Invasional meltdown on the Texas coast? Positive interactions between an invasive plant, an invasive ant, and a non-native moth on the endangered coastal tallgrass prairie
Positive interactions between invasive species may facilitate and amplify the invasive success of each interacting partner, leading to “invasional meltdowns.” Coastal tallgrass prairies, imperiled ecosystems along the Gulf Coast, are currently under threat by non-native species species from multiple trophic levels: the Chinese tallow tree (Triadica sebifera L.), the omnivorous tawny crazy ant (Nylanderia fulva Mayr), and most recently, an adventive, hypermetamorphic, herbivorous moth (Caloptilia triadicae Hodges). Previous research demonstrated that invasive Chinese tallow induces extrafloral nectar (EFN) in response to specific, chewing herbivores, and tawny crazy ants have been observed consuming tallow EFN on the prairie. However, the nature of interactions between these three species is currently unknown, and studies of tri-trophic interactions between spatially-associated, non-coevolved invasive species are underrepresented in the ecological literature. We hypothesize that invasive Chinese tallow, when attacked by the non-native moth, confers a nutritive resource to the ecologically dominant invasive ant. To determine the nature of the interactions between these species, we will experimentally manipulate EFN induction in potted Chinese tallow saplings using various levels of Caloptilia infestation, conduct complementary laboratory feeding trials with the ants, and measure the effect of ant exclusion on Caloptilia parasitism and predation on field-grown tallow trees.
Kathleen A Kargl, Chelse M Prather
Primary Advisor's Department
Stander Symposium poster
"Invasional meltdown on the Texas coast? Positive interactions between an invasive plant, an invasive ant, and a non-native moth on the endangered coastal tallgrass prairie" (2018). Stander Symposium Posters. 1401.