Biocontrol introduction
Target pest: Hieracium spp. (Asterales: Asteraceae), hawkweed
Agent introduced: Cheilosia psilophthalma (Diptera: Syrphidae), hieracium root hover fly
Imported:
Late 1990s, 1998, 2001
Import source:
Switzerland
Import notes:
Smith (2007a) - several shipments were imported by Landcare Research, in conjunction with the Hieracium Control Trust, in the late 1990s for testing.
Release details:
Smith (2007a) - released at limited sites as difficult to rear.
Establishment:
Landcare Research (2014c) - establishment success unknown.
Landcare Research (2020e) - surveys in 2020 at release sites of hieracium biocontrol agents - Canterbury and Otago in the South Island (Marlborough release sites were not visited) and on the Central Plateau of the North Island - did not recover any C. psilophthalma and it is presumed to have failed to establish, which is not surprising given the small numbers released.
Impacts on non-targets:
Hieracium Control Trust (2000) - host range tests were completed on 66 test plant species comprising 9 species from the genus Hieracium, 29 species in the family Asteraceae, including the closest relatives to Hieracium among native New Zealand plants, and 28 species from an additional 25 families of plants. Oviposition and larval development tests were carried out in Switzerland, or under insect containment conditions in New Zealand for those plants that could not be grown in Switzerland. No eggs were laid on plants other than Hieracium species, and no larvae survived on any plants other than Hieracium species. There are no native plants in the genus Hieracium; the genus is represented in New Zealand by weedy species introduced from Europe. The host range tests indicate the likelihood that any non-target species will be negatively affected is very low.
EPA Applications:
EPA (2001) - 17 Nov 2000: application by the Hieracium Control Trust to import for release the insects Macrolabis pilosellae (Binnie 1878), Cheilosia urbana (Meigen 1822) and Cheilosia psilophthalma (Becker 1894) for the purpose of biological control of hawkweeds, Hieracium spp. EPA Application #NOR00001, approved without controls 27 Jun 2001.
References
Auckland Regional Council (). The Land 99 http://greensite.arc.govt.nz/library/:70039-2.pdf
EPA (2001). EPA application NOR00001: to import for release the insects Macrolabis pilosellae (Binnie 1878), Cheilosia urbana Meigen and Cheilosia psilophthalma (Becker 1894) for the purpose of biological control of hawkweeds, Hieracium spp. Environmental Protection Authority website https://www.epa.govt.nz/database-search/hsno-application-register/view/NOR00001
Hieracium Control Trust (2000). Application to EPA (NOR00001) to import for release the insects Macrolabis pilosellae (Binnie 1878), Cheilosia urbana Meigen and Cheilosia psilophthalma (Becker 1894) for the purpose of biological control of hawkweeds, Hieracium spp. Environmental Protection Authority website https://www.epa.govt.nz/assets/FileAPI/hsno-ar/NOR00001/6b046d0b38/Application-NOR00001.pdf
Landcare Research (2014c). Who's who in biocontrol of weeds? What's new in biological control of weeds? 69: 10-11 http://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-69
Landcare Research (2020e). Hieracium biocontrol – 20 years on. Weed Biocontrol: What's New? 93, Aug 2020 https://www.landcareresearch.co.nz/publications/weed-biocontrol/weed-biocontrol-articles/hieracium-biocontrol-20-years-on/
Smith L (2007a). Hieracium Hover Fies. In The Biological Control of Weeds Book (Landcare Research) http://www.landcareresearch.co.nz/research/biocons/weeds/book/documents/Hieracium_Hover_Flies.pdf
