SOIL ORGANISMS - Soil Ecology - page 315

substantial reductions to termite species richness and large changes in community structure.
In a Cameroon rainforest, Eggleton et al. (1996) reported a markedly-reduced species
richness (also biomass and abundance) in plots recently cleared and either replanted with
young trees or left as a weeded fallow, in comparison with nearby primary forest and
older wooded sites. Over three samplings, species richness varied from 4 to 13 in the first
category and 28 to 56 in the wooded plots. Soil-feeding termites were most severely
reduced by clearing. Wood et al. (1982) found an influx of savanna species into the
disturbed plots they studied in a rainforest environment in Nigeria. The study sites used
by Eggleton et al. (1996) were located ca. 40 km from the forest:savanna border while
that of Wood et al. was sited in a riparian forest within a savanna environment, where a
large pool of savanna species was present nearby. Cultivation markedly reduced the
diversity of termite communities in all locations studied (Wood, 1996).

4.3.2.5 Interactions between termites

Termites are territorial animals; colonies defend their nests and the surrounding areas
within which they forage and have the ability to identify individuals from other colonies
or species as 'not-self' (Shelton and Grace, 1996). Both inter- and intra-specific antago-
nisms have been demonstrated between termites of a number of species and there is
good reason to believe that this is of general occurrence. Adams and Levings (1987)
report inter- and intra-specific battles at territory borders and Darlington (1982) describes
finding dead soldiers of Macrotermes michaelseni in underground galleries as evidence
of battles near territory borders. However, not all inter- and intra-specific interactions
result in aggressive behaviours (Shelton and Grace, 1996).
Territory area is clearly related to colony size. Areas reported range from 9.5 to 338
(average 92 for the grass-harvesting African termite Hodotermes mossambicus
(Nel, 1968), from 500 to 800 depending on colony size for three species living in
Panamanian mangrove forests (Levings and Adams, 1984; Adams and Levings, 1987)
and was ca. 7800 for a colony of the fungus-cultivating termite Macrotermes
michaelseni in Kenya (Darlington, 1982).

4.3.2.6 The natural enemies of termites

As concentrated parcels of energy and nutrient elements, termites are attractive prey items
and are subject to considerable pressure from invertebrate and vertebrate predators, both
within and outside their nests. The primary defence of the colony is that provided by the
nest which few non-specialised predators can breach, either because of inaccessibility
within arboreal or subterranean locations or through the protection afforded by strong
epigeal nest structures. Nonetheless, a number of mammals are successful specialist
termite predators (Table III.15) and common adaptations in the most highly specialised
include the possession of strong claws, spatulate forelimbs, reduced teeth and a long, sticky
and prehensile tongue which is extruded to extract termites from their galleries.