Invasion of redhaired pine bark beetle into the Southern California National Forest system following fires

Transcription

1 Invasion of redhaired pine bark beetle into the Southern California National Forest system following fires Deguang Liu Tom Coleman Mary L. Flint Steve Seybold Photo by A.G. Gutierrez and D.N. Thomas Principal Target Species = RPBB

2 Fires A constant threat to forests and homes in the arid West (e.g., 6000 fires in CA in 2003, 400k acres burned, cost $970 million) Significantly alter the structure of forest arthropod communities Weaken the physiological defense mechanism of trees, and make trees more susceptible to bark and woodboring beetles including invasive species CDF 2007; McCullough et al. 1998; Boulanger and Sirois 2007

3 Invasive species Over 360 alien insect species have become established in American forests Approximately 30% of them are now serious pests Annual losses attributed to alien invasive forest insects is about $2.1 billion per year Pimental et al Redhaired pine bark beetle Mediterranean pine engraver

4 No. invasive scolytids established in California No. invasive bark beetles Before Penrose et al. 2009

5 Native distribution of Redhaired Pine Bark Beetle (RPBB) Also introduced into Australia, Japan, New Zealand, S. Africa, Sri Lanka, Chile, Brazil, Uruguay

6 Hosts Found on Aleppo (P. halepensis) and Canary Island (P. canariensis) pines and others Reported to attack most Pinus spp

7 Colonization and reproduction Prefer log surfaces in contact with moist soil Base of tree or in exposed roots A female lays up to 500 eggs in a gallery

8 Redhaired Pine Bark Beetle (RPBB)

9 How far has RPBB invaded into southern California national forests?

10 RPBB and Fires

11 Methods: site selection Twelve paired plots selected Time since fire: Old ( ) vs. Recent ( ) Extent of fire: Large (>1000 acres) vs. Small (<1000 acres)

12 Survey Plots in the San Bernardino National Forest (O,S) (R,L) (R,L) (O,L) (R,L) (R,S)

13 Barton Flats Fire, SBNF An example of a recent (July, 2005), small (70 acres) fire Burned Unburned

14 Butler II Fire, SBNF An example of a recent (Sept. 2007), large (14,000 acres) fire Burned Unburned

15 Survey Plots in the Angeles and Cleveland National Forests (R,L) (O,L) (R,S) (O,L) (O,L) (O,L)

16 Methods: traps Funnel traps (3/plot) and pitfall traps (3/plot) Funnel trap Pitfall trap

17 Methods: baits Background: Response of RPBB to α pinene and ethanol at three locations in Los Angeles Co. from 2006 to 2007 (low elevation sites) ( )-α-pinene + ethanol c C Ethanol a A ( )-α-pinene b B Unbaited Male a A Female Mean No./trap/wk (+SE)

18 RPBB seasonal flight activity, April, 2006 through April, 2007 (Los Angeles Co.) Apr 27-Apr 4-May 11-May 18-May 25-May 1-Jun 8-Jun 15-Jun 23-Jun 7-Jul 28-Jul 25-Aug 2-Oct 17-Oct 27-Oct 21-Nov 13-Dec 28-Dec 17-Jan 30-Jan 19-Feb 5-Mar 14-Mar 20-Mar 5-Apr 16-Apr Date % Maximum response

19 Preliminary results Comparisons on mean catches (mean ± SE /trap/sampling period) of bark and wood-boring beetles between burn and unburned sites in national forests of Southern California Taxa Burned Unburned Hylurgus ligniperda 0.7 ± ±0.1 Xyleborinus saxeseni 4.1 ± ± 0.6 Arhopalus syriacus 0.3 ± ± 0.1 Cerambycid beetles 0.5 ± ± 0.2 combined Scolytid beetles combined 6.4 ± ± 0.7

20 Summary The extent of establishment of RPBB and other invasive insects in the southern California National Forest System The relationships among insect responses, postfire interval, and extent of wildfire The baseline response of native forest insect fauna to wildfire

21 We acknowledge: C. Burnett and T. Persons for their assistance with sample collections Z. Heath (USDA FS FHP) for making maps used in the project A. Graves and S. Hamud for their field assistance USDA Forest Service Pacific Southwest Research Station, and USDA Forest Service Forest Health Monitoring program for funding The San Bernardino, Angeles, and Cleveland National Forests for permission to use the sites

22 Intrinsic dispersal capacity of the Mediterranean pine engraver, Orthotomicus erosus, an invasive bark beetle Deguang Liu Robert C. Venette Steve Munson Beverly Bulaon Mary L. Flint Steven J. Seybold University of California, Davis USDA Forest Service

23 Exotic because the Mediterranean Pine Engraver (MPE) originates from MPE Mediterranean, Middle East, Central Asia, and China

24 And has invaded MPE Native range Chile, South Africa, Swaziland, and the U.S.

25 Hosts Pines: Monterey, red, ponderosa, lodgepole, sugar, Jeffrey, grey, white, jack, loblolly, Italian stone, Canary Island, Scots, and Aleppo Others: Douglasfir, black spruce, white spruce, tamarack Aleppo pine infested by MPE Lee et al. 2008

26 Distribution in California

27 Attractive semiochemicals Male-infested log c d Ips typographus bait c de MPE bait MB, ( )-ipsd., rac. α-pinene 2X a c de a MB, ( )-ipsd., rac. α-pinene 1X MB, ( )-ipsd., ( )-α-pinene b* ab b* ab MB, ( )-ipsd., (+)-α-pinene b ab MB, ( )-ipsdienol c c unbaited Male c e Female Lee et al MPE per week + SE

28 Dispersal model derived from 1 km radius markrecapture study (Visalia, CA, June 4-19, 2007) 120 Average total capture in 4 days/trap ln( f ( r)) = a + Observed for commercial lure Predicted for commercial lure Observed for improved lure Predicted for improved lure b r Distance (m)

29 Predicted dispersal of MPE based on markrecapture study of 2007 (average for both lures; reflects a more expected case) i Distance (x i, meters) Proportion of beetles moving from 0 to x i Proportion of beetles moving from x i-1 to x i Proportion of beetles moved relative to proportion moved

30 Large Scale Mark-Recapture Study in km Radius, Tulare Lake, Kettleman City, CA

31 Large scale dispersal study near Kettleman City, CA in 2008

32 It s a lonely world if you re a bark beetle searching for a pine tree..

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35 N = 16 P < 0.05 N = 28 P < Visalia, CA, June 4-19, km radius (3.1 km 2 ) array Commercial bait Improved bait Mean No. / trap / day (±SE) N = 23 P < N = 61 P < N = 136 P < N = 155 P < Commercial 4 6 bait km Tulare Lake, Kettleman City, CA, June 1-18, km radius (314 km 2 ) array Improved bait N = 13 P < N = 14 P < N = 5 P < 0.05 N = 8 P < 0.05 N = 5 P < >=6 km Distance from the release point

36 Trial 2 Release point N E Wind speed: 34.4 km/h Red arrow

37 Summary-2008 Study Approx. 18,000 beetles released over three trials, recapture ranged from 9% to 40% Improved pheromone bait continues to outperform the widely used commercial bait, esp. at low population densities (15 times better) Dispersal is highly influenced by wind Within 24 hours of release, a few beetles (0.2 to 0.7%) dispersed 2-10 km

38 Acknowledgements Funding Support: USDA Pacific Southwest Research Station USDA FS Forest Health Technology Enterprise Team, Fort Collins, CO, "Dispersal Forest Service potential of the Mediterranean pine engraver, Orthotomicus erosus, in support of risk mapping. USDA Forest Service Special Technology Development Program, Improved early detection for the Mediterranean pine engraver, Orthotomicus erosus, an invasive bark beetle (R ). People/Organizations: A.D. Graves and S.M. Hamud for field and lab assistance. Boswell Company, McCarthy Family Farms, and Sandy Ridge Farms for access to their properties.