For residents of Edmonton, it's a tie between the German cockroach and the American cockroach. Because of their small size, German cockroaches can fit into cracks and crevices in your home to live and breed, while American cockroaches are known for their ability to fly. Both of these species can cause serious health concerns with their droppings and the bacteria they leave behind. That's why it's important to call a professional pest control company if you're dealing with an infestation.