Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Managing Invasives

Research activity 2015/16 Key Achievements Core Funding Investment ($M excl GST)
  2015/16 (planned) 2015/16 (actual)
Managing Invasives $3.55 $3.90
End users: DOC; MfE; MPI; MFAT; regional councils; non governmental conservation organisations (NGOs); community conservation/restoration groups; local government; Environment Court; Fonterra; researchers; Māori; Tūhoe Tuawhenua Trust; consulting firms; community conservation groups; landowners/managers; QEII National Trust; philanthropists; Kiwis for kiwi; Aotearoa Foundation; National Wetland Trust.
Beating Weeds – Outcome 1 and 4 $1.28 $1.38
  • Performed an ex-post economic analysis of NZ’s biological control programme against ragwort and calculated that the ragwort flea beetle (released 1983) is currently saving the dairy sector NZ$44 million/yr in reduced weed control costs. Ragwort biocontrol in NZ began in the 1920s, and a net present value (NPV) analysis gave a 14:1 benefit:cost ratio. In NZ, the flea beetle was rejected as a biocontrol agent in 1933 on anecdotal evidence of its low impact on ragwort. This poor decision cost the dairy industry an estimated NZ$8.6 billion (NPV) from 1945 to 1999: an early investment in scientific trials, rather than relying on anecdotal evidence, would have demonstrated the impact of the flea beetle, and avoided these huge accumulated losses.
  • Discovered that the potentially plant-pathogenic bacterium Candidatus Liberibacter europaeus (leu) is detectable in broom seed. Furthermore, broom seedlings can develop high levels of leu in the absence of broom psyllids, which were previously thought to be obligate vectors of leu. This raises the possibility that leu was originally introduced into NZ in broom seed, and was not a result of unknowingly importing contaminated broom psyllids for biocontrol in 1983. Testing of broom seed from Europe and New Zealand is needed to shed more light on this question. The transmission of a Ca. Liberibacter via contaminated seed raises biosecurity issues for seed exports/imports.
  • Successfully gained approval for new biocontrol agents to be released against field horsetail and tutsan.
Reducing Mammal Impacts – Outcome 1 and 4 $1.31 $1.30
  • Working with Hawke’s Bay Regional Council:
    • demonstrated the benefits of broad-scale mammal pest control for native fauna in farmland (Poutiri Ao ō Tāne)
    • provided an online tool for managers to predict efficacy of various trap configurations and trap check intervals
    • evaluated the importance of community and rural landowner attitudes to implementation of the Cape to City (C2C) initiative
    • determined toxoplasmosis levels in feral cats and sheep o produced a map identifying where possum control needs to be concentrated and where it can be delayed in the C2C planning
    • published synthesis of relationships between invasive mammal abundance and impacts on native biodiversity used as a framework for setting control targets in C2C.
  • Analysed nationwide data from published and unpublished studies of possum control (either ground-based control or using aerially-delivered baits) to demonstrate for the first time that there are unequivocal quantifiable benefits for indigenous vegetation, birds and invertebrates.
  • Predicted the extent of the 2016 mega-mast, using a model relating summer temperatures to post-mast outbreaks of rodents in beech forest. DOC used this for the second stage of the ‘Battle for Our Birds’ campaign; cost $20.7 million.
  • Used the latest climate projections from NIWA to show that there are no clear predicted effects of climate change on the frequency of mega-masts due to high levels of uncertainty in climate projections.
  • Demonstrated the value of a new method that can be used by DOC to monitor the impacts of rodents and possums on invertebrate communities in forest canopies; this is based on quantification of insect frass collected in standard seedfall traps.
Mammal Control Tools – Outcome 1 and 4 $0.31 $0.38
  • Cemented our partnership with Animal Control Products to commercialise LR’s rat-selective compound. Chemistry synthesis has been adapted to produce a flowable powder form that allows easy incorporation into a bait matrix. Testing on Norway rats has been successful. Interest in the compound has grown from international sources (Chevron (AU), Rentokil (UK), ZAPI (IT) and we are in discussions with Indonesia to trial it in palm oil plantations and rice fields.
  • Co-funded work on ‘chemical camouflage’ against mammalian pests, with significant progress identifying chemical constituents of bird odour as predator attractants.
TB Freedom – Outcome 4 $0.45 $0.47
  • Implemented large-scale (up to 80 000 ha) demonstrations of a quicker and cheaper approach to declaring TB freedom in possums.
  • Identified how to best allocate funding between TB surveillance and possum control to minimise total expected costs, using decision-theory bio-economic modelling.
  • Contributed significantly (through national-scale modelling of alternative strategic scenarios and associated seconded policy advice) to a decision by agricultural industries and government to adopt national eradication as the goal of TB management.
  • Worked closely with OSPRI to make our research findings widely available and easily understood through production of 11 web-based factsheets and 8 short articles.
Strategic Developments – Outcomes 1 and 4 $0.20 $0.37
  • Developed a new ‘proof of freedom’ statistical framework to guide the eradication of insect incursions (demonstrated through the case study of Argentine ant eradication from Kawau Island).
  • Identified a robust framework for the pre-emptive biological control of arthropod pests.
  • Co-funded successful Nation of Curious Minds ‘Mould Scene Investigators’, working with school children to improve home health.
  • Published work indicating that avian malaria is driving frequency changes in immune genes in native New Zealand birds, implying population-scale impacts.