A large number of cockroach species can be found in California, many of which are common pests of homes. The most common cockroach pests in the state include German, American, Oriental, brown-banded and Turkestan cockroaches. All of these species ultimately originated from countries overseas, as one can guess by their names, which do not accurately reflect their true geographic origins.
The German cockroach is easily the most commonly encountered and the most commonly managed cockroach pest in California, which is not surprising considering this species has evolved to thrive in human environments and naturally dwells within structures. The brown-banded cockroach is the only other cockroach species in the US that dwells primarily indoors, and while this cockroach pest is commonly found in homes all over the country, their population numbers are decreasing, possibly due to this species’ intolerance of lower temperatures within air-conditioned homes.
German cockroaches are light brown or tan in color and adults are generally between ¼ and ⅝ of an inch in length. The German cockroach is sometimes mistaken for similar looking cockroach species, but the German cockroach can be identified by the characteristic dark double stripes running vertically down their back. Adult brown-banded cockroaches are around ½ inch in length, light brown in color, and they have fully developed wings. This cockroach species gets its name from the two or three light stripes running horizontally across their back.
German cockroaches are usually found in dark and moist harborages on the ground level or basements of homes, and they tend to be most abundant in certain bathroom and kitchen areas, such as beneath appliances, within wall voids, within voids beneath cabinets, and below sinks. While German cockroaches are associated with food preparation areas and stored foods, brown banded cockroaches disperse to all levels within structures, and they are largely indifferent to human food sources. These cockroaches are unique for preferring temperatures at or slightly above 80 degrees, which is ten degrees warmer than the temperature preferred by German cockroaches. Due to their preference for hot conditions, brown-banded cockroaches frequently nest within electronic devices like TVs, and appliances. Unlike German cockroaches, brown banded cockroaches prefer to establish harborages on walls toward ceilings, and they are commonly found behind framed wall decorations, on shelves and inside of furniture voids. Female German cockroaches carry their egg case up until hatching, but female brown-banded cockroaches stick their egg cases beneath tables, under chairs, kitchen cabinets and other protected areas several weeks before hatching. Brown banded cockroaches usually fly when they become disturbed, which makes them easy to identify.
Have you ever found brown-banded cockroaches within your home?