Source: UNIVERSITY OF FLORIDA submitted to
Sponsoring Institution
State Agricultural Experiment Station
Project Status
Funding Source
Reporting Frequency
Accession No.
Grant No.
Project No.
Proposal No.
Multistate No.
Program Code
Project Start Date
Dec 8, 2000
Project End Date
Nov 30, 2005
Grant Year
Project Director
Koehler, P. G.
Recipient Organization
Performing Department
Non Technical Summary
Subterranean termites are the most important structural pests. Severe allergy to cockroaches is common in the general population by contact, ingesting their excrement or inhaling cockroach fragments. This project is intended to discover and evaluate new and safer management and control technologies that will alleviate the damage caused by cockroaches, termites, and other household pests. It will evaluate new technologies for delivering educational programs to the pest control industry. This project will develop and test new educational approaches for the pest control industry.
Animal Health Component
Research Effort Categories

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
Knowledge Area
721 - Insects and Other Pests Affecting Humans;

Subject Of Investigation
3110 - Insects;

Field Of Science
1130 - Entomology and acarology;
Goals / Objectives
1. Elucidate basic behavioral patterns of urban pests especially cockroaches in relation to disease transmission and as causative agents of asthma. 2. Develop and evaluate new technologies for the control of cockroaches and ants. 3. Determine the behavior of termites in relation to soil conditions close to structures and residual soil termiticides. 4. Develop and evaluate new educational technologies for the pest control industry.
Project Methods
Elucidate basic behavioral patterns of urban pests with laboratory studies by the evaluation of various markers such as dyes, chemicals, and genetic markers. Perform Field studies of the movement within and between structures. Document age structure, mobility, foraging patterns, and spatial patterns of harboring cockroaches. Document foraging patterns of termites and determine influence of termiticides on that behavior. Evaluate the attractiveness of cockroach bait ingredients and evaluate the trail following behavior in German cockroaches. Perform biological control of cockroaches by collection of naturally occurring parasites in Florida, establishing laboratory colonies and eventually field evaluations and release. Evaluate methods of pest monitoring, determine methods of preserving field termite monitors from fungal decay, and evaluate influence of fungi on termite feeding. Develop and evaluate new technologies for the control of cockroaches and ants. Evaluate various experimental spray compounds and formulations in the laboratory and field for control of cockroaches, termites and ants. Evaluate new experimental bait compounds for activity in the laboratory and field for control of cockroaches and ants. Evaluate mechanisms of resistance in multi-resistance in multi-resistant laboratory strains of German cockroaches, survey the extent of German cockroach resistance in the southeastern US, evaluate new formulations of pesticides against resistant strain, and develop methods of analyzing the degrees of resistance with individual cockroaches using esterase and oxidase analysis. Develop and evaluate new technologies for the control of ants, investigate foraging behavior of various ant species and develop toxic baits for control of various species. Develop and evaluate new technologies for the control of stored food pests, silverfish, and other crawling and flying insects. Determine the behavior of termites in relation to soil conditions close to structures and residual soil termiticides. Develop and evaluate new educational technologies for the pest control industry.

Progress 12/08/00 to 11/30/05

Termites are difficult to detect in structures. Dogs were able to differentiate termites from other insects. Properly trained and handled dogs were 96% accurate in finding termites with a 4% false indication rate. As a result, canines have been commercialized as a termite detection service. Subterranean termites usually enter buildings by tunneling from their colonies in the soil. Subterranean termite tunneling behavior in soil was determined to be affected by the number of termites in a colony and by soil compaction, with reduced tunneling in compacted soil. Tunneling is energy expensive for termites so once a tunnel is established they only do minor modifications to it. Therefore, a termite tunnel network would be more extensive in disturbed soil, especially in areas around buildings and underground utilities. A common way to control subterranean termites is to apply a residual soil treatment underneath and around houses. Soil around houses with brick veneer had high soil pH due to the mixture of spilled cement in the soil. Residual soil termite treatments degraded in high soil pH caused by spilled cement. Another common subterranean termite control treatment technique is termite bait placed in stations in the ground. Diflubenzuron bait was evaluated for its potential as a termite bait, and was shown to protect houses from termite infestation. The product was commericalized and is available to pest controllers. A survey of houses in three Florida counties indicated that home construction practices affect infestation rates of subterranean termites. Placement of landscape shrubs, trees, irrigation, downspouts, and air conditioning condensate lines within 2 feet of the structure was found to increase the rate of termite infestations in houses. As a result of the survey, Florida building codes were modified with termite protection code language to solve the problems with termite foraging guidelines from plants roots and sources of water for termites. Cockroaches are important pests in structures. Cockroaches were found to follow fecal trails from harborages to food and water. Fecal extracts were shown to enhance sprays for cockroach control, and location of trails in buildings allows pest controllers to place baits close to cockroach activity. The new bait active ingredients, indoxacarb and emamectin benzoate were evaluated for control of bait averse German cockroaches. Indoxacarb is now registered and available to pest controllers and emamectin benzoate is being commercialized. The interaction of enteric bacteria with the cuticle of American cockroaches and pharaoh ants was investigated. Salmonella and E. coli O157-H7 were found to embed in the cuticular waxy layer and remain viable. This indicates that cockroaches and ants can be important transmitters of bacterial food poisoning organisms. Carbon dioxide is often used to immobilize colonized cockroaches for counting into experiments. Carbon dioxide was found to affect bait feeding experiments for up to 48 hours after cockroach recovery. As a result most researchers now have modified cockroach handling techniques to allow cockroaches to adequately recover and behave normally.

The results of this research are being used by pest managers to reduce insecticide usage and manage urban pests. Canine termite detectors were proven capable of reliably detecting termites. By finding termites more efficiently, termiticide use can be targeted to locations where they are entering buildings. Movement of termites and cockroaches is dictated by their response to their environment. Our discoveries about termite tunneling help us understand where termites enter structures and termiticide treatments should be placed. We discovered that cockroaches follow trails from harborage to food and water sources. Until this work was published pest controllers thought that cockroach movement was random, and consequently placed bait and spray treatments throughout the structure. Cockroaches are important urban pests as causative agents of asthma. Human pathogens, Salmonella and E. coli O157:H7, were found on the exterior cuticle of cockroaches and ants for days after the bacteria were applied. We found the waxy layer of cockroaches is very liquid and mobile, allowing the flagellated bacterial cells to swim through the waxy layer and attach to the cuticle. New insecticides for pest control were evaluated for commercial development. A new termite bait containing diflubenzuron was found to protect houses from subterranean termites. New German cockroach baits containing indoxacarb or emamectin benzoate were evaluated for control of bait averse cockroaches. Both indoxacarb and emamectin benzoate baits overcame bait aversion and were effective in controlling German cockroaches


  • Richman, D.L., C.L Tucker, and P.G. Koehler. 2006. Influence of Portland cement amendment on soil pH and residual soil termiticide performance. Pest Management Sci. 62(2006): 1216-1223.
  • Branscome, D. 2004. Interactions of enteric bacteria with american cockroaches (periplaneta americana) and pharaoh ants. PhD dissertation, University of Florida, Gainesville, FL.

Progress 10/01/04 to 09/30/05

New bait containing diflubenzuron products were evaluated for control of subterrantean termites in field situations. These tests are ongoing and will continue for several years. Neonictotinoid termiticides and combinations with pyrethroids were evaluated for activity against subterranean termites. Residual treatments for pest ant control were evaluated. Fipronil was found to kill queens and was an effective insecticide for residual ant control. Two new cockroach bait products were evaluated. Emamectin and indoxacarb were found to be effective new products for control of bait aversive and insecticide resistant cockroaches. New products were evaluated for fly control. Attractants for fly traps were evaluated, and residual fly insecticides were tested for activity against house flies.

New products for control of household pests will allow pest management professionals and homeowners to effectively and safely manage pest infestations. These new methods will assist the public to control cockroaches, ants, termites, and flies.


  • Influence of carbon dioxide gas on German cockroach (Dictyoptera: Blattellidae) knockdown, recovery, movement and feeding. Branscome, D.D.; Koehler, P.G.; Oi, F.M., Physiological entomology., vol. 30, no. 2, pp. 144-150, June 2005
  • Tunnel formation by different numbers of eastern subterranean termites (Isoptera: Rhinotermitidae) in laboratory arenas. Tucker, C.L.; Koehler, P.G.; Oi, F.M., Sociobiology., vol. 45, no. 3, pp. 731-744, 2005
  • Influence of soil compaction on tunnel network construction by the Eastern Subterranean termite (Isoptera: Rhinotermitidae). Tucker, C.L.; Koehler, P.G.; Oi, F.M., Journal of economic entomology., vol. 97, no. 1, pp. 89-94, Feb 2004

Progress 10/01/01 to 10/01/02

Dogs were trained to detect eastern subterranean termites (EST) using the United States Customs method of scent detection dog training modified with a food reward. Dogs were tested with various numbers and species of termites placed in vented PVC containers. Trained dogs were 95.93% accurate in finding >40 EST workers and incorrectly indicated the presence of termites in 2.69% of the containers without termites. Dogs trained to locate EST were also 100% accurate in finding R. virginicus, 98.89% accurate in finding C. formosanus, 97.33% accurate in finding C. cavifrons, and 88.89% accurate in finding I. snyderi. Dogs were able to discriminate live termites from non-termite material. Trained dogs' false response rate was 25.33% to EST damaged wood, 6.67% to American cockroaches, and 2.67% to carpenter ants. Tunneling of various numbers of EST was investigated in sand of various compaction levels was investigated. Tunneling was significantly fastest in low compaction soil and at high termite densities. Minimum diameters of tunnels allowed 2 termites to pass. Tunnels were in a geometric pattern and angles between primary and secondary tunnels remained constant for all termite densities and soil compaction levels. Termite survival was lowest for low termite densities and high soil compaction. The amount of wood moisture necessary for EST survival was determined by placing termites in wood blocks of 20-30% wood moisture. At 20% wood moisture the LT-90 was 12.6 days, but was 105 days at 30% wood moisture. Wood moisture above 25% was sufficient to allow termites to survive for extended periods of time. To determine typical wood moisture content of EST-infested wood located in termite stations, moisture content was determined with a 2-prong moisture meter. The mean moisture content of infested wood was 53% and was significantly higher than the content of non-infested wood (44%). Carbon dioxide anesthesia is used to knock down cockroaches before many laboratory experiments. Susceptibility of 4 cockroach strains to CO-2 anesthesia was determined. Cockroaches were knocked down in 7-45 sec; presumptive recovery occurred in 398-587 s. Although presumptively recovered from knockdown, cockroaches exited harborages to forage for food more slowly than for compressed air controls. In addition, food consumption was less, and, consequently, bait consumption was also reduced. As a result, Co-2 exposed cockroaches died significantly more slowly after consuming baits than control cockroaches.

For the first time, dogs as termite detectors have been scientifically proven to be capable of accurately detecting hidden termite infestations in buildings. The training and handling method was shown to be very important. As a result, trainers and handlers are now forming a canine termite detection association with high standards of performance, similar to police dog standards. The knowledge of termite tunnel construction will allow better placement of termite baits around structures to obtain control. Because termites prefer tunneling in soil of low compaction, it may be possible to aerate soil around bait stations to encourage termite activity around control devices. Termite survival in wood of various moisture contents allows inspectors after treatment to determine whether termite survival in wood is due to faulty treatments or whether more time is needed to kill the termites. The knowledge that termites will die with 2 weeks in wood moisture of less than 20% will enhance inspections. Also the knowledge that termites will survive for more than 6 months in wood of 30% will prevent retreatments with expensive termiticides. Cockroach researchers need to be aware that cockroach recovery from carbon dioxide anesthesia may take long periods of time and may affect experimental results. Cockroaches presumably recover from anesthesia within minutes. But foraging and feeding behavior of cockroaches can be suppressed for many hours.


  • Tucker, C. L. 2002. Construction of tunnel network components by subterranean termites, Reticulitermes flavipes (Kollar), in soils of various compaction levels. M.S. Thesis. University of Florida, Gainesville, FL. 112 pp.
  • Brooks, S. E. 2001. Canine termite detection. M.S. Thesis. University of Florida, Gainesville, FL. 66 pp.
  • McManamy, K. D. 2002. The effect of biotic and abiotic factors on the survivorship of the eastern subterranean termite, Reticulitermes flavipes (Kollar). M.S. Thesis. University of Florida, Gainesville, FL. 68 pp.

Progress 10/01/00 to 10/01/01

German cockroaches live in structures and forage for food and water. by following chemical trails. German cockroaches exhibited trail-following behavior by following chemicals in cockroach feces. Trail-following accuracy varied among the cockroach groups. The mean distance from the fecal trail ranged from 18.45 to 110.05 cm with adult males less than or equal to adult females less than or equal to late instars < gravid females. Fecal trails are not thought to be actively deposited. Rather, the passive distribution of fecal material within the home range results in the accumulation of trails along frequently traveled routes (i.e., between resources and the cockroach harborage). The efficacy of chlorpyrifos and boric acid formulations was tested with and without the addition of fecal extracts. The addition of the aqueous extract produced significantly greater cockroach mortality. Termiticides are applied to soils under houses to protect them from subterranean termites. The ability of eastern subterranean termites to penetrate various concentrations and treatment thicknesses ranging from 1.0 to 50.0 mm of Dursban TC and Premise 75 was evaluated in a laboratory bioassay. Termites penetrated only a few millimeters into 500 ppm Dursban TC-treated soil at all thicknesses and died as a result of contact. Termites were found to be able to detoxify insecticides. Three alpha-naphthyl acetate hydrolyzing esterase isozymes were purified from microsomes prepared from Reticulitermes flavipes workers.

Cockroaches and termites are very difficult to control in infested structures. The discovery of trail following in German cockroaches will improve the efficacy of insecticides, reduce the amounts needed to control infestations, and allow targeting of applications to surfaces cockroaches frequently travel. Some soil termiticides repel termites rather than kill them. Imidacloprid and fipronil were found to be non-repellent and killed termites rather than repelling them. This information is critical for understanding the mode of action of these commonly used termiticides. Also, the discomvery of hydrolizing enzymes in termites was the first discovery of detoxification systems in termites.


  • GAHLHOFF, J.E. Jr. and P.G. KOEHLER. 2001. Penetration of the eastern subterranean termite into soil treated at various thicknesses and concentrations of Dursban TC and Premise 75. J. Econ. Entomol. 94: 486-491.
  • MILLER, D.M. and P.G. KOEHLER. 2000. Trail-following behavior in the German cockroach (Dictyoptera: Blattellidae). J. Econ. Entomol. 93: 1241-1246.
  • STRONG, C.A., VALLES, S.M., KOEHLER, P.G., BRENNER, R.J. 2000. Residual efficacy of blatticides applied to surfaces contaminated with German cockroach (Dictyoptera: Blattellidae) feces. Fla. Entomol. 83: 438-445.
  • MILLER, D.M., KOEHLER, P.G., NATION, J.L. 2000. Use of fecal extract trails to enhance trap catch in German cockroach (Dictyoptera: Blattellidae) monitoring stations. J. Econ. Entomol. 93: 865-870.
  • MILLER, D.M. and P.G. KOEHLER. 2000. Novel extraction of German cockroach (Dictyoptera: Blattellidae) fecal pellets enhances efficacy of spray formulation insecticides. J. Econ. Entomol. 93: 107-111.
  • VALLES, S.M., OI, F.M., and STRONG, C.A. 2001. Purification and characterization of trans-permethrin metabolizing microsomal esterases from workers of the eastern subterranean termite, Reticulitermes flavipes (Kollar). Insect Biochem. & Molec. Biol. 31: 715-725.