The Red Imported Fire Ant in California

1. The Red Imported Fire Ant in California Dr. Les Greenberg University of California, Riverside

2. Origin of Imported Fire Ants • South America: Brazil, Uruguay, Paraguay, Argentina

3. U.S. Introduction • Introduction to Mobile, Alabama, between 1930-1940 • Probably arrived in ship ballast • From there, spread outward to the Southeast and West

4. Fire ant quarantine

6. Potential spread of fire ants • Originally 10° F. isothermal line; now at 0° F. • Limiting factor of moisture • Adaptation to man-made environment

7. U. S. Expansion

10. Mating

11. Fire Ant Dispersal

12. Stinging and Pustule Formation

13. Transformers Shorted

14. Infested Areas of Southern California

15. Locating Infestations • Visual inspection • Luncheon meat • Corn chips

16. Nurseries in Trabuco Canyon

17. Subterranean Trail Under Plastic

18. Flower beds in Los Alamitos

19. Coachella Valley Golf Courses

20. Mounds on Mowed Grass

21. Mound at Sprinkler

22. Exit holes from underground foraging trails on putting green

23. Cleveland National Forest

24. 2500 ft

25. WetlandsRancho Santa Margarita

26. Infested Areas of the Central Valley

27. Almond Groves in Central Valley

30. Biological Control Agents • Phorid flies: decapitating flies • Protozoan parasites: Thelohania • Other species of ants

31. Phorid Flies

32. Phorid Flies (Decapitating Flies)

33. Phorid Flies

34. Phorid Fly Release

35. Phorid Fly Releases

36. Phorid Fly Releases • Between 1996 and 2002 the decapitating fly, Pseudacteon tricuspis, was released at 56 sites in the southeastern United States • Most releases have been made by the USDA-ARS, CMAVE, Gainesville, FL ( 32 sites) and the University of Texas, Austin (15 sites).

37. Phorid Fly Releases • Overwintering populations of flies were successfully established at 19 sites in 6 states (AL-3, FL- 5, LA-3, MS-1, SC-2, TX-5).

38. Phorid Fly Expansion in Florida

39. Thelohania solenopsae, a microsporidian intracellular parasite • The most common fire ant pathogen in Brazil • It was discovered in the US in 1998 (FL, TX, MS, OK). • Decreases ant’s longevity and reduces colony size

40. Inoculating Mound with Thelohania

41. Insecticide Runoff from Treated Houses

42. Treatments 2007 • Treatments used • 3 gals fipronil spray perimeter • 1 gal fipronil spot • 3 gals bifenthrin spray • Combination of fipronil spray and bifenthrin granules • Bait stations with imidacloprid

43. Data From a Typical House • Lawn area measured • Water meter recorded • Runoff estimated • Sprinkler locations mapped • Collection site noted • Time that irrigation is on

44. Water collection dam

45. Dam placement at curb • 4-in styrofoam cut into U-shape • Sand bags on styrofoam • Styrofoam and sand bags put inside disposable plastic bags

46. Sample collection

47. 60-ml aquatic pipette

48. Volumetric flow rate (Q), the volume of fluid which passes through a given volume per unit time • Q = A x v, where • A = area (depth and width of water stream) • v = uniform average velocity of water (how long it takes to flow a known distance) • Q*time - gives us an estimate of total water runoff

49. Sample processing • One liter sample collected from one bank of sprinklers per house • Sample stored at 40C • Sample analyzed at laboratory of Dr. Jay Gan in environmental sciences, UC Riverside

50. Schedule 2007 • Pretreatment ant evaluations and water samples collected in June • Post-treatment ant evaluations done at 1,2,4,and 8 weeks • Post-treatment water samples collected at 1, 4, and 8 weeks