1 / 18

Disturbance Thresholds for Oregon

Disturbance Thresholds for Oregon. Evidence from the scientific community. The Problem. H ow much sage-grouse habitat can be altered? What baseline values can we use to regulate disturbance? Where can sage-grouse habitat be altered? When can sage-grouse habitat be altered?. Disturbance.

marcos
Download Presentation

Disturbance Thresholds for Oregon

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Disturbance Thresholds for Oregon Evidence from the scientific community

  2. The Problem • How much sage-grouse habitat can be altered? • What baseline values can we use to regulate disturbance? • Where can sage-grouse habitat be altered? • When can sage-grouse habitat be altered?

  3. Disturbance …”a relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or the physical environment” -- Pickett and White (1985: 7) Categories: • Physical(abiotic) • Biological (biotic) • Human (anthropogenic) • Natural • Discrete • Diffuse • Short-term • Long-term

  4. Disturbance Categories Physical (abiotic) Biological (biotic) Human Natural Diffuse Discrete Short-term Long-term

  5. Key Characteristics of Disturbance • Intensity • Frequency • Spatial scale (extent and distribution)

  6. Sage-Grouse and SagebrushSpace-time dimensions 100 Sage-Grouse range Management Zone Core areas Temporal scale (yr) Populations 10 Landscapes Habitat Sage-Grouse Leks Stands Management concepts Sites Disturbance space Shrubs Individuals 1 1,000 0.1 1,000,000 1 Spatial scale (km2)

  7. Thresholds 3%??

  8. Knick et al. 2013 • >3,200 leks across 6 states • 90% of leks had >40% sagebrush cover in landscape (mean cover around active leks >78%) • 99% of active leks were in landscapes with <3% developed

  9. Landscape Thresholds 40% 70 % Matrix Sagebrush

  10. Disturbance 3 % 5 % Matrix Sagebrush

  11. Landscape Thresholds 37% 65 % Matrix Sagebrush

  12. Birds occupy big, flat and undisturbed sagebrush landscapes Baruch-Mordo et al., in press

  13. Sage-grouse do best in landscapes with >70% sagebrush “Sagebrush from horizon to horizon”

  14. Sage-grouse have trouble persisting in landscapes with <40-50% sagebrush (Knick et al. 2013, Wisdom et al. 2011)

  15. Oregon Core Areas = 90% of birds on 38% of the range

  16. Take home points • Sage-grouse are highly aggregated • Multiple factors are related to lek persistence and could be used turned into thresholds, but human disturbance is being used by others • Research suggests that sage-grouse do not tolerate much habitat loss (Knick et al. 2013, Karl and Sadowski 2005, Wisdom et al. 2011) • 5% rule in Wyoming based on the footprint of a wellpad in a 1 sq. mile section (Naugle, Doherty) • 70/30 ODFW ratio based on Karl and Sadowski 2005, as well as other studies

  17. Recommendations • Need to specify the extent for applying the disturbance threshold • Will it be at the core area? • Will it be range wide? • NTT used two extents • The fine scale helps define when mitigation might be engaged, what the mitigation should be, and where it should occur • Range wide extent ensures long-term persistence of habitat • Consider the disturbance regime when considering the extent(s) • Define the disturbances that will be included

  18. Extra slides

More Related