Many carry approximately 50 different
microorganisms (such as Salmonella and
Shigella), poliomyelitis, and Vibrio cholerae,
the causative agent of cholera.
Cockroaches spread undesirable organ-
isms through contact with food, especially
through biting and chewing. Although they
prefer foods that contain a large amount of
carbohydrates, they will feed on any sub-
stance that humans will consume, as well as
on human waste, decaying materials, dead
insects (including other cockroaches), shoe
linings, and paper and wood materials. Cock-
roaches are most active in dark areas and at
night, when less human activities exist.
These pests multiply rapidly by monthly
production of small egg cases that may con-
tain 15 to 40 eggs. The egg case is deposited
in a hiding place for added protection.
Young cockroaches begin feeding on the
same material as the adults shortly after they
hatch. Immature cockroaches look like
adults except that they are smaller and do
not have wings. They develop wings after
growing larger and shedding their skin sev-
eral times. Cockroaches live up to over a year
and mate several times.
Identification of the specific kind of cock-
roach infesting an establishment can aid in
the determination of the control technique.
Three cockroach species most commonly
invade establishments in the United States.
However, the field cockroach (Blatella vaga),
is spreading to domestic premises in parts of
the southern United States.
Species
German Cockroach (Blatella germanica)
The German cockroach is 13 to 20 mm
long and pale brown, with two dark-brown
stripes behind the head. Adults of both sexes
have well-developed wings. The female car-
ries the egg case protruding from the tip of
the abdomen until hatching occurs. During
the approximate lifetime of 9 months, an
adult female produces approximately 130
offspring.
In food establishments, German cock-
roaches can infest the main processing or
preparation rooms in addition to storage
areas, offices, and welfare facilities. They
prefer to inhabit warm crevices near heat
sources and are not usually found in storage
areas below ground level. German cock-
roaches are especially common in restau-
rants and may be found from floor to ceiling
levels in rooms.American Cockroach (Periplaneta
americana)
This species is approximately 40 to 60 mm
long and is the largest cockroach in the
United States. Adults are reddish-brown to
brown, and the young are pale brown. The
female hides egg cases as soon as they are
produced. This species produces more young
than does the German cockroach because
the adult female lives for 12 to 18 months,
lays as many as 33 egg cases, and produces
approximately 430 offspring.
American cockroaches tend to inhabit
open, wet areas, such as basements, sewers,
drainage areas, and garbage areas, although
this species may be found in storage rooms.
They tend to stay in places that are slightly
cooler and have larger cracks and crevices
than does the German cockroach. This
species is most frequently found in large stor-
age areas below ground level, on loading
docks, or in basements of foodprocessing
plants.Oriental Cockroach (Blatta orientalis)
The Oriental cockroach is shiny, dark
brown to black and approximately 25 mm
long. The wings are short in the male and
absent in the female. Young cockroaches of
this species are pale brown. Egg cases from
the females are hidden soon after their for-