Ecology, behavior and bionomics: functional response of Heterotermes tenuis Hagen (Insecta: Blattaria: Isoptera: Rhinotermitidae) in forests of the Colombian Orinoquía.

Background: Land use intensification may affect diversity, abundance, and functional morphological traits (FMT) related to dispersal, food acquisition, digestion, and nesting in some insects, possibly impacting their ecological role. Most studies of termites on the effects of afforestation focus on diversity and abundance, but changes in FMT have yet to be studied.

Aim: To better understand the response mechanisms to land use intensification, we compared the FMT of the worker and soldier caste of Heterotermes tenuis among Pinus caribaea plantations of four different ages and gallery forests of the Colombian Orinoquía.

Methodology: We measured thirty-eight FMTs in the worker and soldier castes of H. tenuis from gallery forests and pine plantations. Then, we used a Community-Weighted Mean (CWM), a PERMANOVA, and a nonmetric multidimensional scaling (NMDS) to estimate the possible effect of land use type on the FMT of both castes. We selected the FMTs with the lowest intraspecific coefficient of variation (CV) from each caste to compare their size among the land use types and pine plantation ages.

Results: Land use type had a more significant impact on the FMT size of pine plantation workers than the age of the afforestation. FMT of the worker caste tends to be larger in gallery forests than in pine plantations, while the results were inconclusive for soldiers.

Conclusion: The results suggested a homogenization mainly of the feeding FMT of the worker caste of H. tenuis in pine plantations associated with the increase in the softwood food resource of P. caribaea.