Cockroaches and Their Cockroaches and Their ControlControl

Dr. Richard M. Houseman

Department of Entomology

University of Missouri

Cockroaches

• Order Blattaria– 3,500 species worldwide– 55 species in U.S.

• Incomplete metamorphosis• Food Scavengers

– Preferences vary by species

• Warm, moist habitats– Domestic/peridomestic

• High reproductive capacity– Oviparous, ovoviviparous,

viviparous

Life History• Life Stages

– Eggs• Normally produced in egg cases called ootheca• Hatch within 30-60 days, depending on species• Some species lay no eggs, or they hatch internally

– Nymphs• Most active feeding stage for molting and growth• Live for 30-350 days, depending on species

– Adults• Intermittent feeding and reproduction• Live for 2-52 weeks, depending on species

Cockroach Biology

• Habitats– Active at night– Prefer warm, moist environments

• Near food and water sources• Protected harborages are very important

– Domestic species occur indoors• Peak feeding just after dark and just before dawn

– Peridomestic populations not limited to indoors• Peak feeding after dark until middle of night

Cockroach Biology• Feeding and Nutrition

– Cockroaches are not proud…just hungry

– Chewing mouthparts• Feed on a wide variety of

things--starches, greases, sweets, decaying organic matter, feces, garbage, etc.

– Contamination• Regurgitation and defecation

on food• Pheromone secretions

(characteristic odor)

Cockroach Biology

• Reproduction– Chemicals and sound used to attract mates

• Female attracts male

– Antennal contact is essential• Primarily on cuticle and antennae

– Copulation• May last for hours

• Package of sperm deposited

• Males of some species seal vaginal opening

Missouri Cockroaches

• 5 Common Species– German– Brown-banded– American– Oriental– Pennsylvania wood

• Domestic and peridomestic

• Can be identified by the egg case or adult stage

Domestic Cockroaches

• German cockroach(Blatella germanica)

– ½ inch; grayish-tan; two stripes pronotum;

• ootheca slender, 1/3”, light brown

– Ootheca carried for 3weeks• 1 day; 30-40 eggs; 4-8 ootheca

• Nymphs stage lasts 35-60 days

• Adults live 4-6 months

– Variety of foodstuffs

– Mostly kitchens and bathrooms

Domestic Cockroaches• Brown-banded cockroach

(Supella longipalpa)

– ½ inch; red-brown; light stripe across abdomen;

• ootheca small, ~1/4”, barrel-shaped

– Attached ootheca• 40-60 days; 18 eggs; 12-16 ootheca

• Nymph stage 3-5 months

• Adults 4-8 months

– Variety of foodstuffs

– Throughout homes• Appliances, ceilings, walls

Peridomestic Cockroaches• American cockroach

(Periplaneta americana)

– 1½ inch; red-brown; yellow margin of pronotum

• ootheca large, >1/3”, barrel-shaped

– Attached ootheca• 30-50 days; 14 eggs; 16-20 ootheca

• Nymph stage 6-20 months• Adults 12-14 months

– Decaying organic matter– Moist, shady areas outdoors– Drains, basements, boiler

rooms inside

Peridomestic Cockroaches• Oriental cockroach

(Blatta orientalis)

– 1 inch; dark brown; shiny; no distinctive markings

• ootheca large, >1/3”, barrel-shaped

– Attached ootheca• 40-60 days; 16 eggs; 6-8 ootheca

• Nymph stage 6-20 months• Adults 12-14 months

– Decaying organic matter, filth– Moist, shady areas outdoors– Sewers, drains, basements

inside

Peridomestic Cockroaches• Wood cockroaches

(Parcoblatta pennsylvanica)

– 2/3 inch; dark brown; slender; yellow margin on pronotum, wings

• Ootheca slender, curved, >1/3”

– Ootheca deposited under bark

– Rarely breed indoors• Nuisance pests in May, June

– Decaying organic matter

– Incidental invaders• Infested firewood often the cause

Cockroach Control

• Cultural– Sanitation is key

• Chemical (>200 products)– Baits

• Most important part of roach control• Should be placed near harborage

– Nymphs most susceptible– Adult females less susceptible

• Don’t place in treated areas• Can be transmitted via feces

Cockroach Control

• Chemical– Liquids

• Crack and crevice spray– Directed at harborage

– Helpful to get females

– Quick knockdown

• Space sprays– Gives some residual activity

– Shouldn’t use this during baiting program