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Palm weevils, Rhynchophorus spp., are destructive pests of native, ornamental, and agricultural palm species. Of the 10 recognized species, two of the most injurious species, Rhynchophorus ferrugineus and Rhynchophorus palmarum , both of which have spread beyond their native range, are the best studied. Due to its greater global spread and damage to edible date industries in the Middle East, R. ferrugineus has received more research interest. Integrated pest management programs utilize traps baited with aggregation pheromone, removal of infested palms, and insecticides. However, weevil control is costly, development of resistance to insecticides is problematic, and program efficacy can be impaired because early detection of infestations is difficult. The genome of R. ferrugineus has been sequenced, and omics research is providing insight into pheromone communication and changes in volatile and metabolism profiles of weevil-infested palms. We outline how such developments could lead to new control strategies and early detection tools.

Heilipus lauri Boheman (Coleoptera: Curculionidae) is a specialist pest of avocado fruit and is considered an incursion risk for U.S. avocado producers. At the time work reported here was undertaken the flight capabilities of H. lauri were unknown. Consequently, proactive studies were undertaken to quantify aspects of this pest's flight capabilities to inform potential future control efforts. Flight mill studies were conducted in a quarantine laboratory to measure the dispersal capacity of H. lauri with respect to gender, mating status, and size on the single and repeat flight capabilities of weevils. Gender, mating status, and size did not significantly affect measured flight parameters. Average total distances flown and flight velocity, and mean maximum flight bout distances and durations significantly declined as weevil age increased and when weevils engaged in repeat flights. Survivorship rates were significantly reduced as the number of successive flights undertaken increased. The distribution of total average flight distances flown and total cumulative flight distances flown was platykurtic. The implications of these findings are discussed in terms of developing incursion management plans., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America.)

The efficacies of two trap types, bucket and Picusan traps, for capturing and retaining Rhynchophorus palmarum (L.), an invasive palm pest responsible for killing thousands of ornamental Canary Islands date palms (Phoenix canariensis Chabaud [Arecales: Arecaceae]) in San Diego County, CA, were compared. Digital video data were analyzed to determine how R. palmarum behavior toward each trap type affected capture and retention rates. Videography was conducted 24 h/d, 7 d/wk, for more than 7 mo resulting in 20,211 h of digital data for analysis. Weevil attraction to traps was observed only during daylight hours and no patterns in diel activity were found. Neither trap type tested captured 100% of weevils attracted to traps. Bucket traps suspended 1.5 m above the ground attracted 30% more weevils than ground deployed Picusan traps. Of those weevils attracted to bucket traps, 89% entered, 82% escaped, and 18% that entered traps were retained. Weevils that were not retained spent an average of 19 min 20 s entering and exiting entry holes and walking and flying around the bucket trap. By contrast, Picusan traps captured 89% of weevils that entered the trap. The time between weevils arriving (via walking or flight) on the sides of the Picusan trap and retention in the trap ranged between 90 and 376 s. These visual observations suggest that Picusan traps are more efficient than bucket traps for R. palmarum capture., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Rhynchophorus palmarum (L.) is an invasive pest responsible for killing thousands of ornamental Canary Islands date palms (Phoenix canariensis Chabaud) in San Diego County, CA. Two field experiments were conducted to compare the attractiveness of six different baits and two trap types. The tested baits were dates + water; dates + water + Saccharomyces cerevisiae; dates + water + S. bayanus; dates + water + S. pastorianus; 15% sugarcane molasses water solution mixed with 3% paraffinic oil, and a no bait control treatment. The two traps tested were white bucket traps (hanging 1.5 m above the ground and set on the ground) and black cone shaped Picusan traps (set on ground only). All traps were loaded with commercially available R. palmarum aggregation pheromone and the synergist ethyl acetate. Differences in weevil capture rates were observed across bait and trap types. Weevil captures were almost five times greater in Picusan traps compared to bucket traps that were hanging or placed on the ground. Adding dates and water alone or combined with S. cerevisiae to traps increased weevil captures compared to other baits and controls. Trap and bait types affected bycatch of nontarget arthropod species. In general, spiders, earwigs, and carabid beetles were most commonly recovered from Picusan traps, regardless of bait type. Scarab beetles, moths, and flies were found more frequently in bucket traps baited with molasses or dates mixed with S. bayanus. No effects of bait and trap type were associated with bycatch species richness., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The palm weevil, Rhynchophorus palmarum (L.), was first recorded in San Diego County, CA in 2011 and breeding populations were recovered from infested Canary Islands date palms, Phoenix canariensis, in San Ysidro, San Diego County, in 2015. This palm pest presents a significant threat to California's edible date industry as Phoenix dactylifera is a recorded host for this weevil. The flight capabilities of R. palmarum are unknown which limits understanding of rates of natural dispersal. In response to this knowledge deficit, 24-h flight mill trials were conducted with field-collected male and female weevils. A total of 87 weevils (49 females and 38 males) were used in experiments, ~6% failed to fly >1 km in 24 h and were excluded from analyses. Of those 82 weevils flying >1 km in 24 h, the average distance flown by males and females was ~41 and ~53 km, respectively. Approximately 10% of females flew >100 km in 24 h, with two (~4%) females flying >140 km. The maximum recorded distance flown by a male weevil was 95 km. Flight activity was predominantly diurnal and flying weevils exhibited an average weight loss of ~18% while non-flying control weevils lost ~13% body weight in 24 h. The combined flight distances for male and female weevils exhibited a heavy-tailed platykurtic distribution. Flight mill data for R. palmarum are compared to similarly collected flight mill data for two other species of invasive palm weevil, Rhynchophorus ferrugineus (Olivier) and Rhynchophorus vulneratus (Panzer)., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae: Lamiinae), is an invasive woodborer that poses a serious threat to urban and natural landscapes. In North America, this beetle is a quarantine pest, and populations are subject to eradication efforts that consist of the identification, removal, and destruction of infested host material, and removal or prophylactic treatment of high-risk host plant species. To enhance Asian longhorned beetle eradication protocols in landscapes with extensive host availability, we assessed the dispersal potential of male and female adults of varying age, mating, and nutritional status using computerized flight mills. In total, 162 individuals were tethered to computerized flight mills for a 24-h trial period to collect information on total distance flown, flight times and velocities, and number and duration of flight bouts. Adult Asian longhorned beetles (in all treatments) flew an average of 2,272 m within a 24-h period, but are capable of flying up to 13,667 m (8.5 miles). Nutrition and age had the greatest impacts on flight, with Asian longhorned beetle adults >5 d of age that had fed having greater overall flight performance than any other group. However, mating status, sex, and body size (pre-flight weight and elytron length) had a minimal effect on flight performance. This information will be useful for refining quarantine zones surrounding areas of infestation, and for providing greater specificity as to the risk the Asian longhorned beetle poses within invaded regions., (Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.)

The goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), is native to southern Arizona and is an invasive wood-boring beetle that has caused considerable mortality to native oak species in southern California. Assessing the dispersal capabilities of this woodborer may help to determine its potential environmental and economic risk within the invaded region, and possibly assist with the development of species-specific management strategies. The flight performance of A. auroguttatus adults under different age, mating, and nutritional status was assessed by tethering individuals to computerized flight mills for a 24-h trial period to collect information on total distance flown, flight times and velocities, number and duration of flight bouts, and postflight weight. The nutritional status and body size (i.e., elytron length) of A. auroguttatus adults had a significant influence on overall flight performance. Mating status and gender had no significant influence on total flight distance, duration, velocity, and flight bout time. Significant interactions between nutritional status and age were observed in the overall flight performance of A. auroguttatus, with decreased flight activity in old (approximately 6 d of age) starved individuals during a 24-h trial period. Overall, results of these flight mill assays indicate that A. auroguttatus is unable to disperse long distances across habitats that lack suitable oak hosts. This work supports the hypothesis that human-aided transportation via infested oak firewood from southern Arizona across the Sonoran desert likely caused the initial introduction, and subsequent satellite infestations of A. auroguttatus within southern California's native oak woodlands.