Exploring population trends and potential chemical control of invasive Bulimulus snails in Florida citrus

Bulimulus bonariensis is an invasive land snail species in the Southeastern U.S. that has increasingly infested commercial crops in recent years, threatening productivity and causing concern among growers. In Florida citrus, B. bonariensis has been observed clogging microjets, defoliating trees within individual protective covers, and girdling young trees with pre-existing damage. There is very limited information available on population trends and potential chemical control of these snails, which are important to consider when developing management programs. To explore snail population trends, flat traps and pyramid traps were deployed alternately between trees and along grove edges at three sites and were checked for snails biweekly for one year. The count data revealed seasonal trends in snail activity that varied across sites, highlighting the importance of monitoring. The relative success of flat traps and pyramid traps also varied across sites, suggesting that either could serve as an effective monitoring strategy depending on environmental conditions. Additionally, heat maps indicated a random distribution of snails within fields, implying that whole grove management may be necessary. To evaluate potential chemical control, snails were treated with molluscicidal baits registered for use in Florida citrus and various insecticidal sprays not registered for snail control but are used by growers to control other citrus pests. Among the treatments, the molluscicidal baits and abamectin spray exhibited the highest mortality rates over a two-week period. The results of this study reveal pertinent information that may help growers manage B. bonariensis and mitigate its impact on citrus production.