Cockroache; Ecology, behavior & history - W.J. Bell

Fig. 3.2 Circadian activity of three nocturnal and one diurnal cockroach species in Costa Rican
rainforest. Solid bars are a measure of conspicuousness in the field; open bars indicate locomotor
activity in an outdoor insectary. Modified from Schal and Bell (1986).
Not all cockroach individuals are mobile on a nightly
basis. Kaplin (1996) found that 40% of individuals of the
desert cockroach Anisogamia tamerlana are active in a
single summer night. In females, locomotor patterns are
often associated with the reproductive cycle. In Blattella
germanica, activity increases when females are sexually
receptive and peaks during ovarian development. Locomotion
decreases when she is forming or carrying an
ootheca (Lee and Wu, 1994; Tsai and Lee, 2000). Nauphoeta
cinerea females likewise stop locomotor activity
shortly after mating; activity rhythms begin again after
partition (Meller and Greven, 1996b). In Rhyparobia
maderae daily activity gradually decreases in parallel with
the progressive development of eggs until the level characteristic
of pregnancy is reached (Engelmann and Rau,
1965; Leuthold, 1966). This inactivity is correlated with
a decreased requirement for locating food and mates;
females rarely forage during gestation. An increase in
movement prior to partition is associated with locating a
suitable nursery for forthcoming neonates. In juvenile
cockroaches activity is correlated with the developmental
cycle. Blattella germanica nymphs are active during the
first half of a nymphal stadium. During the last third of
the stadium, they remain in the harborage and move very
little (Demark and Bennett, 1994). Cockroaches may also
“stay home” during adverse weather. The activity of E.
lapponicus is inhibited by wind (Dreisig, 1971), and Lamproblatta
albipalpus individuals return to harborage when
disturbed by heavy rain (Gautier and Deleporte, 1986).
The distance traveled between shelter and sites of foraging
and other activity varies from 28 m in field populations
of Periplaneta americana (Seelinger, 1984) to no
more than a meter or two in female Macropanesthia rhinoceros
(D. Rugg, pers. comm. to CAN) and Lam. albipalpus
(Gautier and Deleporte, 1986).
There are a number of day-active cockroach species,
but little is known of their biology. Some, such as Euphyllodromia
angustata (Fig. 3.3), live in tropical rainforest.
Others inhabit more arid landscapes; these include
Fig. 3.3 The diurnal species Euphyllodromia angustata perching
on a leaf, Costa Rica. Note the dead edges of leaf holes and
the presence of epiphylls on the leaf surface, both of which are
included in the diet of many tropical cockroaches. Photo courtesy
of Piotr Naskrecki.
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