4/18/2011. Low and open structure dominated by scrub oaks Vegetation mosaic with open sandy patches < 15% pine overstory

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1 Habitat, Demography, and Management for the Florida Scrub Jay: Is it an appropriate umbrella species? Was it good for you too? Florida Scrub Jays are sensitive to habitat structure and species composition Low and open structure dominated by scrub oaks Vegetation mosaic with open sandy patches < 15% pine overstory Suitable for Florida Scrub Jays and capable of producing surplus, ie i.e. source demographics 1

2 Habitat structure has a strong influence on the demography of Florida Scrub Jays Deviatio on from Lamda = Source Sink -1.0 Short Optimal Tall Mix Tall Breininger et al Chronological response of FSJ populations to fire 7 Unit 18E, Archbold Biological Station 6 es Scrub-Jay Territori # years 1 0 FIRE FIRE Year 2

3 Chronological response of FSJ populations to fire Relative Quality Optimal Dispersers tat ure Jay Dispersal Refugees X X Refugees Habit Struct Years Since Fire Fitzpatrick, Woolfenden and Bowman 1999 Florida Scrub Jays are sensitive to habitat structure and species composition Low and open structure Dominated by scrub oaks Vegetation mosaic with open sandy patches < 15% pine overstory Suitable for Florida Scrub Jays and capable of producing surplus, ie i.e. source demographics What are the challenges to get from current conditions to desired conditions and maintain FSJ populations as well as viable populations of other scrub endemics? 3

4 Fire management for FSJs that maximizes biodiversity A good maintenance burn will not be 100% Fire management for FSJs that maximizes biodiversity Allows for potential refuge Immigration 4

5 Fire management for FSJs that maximizes biodiversity Some nest sites still remain Immigration Does fire management that benefits FJSs benefit other scrub endemics? Dicerandra frutescens, Lake Placid Scrub Mint 1.00 Optimal Fire Return Interval: 5 12 years Extinction Probability Menges et al Biological Conservation Fire Return Interval Quasi-Extinction Threshold 1 Quasi-Extinction Threshold 10 Quasi-Extinction Threshold 100 5

6 Does fire management that benefits FJSs benefit other scrub endemics? Species Dicerandra frutescens Eriogonum longifolium Eryngium cuneifolium Hypericum cumulicola Lechea, Polygonella spp Best FRI Ext. time w/o fire Citation Menges et al Biological Conservation <5 100 s Satterthwaite et al Ecological Applications < Menges and Quintana-Ascencio Ecological Monographs < s Quintana-Ascencio et al Conservation Biology --- Little effect of fire Maliakal et al. In preparation Does fire management that benefits FJSs benefit other scrub endemics? Sand Skink Abundance increases with time since fire, > 17 yrs > genetic diversity in long unburned habitat Mushinsky et al 2010, Schrey et al 2011 Gopher Tortoise In scrub, burrow density increased with number of fires and decreased with time since fire Ashton et al Most common in scrub kept open by fire Branch et al Scrub Lizard 6

7 Does fire management for FJSs benefit other scrub endemics? Florida Scrub Jay Sceloporus Gopherus Neoseps Approximate fire return intervals ideal might persist Hypericum Eryngium Dicerandra Eriogonum 1 year 10 years 100 years Time since fire Does fire management for FJSs benefit other scrub endemics? Yes, but pyrodiversity rules! Pyrodiversity = biodiversity Pyrodiversity = bet hedging Florida Scrub Jay Sceloporus Gopherus Neoseps Hypericum Eryngium Dicerandra Eriogonum 1 year 10 years 100 years Time since fire 7

8 How do you measure the success of restoration? If you build it, will they come? Habitat structure and composition low and open oaks little or no overstory The ability to use fire alone to maintain habitat quality restoration management completed Increased biodiversity of native species But what determines whether a species is present or not? Even if you restore it, some species may never be present Landscape connectivity Source populations NO SINGLE SPECIES CAN BE AN INDICATOR OF SUCCESS Demographic Population Structure: metapopulations Ocala NF 21 viable metapopulations Based on maximum Merritt Island dispersal distance ~12 km All highly fragmented As patches get smaller and more isolated, the probability of immigration and Lake Wales Ridge colonization decrease 8

9 Demographic Population Structure: Genetic units Ocala NF 11 distinct genetic units Several encompass >1 metapopulation Merritt Island Result of limited gene flow because of short dispersal and changes in habitat mosaic Genetic units now recognized as the units for recovery, but most Lake Wales Ridge span jurisdictional boundaries Coulon et al 2008 Molecular Ecology Independent of habitat quality, Population persistence depends on size and isolation But if these populations occur within a network of connected reserves, these extinction risks are substantially smaller 9

10 Estimates of scrub and jay populations on managed lands of southeast Florida County Site Scrub (acres) Jays (groups) Potential Palm Beach Hypoluxo ~ ~3 Juno Dunes ~ ~10 Jupiter Ridge ~ ~5 Radnor ~80 1 ~2 Martin Atlantic Ridge Eco ~120 4 ~4 Atlantic Ridge SP ~20 1 ~1 Hobe Sound ~320 0 ~9 Jonathan Dickinson ~ ~78 Sea Branch ~570 0 ~16 St. Lucie Savannas Preserve ~730 7 ~20 Estimates of scrub and jay populations on managed lands of southeast Florida County Site Scrub (acres) Jays (groups) Potential Palm Beach Hypoluxo ~ ~3 Juno Dunes ~ ~10 Jupiter Ridge ~ ~5 At Risk Radnor ~80 1 ~2 Martin Atlantic Ridge Eco ~120 4 ~4 Atlantic Ridge SP ~20 1 ~1 Hobe Sound ~320 0 ~9 Jonathan Dickinson ~ ~78 Sea Branch ~570 0 ~16 St. Lucie Savannas Preserve ~730 7 ~20 10

11 Estimates of scrub and jay populations on managed lands of southeast Florida County Site Scrub (acres) Jays (groups) Potential Palm Beach Hypoluxo ~ ~3 Juno Dunes ~ ~10 Jupiter Ridge ~ ~5 Radnor ~80 1 ~2 Martin Atlantic Ridge Eco ~120 4 ~4 Atlantic Ridge SP ~20 1 ~1 Hobe Sound ~320 0 ~9 Jonathan Dickinson ~ ~78 Sea Branch ~570 0 ~16 St. Lucie Savannas Preserve ~730 7 ~20 At Risk Adequately Protected Why save scrub if not for jays? Biodiversity maintaining thepopulationsand and communities and the biotic and abiotic processes that define the ecosystem maintaining the ecosystem services that help sustain us 11

12 Why save scrub if not for jays? Building our Future Education Species awareness Fire awareness Conservation awareness 12