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Initial Baseline Assessment. SageCon Technical Team Theresa Burcsu, Lead tburcsu@pdx.edu. Contributors – Special Thanks!. TNC Mary Finnerty Michael Schindel Cathy Macdonald Garth Fuller Steve Buttrick NRCS Jeremy Maestas ODFW Dawn Davis Eric Rickerson USFWS Jeff Everett
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Initial Baseline Assessment SageCon Technical Team Theresa Burcsu, Lead tburcsu@pdx.edu
Contributors – Special Thanks! • TNC • Mary Finnerty • Michael Schindel • Cathy Macdonald • Garth Fuller • Steve Buttrick • NRCS • Jeremy Maestas • ODFW • Dawn Davis • Eric Rickerson • USFWS • Jeff Everett • Jodie Delavan • Angela Sitz • Dolores Weisbaum • Defenders of Wildlife • Bruce Taylor • Sara O’brien • BLM • Glenn Frederick • Rolando Mendez • Jeanne Keyes • OSU • Christian Hagen
Questions (June 2013) • What are the natural fire regimes for SE OR natural systems? • Are current conditions departed from this range? • Where is habitat susceptible to cheatgrass? • Where are “historic” stands of Juniper? • Where are Phase 1, 2, 3 juniper stands?
Habitat loss and fragmentation(July 2013) • A primary cause of sage-grouse population decline • Disturbances are associated with habitat fragmentation. • How do we manage for multiple objectives while conserving sage-grouse and preventing its listing?
Establishing acceptable levels of disturbance in sage-grouse habitat(July 2013) • Howmuch sage-grouse habitat can be altered? • Where can sage-grouse habitat be altered? • When can sage-grouse habitat be altered? • In other words: What baseline and maximum values can we use to regulate disturbance and its impacts?
Recent Meetings Review • Reviewed the threats to sage-grouse • Fire • Juniper • Cheatgrass/invasives • Causes of habitat fragmentation • Others • Reviewed research that analyzed and quantified threats, especially human disturbance • Developed questions to analyze the threats • Explored ways to quantify current conditions • Identified complexity of the problem • Began to chart a path forward
Since the last meeting • Developed key questions to assess current conditions • Researched disturbance policies in other states • Continued to compile and analyze agency and other data • Organized ongoing activities across agencies • Produced a candidate template to contain analysis results • Produced preliminary baseline maps as part of a disturbance threshold analysis for Oregon
Technical Challenges to a Flexible Policy • Sage-grouse are sensitive to disturbance at low levels 0.3% “Slippery slope” Leks 3% - 4% Developed land
Technical Challenges, cont. • Identifying the right unit(s) based on biology and ecology is challenging. • The size of the assessment unit for calculating existing conditions and a baseline • Larger units are good for regional planning efforts, but not good for project or site level assessments. • As units get smaller, flexibility decreases (Bruce – help here) • Identifying the right unit(s) based on biology and ecology is still elusive.
Management Challenges • Success rates for recovering/improving sagebrush habitat are low. • Sagebrush habitats take more than 20 to 30 years to mature; sage grouse use may take even longer to recover at a disturbed site. • Due to sage-grouse’s fidelity to sites, birds may continue to return to leks many years after habitat disturbances occur – giving a false impression of their ability to withstand disturbance.
Policy Challenges • The simplest solution - a single cap - is likely to lead to unacceptable impacts in relatively intact areas • The “sweet spot” between flexibility and species protection is small.
Goals • Identify existing conditions for sage-grouse at the time of the candidate species decision (2010)* • Inform the policy framing efforts by determining if there is flexibility in core habitat * Based on key landscape attributes: developed land, sagebrush, conifers, agriculture
Related Questions • What are the most important biological factors and considerations for refining current sage-grouse policy? • What geographic information can be used to refine current sage-grouse policy? • What are the most useful spatial scales for refining sage-grouse policy? • Are the spatial scales used for policy refinement also the best scale for implementing the policy?
Subtasks and requirements • Replicate lek-scale analysis by Knick et al . (2013) using more current data (5 km buffers) • Correctly classify leks as “active” or “historic” • Correctly classify land cover classes • Identify additional important spatial units and scales for analysis of existing conditions (e.g., BLM districts, population boundaries) • Ensure that identified spatial units can be linked to policy framing and implementation • Ensure appropriate use of data
Key Outcomes • Identified preliminary set of criteria for identifying important ecological and political spatial units • Mapped distribution of sagebrush, development, and agriculture across OR range • Related percentages of sagebrush, development, and agriculture to core polygons
Next Steps • Revise classification of leks (active/historic) • Prioritize spatial units for analysis and policy-framing • Refine existing conditions analyses based on high priority spatial units • Perform past conditions assessment (2001) • Assess conservation and restoration measures (CIG, other projects)
Planned Analyses • Current conditions – aka “Baseline” • Past conditions • Future trends
Methods • Acquire data • Land cover data • Lek locations • Boundaries • Group land cover classes into key landscape attribute classes: • Sagebrush, development, agriculture • Map distribution of key landscape attribute classes.
Insert graphic illustrating what land cover data look like • Inset map of a close-up of the contents of a lek buffer
Methods, cont. • Develop 5 km lek buffers – produces circles around leks • Overlay lek buffers (or other boundary) on land cover data. • Count the cells in each class. • Calculate the percentage of each class based on the size of each assessment unit (e.g., BLM district or lek buffer) and the class cell counts.
Methods • Data sources • ODFW lek locations • LANDFIRE Existing Vegetation (2010, released in 2013) • GEOMAC: Fire perimeters (same source as BER) • BLM: District boundaries • GEO: County boundaries
Selected Landscape Characteristics Knick et al. 2013, excerpt from Table 2
Selected Landscape Characteristics Knick et al. 2013, excerpt from Table 2
Maps • Spatial distribution of agriculture and development relative to sage-grouse habitat and leks
Agriculture • Data source: LANDFIRE 2010
Sagebrush Habitat Types • Data source: LANDFIRE 2010 • Doesn’t include understory • Different data sets may paint different pictures • Compared to ILAP data these numbers are higher • Add questions marks to where 2012 fires occurred.
Development • Data source: LANDFIRE 2010 • How does this relate to BER?
Leks and breeding complexes • ODFW lek database can be partitioned by “complexes” • Many leks are not in complexes. • Some leks look like they should be complexes (see Grassy Ridge inset)
Trial Balloon Proposal • Conservative threshold with future increases tied to: • Stable or Increasing population numbers; and • Documented effectiveness of offset actions based on: - population response to restoration treatments; • effectiveness of threat reduction measures • Consider setting thresholds by type of development (e.g. agricultural conversion, roads versus transmission versus solar) • Consider applying a disturbance allowance to all Core Habitat or a percent of Core Habitat
Base Facts • Current Core Policy on avoidance of core habitat affects 28% of the current range in Oregon; 72 percent of the range has option for offsetting impacts from unavoidable impacts. • 1 percent of a 4 miles buffered lek 80 acres of direct impact (habitat conversion).