by wildflowers instead of grasses (Minnich 2008; Holstein 2011) • Early explorers, and early naturalists such as John Muir, documented wildflower-rich prairies (see Lulow & Young 2011). Source: Wikimedia Commons Photo Credit: NASA

8. Coastal prairies occur in a patchwork with scrub and forests • Continued disturbance maintains prairie species composition and extent (with a caveat) • Disturbance processes include grazing, fire, digging, wallowing—not interchangeable

9. California’s Coastal Prairies Support: • Approximately 40% of California’s native plant species (Wigand 2007) • An incredibly rich flora, including 80 endemic species (Ford and Hayes 2007) • Long-lived perennial bunchgrasses (e.g. Festucacalifornica, F. idahoensis, Danthoniacalifornica): some are over 200 years old Source: sonoma.edu/preserves/prairie Photo Credit: National Park Service

10. California’s Coastal Prairies Support: • Over 30% of the diversity of vegetation types in Sonoma and Marin Counties • The most biodiverse grassland in North America—more than twice the species found in areas of the Great Plains (Stromberg, et al. 2001; Wigand 2007) Source: sonoma.edu/preserves/prairie Photo Credit: National Park Service

11. California’s Coastal Prairies: Carbon Sequestration • Obligate summer dormancy of perennial bunchgrasses: maintains carbon pump even in the absence of other disturbance (e.g. Zhou 2012) • Soil organic matter of Marin coastal prairies is approximately 50% carbon • Certain short-rotation, intensive grazing practices increase the amount of carbon removed from the atmosphere and stored in the soil (Jasper 2008) Source: sonoma.edu/preserves/prairie Photo Credit: National Park Service

12. California’s Coastal Prairies: Erosion • Deep-rooted perennial grasses capture, filter and store water, anchoring the soil in place • Perennial grasses provide erosion control throughout the year, long after annual plants die • Perennial grasses take advantage of early autumn rains, greening up and absorbing water before the annual seeds have a chance to germinate. Source: sonoma.edu/preserves/prairie Photo Credit: National Park Service

13. Grassland birds are the most threatened group of birds in the United States (Rao, et al. 2008). Source: sonoma.edu/preserves/prairie Photo Credit: Wikimedia Commons

14. Grassland birds (e.g. grasshopper sparrow and savannah sparrow) need open spaces between bunchgrasses to forage and build their nests. Prairies dominated by invasive annuals, with few native bunchgrasses, are poor habitat for grassland birds (Grassland Birds Need More than Grass, Hastings Natural History Reserve). Source: sonoma.edu/preserves/prairie Photo Credit: Jim Coleman

15. Wildflowers that grow among grasses are an essential food source along with the insects that the plants attract • Poorly managed grazing can destroy nests by trampling and reducing protective cover (Unitt 2008) Source: sonoma.edu/preserves/prairie Photo Credit: Jim Coleman

16. Grassland Wildlife Resources: Raptors • Northern Harrier (nesting sites, hunting areas) • Red-tailed Hawk (hunting areas) • White-tailed Kite (hunting areas) Source: sonoma.edu/preserves/prairie Photo Credit: Wikimedia Commons

17. Invasive species, land development, and other human-related activities have reduced California’s coastal grasslands by 90%. California grasslands are among the most endangered ecosystems in the United States (Noss and Peters 1995). Source: sonoma.edu/preserves/prairie Photo Credit: D. Immel-Jeffery 2010

18. Coastal Prairie Threats • Habitat Conversion and Fragmentation • Invasive Species • Reduced Disturbance • Altered watershed hydrology • Limited knowledge and under-appreciation • Air pollution • Climate Change Source: sonoma.edu/preserves/prairie Photo Credit: K. Kraft 2009

19. Over 24% along California’s north (Bay area) coast has been urbanized, the most of any other major plant community in the United States(Ford and Hayes 2007; Loveland and Hutcheson 1995) Source: sonoma.edu/preserves/prairie Photo Credit: K. Kraft 2009

20. Nitrogen deposition from auto exhaust has been linked to the increase of Italian ryegrass (Festucaperennis) in serpentine grasslands in the Bay Area (Harrison and Viers2007) • Nitrogen pollution can negatively affect microbial activity, decreasing the rate of decomposition of organic matter • Automobile pollution from Highway 101 has been cited as a threat to the endangered Checkerspot butterfly (Eilerin 2006). Source: sonoma.edu/preserves/prairie Photo Credit: K. Kraft 2009

21. Invasive Species • Form monocultures • Decrease biodiversity • Alter vegetation structure • Impact ecosystem processes • Impact rare or endangered species • Threaten wildlife resources* • Threaten rare or endangered ecosystems Source: sonoma.edu/preserves/prairie Photo Credit: Wikimedia Commons

22. Many non-native, annual grasslands still harbor a variety of native species, depending on their use history. The proportion of native plants can range up to 50% or more (Biswell 1956). • Annual grasslands continue to be utilized by grassland dependent birds and other animals (CPEFS 2010; Ford and Hayes 2007; Kie 2005). Source: sonoma.edu/preserves/prairie Photo Credit: Ryan DiGaudio

23. Invasive Species: Ecosystem Engineers • Create conditions that increase their own survival while reducing that of their competitors • Conditions persist even after the invasive species is removed (e.g. soil chemistry changes, hybridization with native species, hydrological changes) Source: Wikimedia Commons

24. REDUCED DISTURBANCE: Grazing , Fire, Digging

25. GRAZING By the late Pleistocene (10,000 BP to 1.6 MYBP), California grasslands supported one of the greatest wildlife assemblages on the Earth. The diversity and abundance of pre-historic grazers, browsers, predators and scavengers may be one of the greatest in the world exceeding that of East Africa (Edwards 2007).

26. Zebras: (Dolichohippus sp.) , (Pliohippussp.) Horses : Giant horse, Western horse, Three-toed horse Llamas: Large-headed llama Deer: Brachyodont deer, Mule deer, Elk Pronghorns: Pacific pronghorn, antelope or four-horned pronghorn, Pronghorn Oxen: Shrub ox, Woodland musk ox Mammoths: Columbian mammoth, American mastodon Sloths: Harlan’s ground sloth, Shasta ground sloth, Jefferson’s ground sloth Bison: Ancient or Ice Age bison Camels: Large or western camel Tapirs: Tapir Pigs: Flat-headed peccary

27. SOIL DISTURBANCE Examples: Gophers, Bears, Pigs, Ground Squirrels, Insects Caveat: These species are also grazers!!! At a density of 23 per acre, Botta’s pocket gophers decreased the forage yield by 25% in annual-dominated rangelands in the California foothills. (Case 2008)

28. GOPHERS • 4 to 18 inches below the surface, deeper branches 5 - 6 ft • up to 200 yards of tunnels • up to 300 soil mounds per animal per year • up to 2 1/4 tons of earth moved per gopher each year • up to 46 3/4 tons per acre per year for a population of 50 pocket gophers • Tend to increase in ungrazed sites • (Case 2008)

30. Grazing Adaptations • Stimulates growth of tillers, rhizomes and stolons • Detachable stems transported (with uneaten seed) to new areas—example: Danthoniacalifornica • Seeds germinate when trampled into the ground • Seeds take advantage of grazers’ fertilizing manure

31. FIRE

32. Fire prevents invasion by trees and shrubs Grey Hayes citing: Hatch, D. A., J. W. Bartolome, J. S. Fehmi, and D. S. Hillyard. 1999

33. Fire affects grass species differently Grey Hayes citing: Hatch, D. A., J. W. Bartolome, J. S. Fehmi, and D. S. Hillyard. 1999

34. Effects of Fire on Coastal Grasslands • Removes thatch, shrub seedlings, and tree seedlings • Recycles nutrients • Destroys pathogens • Creates openings for grassland species • Increases flowering among some species (e.g. Chlorogalumand Brodiaeaspp.) • Caveat: fire effects depend on fire intensity, frequency, pattern and season

35. GRAZING, FIRE & SOIL DISTURBANCE • Shrub clearance • Tolerant grassland species

36. DISTURBANCE THEN AND NOW Significant environmental changes: Invasive species Nitrogen Habitat patchiness Climate Disturbance processes will have different effects because the environment has changed