Fine-scale spatial distribution of captured indigenous and marked wild-type navel orangeworm in a kairomone-baited mass trapping system

Amyelois transitella (Walker), navel orangeworm (NOW; Lepidoptera: Pyralidae), is a primary pest of almonds and pistachios, as well as a secondary pest of walnuts in California.  Currently, populations are generally monitored through the use of wing traps baited with female NOW pheromone and egg traps baited with almond press cake and crude almond oil. Wing traps provide an estimation of male flight activity while egg traps monitor female egg laying activity. Neither method is capable of providing accurate population estimates, nor is an egg trap capable of reducing the number of egg-laying (gravid) females. Recently, as a potential monitoring and management tool alternative, a proprietary kairomone-baited trap (Peterson Trap Company, LLC.) was developed to capture gravid female NOW. The objectives of this study were 1) to assess the efficacy of this trap using a mark and recapture protocol with mated female NOW and 2) to compare fine-scale spatial capture patterns of the marked females with indigenous populations. Results from this study will provide valuable information on NOW and baited-trap interactions under known densities and changing abiotic conditions, which will ultimately aid in mass-trapping design for implementation in an integrated pest management program.