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Royce Larsen UC Cooperative Extension

Royce Larsen UC Cooperative Extension. The Cattle, The Stream & The Fish. Ranching and Riparian Corridors Workshop April 10, 2007.

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Royce Larsen UC Cooperative Extension

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  1. Royce Larsen UC Cooperative Extension The Cattle, The Stream & The Fish Ranching and Riparian Corridors Workshop April 10, 2007

  2. There is a massive environmental debt to repay in California, which is reflected in the degraded nature of so many of our streams, lakes, and estuaries. We can fix things now, or we can wait until conditions get worse and we experience even more strongly the loss of benefits provided by healthy ecosystems. (Peter B. Moyle)

  3. Watersheds Degradation can come from many sources. USDA NRCS

  4. Cattle Are Just One Possible Source • Some impacts cattle can cause are: • Bank Erosion • Down Cutting • Wider/Shallower Streams • Higher Water Temperature • Decreased Fish/Aquatic Value

  5. Theresa A. Becchetti Riparian Grazing Strategies Kenneth W. Tate, Edward R. Atwill, David F. Lile, Don L. Lancaster, Neil McDougald, Sheila Barry, Roger S. Ingram, Holly A. George, Wayne J. Jensen, William E. Frost, Royce Larsen, Ralph Phillips, Mark Horny, John Harper, Gary G. Markegard, Stephanie Larson, Rick Delmas, James Farley, Larry Forero UCCE Rangeland Watershed Group

  6. Grazing and Riparian Health?

  7. Background • Review of literature base (Allen-Diaz et al. 1999, Belsky et al. 1999, Larsen et al. 1998, Rinne 1999). • No stocking rates, physical characteristics, or grazing system defined. • Experiments compare “grazing” to “no grazing”. • Sparse information on direct links of “grazing” and fisheries.

  8. Background • Lacking in literature: • Toolbox of tested, site-specific grazing recommendations. • Needs: • Data driven, management scale project to identify feasible grazing management that enhances riparian resources.

  9. Riparian Grazing Project • Objectives: • Cross-sectional survey of California’s rangeland riparian areas. • Identify grazing management and site characteristics associated with high and low “riparian health”. • Synthesize data for site specific recommendations. • Publish and extend information. • Utilize sites to develop set of case studies.

  10. Study Sites

  11. Survey Tools Hydrologic Condition Habitat Assessments Site Characterization Management Survey EPA NRCS BLM

  12. Habitat Features Undercut Banks LWD Clean Riffles Pools Included measurement of LWD, riffles, pools, etc.

  13. Hydrologic Function Width Depth Bank Stability Headcuts Entrenchment Includes measurement of entrenchment, width/depth ratio, bank stability, etc.

  14. Physical Characteristics Included measurement of width, depth, etc.

  15. Management Practices: • Growing Season Grazing (Early, Late, or Entire Season, Dormant Season) • Stock Density (Number of head per acre) • Animal Unit per Acre per Year (No. of animals/acre/year) • Rest Provided (Yes/No) • Rest Between Grazing (Days) • Frequency (Number of times per year pasture is grazed) • Herding (Man Days per Year) • Off-Site Attractant Provided (Yes/No) • Off-Site Attractant Time (Man Days per Year) • Fencing (Yes/No) • Fencing Time (Man Days per Year)

  16. Analysis • Examine current management practices at various levels of detail using multivariate regression analyses

  17. A and B Streams Steep gradient Limited Floodplain Bedrock and Boulder

  18. C and E Streams Low Gradient Large Floodplain Lots of Meanders

  19. Results: Level 1- Both seasons and all streams. Model = 15.73 – 0.248(Stock Density) – 0.332(Frequency) + 0.003(Rest Between Grazing) +0.024(Herding) + 0.046(Off-Site Attractant Time) + 0.111(Frequency*Stock Density) n=128,R2 = 0.20

  20. Results: Level 2, summer growing season Model = 14.04 + 0.006(Rest Between Grazing) + 0.043(Herding) + 0.066(Off-Site Attractant Time) n=75, R2 = 0.19

  21. Results: Level 2, winter growing season Model = 16.63 – 0.353(Stock Density) n=55, R2 = 0.10

  22. Results: Level 3, summer growing season CE-stream types Model = 13.85 + 0.007(Rest Between Grazing) + 0.043(Herding) + 0.088(Off-Site Attractant Time) n=67, R2 = 0.24

  23. Results: Level 3, winter growing season CE stream types Model = 15.70 – 0.030(Stock Density) n=20, R2 = 0.18

  24. Conclusions • Underlying factors interact with management regimes. • However- we are identifying feasible grazing management practices

  25. Intermittent, Annual Grassland Dominated Streams Treatments NG = No Grazing DSM = Dry Season Moderate DSC = Dry Season Concentrated WSM = Wet Season Moderate WSC = Wet Season Concentrated Treatment target Concentrated = RDM < 600 lb/ac Moderate = RDM ~ 1000 lb/ac SJER

  26. Conclusions Depth most important parameter for statistical analysis. Max. depth increased in reaches protected from grazing. Livestock impacts were small and hard to detect and difficult to separate from other effects. Each stream reach responded differently to grazing treatments.

  27. ? Riparian Health? Art? – Science? – Both? Domestic Livestock vs Other Ungulates? Perceptions

  28. Example: Buffalo in Yellowstone Park. Bank damage Over grazing Etc. They are native and in the park so it is accepted?

  29. Are domestic animals accepted? The real question should be: Is it the cow? Or the stream? Or the management?

  30. Season long grazed 100+ years, Currently 25 cows/calves Jun, Jul, Aug Willows sprayed in 50’s 100+ year event 1964 2 years rest, changed grazing to Feb, Mar, Apr. Bear Creek May 1977 Baltic rush

  31. Increase in rushes, sedges beginning. Wet and dry year cycles needed to build banks, etc. 6 years Bear Creek May 1983

  32. Flood plain continued to develop. Nebraska sedge, small-fruit bullrush, beaked sedge, spike rush, brook grass, three square bulrush, reed canarygrass Bear Creek Aug 1986 9 years

  33. Vegetation and banks continued to improve, increased water storage, improved energy dissipation capabilities Bear Creek Oct 1988 11 years

  34. 75 year event. 18.5 years Bear Creek Feb 1996

  35. Small storm events bring sediment, help shape the channel floodplain. Bear Creek Sept 1997 20 years

  36. Banks and vegetation continued to improve, narrower and deeper. Aquatic thermal environment improved, both winter and summer. It was 15 degrees F, no ice when picture taken. Summer water temp was 20-25 degrees cooler. 22.5 years Bear Creek Dec. 2000

  37. Drought year, but stream still flowing. Bear Creek May 2003 26 years

  38. 1977 2001 1983 Bear Creek : Change In Channel Profile (1977 – 2001) 2001 1983 104 102 100 1977 98 96 94 92 90 88 120 145 170 195 220 235 240 100 105 110 115 125 130 135 140 150 155 160 165 175 180 185 190 200 205 210 215 225 230

  39. Bear Creek(3.5 Miles) Grazing increased from 75 AUM’s to 250 AUM’s Data from C. Rasmussen (1996) and W. Elmore

  40. June , 1804 Lewis & Clark Expedition Confluence of the Missouri And Kansas Rivers. June 17, Clark wrote “The party is much Aflicted with boils and several have the decissentary which I conrtribute to the water which is muddy… The surface was full of scum, mud and debris; if the men dipped deep they would get cleaner water. June 24, Lewis weighed the water of the two rivers and found the Missouri’s to be heavier, meaning it carried more mud. Stephen E. Ambrose; Undaunted Courage

  41. Lewis & Clark Expedition 1804 – 1805 Nebraska - Montana The Indians used fire to burn the old dry grass to encourage the new grass to feed their horses and entice the buffalo. Immense herds of buffalo, elk, deer, and antelope were noted many times. Stephen E. Ambrose; Undaunted Courage

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