Novel Tools & Strategies - Invertebrates
#Tranche 2: Strategic Objective 5 - Novel Tools & Strategies - Invertebrates# ##Novel tools, technologies and strategies need to be deployed to eradicate biotic threats.## Many of our current pest control strategies have unintended and detrimental effects on the surrounding environment. For example, heavy reliance on pesticides can result in non-target kill of native or beneficial invertebrates. We need new tools to effectively control pests while avoiding these unwanted side-effects. The ‘Novel Tools & Strategies – Invertebrates’ team aims to develop a new, landscape scale, invertebrate pest management tool by 2024. While working towards this goal, they are partnering with iwi and hapū to understand how new pest control tools and enhance kaitiakitanga and promote tino rangatiratanga. **Co-Leads** * Professor Phil Lester; Victoria University of Wellington * Dr Ocean Mercier; Victoria University of Wellington * Symon Palmer; Victoria University of Wellington **NOTE:** This tranche 2 investment is very closely linked to the tranche 1 project [Taking the Sting Out of the Common Wasp](https://data.bioheritage.nz/dataset/taking-the-sting-out-of-the-common-wasp)
BRIEF: Māori perspectives on new pest control
###Māori perspectives on potential new pest control### **March 2024** Genetic technologies could be very useful for pest control in Aotearoa New Zealand, but social acceptance and support is needed before these can be considered, developed and implemented. So, what do tangata whenua think of using gene-based technologies to protect taonga species? We spoke with Māori to gauge their views on two promising technologies for pest control: gene silencing and gene drive.
###Evaluating the use of gene drives for wasp control### **March 2024** Introduced wasps in Aotearoa New Zealand damage native ecosystems, harm human health, and threaten the beekeeping industry. Current pest control of wasps relies on spraying broad-spectrum insecticides across a landscape. However, gene drive technology is now recognised as a potentially revolutionary method for wasp control.
PAPER: Pest Insect Control in Māori Tradition
###Hōhā Riha: Pest Insect Control in Māori Tradition### **September 2022** **Mercier OR, Palmer S, King Hunt A 2022. Hōhā Riha: Pest Insect Control in Māori Tradition. Waka Kuaka: The Journal of the Polynesian Society 131(3): 259-286.** **ABSTRACT** Ongoing Māori connections to natural environments mean that tangata whenua ‘people of the land’ and mātauranga Māori ‘Māori knowledge’ must be key to identifying, designing and advancing national conservation strategies, including health of native species and making decisions about pest control. We revisit whakataukī ‘Māori proverbs’ and early ethnographic texts to explore how so-called pest insects were traditionally viewed by Māori. What species did Māori consider to be pests prior to European arrival? How were these managed? Was eradication a goal? Were insects ever considered riha ‘pests’ in “wild”, non-cultivated environments? We review accounts of damaging insects and their management strategies, which included extraction by hand, poisons, use of karakia ‘incantations’, fire and even biocontrol. These findings are reported within a hōhā riha ‘bothersome pests’ typology, indicating degrees of “pestiness”. Māori were pragmatic, turning “pests” into resources for other purposes. Māori were observers and participants in ecosystems, and many whakataukī link human behaviour to troublesome insects. We comment upon whakapapa ‘genealogy’ as an inclusive system of biodiversity and discuss Māori conceptions of “wilderness”. **KEYWORDS** Māori, mātauranga Māori ‘Māori knowledge’, whakataukī ‘proverbs’, pests, insects, anthropods, pest management
###Gene drive and RNAi technologies: a bio-cultural review of next-generation tools for pest wasp management in New Zealand### **October 2021** **Palmer S, Dearden PK, Mercier OR, King-Hunt A, Lester PJ 2021. [Gene drive and RNAi technologies: a bio-cultural review of next-generation tools for pest wasp management in New Zealand](https://scholar.google.com/scholar_url?url=https://www.tandfonline.com/doi/pdf/10.1080/03036758.2021.1985531%3Fcasa_token%3D_507Cxk5j4QAAAAA:UYMkU9uFUo-8eeTmQs6z0uximrBzKkeIaFFubdXFwqJmJC4CIB4dzT0TWpu9cA0mN204RLP_a0AaHpg&hl=en&sa=T&oi=ucasa&ct=ucasa&ei=RamoZraZN52A6rQP6o3e0Q8&scisig=AFWwaebw8MEJd3Xkffs1-LISchxv). Journal of the Royal Society of New Zealand: 1-18. ** **ABSTRACT** There is a global need for novel, next-generation technologies and techniques to manage pest species. We review work on potential step-changing technologies for large landscape (>1000 hectares) pest management of social Vespula wasps. We also review Māori perspectives on these controls to gauge social and cultural acceptability to research, test and use of novel controls. Approaches discussed are the use of gene silencing (RNAi) and gene drives (CRISPR-Cas 9) involving genetic modification, which has potential for pest control but vary in feasibility, cost, benefits and off-target risks. RNAi may be better suited for wasp control in high-value cropping systems due to scaling inefficiencies. Gene drives offer potential for large-scale control but would require legislative and wide social deliberation due to their status as genetic modification. Both RNAi and gene drives will require consultation with tangata whenua. Māori interest groups agreed that exotic wasps must be controlled and expressed aversion to non-targeted traditional control methods. We present a diversity of opinions in parallel with scientific research underscoring the need for continued dialogue with Māori. Novel biotechnological controls must satisfy a broad range of social and cultural criteria, receive regulatory approval, along with being demonstrated as safe, selective, and cost-effective. **KEYWORDS** Conservation; pest management; gene drives; RNAi; Māori; Indigenous engagement; CRISPR
PAPER: Can dsRNA control invasive Argentine ant?
###Can immune gene silencing via dsRNA feeding promote pathogenic viruses to control the globally invasive Argentine ant?### **October 2022** **Felden A, Dobelmann J, Baty JW, McCormick J, Haywood J, Lester PJ 2023. [Can immune gene silencing via dsRNA feeding promote pathogenic viruses to control the globally invasive Argentine ant?](https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/eap.2755) Ecological Applications 33(2): e2755. https://doi.org/10.1002/eap.2755** **ABSTRACT** Pest control methods that can target pest species with limited environmental impacts are a conservation and economic priority. Species-specific pest control using RNA interference is a challenging but promising avenue in developing the next generation of pest management. We investigate the feasibility of manipulating a biological invader's immune system using double-stranded RNA (dsRNA) in order to increase susceptibility to naturally occurring pathogens. We used the invasive Argentine ant as a model, targeting the immunity-associated genes Spaetzle and Dicer-1 with dsRNA. We show that feeding with Spaetzle dsRNA can result in partial target gene silencing for up to 28 days in the laboratory and 5 days in the field. Dicer-1 dsRNA only resulted in partial gene knockdown after 2 days in the laboratory. Double-stranded RNA treatments were associated with significant gene expression disruptions across immune pathways in the laboratory and to a lower extent in the field. In total, 12 viruses and four bacteria were found in these ant populations. Some changes in viral loads in dsRNA-treated groups were observed. For example, Linepithema humile Polycipivirus 2 (LhuPCV2) loads increased after 2 days of treatment with Spaetzle and Dicer-1 dsRNA treatments in the laboratory. After treatment with the dsRNA in the field, after 5 days the virus Linepithema humile toti-like virus 1 (LhuTLV1) was significantly more abundant. However, immune pathway disruption did not result in a consistent increase in microbial infections, nor did it alter ant abundance in the field. Some viruses even declined in abundance after dsRNA treatment. Our study explored the feasibility of lowering a pest's immunity as a control tool. We demonstrate that it is possible to alter immune gene expression of pest species and pathogen loads, although in our specific system the affected pathogens did not appear to influence pest abundance. We provide suggestions on future directions for dsRNA-mediated immune disruption in pest species, including potential avenues to improve dsRNA delivery as well as the importance of pest and pathogen biology. Double-stranded RNA targeting immune function might be especially useful for pest control in systems in which viruses or other microorganisms are prevalent and have the potential to be pathogenic. **KEYWORDS** immunity; *Linepithema humile*; pest management; RNA silencing viruses
PAPER: Gene silencing to manage paper wasps
###Gene silencing for invasive paper wasp management: Synthesized dsRNA can modify gene expression but did not affect mortality### **January 2023** **Bulgarella M, Baty JW, McGruddy R, Lester PJ 2023. [Gene silencing for invasive paper wasp management: Synthesized dsRNA can modify gene expression but did not affect mortality](https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0279983&type=printable). PLoS One 18(1): e0279983. https://doi.org/10.1371/journal.pone.0279983** **ABSTRACT** Invasive paper wasps such as *Polistes dominula* are a major pest and problem for biodiversity around the globe. Safe and highly targeted methods for the control of these and other social wasp populations are needed. We attempted to identify potentially-lethal gene targets that could be used on adult paper wasps in a gene silencing or RNA interference (RNAi) approach. Double-stranded RNA (dsRNA) was designed to target genes for which silencing has proven lethal in other insects. dsRNA was provided either orally to foragers or directly injected into the wasps. We also provided the dsRNA unprotected or protected from degradation by gut nucleases in two different forms (lipofectamine and carbon quantum dots). The effects of oral delivery of 22 different gene targets to forager wasps was evaluated. The expression of five different genes was successfully reduced following dsRNA ingestion or injection. These gene targets included the FACT complex subunit spt16 (DRE4) and RNA-binding protein fusilli (FUSILLI), both of which have been previously shown to have potential as lethal targets for pest control in other insects. However, we found no evidence of significant increases in adult wasp mortality following ingestion or injection of dsRNA for these genes when compared with control treatments in our experiments. The methods we used to protect the dsRNA from digestive degradation altered gene expression but similarly did not influence wasp mortality. Our results indicate that while many of the same gene targets can be silenced and induce mortality in other insects, dsRNA and RNAi approaches may not be useful for paper wasp control. **KEYWORDS** Gene expression; RNA interference; Insects; Pest control; Double stranded RNA; Larvae; Small interfering RNA; Gene silencing
PAPER: Virus Dynamics in Varroa-Infested Bee Colonies
###Viral communities in the parasite *Varroa destructor* and in colonies of their honey bee host (*Apis mellifera*) in New Zealand### **May 2022** **Lester PJ, Felden A, Baty JW, Bulgarella M, Haywood J, Mortensen AN, Remnant EJ, Smeele ZE 2022. Viral communities in the parasite *Varroa destructor* and in colonies of their honey bee host (*Apis mellifera*) in New Zealand. Sci Rep 12(1): 8809. https://doi.org/10.1038/s41598-022-12888-w** **ABSTRACT** The parasitic mite *Varroa destructor* is a leading cause of mortality for Western honey bee (*Apis mellifera*) colonies around the globe. We sought to confirm the presence and likely introduction of only one *V. destructor* haplotype in New Zealand, and describe the viral community within both *V. destructor* mites and the bees that they parasitise. A 1232 bp fragment from mitochondrial gene regions suggests the likely introduction of only one *V. destructor* haplotype to New Zealand. Seventeen viruses were found in bees. The most prevalent and abundant was the Deformed wing virus A (DWV-A) strain, which explained 95.0% of the variation in the viral community of bees. Black queen cell virus, Sacbrood virus, and Varroa destructor virus 2 (VDV-2) played secondary roles. DWV-B and the Israeli acute paralysis virus appeared absent from New Zealand. Ten viruses were observed in V. destructor, with > 99.9% of viral reads from DWV-A and VDV-2. Substantially more variation in viral loads was observed in bees compared to mites. Where high levels of VDV-2 occurred in mites, reduced DWV-A occurred in both the mites and the bees co-occurring within the same hive. Where there were high loads of DWV-A in mites, there were typically high viral loads in bees. **KEYWORDS** Mitochondrial DNA; Haplogroup assignment; Viral communities; RNA-Seq; DWV-A; *Varroa destructor*; Honey bees; Genetic variation; PCR; Viral replication
PAPER: Ecological State Assessment Tool (ESAT)
###Ecological State Assessment Tool (ESAT): a cross-cultural natural resource management tool from Aotearoa, New Zealand### **July 2021** **Belcher SM, Mercier OR, Foley JP, Deslippe J. 2021. Ecological State Assessment Tool (ESAT): a cross-cultural natural resource management tool from Aotearoa, New Zealand. Pacific Conservation Biology 27(4): 464-480.** **ABSTRACT** A cross-cultural approach to conservation and natural resource management will enable resource managers to access the full potential of dual knowledge epistemologies and facilitate genuine co-management. To achieve this epistemological convergence in Aotearoa, New Zealand, a framework and an ecological assessment tool are required that can employ indicators from both neoclassical ecological science and indigenous science, in particular mātauranga Māori. The Ecological State Assessment Tool (ESAT) was developed to assess quantitative scientific data using Māori ecological indicators. ESAT models population or social data weighted according to an applied Māori ecological perspective. ESAT may be applied to any conservation project to integrate Māori ecological knowledge in resource management. We illustrate the utility of ESAT in a case study of how different conservation management practices affect the ecological health of a short-tailed bat colony (Mystacina tuberculata), Pekapeka O Puketītī-Piopio. Applying ESAT shows that although pest control programs were achieving management targets, social engagement had a significant effect on ecological health outcomes for the bats. ESAT may assist territorial authorities and the Crown to meet their resource management obligations to Māori under the Treaty of Waitangi, value mātauranga and provide a way for Māori and ecologists to conceptualise and understand each other’s epistemology. Furthermore, ESAT can be adapted to include any cultural or ecological indicators, enabling its application internationally. **KEYWORDS** co-management, cultural indicators, ecological indicators, Ecological State Assessment Tool, ESAT, indigenous ecological knowledge, Māori, Mystacina tuberculata, New Zealand, Pekapeka O Puketītī-Piopio, short-tailed bat.
PAPER: High-density trapping of social wasps
###Experimental high-density trapping of social wasps: target kairomones for workers or gynes for drones?### **August 2020** **Sullivan TES, Sullivan NJ, El-Sayed AM, Brierley S, Suckling DM 2020. [Experimental high-density trapping of social wasps: target kairomones for workers or gynes for drones?](https://scholar.google.com/scholar_url?url=https://www.tandfonline.com/doi/pdf/10.1080/00779962.2020.1802880%3Fcasa_token%3D217vSJ7sJlAAAAAA:G7gAX0gG63CDYGD_jylXbGLrrSVuiol9t5K580L8kF1EtBXQwtRs8C5NdaaZxj9aYOb6dXHaqin7wPM&hl=en&sa=T&oi=ucasa&ct=ucasa&ei=EqqoZunyCq6G6rQPgf3h-Ag&scisig=AFWwaeaepGlkRt-WuewopyqJeEmG) New Zealand Entomologist 43(2): 65-76. ** **ABSTRACT** 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 in *Fuscospora* (beech) forests. We tested a new semiochemical evaluation protocol to assess the extent of high-density trap competition as an indicator of mass trapping, in an open landscape adjacent to a beech forest near Cass (Canterbury, New Zealand), for potential worker or drone removal. We tested the kairomone lure using a before-after control-impact design at a 1-ha scale with a grid of 25 bucket traps as a high-density trapping treatment (three replicates). The trial was affected by a major inundation event and catches declined steadily in both treatments for the month following, and treatment effects were not significantly different. Drone captures in sticky traps showed a dose response in catch to 1, 3 or 10 gynes (virgin queens). Sticky traps baited with three gynes in a 5 × 5 array over 1 ha (four replicates), caught a mean of 7.39 (±0.88) drones per trap per day across the high density and control traps (n = 116), but there was no difference in the number of drones caught per central trap in the control and treatment plots (n = 4 per plot), demonstrating the limitations of our methods under extreme population pressure in such a mobile species. It is proposed that the gyne sex pheromone be identified and investigated for potential use in area-wide suppression, as it holds more promise as an attractant than the kairomones tested. http://www.zoobank.org/urn:lsid:zoobank.org:act:C0809A1F-87C2-431C-BA14-548F00D954F9 **KEYWORDS** *Vespula germanica; Vespula vulgaris;* drone; worker; sex pheromone; kairomone
###Pest control perceptions: comparing pesticides with next-generation control methods### **November 2022** In our part of the BioHeritage National Science Challenge we have been investigating the use of next-generation pest control technologies, with a focus on RNA interference to control invertebrate pests. In this presentation we will first describe RNA interference and then compare it with a widespread and common pesticide. What are the benefits and costs when you use that can of fly-spray under your kitchen bench, compared to what RNA interference could bring? At the same time, we investigate Māori views on novel technologies in pest management. What are the socio-cultural implications of RNAi? We explore methods and scenarios to engage a range of Māori views on these topics. To watch the webinar recording [CLICK HERE](https://youtu.be/M4SrGqkNBwo?si=TWLZQT8VBCcLZLPp&t=3)
**November 2022** Questions and answers for the "Pest control perceptions: comparing pesticides with next generation control methods" webinar.
PAPER: High-Quality Assemblies for Three Invasive Vespula
###High-Quality Assemblies for Three Invasive Social Wasps from the *Vespula* Genus### **October 2020** **Harrop T, Guhlin J, McLaughlin G, Permina E, Stockwell P, Gilligan J, Le Lec MF, Gruber MAM, Quinn O, Lovegrove M, Duncan EJ, Remnant EJ, Van Eeckhoven J, Graham B, Knapp RA, Langford KW, Kronenberg Z, Press MO, Eacker SM, Wilson-Rankin EE, Purcell J, Lester PJ, Dearden PK. 2020. [High-Quality Assemblies for Three Invasive Social Wasps from the *Vespula* Genus](https://academic.oup.com/g3journal/article-pdf/10/10/3479/37216514/g3journal3479.pdf). G3 Genes|Genomes|Genetics (Bethesda) 10(10): 3479-3488.** **ABSTRACT** We sequenced and annotated the genomes of the common wasp (*Vespula vulgaris*), German wasp (*Vespula germanica*), and the western yellowjacket (*Vespula pensylvanica*). Our chromosome-level *Vespula* assemblies each contain 176–179 Mb of total sequence assembled into 25 scaffolds, with 10–200 unanchored scaffolds, and 16,566–18,948 genes. We annotated gene sets relevant to the applied management of invasive wasp populations, including genes associated with spermatogenesis and development, pesticide resistance, olfactory receptors, immunity and venom. These genomes provide evidence for active DNA methylation in Vespidae and tandem duplications of venom genes. Our genomic resources will contribute to the development of next-generation control strategies, and monitoring potential resistance to chemical control. **KEYWORDS** *Vespula germanica, Vespula pensylvanica, Vespula vulgaris*, Hymenoptera, social insects, genomes
PAPER: Honeybee queen germline progenators
###Germline progenitors and oocyte production in the honeybee queen ovary### **September 2023** **Cullen G, Gilligan JB, Guhlin JG, Dearden PK 2023. [Germline progenitors and oocyte production in the honeybee queen ovary](https://academic.oup.com/genetics/article-pdf/225/1/iyad138/51343203/iyad138.pdf). Genetics 225(1).** **ABSTRACT** Understanding the reproduction of honeybee queens is crucial to support populations of this economically important insect. Here we examine the structure of the honeybee ovary to determine the nature of the germline progenitors in the ovary. Using a panel of marker genes that mark somatic or germline tissue in other insects we determine which cells in the honeybee ovary are somatic and which germline. We examine patterns of cell division and demonstrate that, unlike Drosophila, there is no evidence of single germline stem cells that provide the germline in honeybees. Germline progenitors are clustered in groups of 8 cells, joined by a polyfusome, and collections of these, in each ovariole, appear to maintain the germline during reproduction. We also show that these 8-cell clusters can divide and that their division occurs such that the numbers of germline progenitors are relatively constant over the reproductive life of queen honeybees. This information helps us to understand the diversity of structures in insect reproduction, and provide information to better support honeybee reproduction. **KEYWORDS** honeybees, ovary, cell division, reproductive rate, gene expression
PAPER: Gene drives for invasive wasp control
###Gene drives for invasive wasp control: Extinction is unlikely, with suppression dependent on dispersal and growth rates### **August 2023** **Lester PJ, O'Sullivan D, Perry GLW 2023. [Gene drives for invasive wasp control: Extinction is unlikely, with suppression dependent on dispersal and growth rates](https://doi.org/10.1002/eap.2912). Ecol Appl 33(7): e2912.** **ABSTRACT** Gene drives offer a potentially revolutionary method for pest control over large spatial extents. These genetic modifications spread deleterious variants through a population and have been proposed as methods for pest suppression or even eradication. We examined the influence of local dispersal, long-distance and/or human-mediated dispersal, and variation in population growth on the success of a gene drive for the control of invasive social wasps (*Vespula vulgaris*). Our simulations incorporated a spatially realistic environment containing variable habitat quality in New Zealand. Pest eradication was not observed, except in extreme and unrealistic scenarios of constant, widespread, and spatially intense releases of genetically modified individuals every year for decades. Instead, the regional persistence of genetically modified and wild-type wasps was predicted. Simulations using spatially homogeneous versus realistic landscapes (incorporating uninhabitable areas and dispersal barriers) showed little difference in overall population dynamics. Overall, little impact on wasp abundance was observed in the first 15 years after introduction. After 25 years, populations were suppressed to levels <95% of starting populations. Populations exhibited “chase dynamics” with population cycles in space, with local extinction occurring in some areas while wasps became abundant in others. Increasing the wasps' local dispersal distance increased the spatial and temporal variability of the occupied area and population suppression. Varying levels of human-associated long-distance dispersal had little effect on population dynamics. Increasing intrinsic population growth rates interacted with local dispersal to cause higher mean populations and substantially higher levels of variation in population suppression and the total amount of landscape occupied. Gene drives appear unlikely to cause a rapid and widespread extinction of this and probably other pests but could offer long-term and cost-effective methods of pest suppression. The predicted level of <95% pest suppression would substantially reduce the predation pressure and competitive interactions of this invasive wasp on native species. However, the predicted long-term persistence of genetically modified pests will influence the ethics and likelihood of using gene drives for pest control, especially given concerns that modified wasps would eventually be transported back to their home range. **KEYWORDS** CRISPR gene drives; dispersal; eradication; persistence; refuge; suppression
PAPER: RNA interference for suppressing *Varroa destructor*
###RNA interference as a next-generation control method for suppressing *Varroa destructor* reproduction in honey bee (*Apis mellifera*) hives### **May 2024** **McGruddy RA, Smeele ZE, Manley B, Masucci JD, Haywood J, Lester PJ. 2024. [RNA interference as a next-generation control method for suppressing Varroa destructor reproduction in honey bee (Apis mellifera) hives](https://scijournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ps.8193). Pest Manag Sci.** **ABSTRACT** **Background** The Varroa mite (*Varroa destructor*) is considered to be the greatest threat to apiculture worldwide. RNA interference (RNAi) using double-stranded RNA (dsRNA) as a gene silencing mechanism has emerged as a next-generation strategy for mite control. **Results** We explored the impact of a dsRNA biopesticide, named vadescana, designed to silence the calmodulin gene in *Varroa*, on mite fitness in mini-hives housed in a laboratory. Two dosages were tested: 2 g/L dsRNA and 8 g/L dsRNA. Vadescana appeared to have no effect on mite survival, however, mite fertility was substantially reduced. The majority of foundress mites exposed to vadescana failed to produce any offspring. No dose-dependent effect of vadescana was observed, as both the low and high doses inhibited mite reproduction equally well in the mini-hives and neither dose impacted pupal survival of the honey bee. Approximately 95% of bee pupae were alive at uncapping across all treatment groups. **Conclusion** These findings suggest that vadescana has significant potential as an effective alternative to conventional methods for *Varroa* control, with broader implications for the utilization of RNAi as a next-generation tool in the management of pest species. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. **KEYWORDS** biopesticide; RNA interference; *Apis mellifera*; honey bee; *Varroa destructor*; pest management
PAPER: Effects of DWV-dsRNA on bee viral loads
###Effects of Deformed Wing Virus-Targeting dsRNA on Viral Loads in Bees Parasitised and Non-Parasitised by *Varroa destructor*### **November 2023** **Smeele ZE, Baty JW, Lester PJ 2023. [Effects of Deformed Wing Virus-Targeting dsRNA on Viral Loads in Bees Parasitised and Non-Parasitised by *Varroa destructor*](https://doi.org/10.3390/v15112259). Viruses 15(11): 2259.** **ABSTRACT** The *Varroa destructor* mite is a devastating parasite of honey bees; however the negative effects of varroa parasitism are exacerbated by its role as an efficient vector of the honey bee pathogen, Deformed wing virus (DWV). While no direct treatment for DWV infection is available for beekeepers to use on their hives, RNA interference (RNAi) has been widely explored as a possible biopesticide approach for a range of pests and pathogens. This study tested the effectiveness of three DWV-specific dsRNA sequences to lower DWV loads and symptoms in honey bees reared from larvae in laboratory mini-hives containing bees and varroa. The effects of DWV-dsRNA treatment on bees parasitised and non-parasitised by varroa mites during development were investigated. Additionally, the impact of DWV-dsRNA on viral loads and gene expression in brood-parasitising mites was assessed using RNA-sequencing. Bees parasitised during development had significantly higher DWV levels compared to non-parasitised bees. However, DWV-dsRNA did not significantly reduce DWV loads or symptoms in mini-hive reared bees, possibly due to sequence divergence between the DWV variants present in bees and varroa and the specific DWV-dsRNA sequences used. *Varroa* mites from DWV-dsRNA treated mini-hives did not show evidence of an elevated RNAi response or significant difference in DWV levels. Overall, our findings show that RNAi is not always successful, and multiple factors including pathogen diversity and transmission route may impact its efficiency. **KEYWORDS** deformed wing virus; RNA interference; double-stranded RNA; *Varroa destructor*; biopesticide; RNA-seq
PAPER: Identifying causes of wasp eradication failure
###Improving wasp control by identifying likely causes of eradication failure### **May 2024** **Howse MWF, Reason A, Haywood J, Lester PJ 2024. [Improving wasp control by identifying likely causes of eradication failure](https://link.springer.com/content/pdf/10.1007/s10340-024-01788-9.pdf). Journal of Pest Science.** **ABSTRACT** Studying the efficacy of control methods is paramount to successful management of invasive pests and understanding why some colonies survive is important to improve management practices. Here, the bait Vespex® was used to control invasive wasps across 64 ha of forest in an invaded range near Hanmer Springs, New Zealand. Bait was applied across a standard 50 m by 300 m arrangement and made available for 3 days. Nest mortality rates after 19 days were 29.8%, although nearly all nests were affected with a median overall reduction in nest traffic of 96.5%. The results from logistic regression showed that, all else remaining equal, larger wasp nests, nests further from bait stations, and more isolated nests exhibited lower rates of mortality after baiting. Investigating the change in activity at surviving nests, the results from beta regression suggest that declines in nest traffic were less severe with increasing distance to the nearest bait, but more severe with increasing nest size. These results indicate that while smaller nests are at a higher risk of being killed by the bait, they may not encounter bait as regularly as larger nests. Bait uptake varied considerably across bait stations. Wasp nests were not randomly or uniformly distributed in space, and instead were aggregated across our treatment area, likely due to some aspects of environmental conditions. We suggest further research to be focused on developing an understanding of the drivers of wasp nest development and foraging behaviour, to produce a more flexible baiting procedure that will increase both baiting efficiency and efficacy. **KEYWORDS** Invasive species; Vespex; Pest management; Eradication; Toxic bait
PAPER: Sociality reduces probability of eradication success
###Sociality reduces the probability of eradication success of arthropod pests### **July 2023** **Howse MWF, Haywood J, Lester PJ. 2023. [Sociality reduces the probability of eradication success of arthropod pests](https://link.springer.com/content/pdf/10.1007/s00040-023-00921-8.pdf). Insectes Sociaux 70(3): 285-294.** **ABSTRACT** Social insects are successful and globally significant invaders. Compared to ongoing suppression, eradication is seen as an ideal solution and cost effective in the long term. The success of eradication attempts is not guaranteed and identifying key factors that could influence the success of such management programs would be beneficial. In this study, 239 eradication attempts were compiled and analysed to identify why eradication attempts fail, with a focus on how eusociality of the target species impacts eradication success. All else remaining constant, the odds of successful eradication were 79% lower when targeting social species compared to non-social insects. Eradication success was shown to increase when comparing more recent attempts to earlier ones but was found to decrease as the duration of the attempt went on. Eradication attempts that occurred on islands, and those that targeted species with a broader host range, were also associated with increased success. A review of cited reasons for eradication failure highlighted the importance of employing effective control treatments, management, and monitoring systems, as well as garnering adequate social and political support. This study indicates how social insects are particularly challenging to eradicate; it also notes the importance of considering both logistical and biological aspects of any eradication, before initiating eradication attempts. **KEYWORDS** Pest management; Invasive species; Logistic regression; Management success
PAPER: Biotechnologies in pest wasp control
###Biotechnologies in pest wasp control: taking the sting out of pest management for Māori businesses### **August 2019** **Palmer S, Mercier OR 2020. [Biotechnologies in pest wasp control: taking the sting out of pest management for Māori businesses?](https://www.tandfonline.com/doi/epdf/10.1080/14636778.2020.1799344?needAccess=true) New Genetics and Society 40(2): 155-177.** **ABSTRACT** In Aotearoa New Zealand, the government’s ambitious target of becoming “predator-free” by 2050 has reignited public discussion on biotechnologies. The disproportionate abundance of German and common wasps in New Zealand disrupts native biodiversity and costs $133 million annually to the economy, making exotic wasps an expedient trial pest species for novel biotechnological controls. Māori businesses occupy primary industries said to benefit from wasp control. A Māori-centered mixed-method study gauged the perceptions of eight Māori businesses about the potential use of five specific new biotechnological controls in pest management. Participants raised concerns about risk and side effects; called for further information and a reconfiguring of how information is presented; reflected on previous pest challenges; and took positions in reference to Māori customary concepts. While all agree that doing nothing is not an option, careful, informed deliberation is required on whether and how best to move forward with these new biotechnological controls. **KEYWORDS** Māori business; biotechnology; pest control; wasps; New Zealand; biodiversity and conservation
PAPER: CRISPR gene drive to control wasps
###The potential for a CRISPR gene drive to eradicate or suppress globally invasive social wasps### **October 2020** **Lester PJ, Bulgarella M, Baty JW, Dearden PK, Guhlin J, Kean JM 2020. The potential for a CRISPR gene drive to eradicate or suppress globally invasive social wasps. Sci Rep 10(1): 12398.** **ABSTRACT** CRISPR gene drives have potential for widespread and cost-efficient pest control, but are highly controversial. We examined a potential gene drive targeting spermatogenesis to control the invasive common wasp (Vespula vulgaris) in New Zealand. Vespula wasps are haplodiploid. Their life cycle makes gene drive production challenging, as nests are initiated by single fertilized queens in spring followed by several cohorts of sterile female workers and the production of reproductives in autumn. We show that different spermatogenesis genes have different levels of variation between introduced and native ranges, enabling a potential ‘precision drive’ that could target the reduced genetic diversity and genotypes within the invaded range. In vitro testing showed guide-RNA target specificity and efficacy that was dependent on the gene target within Vespula, but no cross-reactivity in other Hymenoptera. Mathematical modelling incorporating the genetic and life history traits of Vespula wasps identified characteristics for a male sterility drive to achieve population control. There was a trade-of between drive infiltration and impact: a drive causing complete male sterility would not spread, while partial sterility could be effective in limiting population size if the homing rate is high. Our results indicate that gene drives may offer viable suppression for wasps and other haplodiploid pests. **KEYWORDS** CRISPR gene drive; pest control; invasive species; social wasps; spermatogenesis; genetic diversity; precision drive; male sterility; population control; haplodiploid pests
PAPER: Towards rangatiratanga in pest management? Māori perspectives and frameworks on novel biotechnologies in conservation
###Towards rangatiratanga in pest management? Māori perspectives and frameworks on novel biotechnologies in conservation### **September 2020** **Palmer S, Ripeka Mercier O, King-Hunt A 2021. [Towards rangatiratanga in pest management? Māori perspectives and frameworks on novel biotechnologies in conservation](https://www.publish.csiro.au/pc/pdf/PC20014). Pacific Conservation Biology 27(4)** **ABSTRACT** We gathered Māori perspectives on novel biotechnological controls for pest wasps through three distinct studies. Study participants included tertiary students, businesses, and spiritual or religiously affiliated groups. All participants drew from their identities as Māori people to help identify their position on these issues. Their perspectives on issues of consent and Social Licence suggest a preference for processes based upon rangatiratanga. Participant perspectives were also organised according to a take utu ea decision-making framework. **KEYWORDS** consent, conservation tools, culture, environmental management, genetic modification, indigenous communities, invertebrates, New Zealand, Social License.
PAPER: Nasonia pair-rule gene regulatory network
###The *Nasonia* pair-rule gene regulatory network retains its function over 300 million years of evolution### **March 2022** **Warburton B, Eason C, Fisher P, Hancox N, Hopkins B, Nugent G, Ogilvie S, Prowse TAA, Ross J, Cowan PE. 2021. [Alternatives for mammal pest control in New Zealand in the context of concerns about 1080 toxicant (sodium fluoroacetate)](https://journals.biologists.com/dev/article-pdf/149/5/dev199632/2135760/dev199632.pdf). New Zealand Journal of Zoology: 1-43.** **ABSTRACT** Insect segmentation is a well-studied and tractable system with which to investigate the genetic regulation of development. Though insects segment their germband using a variety of methods, modelling work implies that a single gene regulatory network can underpin the two main types of insect segmentation. This means limited genetic changes are required to explain significant differences in segmentation mode between different insects. This idea needs to be tested in a wider variety of species, and the nature of the gene regulatory network (GRN) underlying this model has not been tested. Some insects, e.g. *Nasonia vitripennis* and *Apis mellifera* segment progressively, a pattern not examined in previous studies of this segmentation model, producing stripes at different times progressively through the embryo, but not from a segment addition zone. Here, we aim to understand the GRNs patterning *Nasonia* using a simulation-based approach. We found that an existing model of Drosophila segmentation ( Clark, 2017) can be used to recapitulate the progressive segmentation of *Nasonia*, if provided with altered inputs in the form of expression of the timer genes Nv-caudal and Nv-odd paired. We predict limited topological changes to the pair-rule network and show, by RNAi knockdown, that Nv-odd paired is required for morphological segmentation. Together this implies that very limited changes to the Drosophila network are required to simulate *Nasonia* segmentation, despite significant differences in segmentation modes, implying that *Nasonia* use a very similar version of an ancestral GRN used by *Drosophila*, which must therefore have been conserved for at least 300 million years. **KEYWORDS** Gene regulatory network, Pair-rule genes, Patterning, Segmentation, *Nasonia*
BRIEF: Safe effective and targeted tools
###Safe, effective, and highly targeted tools for pest control ### **March 2024** A new method to control the varroa parasite and improve honey bee health For decades we have relied on broad-spectrum synthetic chemicals to control pests. These can be harmful to the environment, other organisms, and sometimes even the species we are trying to help.
REPORT: Genetic Modification Pest Control Perspectives
###Charting Perspectives of Genetic Modification for Pest Control in Aotearoa New Zealand### **March 2023** **Hemmerling L, Horowitz J, Kanli R, MacDonald L. 2023. Charting Perspectives of Genetic Modification for Pest Control in Aotearoa New Zealand, Worcester Polytechnic Insitute.** **ABSTRACT** Aotearoa New Zealand focuses on pest control to preserve the country’s fragile biodiversity. Genetic modification presents a potential strategy for pest control, but it raises complex ethical, social, and political viewpoints. We collaborated with Dr. Ocean Mercier to chart researchers’ and environmentalists’ perspectives on gene-based pest control, which furthers her goal of understanding Aotearoa’s opinions on novel biotechnologies for conservation. Through the Q-Method, we organized shared views on gene-based pest control, which will help Aotearoa reach its goal of being a predator-free country.
THESIS: Māori perceptions of wasp eradication controls
###Novel biotechnological controls for social wasp eradication: Exploring religious and spiritual Māori perceptions using a Q-Method and kaupapa Māori methodology### **February 2023** **King Hunt A. 2023. [Novel biotechnological controls for social wasp eradication: Exploring religious and spiritual Māori perceptions using a Q-Method and kaupapa Māori methodology.](https://openaccess.wgtn.ac.nz/ndownloader/files/39429472) A thesis submitted for the degree of Master of Arts in Māori Studies. Victoria University of Wellington. p. 254** **ABSTRACT** This thesis explores the perceptions religious and/or spiritual Māori have about five biotechnological controls proposed for the eradication of the *Vespula germanica* (German) and *Vespula vulgaris* (common) wasp-species in Aotearoa New Zealand. As part of the National Science Challenge - BioHeritage project, scientists are currently conducting research into the wasp biotechnological controls (WBC), which include: gene drives, RNA interference (RNAi), Trojan female, Trojan mite, and an artificial pheromone. The two primary objectives of this research are, firstly, using Likert scale ranking to determine which, if any, of the WBC religious/spiritual Māori would position as a feasible method of wasp control; and secondly, using Q-method to seek out the shared and divergent social, cultural, spiritual, and religious contextual views the participants have about WBC more generally. Research was conducted among 16 participants using a ‘quali-quantological’ mixed-methods approach, comprising a Māori-centred research practice using both Likert scale and Q Method ranking activities. Likert findings position the pheromone lure is the most favoured WBC and contrastingly, RNAi is the least favoured. Additionally, Q Method factor analysis distinguished three ‘factors’ - which describe the distinct views held by participant sub-groups - which are: 1) those who view the use of WBC as plausible, 2) those who see them as problematic, and 3) those who consider them implausible. **KEYWORDS** Wasp biotechnological controls; Māori; Religious; Spiritual
###Healthy bee, sick bee: the influence of parasites, pathogens, predators and pesticides on honey bees### **2022** **Lester PJ. 2022. Healthy bee, sick bee: the influence of parasites, pathogens, predators and pesticides on honey bees. Victoria University Press. **ABSTRACT** In this book, entomologist Phil Lester explores the wonderfully complex and sometimes brutally efficient life history of honey bees, and the problems they face in New Zealand and around the globe. What causes a beehive to collapse? Are pesticides as big a problem as they appear? What can we do to improve the health of our honey bees? With intelligence, insight and entomologist jokes, Healthy Bee, Sick Bee tells the story of this much-loved little insect and offers new ways of thinking about how to ensure they will stick around in the future.
WEBINAR: C&A4 Controlling Invasive invertebrates
###Online quick-fire presentation from Crazy & Ambitious 4: Controlling Invasive invertebrates - Day 1### **April 2024** Online quick-fire presentation from Crazy & Ambitious 4: Controlling Invasive invertebrates, with Phil Lester and Ocean Mercier, Victoria University of Wellington.
###Online presentation from Crazy & Ambitious 4: Controlling Invasive invertebrates - Day 2### **April 2024** Online presentation from Crazy & Ambitious 4: Controlling Invasive invertebrates, with Phil Lester and Ocean Mercier, Victoria University of Wellington
WEBINAR: C&A4 Alternative varroa control products
###Online presentation from Crazy & Ambitious 4: The need for alternative control products for varroa### **April 2024** Online presentation from Crazy & Ambitious 4: The need for alternative control products for varroa, with David Wiessing.
###Anuhe Tawatawa, e!### **June 2024** **Palmer S & Mercier OR.; Kerrison L. (illustrator). 2024. Anuhe Tawatawa, e! Ngā Koiora Tuku Iho - New Zealand's Biological Heritage National Science Challenge. p 24.** **ABSTRACT** Anuhe, tawatawa e! (Anuhe, mottled like the skin of a mackerel) - he pukapuka tēnei e whakamānawa ana i ngā mahi a Symon (Ngāi Te Rangi) rāua ko Ocean (Ngāti Porou) - he kairangahau kaupapa taiao ki Ngā Koiora Tuku Iho. Kua tuhi i ngā kōrero o te pukapuka nei i te mita o Ngāti Porou nā runga i ngā runga i ngā hononga whakapapa o Ocean ki ngā moka whenua me ngā tai moana o Te Tairāwhiti. Anuhe, tawatawa e! (Caterpillar, mottled like the skin of a mackerel!) - a book inspired by the work of Symon (Ngāi Te Rangi) and Ocean (Ngāti Porou) - environmental researchers at Ngā Koiora Tuku Iho. The story in this book uses the mita (pronunciation/dialect) of Ngāti Porou in recognition of the relationship that Ocean has with the land and seas of Te Tairāwhiti. This is one of six books, written in te reo Māori, in a series about nature and conservation efforts around New Zealand produced through the NZ Biological Heritage National Science Challenge.