These speedy buggers are evasive, and can outnumber any opponent overnight.
In the 1970s, pest management professionals (PMPs) were 10 times more likely to battle nasty German cockroach infestations than American cockroaches.
In many cases, the German cockroaches were taking over commercial and residential accounts. Sure, we’d run into the Americans from time to time, but not nearly as often or as great numbers as the Germans we battled far more frequently. Forty years later, not much has changed.
A quick look at typical glue-board catches demonstrates the head-spinning difference in population dynamics between German and American cockroaches. The accompanying Photo 1 shows a sticky trap laden with German cockroaches less than 24 hours after being placed in a kitchen cabinet. Photo 2 shows a typical, mostly empty, sticky trap at an American cockroach-infested account.
Even though a picture is worth 1,000 words, I’ll continue to explain because Photos 1 and 2 drive home just one of my 13 face-off supporting points (No. 13 — unmatched reproductive capacity).
Following are 13 Reasons the German Cockroach is King of the Ring:
- Diminutive size. The American cockroach is bigger and stronger, but this is more of a liability than an asset. Weighing in at a fraction of its opponent, the German cockroach is more nimble. The German’s smaller size also allows it to hide in the smallest places and take advantage of harborages where the American won’t fit.
- Easily transported. Once again, the German cockroach’s smaller size is an advantage. The German is transported more easily as an unseen hitchhiker from infested locations.
- Easily hidden. Because of its small size and enviable mobility, the German cockroach can hide easily in areas that are difficult to find and treat. These areas harbor reservoirs of Germans, leading to long-term infestations.
- Crypto-Biotic. The German cockroach tends to remain hidden as it conducts regular activities. By the time a PMP sees one German, he might find he’s already late to the party.
- Versatile eater. The German cockroach is capable of feeding on almost any food it finds. In the absence of food, the German also can survive on nonfood items, such as glue and other materials in infested locations.
- Bait acceptance and aversion. The German cockroach has two sets of palpi to taste food prior to ingestion. These palpi must be fooled before the German will accept the bait and ingest it. Germans also commonly duck away from some bait matrices.
- Witness protection program. Gravid German cockroach females tend to move around structures less and usually remain hidden in harborage areas, which reduces their chance of being discovered and prevents exposure to control technologies and techniques.
- Mobile Moms. A German cockroach mom is much more caring of its developing young than an American cockroach mom. Rather than simply deposit or glue egg cases to a surface, abandoning her young as an American cockroach does, the more-nurturing German cockroach carries her ootheca, which protrudes from the tip of her abdomen. Each egg case protects the German’s developing young, keeping them safe from contact with treated surfaces and predators.
- Sticky pads. The German cockroach has sticky pads that allow it to climb smooth and slick surfaces. The German easily navigates food preparation surfaces, including stainless steel and glass.
- Strength in numbers. Aggregation pheromones, deposited and sensed with rare skill by German cockroaches, allow newly introduced cockroaches to locate harborages and family quickly, providing shelter and the strength of numbers.
- High-capacity egg cases. Some German cockroach egg cases contain 50 or more developing nymphs.
- Time flies. Rapid development from egg to reproductive adult doubles the already-unmatched punch of the German cockroach.
- Champion reproductive capacity. Finally, for the KO, one female German cockroach can have 400,000 descendants in one year. That’s about 500 times the number of descendants a female American cockroach typically spawns in the same time.
You can reach Bello at email@example.com or 770-500-0460.