Decisions, Decisions: Grass Invasions & Altered Wildfire Regimes in the
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Decisions, Decisions: Grass Invasions & Altered Wildfire Regimes in the American Deserts Julio Betancourt USGS Tucson August 2, 2009 ESA Annual Meeting Climate Change & Restoration Workshop Albuquerque Principal Invasive Grasses Fueling Wildfires in the American Deserts Schismus arabicus Schismus barbatus Mediterranean grass Bromus tectorum cheatgrass Bromus madritensis var. rubens red brome Pennisetum ciliare buffelgrass The Grass-Fire Cycle Average fire size Invader Abundance, Fuel Connectivity & Wildfire Size Nonlinear due to increasing connectivity Invader Abundance (Time) Recent Invasives-Driven Wildfires in the Western U.S. Fire Desert Year State Size Murphy Complex Great Basin 2007 Nevada/ Idaho 653,000 acres Milford Flat Complex Great Basin 2007 Utah 363,000 acres Winters Fire Great Basin 2006 Nevada 238,000 acres Southern Nevada Mojave Complex 2005 Nevada 735,000 acres Cave Creek Complex 2005 Arizona 248,000 acres Sonoran Expansion and Logistic Growth Curve for Red Brome in western North America (Salo 2005 Biological Invasions) 160 140 Fast 1976-1998 Cum. New 50-km Areas 120 Slow 1943-1975 100 80 Fast 1930-1942 Bromus madritensis var. rubens 60 PDO 40 Y=7.39+124.11/(1+EXP(-(X-1936.3)/10.29)) DF Adj r2 = 0.979 Inflection = 1936.3 20 0 1890 1910 1930 1950 Year 1970 1990 2010 Grassland/shrubland fires have different climatologies than forest fires. With increasing frequency, size and intensity of invasives-driven fires, expect desert fires to become forest fires, and fire climatologies to change. Grass/Shrub fires FOLLOW WET years Forests burn DURING DRY years Years before Fire Year of Fire Courtesy of Tony Westerling, UC-Merced Ignition front, Beatty Fire 2006 Grass Invasions are changing the relationship between climate and fire in the West 2005 2002 Log of Annual Area Burned in FS Region 3 (AZ + NM) during El Niño vs. La Niña years Swetnam, T. W., and J. L. Betancourt. 1990. Fire-Southern Oscillation relations in the southwestern United States. Science 249:1017-1020 June 2005 Cave Creek Complex Fire, AZ 248,000 acres July 2006 Southern Nevada Complex 735,000 acres Decisions, Decisions… Do we save the deserts or resign ourselves to these combustible grasslands? Which species do we control and which desert do we save? Who makes this decision, with what consensus and authority? How do we overcome political obstacles & garner political will? How much will this cost and what are we willing to pay? Who bears the cost and responsibility? What framework do we use to organize ourselves? How do we know if we are failing or succeeding? How long is our commitment? If we fail or decide to do nothing, how will we adapt? Santa Catalina Mts The Foothills:Tucson’s “Beachfront”Property Saguaros imbedded in flammable buffelgrass on south slope of Catalina Mts Saturation Phase Quarantine Eradication Priority Priority Stage Stage Control Priority Stage Effective Control Unlikely without Massive resource Inputs Fire Colonization Phase Expansion Phase Time Control costs Invader abundance Gotta know where you are? Gotta Prioritize and Fund the Right Science • Mapping, monitoring, and remote sensing • Decision support and economic analysis • Control methods- Life cycle of treatments • Habitat suitability models & sensitivity simulations • Fuel load & fire spread models • Post-fire restoration • Long-term effects of invasion & forecasting of environmental consequences should mitigation fail • Ecological & economic benefits of invasive • Political ecology: Policy and practices Gotta be able to herd cats! Gotta Engage the Business Community! Inside Tucson Business, April 6, 2009 Courtesy of Wes Hargis Gotta have deciders! • Sarah Smallhouse, Pres., T. R. Brown Foundations • Jim Kiser, VP, So. Arizona Leadership Council • Erik Bakken, VP, Tucson Electric Power • Lisa Lovallo, VP, Cox Communications-SoAz • Teresa Olson, Tucson Assoc. of Realtors • Chuck Huckelberry, Pima County Administrator • Mike Letcher, City Manager, City of Tucson • Claire Zucker, Pima Association of Govt’s • Tom Brandhuber, Fire Chief, Pima Rural Metro • Lisa Graumlich, SNR, University of Arizona • Carolyn Campbell, Coalition for Sonoran Desert Protection • Marilyn Hanson, Sonoran Desert Weedwackers • Rick Brusca, Arizona-Sonora Desert Museum • Julio Betancourt, U. S. Geological Survey • Darla Sidles, Supt., Saguaro National Park • Jeanine Derby, Sup., Coronado National Forest • Michael Taylor, Deputy Director, BLM, AZ Gotta have a Plan! http://www.buffelgrass .org • Minimize spread in areas where buffelgrass not yet established • Implement control priorities based on actual & potential impacts • Restore treated areas in ways that increase resilience against future invasion • In areas where control is no longer feasible, mitigate fire risks to life & property • Motivate legislation aimed at sustaining the control effort • Create a template for invasive spp mgmt in AZ Gotta have a Framework! Step 1: Define the decision support domain, including management objectives and potential alternative management strategies Weed Management Strategies Examples: Bio-control Chemical treatment Mechanical removal Fire Management Strategies Examples: Fuel reduction Fire breaks Prescribed burns Step 2: Measurement & Modeling • Monitoring of existing infestations and previous fires • Mapping of potential habitat • State and Transition model for control efforts, fire and invasions (Including explicit modeling of uncertainties) • Modeling of the impacts of potential management strategies on: State & transition models Management objectives Management Objectives Examples: • Increase capacity to sustain military training and testing • Maintain habitat of listed and at-risk species • Enable appropriate and achievable recovery of degraded ecological systems. Step 3: Integrated decision support modeling Step 4: Decision-making, implementation, and adaptive management • Use the decision support tool to select one or more strategies for specific management objectives. • Implement those strategies within a program of careful monitoring and management. • Adapt the management strategies and update the decision support models based on what is learned through implementation and monitoring. Gotta have the right tools to make informed decisions Tumamoc Hill, Tucson Static Treatment CostEffectiveness Weighted Potential Damage Equal weighting to ecological resources & infrastructure Reduction in damage index per $ of treatment Frisvold, Olsson, Orr, Bean & Betancourt, USDA-PREISM Gotta be able to chew gum & walk at same time Plan B: Adaptation: What we should start doing to minimize impacts as deserts become more flammable Plan A- Mitigation: What we must do to prevent deserts from becoming more flammable Gotta Have Appropriate Level of Funding TUCSON, Ariz. (AP) - A plan to spray a weed killer on buffelgrass has been scrapped by Pima County officials. The county had planned to use a helicopter to spray 12 roughly one acre sized parcels in a rugged area west of Kennedy Park near Ajo Way. However, County Supervisors grounded the operation because of safety concerns raised by the public. July 30, 2009 Gotta be able to quickly resolve conflicts Scientists have to reach reasonable consensus or be prepared to back up any dissent We tend to get "a little hysterical" about such things (i.e.,buffelgrass), it is too established and difficult to remove, and we should stop fighting it At the risk of sounding "hysterical," if we do nothing, in a few decades our fireproof desert will be overrun by flammable grass …The predictable costs of letting buffelgrass spread indefinitely will greatly exceed the price of controlling it now. How did increasing springtime temperatures affect grass invasions? http://doubletroublebulletin.wordpress.com The Double Trouble electronic news bulletin is published by the Australian Invasive Species Council as part of its Pests and Climate Change Project Aimed at convincing decision & policy makers of the urgent need to prepare for the combined dangers of climate change & invasive species Help increase awareness of the growing need to recognize invasive species as a major component of the climate change problem, Grass Invasions & altered wildfire regimes are well on their way to causing irreversible ecosystem transformation in the West This would probably would have happened with or without climate change Despite considerable & abrupt warming since 1980s, no changes in rates of invasion attributed to early stages of climate change We are failing miserably at managing grass invasions and associated wildfires Our goal should be to break the cycle between non-native invasive grasses and the fire regimes they promote Mitigate the adverse ecological effects that might result from the synergy of invasives, altered wildfire regimes, and climate change. Post-fire seeding after invasives-driven wildfires in the American deserts: Do we know what we’re doing? How should climate change affect our approach? Issues & Opportunities for the Seed Industry • Climate variability & climate change will affect opportunities for post-fire seeding and its success • Most successful seed ventures probably will be the ones that best assimilate short and long-lead climatic ecological forecasts and anticipate regional needs • Seed Tranfer Zones are going to change • Long-term success of post-fire seeding in the American deserts will require novel mixes of species, phenotypes, and genotypes adapted to future, not past, climates What Our Main Objectives Should Be • Break the cycle between non-native invasive plants and the fire regimes they promote • Mitigate the adverse ecological effects that might result from the synergy of invasives, altered wildfire regimes, and climate change.
