The Red Imported Fire Ant in The Red Imported Fire Ant in CaliforniaCalifornia

Dr. Les GreenbergDr. Les Greenberg

University of California, RiversideUniversity of California, Riverside

Origin of Imported Fire AntsOrigin of Imported Fire Ants

South AmericaSouth America: : Brazil, Uruguay, Brazil, Uruguay, Paraguay, ArgentinaParaguay, Argentina

U.S. IntroductionU.S. Introduction

Introduction to Mobile, Introduction to Mobile, Alabama, between Alabama, between 1930-19401930-1940

Probably arrived in Probably arrived in ship ballastship ballast

From there, spread From there, spread outward to the outward to the Southeast and WestSoutheast and West

Fire ant quarantineFire ant quarantine

Potential spread of fire antsPotential spread of fire ants

Originally 10° F. isothermal line; now at 0° Originally 10° F. isothermal line; now at 0° F.F.

Limiting factor of moistureLimiting factor of moisture Adaptation to man-made environmentAdaptation to man-made environment

U. S. ExpansionU. S. Expansion

MatingMating

Fire Ant DispersalFire Ant Dispersal

Stinging and Pustule FormationStinging and Pustule Formation

Transformers ShortedTransformers Shorted

Infested Areas of Southern Infested Areas of Southern CaliforniaCalifornia

Locating InfestationsLocating Infestations

Visual inspectionVisual inspection Luncheon meatLuncheon meat Corn chipsCorn chips

Nurseries in Trabuco CanyonNurseries in Trabuco Canyon

Subterranean Trail Under Subterranean Trail Under PlasticPlastic

Flower beds in Los AlamitosFlower beds in Los Alamitos

Coachella Valley Golf CoursesCoachella Valley Golf Courses

Mounds on Mowed GrassMounds on Mowed Grass

Mound at Mound at SprinklerSprinkler

Exit holes from Exit holes from underground underground foraging trails on foraging trails on putting greenputting green

Cleveland National ForestCleveland National Forest

2500 ft2500 ft

WetlandsWetlandsRancho Santa MargaritaRancho Santa Margarita

Infested Areas of the Central Infested Areas of the Central ValleyValley

Almond Groves in Central Almond Groves in Central ValleyValley

Biological Control AgentsBiological Control Agents

– Phorid flies: decapitating fliesPhorid flies: decapitating flies– Protozoan parasites: Protozoan parasites: ThelohaniaThelohania– Other species of antsOther species of ants

Phorid Phorid FliesFlies

Phorid Flies (Decapitating Flies)Phorid Flies (Decapitating Flies)

Phorid FliesPhorid Flies

Phorid Fly ReleasePhorid Fly Release

Phorid Fly ReleasesPhorid Fly Releases

Phorid Fly ReleasesPhorid Fly Releases

Between 1996 and 2002 the decapitating Between 1996 and 2002 the decapitating fly, fly, Pseudacteon tricuspisPseudacteon tricuspis, was released at , was released at 56 sites in the southeastern United States56 sites in the southeastern United States

Most releases have been made by the Most releases have been made by the USDA-ARS, CMAVE, Gainesville, FL ( 32 USDA-ARS, CMAVE, Gainesville, FL ( 32 sites) and the University of Texas, Austin sites) and the University of Texas, Austin (15 sites). (15 sites).

Phorid Fly ReleasesPhorid Fly Releases

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

Phorid Fly Expansion in Phorid Fly Expansion in FloridaFlorida

2002 est.

2001

2000

1999

2002 est.

2001

2000

1999

Thelohania solenopsaeThelohania solenopsae, , a microsporidian a microsporidian intracellular parasiteintracellular parasite

The most common fire The most common fire ant pathogen in Brazilant pathogen in Brazil

It was discovered in the It was discovered in the US in 1998 (FL, TX, MS, US in 1998 (FL, TX, MS, OK). OK).

Decreases ant’s Decreases ant’s longevity and reduces longevity and reduces colony sizecolony size

Inoculating Mound with Inoculating Mound with ThelohaniaThelohania

Insecticide Runoff from Insecticide Runoff from Treated HousesTreated Houses

Treatments 2007Treatments 2007

Treatments usedTreatments used– 3 gals fipronil spray perimeter3 gals fipronil spray perimeter– 1 gal fipronil spot 1 gal fipronil spot – 3 gals bifenthrin spray3 gals bifenthrin spray– Combination of fipronil spray and bifenthrin Combination of fipronil spray and bifenthrin

granulesgranules– Bait stations with imidaclopridBait stations with imidacloprid

Data From a Typical HouseData From a Typical House

Lawn area Lawn area measuredmeasured

Water meter Water meter recordedrecorded

Runoff Runoff estimatedestimated

Sprinkler Sprinkler locations locations mappedmapped

Collection site Collection site notednoted

Time that Time that irrigation is onirrigation is on

Water collection damWater collection dam

Dam placement at curbDam placement at curb

4-in styrofoam cut into 4-in styrofoam cut into U-shapeU-shape

Sand bags on Sand bags on styrofoamstyrofoam

Styrofoam and sand Styrofoam and sand bags put inside bags put inside disposable plastic disposable plastic bagsbags

Sample collectionSample collection

60-ml aquatic pipette60-ml aquatic pipette

Volumetric flow rate Volumetric flow rate (Q(Q)),, the volume the volume of fluid which passes through a given of fluid which passes through a given

volume per unit timevolume per unit time

Q = A x v,Q = A x v, where where– A = area (depth and width of water stream)A = area (depth and width of water stream)– vv = uniform average velocity of water (how long = uniform average velocity of water (how long

it takes to flow a known distance)it takes to flow a known distance)

Q*time - gives us an estimate of total water Q*time - gives us an estimate of total water runoffrunoff

Sample processingSample processing

One liter sample collected from one bank of One liter sample collected from one bank of sprinklers per housesprinklers per house

Sample stored at 4Sample stored at 400C C Sample analyzed at laboratory of Dr. Jay Sample analyzed at laboratory of Dr. Jay

Gan in environmental sciences, UC Gan in environmental sciences, UC RiversideRiverside

Schedule 2007Schedule 2007

Pretreatment ant evaluations and water Pretreatment ant evaluations and water samples collected in Junesamples collected in June

Post-treatment ant evaluations done at Post-treatment ant evaluations done at 1,2,4,and 8 weeks1,2,4,and 8 weeks

Post-treatment water samples collected at 1, Post-treatment water samples collected at 1, 4, and 8 weeks4, and 8 weeks

fipronil desulfinyl

sulfide

Concentration of fipronil and its byproducts in runoff

sulfone

PRETREAT

WEEK1

WEEK4

WEEK8

Trial

4000

8000

12000

16000

ng/l

FIP_3GALFIP_1GAL

TREATMENT

PRETREAT

WEEK1

WEEK4

WEEK8

Trial

10000

20000

30000

40000

50000

ng/l

FIP_3GALFIP_1GAL

TREATMENT

PRETREAT

WEEK1

WEEK4

WEEK8

Trial

500

1000

1500

20002500300035004000

ng/l

FIP_3GALFIP_1GAL

TREATMENT

PRETREAT

WEEK1

WEEK4

WEEK8

Trial

4000

8000

12000

16000

20000

ng

/l

FIP_3GALFIP_1GAL

TREATMENT

Concentrations of fipronil and bifenthrin in runoffWith Ceriodaphnia LD50s

PRETREAT

WEEK1

WEEK4

WEEK8

Trial

10000

20000

30000

40000

ng

/ l

FIP_3GALFIP_1GALBIFEN_SPRAYBIFEN_GRAN

TREATMENT

Fipronil LD50

Bifenthrin LD50

20082008

6 different pesticide treatments6 different pesticide treatments– 3 houses sampled per treatment for insecticide 3 houses sampled per treatment for insecticide

runoff = 18 houses sampled runoff = 18 houses sampled – Sample periodsSample periods

PretreatmentPretreatment 1 day1 day 1 week1 week 2 week driveway flush2 week driveway flush

This summer’s fipronil treatments This summer’s fipronil treatments

All fipronil treatments limited to 1 galAll fipronil treatments limited to 1 gal– 1 gal peripheral spray -- pin stream nozzle 1 gal peripheral spray -- pin stream nozzle – Spot treatments Spot treatments – Same as above but not within 15 ft of street and Same as above but not within 15 ft of street and

5 ft of sidewalks5 ft of sidewalks

This summer’s bifenthrin treatmentsThis summer’s bifenthrin treatments

All use 3 galsAll use 3 gals– Pin stream nozzle perimeter treatment Pin stream nozzle perimeter treatment – Traditional fan nozzle perimeter applicationTraditional fan nozzle perimeter application– Spot treatments with 3 gals, but not within 15 ft Spot treatments with 3 gals, but not within 15 ft

of street or 5 ft of sidewalksof street or 5 ft of sidewalks

ConclusionsConclusions

We can successfully monitor how much We can successfully monitor how much insecticide runs off from treated houses due insecticide runs off from treated houses due to irrigationto irrigation

We can test different application techniques We can test different application techniques to minimize insecticide runoffto minimize insecticide runoff