Clay preference and particle transport behavior of Formosan subterranean termites (Isoptera: Rhinotermitidae): A laboratory study

Abstract

Although preference and utilization of clay have been studied in many higher termites, little attention has been paid to lower termites, especially subterranean termites. The Formosan subterranean termite, Coptotermes formosanus Shiraki, can modify its habitat by using clay to fill tree cavities. Here, the biological significance of clay on C. formosanus was investigated. Choice tests showed that significantly more termites aggregated in chambers where clay blocks were provided, regardless of colony group, observation period, or nutritional condition (fed or starved). No-choice tests showed that clay had no observable effect on survivorship, live or dry biomass, water content, and tunneling activity after 33-35 d. However, clay appeared to significantly decrease filter paper consumption (dry weight loss). Active particle (sand, paper, and clay) transport behavior was observed in both choice and no-choice tests. When present, clay was preferentially spread on the substrate, attached to the smooth surfaces of the containers, and used to line sand tunnels. Mechanisms and potential application of clay attraction are discussed.

Water Transport byCoptotermes formosanus(Isoptera: Rhinotermitidae)

“…Utilization of soil particles to construct the nest and galleries and modify the microenvironment (particularly moisture and temperature) has been documented by previous researchers (Wood 1988, Jouquet et al 2002, Henderson 2008. Likewise, favoring one soil type over another for search tunnel formation has been reported (Cornelius 2005, Li and Su 2009, Cornelius and Osbrink 2010, Gautam and Henderson 2012, Wang and Henderson 2014. Su and Puche (2003) suggested that C. formosanus may transfer water from high-moisture sand to low-moisture sand but there was no mention of how this was accomplished.…”

Effects of clay materials and moisture levels on habitat preference and survivorship of Formosan subterranean termite,Coptotermes formosanusShiraki (Blattodea: Rhinotermitidae)

“…Such behaviors may result from tunnel excavation and subsequent transport processes (Li & Su, 2008;Lee et al, 2020). Some evidence also showed that these behaviors may be important for the foraging of lower subterranean termites because they preferred to aggregate and feed on food which was artificially covered/filled with clay (Wang & Henderson, 2014;Wang, Henderson & Gautam, 2015;Xiong et al, 2018a). Previous studies showed that moisture conditions of substrates are important for the survival of subterranean termites (Sponsler & Appel, 1990;Cornelius & Osbrink, 2010;.…”

“…Wang, Henderson & Gautam (2015) found that C. formosanus preferred to aggregate in chambers with field-collected clay. Also, termites preferentially used clay to cover the smooth surface of containers and construct shelter tubes (Wang & Henderson, 2014;Wang, Henderson & Gautam, 2015). Xiong et al (2018a) reported that significantly more C. formosanus and Reticulitermes guangzhouensis Ping aggregated and fed in baiting containers filled with bentonite, a clay mineral, than unfilled containers.…”

Super Absorbent Polymers Buried within Dry Soil Attract Formosan Subterranean Termites (Blattodea: Rhinotermitidae)

“…Suran and Rust [22] reported that 3% xylose in the food (paper discs) significantly increased the intake and horizontal transfer of hexaflumuron among individuals of Reticulitermes hesperus Banks, and caused significantly higher termite mortality than that of hexaflumuron alone. Other reported termite attractants include wood-rotting and soil fungi [23][24][25][26][27], decayed wood extract [28], carbon dioxide [29,30], clay materials [11,31,32], and even some sport drinks [33].…”