Biocontrol introduction
Target pest: Hypericum androsaemum (Malpighiales: Hypericaceae), tutsan
Agent introduced: Chrysolina abchasica (Coleoptera: Chrysomelidae), tutsan leaf beetle
Imported:
2014
Import source:
Georgia, Europe
Import notes:
Landcare Research (2015h) - has been in containment at Lincoln since 2014 for evaluation.
Released:
2017
Release details:
Landcare Research (2017b) - first release February 2017 at Tauramunui (King Country, central North Island). Only released at one site initially as difficult to rear in captivity.
Landcare Research (2018h) - 7 releases made in the year Sep 2017 - Aug 2018.
Landcare Research (2019d) - the beetle has been released at about a dozen sites.
Landcare Research (2019j) - 5 releases made in the year Sep 2018 - Aug 2019.
Landcare Research (2020h) - 3 releases made in the year Sep 2019 - Aug 2020.
Landcare Research (2021e) - 7 releases made in the year Sep 2020 - Aug 2021.
Establishment:
Landcare Research (2019i) - establishment success unknown.
Landcare Research (2021f) - establishment success unknown but some promising signs seen.
Impacts on non-targets:
Hill (2015b) - tutsan belongs to the family Hypericaceae. Hypericum is the only genus of this family present in New Zealand; there are four native species. In host plant tests carried out by Landcare Research there was no larval survival on hosts outside of Hypericaceae. Chrysolina abchasica laid some eggs on two of the three native species tested; of eggs that hatched on these native species 9% completed development on H. pusillum and 12% on H. rubicundulum, compared to 82% on tutsan. Hypericum pusillum and H. rubicundulum can therefore be considered fundamental hosts. However, few eggs were laid, and few larvae completed development on the natives compared with tutsan; they therefore appear to be barely adequate hosts for C. abchasica, and unlikely to support thriving populations. It is predicted they will have trivial impacts on these species. Impacts on valued non-native Hypericum species are likely to be low as these species are not widely grown as ornamentals and populations capable of causing noticeable damage on these species are unlikely.
Landcare Research (2015h) - host testing in containment: while the natives Hypericum pusillum and H. rubicundulum can be considered fundamental hosts, most adults produced by these plants died soon after emergence and significant damage to these species in the field is not expected. Paynter et al. (2015) - using research quantifying the relative performance of agents in lab trials on a test plant versus the target weed it was concluded the risk of the beetle attacking the two native Hypericum species in the field is low.
EPA Applications:
EPA (2016a) - 20 Nov 2015: application by the Tutsan Action Group to import and release the moth, Lathronympha strigana, and the beetle, Chrysolina abchasica, as biocontrol agents for the weed tutsan, Hypericum androsaemum. EPA Application APP202663, approved without controls 18 May 2016.
References
EPA (2016a). EPA application APP202663: to introduce the moth Lathronympha strigana and the leaf beetle Chrysolina abchasica as biological control agents for the weed tutsan (Hypericum androsaemum). Environmental Protection Authority website https://www.epa.govt.nz/database-search/hsno-application-register/view/APP202663
Hill R. (2015b). EPA application [APP202663] to obtain approval to release new organisms [Chrysolina abchasica and Lathronympha strigana]. Environmental Protection Authority website https://www.epa.govt.nz/assets/FileAPI/hsno-ar/APP202663/dec2058e97/APP202663-APP202663-Application-FINAL-2015-11-20.pdf
Landcare Research (2015h). Tutsan agents imminent Weed Biocontrol: What's New? 74: 5 http://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-74
Landcare Research (2017b). Tutsan agents released. Weed Biocontrol: What's New? 80: 3 http://www.landcareresearch.co.nz/__data/assets/pdf_file/0013/141133/Issue-80.pdf
Landcare Research (2018h). Biocontrol agents released in 2017/18. Weed Biocontrol: What's New? 85, August 2018 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-85/biocontrol-agents-released-in-201718
Landcare Research (2019d). Final phase for tutsan project. Weed Biocontrol: What's New? 88, May 2019. https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/weed-biocontrol-issue-88/final-phase-for-tutsan-project
Landcare Research (2019i). Who's who in biological control of weeds? Weed Biocontrol: What's New? 89, August 2019 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/weed-biocontrol-issue-89/whos-who-in-biological-control-of-weeds
Landcare Research (2019j). Biocontrol agents released in 2018/19. Weed Biocontrol: What's New? 89, August 2019 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/weed-biocontrol-issue-89/biocontrol-agents-released-in-201819
Landcare Research (2020h). Further reading and agents released table. Weed Biocontrol: What's New? 93, Aug 2020. https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/further-reading-and-agents-released-table/
Landcare Research (2021e). Further reading and agents released. Weed Biocontrol: What's New? 97, August 2021 https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/further-reading
Landcare Research (2021f). Who's who in biological control of weeds? Weed Biocontrol: What's New? 97, August 2021 https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/whos-who-in-biological-control-of-weeds
Paynter QE, Fowler SV, Gourlay AH, Peterson PG, Smith LA and Winks CJ (2015). Relative performance on test and target plants in laboratory tests predicts the risk of non-target attack in the field for arthropod weed biocontrol agents. Biological Control 80: 133-142 https://doi.org/10.1016/j.biocontrol.2014.10.007
