ECOLOGY AND BEHAVIOR How Far Can the Red Palm Weevil (Coleoptera: Curculionidae) Fly?: Computerized Flight Mill Studies With Field-Captured Weevils M. S. HODDLE, 1,2,3 C. D. HODDLE, 1 J. R. FALEIRO, 4 H. A. F. EL-SHAFIE, 5 D. R. JESKE, 6 AND A. A. SALLAM 5 J. Econ. Entomol. 108(6): 2599–2609 (2015); DOI: 10.1093/jee/tov240 ABSTRACT Adult Rhynchophorus ferrugineus (Olivier) captured in pheromone-baited traps in com- mercial date palm orchards in the Al Ahsaa Directorate, Kingdom of Saudi Arabia, were used in comput- erized flight mill studies to determine the flight characteristics of this highly invasive and destructive palm pest. Flight mill studies were run at three different time periods, winter (December), spring (March), and summer (May). Of the 192 weevils tethered to flight mills 30% failed to fly > 1 km. Of those weevils flying > 1 km (n ¼ 139), 55% flew > 10 km, and of these flyers 5% flew > 50 km in 24 h. Fly- ing weevils exhibited an average weight loss of 20–30% and nonflying control weevils lost 9–13% body weight in 24 h. Male and female weevils flying in summer (average laboratory temperature was 27  C) flew the longest average distances (25–35 km), exhibited highest weight reductions (30%), and great- est mortality rates (80%). Consequently, time of year not weevil sex or color morph had a consistent and significant effect on flight activity, weight loss, and survivorship rates. Flight activity was predomi- nantly diurnal commencing around 5:00 a.m. and peaking between 9–11:00 a.m. before tapering off. The distribution of flight distances combined across season and sex was mesokurtic (i.e., normally distributed). KEY WORDS color morph, dispersal, flight, kurtosis, Saudi Arabia Invasive insect pests can be extremely damaging to agri- cultural, natural, and urban areas, causing significant eco- logical and economic damage (Kenis et al. 2009, Simberloff et al. 2013). Consequently, these unwanted species cost hundreds of millions of dollars each year in direct losses and expenses associated with management efforts that attempt to reduce populations to less damag- ing levels (Pimentel et al. 2005, Kovacs et al. 2010, Van Driesche et al. 2010, Simberloff et al. 2013). Therefore, when introduced insects become pestiferous in adventive areas, studies examining their dispersal capabilities can aid in determining biotic and abiotic factors that may in- fluence rates and direction of spread, and dispersal path- ways (Lopez et al. 2014). A collective understanding of factors influencing the spread of invasive pests may help with the development of detection, monitoring, contain- ment, and control plans (David et al. 2014). Red palm weevil, Rhynchophorus ferrugineus (Oliv- ier), (Coleoptera: Curculionidae) is a pest of coconut palms, Cocos nucifera L. (Arecales: Arecaceae) (Giblin- Davis et al. 2013) in its native range, the northern and western regions of continental southeast Asia (i.e., northern Thailand, Vietnam, and Cambodia), Sri Lanka, and the Philippines (Rugman-Jones et al. 2013). Accidental introduction of R. ferrugineus into regions outside of the native range occurred via the movement of live palms infested with weevils (Giblin-Davis et al. 2013) with the first record being in the United Arab Emirates in 1985 (Faleiro et al. 2012). R. ferrugineus has been recorded attacking >40 palm species in 23 genera and has caused extensive mortality of Canary Is- land date palms (Phoenix canariensis Chabaud) in the Mediterranean and date palms (Phoenix dactylifera L.) (both Arecales: Arecaceae) in the Middle East and North Africa (Faleiro 2006, Faleiro et al. 2012, Giblin- Davis et al. 2013, Murphy and Briscoe 1999). The invasion pattern exhibited by R. ferrugineus is repre- sentative of a stratified dispersal process (Hengeveld 1989), which is a combination of: 1) rapid long-distance dispersal mediated by either abiotic factors (e.g., wind) or biotic factors (e.g., anthropogenic movement), and 2) short-distance localized dispersal via flying or walk- ing within invaded habitats (Hengeveld 1989, Petit et al. 2008). Adult R. ferrugineus are large insects (2–3 cm long and 1 cm wide; Giblin-Davis et al. 2013) exhibiting variable coloration that is commonly composed of an 1 Department of Entomology, University of California, Riverside, CA 92521. 2 Center for Invasive Species Research, University of California, Riverside, CA 92521. 3 Corresponding author, e-mail: mark.hoddle@ucr.edu. 4 Food and Agriculture Organization of the UN, Date Palm Research Centre, Ministry of Agriculture, PO Box 43, Al-Hassa 31982, Kingdom of Saudi Arabia. 5 Date Palm Research Center of Excellence, King Faisal University, P.O. Box 400, Al Ahsaa-31982, Kingdom of Saudi Arabia. 6 Department of Statistics, University of California, Riverside, CA 92521. VC The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. 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