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Social wasps are amongst the most loathed exotic predators in New Zealand, with widespread adverse impacts on native ecosystems and fauna. Sustainable alternatives to pesticides are sorely needed i...

Epiphyas postvittana is a major horticultural pest in many countries, including New Zealand. Recently, two minor components (E)-11-tetradecen-1-ol and (E)-11-hexadecenyl acetate were found to increase the attraction of a previously identified two-component sex pheromone (95:5 blend of (E)-11-tetradecenyl acetate [E11-14:Ac] and (E,E)-9,11-tetradecadienyl acetate [E9,E11-14:Ac]) of Epiphyas postvittana. We hypothesised that the interaction between these minor components and the behavioural antagonist (Z)-11-tetradecenyl acetate (Z11-14:Ac) would modulate its antagonistic effect. The effect of increasing the ratio (0.5—10%) of Z11-14:Ac was tested in traps baited with E11-14:Ac and E9,E11-14:Ac (95:5), with or without the addition of the two minor compounds. Catch decreased as the percentage of Z11-14:Ac increased (χ2=108.74; d.f.=9; P

Vibrational pest management techniques involve the manipulation of the mating behaviour of the target species. Development of such techniques require a deep understanding of the pair formation process. Two types of bioassays were conducted to determine whether a vibrational disruptive approach could be used for Bactericera cockerelli. First, we conducted trials with either single individuals or pairs of a male and a female to ascertain whether B. cockerelli uses vibrational signals to achieve mating. Second, playback trials were conducted using two different female signals to manipulate the behaviour of males. Signals emitted during the trials were recorded using a laser vibrometer from the surface of a leaf where either single individuals or pairs of B. cockerelli were released. We described the communication phases that led to mating and the associated male and female signals. Pair formation started with a male call followed by a female response, which established a vibrational duet. During the female reply, the male searched for the female without emitting vibrational signals. Mating could be achieved if the male could maintain the female replies and reach her. In the playback trials, two different female playbacks attracted males to the signal source. Furthermore, males stimulated with female playbacks spent more time near the source of the signal than insects in the silent control group. We concluded that the B. cockerelli mating behaviour relies on vibrational signals and is potentially susceptible to vibrational manipulation, thus a future vibrational management technique could be developed to monitor or control this species.

Behaviours of insects can be manipulated by transmitting vibrational signals to host plants in order to develop pest management techniques. Bactericera cockerelli is an important pest and uses vibrations for mate-finding. In order to design a future control strategy for B. cockerelli, three different bioassays were performed to assess whether vibrational signals could affect relevant behaviours. Single males or pairs were treated with a female playback in test 1 and 2, respectively. In test 3, mixed sex groups received either different disturbance playbacks. The use of a female playback significantly reduced the mating success of males, since they were attracted towards the source of the stimulus. Moreover, test 2 revealed that B. cockerelli females are competitive, since they used their signals to cover the playback and to duet with males, while in test 3, the disturbance playback, consisting of broadband noises significantly reduced male signalling activity. However, none of the treatments of test 3 negatively affected the mating success of males, which tended to mount the other conspecifics present on the same leaf. The role of vibrations in sexual communication and their potential application as control technique for B. cockerelli are discussed as well.

In response to the confirmed detection of the light brown apple moth, Epiphyas postvittana, in California, approximately 53,000 pheromone-baited Jackson traps were deployed and more than 246,000 males were caught (February 2007–February 2010). Approximately 46,000 manually entered catch records were corrected for errors and converted into catch per trap per day. As empty trap data (zeros) were not recorded, we added zeros between first and last catch for each trap based on the stated servicing period (~30,000), before analyzing for trends. Residual data error rate was estimated as 1.5 %. San Francisco and Santa Cruz counties had relatively high trap catches immediately upon trap set, and remained the leading population centers, while most other counties showed a more general trend of a slow build-up in catch over time (12 counties). An exponential increase in trap catch was observed in four counties with sufficient data. The pattern of spread indicated natural, as well as anthropogenic-assisted spread rates, with populations appearing well ahead of the invasion front. This jump dispersal is probably due to movement of host plants, unsurprising since eggs of this polyphagous moth are readily laid on foliage. There was evidence of seasonality in spread, probably linked to the phenology of the insect. There was a positive relationship between catch and known host tree preference, suggesting that trap placement in preferred hosts could add sensitivity to future surveys. Recommendations include the improved provision of data acquisition by telecommunications, standardization of data input, more archiving, and frequent analysis of trap catches. The rapid rate of population growth demonstrated in two counties and spread across many others supports the hypothesis of the recent arrival of E. postvittana in California.

Vespid wasps (Vespula vulgaris L. and V. germanica Fab. Hymenoptera; Vespidae) are highly abundant in 1 million ha of New Zealand's indigenous beech forests (Nothofagus spp.) and have had detrimental effects on the New Zealand native fauna. This hyperabundance is due in part to the vast supply of carbohydrate-rich honeydew produced by scale insects Ultracoelostoma spp. native to New Zealand. Current control methods include the use of wet cat food as a protein source with insecticide as a lure-and-kill-based system, but there are problems with fresh baits degrading rapidly, and a more durable formulation would enable the expansion and longevity of wasp control. Four crude protein baits were tested for vespid attraction. Green-lipped mussels had the highest vespid catch of the crude baits tested, and aged and fresh mussels were equally attractive. From headspace analysis of the green-lipped mussel volatiles, a series of butanoate esters, 3-octanone and 1-octen-3-ol were identified as possible attractants. These compounds were tested individually and in various blend combinations for the attraction of Vespula wasps in matagouri vegetation at the edge of beech forests. We found synergistic effects between single attractive compounds when tested in various combinations, and the multicomponent lures were more attractive to these wasps than heptyl and octyl butanoate, previously identified attractants for vespid species. The new multicomponent lures could form the basis for a new generation of attractants for social wasps that can provide sustained control methods for invasive vespid wasps.

The sterile insect technique (SIT) potentially provides a socially acceptable approach for insect eradication of new pest incursions. The light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), was discovered in Berkeley (CA, USA) in 2006, leading to an incursion response that included this technology. In this study, we assessed factors affecting mating success from a bisex release of irradiated moths: effects of radiation dose on male multiple mating, male flight competition, female sex pheromone titre and attractiveness of irradiated females to males, and identification of successful mating in vineyards of either irradiated or wild males (identified by isotope analysis of spermatophores from sentinel females). There was a significant negative relationship between male radiation dose and mating frequency. In head-to-head flights of irradiated males against non-irradiated males to a pheromone lure in a wind tunnel, irradiated males reached the lure first only 31% of the time. With increasing radiation dose, the production of the major sex pheromone component in females, (E)-11-tetradecenyl acetate, dropped, from 0.7 ± 0.1 ng per female in non-irradiated females to 0.2 ± 0.07 ng per female when irradiated at 300 Gy. Male catch was reduced to 11% of control females in traps containing females irradiated at 300 Gy. Isotope analysis of spermatophores found in the bursa copulatrix of females indicated that mating success of irradiated males inside the live (entry-only) traps containing virgin females was lower (13.1 ± 3.3%) than suggested by male catch (21.2 ± 3.8%) in pheromone traps, the current standard for assessing field competitiveness. Impacts of irradiation on male and female moth fitness should be taken into account to improve estimates of irradiated to wild male E. postvittana overflooding ratios needed for population suppression.

A new four-component sex pheromone blend for light brown apple moth (Epiphyas postvittana) was examined for efficacy of communication disruption in laboratory and field trials. Vineyard trials using SPLAT LBAM™ examined disruption of traps in the presence of: a) the current two-component ((E)-11-tetradecenyl acetate and (E,E)-9,11-tetradecadienyl acetate, 95:5), b) a new four-component blend ((E)-11-tetradecenyl acetate and (E,E)-9,11-tetradecadienyl acetate plus (E)-11-tetradecen-1-ol and (E)-11-hexadecenyl acetate (10:0.5:0.1:0.05)), c) higher ratio of the two new compounds (10:0.5:10:10), d) four compounds with an antagonist ((Z)-11-tetradecenyl acetate) added, e) three compounds with antagonist minus the most expensive component ((E,E)-9,11-tetradecadienyl acetate), compared to f) untreated controls. In the laboratory, 69.0% of untreated pairs mated, and communication was suppressed by both attractive blends (41.1% communication (P = 0.024, two-component blend), and 18.4% communication (P = 0.003, four-component blend)). In vineyards, totals of 24,776 and 41,053 male moths were caught in the two trials, respectively, to delta traps baited with four-component lures and virgin females. Communication disruption was achieved at a higher level with a four-component blend for 13/14 weeks in disruption trial one and for 10/10 weeks in disruption trial two, compared with the two-component blend. Disruption was on average improved by 12% with the four-component blend compared to the two-component blend (P = 0.091). Other blends were less effective at communication disruption. The best formulation released from SPLAT™ was only weakly attractive compared to rubber septa, so false trail following to point sources was unlikely to be as important as other mechanisms.

The volatile compounds emitted from uninfested apple seedlings, cv. Royal Gala, and apple seedlings infested with generalist herbivore Epiphyas postvittana larvae were sampled using headspace collection and analyzed by gas chromatography-mass spectrometry. Nine additional compounds were only detected in infested apple seedlings [including benzyl alcohol, (E)-β-ocimene, benzyl cyanide, indole, (E)-nerolidol, and four unidentified compounds]. Infested apple seedlings produced larger amounts of (Z)-3-hexenyl acetate, linalool, 4,8-dimethyl-1,3(E),7-nonatriene, methyl salicylate, β-caryophyllene, germacrene D, (E,E)-α-farnesene, and (Z)-3-hexenyl benzoate than uninfested plants. Female parasitoids flew exclusively upwind to infested and not to uninfested apple seedlings in wind tunnel choice tests and preferred infested leaflets in still air, even after the removal of larvae. The attraction of a parasitoid to infested apple seedlings in the laboratory and in the field to apple and many other plants in at least six families supports considerable generality of the tritrophic signaling process.

Light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), is the target of the sterile insect technique, but reduced moth fitness from irradiation lowers the effective overflooding ratio of sterile to wild moths. New measures of insect quality are being sought to improve field performance of irradiated insects, thus improving the cost effectiveness of this technique. Male pupae were irradiated at intervals between 0 and 300 Gy, and adult flight success was assessed in a wind tunnel equipped with flight track recording software. A dose response was evident with reduced successful search behaviors at higher irradiation doses. Irradiation at 250 Gy reduced arrival success to 49% of untreated controls, during 2-min assays. Mark-release-recapture of males irradiated at 250 Gy indicated reduced male moth recapture in hedgerows (75% of control values of 7.22% +/- 1.20 [SEM] males recaptured) and in vineyards (78% of control values 10.5% +/- 1.66% [SEM] recaptured). Males dispersed similar distances in both habitats, and overflooding ratios dropped off rapidly from the release point in both landscapes. Transects of traps with central releases proved to be an efficient method for measuring the quality of released males. Relative field performance of moths was greater than suggested by wind tunnel performance, which could be due to time differences between the two assays, two-minute wind tunnel tests compared with days in the field treatments. Release strategies involving ground releases should consider the effect of limited postrelease dispersal. Aerial release could solve this problem and warrants investigation.

With improvements in 3D-printing technology, the ability to convert the idea of an object quickly into an actual 3D object is becoming both more practicable and affordable. We have been developing a 3D-printed gear housing and a detachable sleeve mechanism with a variable number of rotating arms, to facilitate the testing of a variety of fruit y lures while controlling for environmental bias. The speed of the rotator mechanism is controlled using an adjustable DC step-down module and a series of 3D printed gears. Our current prototype runs on four AA batteries delivering 6V. For testing over longer timeframes or in remote areas, just about any power supply outputting between 5 and 40 volts can be attached. The model is small and has optional printed components that make the unit rain proof so it can be used for both laboratory and eld trials. The model can be printed on any 3D printer with a large enough stage. This model can be used to test lure blends for a variety of insects such as ies or beetles, in a variety of settings such as laboratories, pastures, orchards and forests.

With sensors and microprocessors becoming more affordable all the time it is now possible to build inexpensive environmental regulators for small insect colony boxes We designed and built a humidity regulator for xerophilic (dryloving) Nysius bugs Poorly ventilated insect rearing boxes can have an overly elevated humidity that can promote unwanted fungal growth especially if there is live plant material involved Air conditioned laboratories can have very low ambient humidity but the ideal humidity for an insect colony may be intermediate Direct and accurate measurement and control of humidity is now possible electronically using sensors and a fan to pump dry air into a humid space in a controlled fashion to regulate the humidity The potential exits for different sensors to be used to monitor different environmental variables and to trigger equipment to respond when an environmental threshold is reached Environmental control methods can be simple or elaborate depending on the colony requirements and budget A clock and memory card can be added to the microprocessor to record sensor data and event triggers This method has been successfully used to rear the wheat bug Nysius huttoni

Geographic Information Systems (GIS) have been used during major invasive insect incursion responses in New Zealand since about 1999. The exchange of local mapping software enabled sharing of data that could be reviewed and analysed by researchers and programme response personnel across the country to help develop invasive species control and response plans quickly. Two examples include the New Zealand response to the Argentine ant and painted apple moth invasions. Advances in web services have globalised delivery of information, and Google Earth in particular has offered novel value that has been explored with co-operators in USDA. Here, data were converted from a excel spreadsheet to *.kml format, plotted in various pre-determined ways and saved as a *.kmz file that could be emailed. Lower than desired analytical functionality was met by better forward planning of analyses for mapping. The population expansion of the light brown apple moth in California is offered as a case study to indicate how rapidly evolving tools can help surveillance programmes, and contrasts with earlier surveillance information management methods used in New Zealand.