Termite Assemblage Pattern and Niche Partitioning in a Tropical Forest Ecosystem

Nationwide Termite Pest Survey Conducted in Taiwan as a Citizen Science Project

Information regarding the species composition and dispersal flight season of termites is crucial for termite management. The major obstacles to collecting such information are a lack of access to private buildings and shortage of workers to monitor and report on termite swarming. To overcome these difficulties, we launched a citizen science project in which members of the public and pest management professionals were invited to collect termite samples. We created the website, Taiwan Termite Identification Service, on which populace could log the collection information, and ship termite samples to our laboratory for identification. We also established a Facebook group, called the "Termite Forum," to publicize this project. A total of 3024 samples were collected from 2015 to 2020, and we identified the species of >93% of the samples. Based on 1499 samples collected from buildings, five structural termite pests were identified, and species composition in each county of Taiwan is available. According to 844 dispersal flight events, termite dispersal flight timing peak and degree of centralization were estimated using a Gaussian model. The collected data demonstrated that the invasive termite species, Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae), continued northward expansion. The first intercepted alate of Schedorhinotermes sp. (Blattodea: Rhinotermitidae) indicated that it may be a new invasive pest from Southeast Asia. This study reports on a successful case of a citizen science project where urban pest data were collected on a national scale.

Termite Communities along A Disturbance Gradient in a West African Savanna

(1) Background: Termites are important ecosystem engineers, crucial for the maintenance of tropical biodiversity and ecosystem functioning. But they are also pests which cause billions of dollars in damage annually to humans. Currently, our understanding of the mechanisms influencing species occurrences is limited and we do not know what distinguishes pest from non-pest species. (2) Method: We analyzed how anthropogenic disturbance (agriculture) affects species occurrences. We tested the hypothesis that strong disturbance functions as a habitat filter and selects for a subset of species which are major pests of crop. Using a cross-sectional approach, we studied termite assemblage composition along a disturbance gradient from fields to 12-year-old fallows in a West African savanna. (3) Results: We reliably identified 19 species using genetic markers with a mean of about 10 species—many of them from the same feeding type—co-occurring locally. Supporting our hypothesis, disturbance was associated with environmental filtering of termites from the regional species pool, maybe via its effect on vegetation type. The most heavily disturbed sites were characterized by a subset of termite species which are well-known pests of crop. (4) Conclusion: These results are in line with the idea that strong anthropogenic disturbance selects for termite pest species.

Vertical Distribution of Termites on Trees in Two Forest Landscapes in Taiwan

Termites are a key functional group in the forest ecosystem, but they damage trees. To investigate the termite infestation pattern on the whole tree, we cut 108 blackboard trees, Alstonia scholaris (L.) R. Br., and 50 Japanese cedars, Cryptomeria japonica (L. f.) D. Don, into sections. The bark surface and cross sections of the tree trunk were examined along the axes. A high percentage of blackboard trees (92.6%) was infested by fungus-growing termites, Odontotermes formosanus (Shiraki), but damage was limited to the bark surface at a 2-m height. The infestation rate of dampwood termites, Neotermes koshunensis (Shiraki), was only 4.6% (5/108), and all infestations were associated with trunk wounds. N. koshunensis was found at significantly higher portion of a tree than O. formosanus. Among 50 Japanese cedars, 20 living trees were not infested by any termites, but 26 of the 30 dead trees were infested by subterranean termites, Reticulitermes flaviceps (Oshima), which excavated tunnels in the trunk. The infestation rate at basal sections was higher than that at distal sections. Only one Japanese cedar tree was infested by another dampwood termite, Glyptotermes satsumensis (Matsumura). The two dominant termite species, O. formosanus and R. flaviceps, had subterranean nests and infested trees from bottom up. The two primitive termites N. koshunensis and G. satsumensis had low infestation rates and are most likely to infest trees by alates from top down. The niche segregation in trees of three termite families, Kalotermitidae, Rhinotermitidae, and Termitidae, was distinct.