I received a call from my older daughter. She'd moved into an old house in Florida and was having a bug problem. After getting her to describe the pests, I had to tell her the bad news. She had German cockroaches and there was little she could do to completely rid the place of the creatures. But that didn't mean that she couldn't do a few things to ameliorate their impact.
The problem with German cockroaches is that they never go outside. The big brown roaches prefer to live outside and come into your house only when pressured to do so. Oriental cockroaches would also rather be outside. The Asian cockroach, which looks remarkably like the German, can't survive in your house and will come in only when it's attracted to lights.
For most arthropods, the modern man-made caves we live in are just too harsh an environment for them. But not German roaches.
There are more than 4,000 species of roaches around the world, and they've remained in the same general form for over 300 million years. Why change what works? Roaches can fly short distances but prefer to run when they suspect trouble. Most roaches like heat - the hotter the better. They seem to thrive in at 30C or higher, but they must have access to water.
Roaches will eat anything organic, but the German roach has a preference for the foods humans like. If there's no human (or pet) food lying about, German roaches will make do with hair, glue, candle wax, soap or each other. If no food is available, a cockroach can hang around for up to a month waiting for you to get messy.