Range expansion and population dynamics of Bactrocera carambolae in Roraima, Brazil

The carambola fruit fly Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae) is the main pest that threatens Brazilian fruit production, and can cause serious economic losses. Native to southeast Asia, B. carambolae was introduced in Brazil in 1996 and is currently found in the states of Amapá, Roraima and northern Pará, where an eradication program is underway. In this study, we studied the range expansion of B. carambolae and the association of climate with seasonal dynamics in Roraima, Brazil, from January 2013 to December 2020. Monitoring of B. carambolae adults was carried out through Jackson and McPhail trapping. The highest densities of B. carambolae occurred in the northeast region of Roraima. Low densities occurred in central Roraima, and a single outbreak was observed in south Roraima in 2014, but it was eradicated. Pest abundance was positively correlated with air relative humidity. These results can assist with control efforts and eradication programs of B. carambolae by indicating the periods with higher pest pressure and potential regions for pest establishment. This study will help to improve strategies for surveillance and host fruit transport.