German Cockroach
Blattella germanica
Anatomy
Identification
Distinguishing Features
- Two distinct dark longitudinal 'racing stripes' (pronotal bands) on the shield behind the head
- Wings present and cover abdomen, but rarely flies—prefers to run
- Long antennae, nearly body length
- Nymphs darker with single tan stripe down back
- Females often seen with egg case (ootheca) protruding from abdomen
Biology
Lifecycle
CRITICAL: Unlike other cockroaches, females carry the ootheca (egg capsule) protruding from their abdomen until ~24 hours before hatching. This maternal care protects eggs from dehydration and pest control treatments—making German Cockroaches significantly harder to eliminate than other species. 30-40 eggs per case, 4-8 cases per lifetime. Nymph to adult in 6-12 weeks.
Diet
Omnivorous scavengers: crumbs, grease, starch, soap, toothpaste, glue. Can survive weeks without food.
Nesting
Thigmotactic (love tight spaces)—prefer cracks no thicker than a credit card. Aggregate in warm, humid harbourages near food and water: refrigerator compressor motors, dishwasher insulation, coffee maker bases, stove clocks, and gaps around plumbing under sinks. The warmth and moisture of appliance motors are ideal.
Signs of Infestation
Live cockroaches at night
Turn on kitchen light at night—roaches scatter to hiding spots.
Pepper-like droppings
Small dark specks in drawer corners, on shelves, behind appliances.
Egg cases (oothecae)
Tan, ridged capsules (8mm) found in protected areas.
Musty odour
Large infestations produce distinctive oily smell from aggregation pheromones.
Where They Nest
- Behind and under refrigerators
- Inside dishwasher and stove motors
- Under sinks around plumbing
- Inside electrical outlet boxes
- Cracks in kitchen cabinets
Distribution in Canada
Strictly an indoor pest—cannot survive Canadian winters outdoors. Found nationwide in heated buildings. Introduced via grocery bags, used appliances, cardboard boxes, and supply chain deliveries. Does NOT migrate between buildings through outdoor routes; infestations spread through shared walls in multi-unit housing or by hitchhiking on goods.
Active Season
Active year-round indoors. Populations can explode rapidly in favourable conditions.
House Types at Risk
This pest is commonly found in these home types
Condo / Apartment
High RiskShared walls and plumbing allow spread between units. Infestations can become building-wide.
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Townhouse
High RiskParty walls and shared infrastructure enable movement between attached units.
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Bi-Level
Moderate RiskKitchen appliances and bathroom fixtures provide ideal warm, humid harbourage near food.
View house details →Prevention
- Clean up food debris immediately, especially grease
- Store food in sealed containers
- Fix plumbing leaks promptly
- Seal cracks around pipes and outlets
- Inspect groceries and boxes before bringing indoors
Professional Treatment
Gel baits are primary treatment—placed in cracks where cockroaches harbour. IGR (insect growth regulators) prevent reproduction. Multi-visit programs needed for heavy infestations.
See services we offerInsight Pest Solutions Canada does not currently treat cockroaches.
Frequently Asked Questions
What does a German Cockroach eat?
Omnivorous scavengers: crumbs, grease, starch, soap, toothpaste, glue. Can survive weeks without food.
Where does a German Cockroach nest?
Thigmotactic (love tight spaces)—prefer cracks no thicker than a credit card. Aggregate in warm, humid harbourages near food and water: refrigerator compressor motors, dishwasher insulation, coffee maker bases, stove clocks, and gaps around plumbing under sinks. The warmth and moisture of appliance motors are ideal.
When is a German Cockroach most active?
Active year-round indoors. Populations can explode rapidly in favourable conditions.
What are the signs of a German Cockroach infestation?
Live cockroaches at night: Turn on kitchen light at night—roaches scatter to hiding spots. Pepper-like droppings: Small dark specks in drawer corners, on shelves, behind appliances. Egg cases (oothecae): Tan, ridged capsules (8mm) found in protected areas. Musty odour: Large infestations produce distinctive oily smell from aggregation pheromones.
How can I prevent a German Cockroach infestation?
Clean up food debris immediately, especially grease. Store food in sealed containers. Fix plumbing leaks promptly. Seal cracks around pipes and outlets. Inspect groceries and boxes before bringing indoors.
How is a German Cockroach treated?
Gel baits are primary treatment—placed in cracks where cockroaches harbour. IGR (insect growth regulators) prevent reproduction. Multi-visit programs needed for heavy infestations.
Scientific Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Blattodea
- Family
- Ectobiidae
- Genus
- Blattella