arboreal nest structure
castes
 replacement of reproductives
defensive and aggressive behaviors
references

Arboreal nesting termites in coconut plantations of the north coast of New Guinea

New Guinea coconut plantations are colonized by three arboreal nesting termites species: Microcerotermes biroi, Nasutitermes princeps and Nasutitermes novarumhebridarum. Trees are exclusively colonized by a single colony as a consequence of mutual exclusion (intra- and inter-specific competition).

Arboreal nest structure

All three termite species use the coconut tree as nesting site and food source such as dead leaves laying on the ground. Termites forage most of the time under covered galleries. (_1099KB)


Royal cell and queen (Microcerotermes biroi)

Colonies are headed by a queen and a king living inside a royal cell. (_756KB)

The presence of eggs and young larva generally indicates the location of the royal cell inside the nest (_1919KB)

Microcerotermes biroi nest chambers communicate by small orifices easily obstructed by a soldier's head or walled up by the workers to isolate a damaged or invaded part of the nest (_266KB) M. biroi nests are sometimes invaded by N. princeps or by ants. 

Simplified caste system of Microcerotermes biroi, Nasutitermes princeps and N. novarumhebridarum (Isoptera, Termitidae)

Note: in termite developmental paths may vary largely from one species to another.

Replacement of  reproductives

Basically new termite colonies are founded by alates which leave an existing mature colony in swarms. After the nuptial flight alates pairs shed their wings and start to build a new nest. As a rule, new colonies are founded by a single pair of alates although in some species multiple alates are sometimes found (pleometrosis). Imagos which found a colony after a nuptial flight (primary reproductives) are fully pigmented and have well cut wing scales (wings break across a suture during dealation). 

By contrast, secondary reproductives differentiate in their parental colony after the dead (replacement reproductives) or a drop in the fertility (supplementary reproductives) of the primary reproductives. In species where colonies are composed of multiple nests, secondary reproductives may differentiate in a satellite nest (budding) when the connection with the main nest is broken or when the distance from the main nest reduces the influence of the functional reproductives. Secondary reproductives often live in polygynous (multiple queens _671KB) associations.

Secondary reproductives may arise from alates in the nest (adultoid neotenics), nymphs (nymphoid neotenics) or workers (ergatoid neotenics). Adultoids (1750KB) are morphologically indistinguishable from primary reproductives although their wings are sometimes imperfectly shedded or shorter and their pigmentation weaker. Ergatoids differentiate from workers and therefore never develop wings. Nymphoids (_497KB) lack wing scales but are recognizable by the presence of wing buds. As a rule, secondary reproductives are generally present in large number especially at the beginning of the replacement process. The capacity of each caste to differentiate into secondary reproductives varies largely from one species to another.

Defensive and aggressive behaviors

Worker and soldier behavior

Nasute worker and soldiers: alarm: rapid oscillatory movements ( 472KB)
Workers from Nasutitermes and Microcerotermes: bites
M. biroi soldiers: head-banging ( 57KB)
Nasute soldiers : spray of a defensive secretion

Interspecific interactions

Interspecific interactions are always agonistic.
In some plantations large colonies of N. princeps extended their territory by destroying colonies of M. biroi  ( N. princeps worker attacking a M. biroi soldier, 888KB). An experimental weakening of N. princeps allowed the recolonization of the habitat by M. biroi. ( maps of species distribution, 217KB)
M. biroi is a pioneer species which colonizes rapidly new habitats. ( map of species distribution, 55KB)

Intraspecific interactions

Either a lack of agonism, a moderate agonism or a strong agonism can be observed when individuals from two conspecific colonies meet. 

References

Leponce, M. 1996. Structure et dynamique d'une communauté de termites à nids arboricoles en cocoteraie néo-guinéenne. phD thesis, Université Libre de Bruxelles, 158 p. (supervisors: Prof. J.M. Pasteels & Dr. Y. Roisin, ULB). (4243KB)(FR & EN)

Leponce, M. ; Roisin, Y. ; Pasteels, J.M. 1995 Environmental influences on the arboreal nesting termite community in New Guinean coconut plantations. Environmental Entomology, 24 : 1442-1452.(866KB)

Leponce, M.; Roisin, Y. ; Pasteels, J.M. 1996 Reproductive mechanisms and dynamics of habitat colonization in Microcerotermes biroi (Isoptera: Termitidae). Ecological Entomology, 21 : 178-184.

Leponce, M.; Roisin, Y.; Pasteels, J.M. 1996 Intraspecific interactions in a community of arboreal nesting termites. Journal of Insect Behavior, 9 : 799-817.(874KB)

Leponce, M. ; Roisin, Y. ; Pasteels, J.M. 1997 Structure and dynamics of the arboreal termite community in New Guinean coconut plantations. Biotropica, 29 : 193-203.(1361KB)

Leponce, M. 1997 Reproductive strategies and community structure of New Guinean arboreal nesting termites. Bulletin & Annales de la Société royale belge d’Entomologie, 133 : 283-289.( 921KB)

Leponce, M.; Roisin, Y.; Pasteels, J.M. 1999 Community interactions between ants and arboreal-nesting termites in New Guinea coconut plantations. Insectes Sociaux, 46 : 126-130.(189KB)