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

found in deserted termite mounds (Roth and Willis,
1960).
Few cockroaches have been found in nests of Hymenoptera
other than ants. The minute (3 mm) species
Sphecophila polybiarum inhabits the nests of the vespid
wasp Polybia pygmaea in French Guiana (Shelford,
1906b). Apparently the cockroaches feed on small fragments
of prey that drop to the bottom of the nest when
wasps feed larvae. Parcoblatta sp. (probably Parc. virginica)
are commonly found (68% of nests) scavenging
bits of dropped prey and other colony debris in subterranean
yellowjacket (Vespula squamosa) nests at the end
of the colony cycle (MacDonald and Matthews, 1983).
Similarly, Oulopteryx meliponarum presumably ingest
excreta and other debris scattered by the small stingless
bee Melipona. Additional associations are discussed in
Roth and Willis (1960).
Cockroaches living in the nests of social insects profit
from protective services, a favorable microclimate, and a
stable food supply in the form of host-stored reserves and
waste material. The only benefit to the hosts suggested in
the literature is the opportunity to scavenge the corpses
of their guests. Ants generally ignore live Attaphila in the
nest (Wheeler, 1900), but the mechanism by which the
cockroaches are integrated into colony life has not been
studied. Like other inquilines, however, the cuticular hydrocarbons
of these cockroaches may mimic those of
their hosts. Gas chromatography indicates that the surface
wax of Ps. yumotoi is similar to that of their ant hosts
(T. Yumoto, pers. comm. to LMR), but it is yet to be determined
whether these are acquired from the ants by
contact or ingestion, or if they are synthesized de novo.
Cuticular hydrocarbons are easily transferred by contact
between two different species of cockroaches. After 14
days in the same container N. cinerea and R. maderae
merge into one heterospecific group with cuticular
profiles that show characteristics of both species (Everaerts
et al., 1997). Ants can acquire the hydrocarbons of a
non-myrmecophile cockroach (Supella longipalpa) via
physical contact; these ants are subsequently recognized
as foreign by their nestmates and attacked (Liang et al.,
2001). Individuals of Attaphila fungicola spend so much
time licking soldiers (Wheeler, 1910) that these myrmecophiles
may be internally acquiring and then reusing
epicuticular components of their host.
Vertebrate Burrows
Most records of Blattaria in vertebrate burrows come
from deserts (discussed below), as the high moisture content
of these habitats is advantageous in arid environments.
Cockroach food sources in these subterranean
spaces include organic debris, and the feces, cached food,
and dead bodies of inhabitants (Hubbell and Goff, 1939).
Roth and Willis (1960) indicate that cockroach species
found in animal burrows are usually different than those
that inhabit caves. Richards (1971), however, suggests
that burrows may be important as intermediate stops
when cockroaches move between caves, and gives as example
the often cavernicolous species Paratemnopteryx
rufa found in wombat burrows.
Bird Nests
Cockroaches are only rarely associated with the shallow
cup-type nest typical of many birds. The one exception
known to us is Euthlastoblatta facies, which lives in large
numbers among twigs in the nests of the gray kingbird in
Puerto Rico (Wolcott, 1950). Most records are from the
nests of birds that breed gregariously and construct pendulous,
teardrop-shaped nests up to 1 m long (Icteridae)
or large, hanging apartment houses of dry grass (Ploceinae).
Roth (1973a) collected about 10 species of cockroaches
in the pendulous nests of an icterid (probably the
oriole, Cassicus persicus) in Brazil. Schultesia lampyridiformis
was found in 2 of 7 nests of Cassicus about 18 m
above ground in the Amazon. Van Baaren et al. (2002)
found 5 species in icterid bird nests in French Guiana:
Schultesia nitor, Phoetalia pallida, Pelmatosilpha guianae,
Chorisoneura sp., and Epilampra grisea. Immature cockroaches
were common in the nests of Ploceinae in Madagascar
and the Ivory Coast; all nests of Foundia spp. examined
in Madagascar harbored cockroaches restricted
to this habitat (Paulian, 1948). Griffiniella heterogamia
lives in nests of a social weaver bird in southwest Africa
(Rehn, 1965). Most icterid nests inhabited by the cockroaches
were abandoned, and a few carried the remains
of dead young birds. The cockroaches are probably scavengers
and may also occupy the nests while birds are present
(Roth, 1973a).
In Caves and Cave-Like Habitats
Cockroaches are well represented in caves throughout the
tropics and subtropics, from 30N to 40S of the equator;
they are uncommon in temperate caves (Izquierdo and
Oromi, 1992; Holsinger, 2000). Except for rare collections
of Arenivaga grata and Parcoblatta sp., no cave cockroaches
occur in the continental United States (Roth and
Willis, 1960; Peck, 1998). The biology of cave-dwelling
cockroaches has been studied most extensively in Trinidad
and Australia. In Guanapo Cave in Trinidad, Eublaberus
distanti is dominant, with Blab. colloseus and
Xestoblatta immaculata also found (Darlington, 1995–
1996). These three species, as well as Eub. posticus, are also
found in the Tamana Caves (Darlington, 1995a). Six
cockroach species are reported from caves of the Nullarbor
Plain of southern Australia: Polyzosteria mitchelli,
HABITATS 51