Cockroaches are one of the most common of all insects and have been for more than 300 million years, as evidenced by fossil remains. All cockroaches are nocturnal, making it easy for populations to build to huge numbers before their presence is realized.
Of the approximately 50 cockroach species that occur in the U.S., the German and American cockroaches are two of the most common species that infest homes, restaurants, hotels and other establishments. Other common cockroaches include the Brown Banded and Oriental, and the recently introduced Asian cockroach.
First found in the U.S. in 1986 in the Lakeland, Florida, area, the Asian cockroach has become a significant pest in the areas it infests, primarily the southeastern states. Similar in looks and size to the German cockroach, the Asian cockroaches' greatest difference and greatest problem for people are that, unlike most other cockroaches, the Asian cockroach can fly.
Its appearance is so similar to the German cockroach that some experts believe it is a strain of that species that developed outdoors in Asia. One of the main differences is that the Asian cockroach's wings are longer and narrower – a physical aspect that most likely enables its flight.
- Scientific Name: Blattella asahinai
- Length: about 5/8 inch long
- Color: Light brown – generally a bit lighter than the German cockroach.
- Unique characteristics: Asian cockroaches prefer to be outdoors and have the ability to fly.
- Feeds on: honeydew, flowers and other plant matter, seeds.
- Found in: single-family, suburban houses and yards, primarily in the grass, mulch, and shaded areas of fallen leaves or other ground covers. They will sometimes infest litter boxes. It is abundant outdoors, where populations of 30,000 to 250,000 per acre have been found.
- Habits and Behavior: Although this cockroach lives primarily outdoors because it is such a strong flier, it also readily enters homes through open doors, windows, and other entry points. They are most active at dusk but will be seen flying during the day.
- Breeding: an egg capsule carries about 40 eggs, and nymphs mature to adult in less than two months.
- Fun Facts: Populations as high as 30,000 to 250,000 Asian cockroaches per acre have been found in some areas!
Control of the Asian cockroach can be particularly difficult because of its ability to fly. However because it tends to be drawn to light and active during the day, particularly at dusk – often resting or walking on lit TVs, its presence in the home is much more evident than other cockroaches that harbor in walls and crevices during the day and come out only at night.
A fact sheet from the University of Florida notes that "traditional treatments using residual sprays inside and around the perimeter of a structure are ineffective due to numerous infestations in mulched and wooded areas. Plus, adults enter homes through windows and doorways, avoiding areas typically treated for control of German cockroaches.
"Sodium vapor lamps for security lighting and yellow incandescent bulbs for porch lighting are both less attractive to adults and would thereby reduce the attraction of adult insects to lighting near buildings. Although Asian cockroaches are susceptible to all pesticides, toxic pelletized baits scattered outdoors have provided the most reliable control."