241 likes | 314 Views
Biocontrol of Parthenium. Monitoring and Evaluation. K. Dhileepan Segun Osunkoya Rachel McFadyen. Invasive Plant Science Biosecurity Queensland Department of Agriculture, Fisheries & Forestry Ecosciences Precinct Brisbane, Australia. Biological control. Initiated in 1974
E N D
Biocontrol of Parthenium Monitoring and Evaluation K. Dhileepan Segun Osunkoya Rachel McFadyen Invasive Plant Science Biosecurity Queensland Department of Agriculture, Fisheries & Forestry Ecosciences Precinct Brisbane, Australia
Biological control • Initiated in 1974 • Native range surveys (1976-1996) • 9 insects + 2 fungi introduced • 8 insects + 2 fungi established • 5 agents widespread & effective • Vary seasonally and temporally NQ CQ SEQ
Smicronyx weevil • Zygogramma beetle • Epiblema moth • Stobaera bug • Conotrachelus weevil • Winter rust • Summer rust • Bucculatrix moth • Listronotus weevil • Carmenta moth
History • 1994 • 2004 • 1974 • 2014 • 1984 • 1996 • 1976 • Native range survey • 1999 • 1979 • Host specificity tests • 1980 • 2004 • Field release • 2014 • 1980 • Monitoring • 1996 • 2000 • Evaluation
LAG-TIME: Introduction and establishment • Smicronyx • Summer rust • Zygogramma • 1994 • 2004 • 1974 • 2014 • 1984 • Carmenta • Winter rust • Epiblema & Listronotus • Conotrachelus • Evaluation
Monitoring & Evaluation • Smicronyx weevil - yet to be evaluated • MONITORING • Establishment and spread • Abundance and damage • Individual plant level • Population level • Local and regional scale • EVALUATION • Baseline (pre-release) data • Impact assessment • Plant population level • Ecosystem response • Economic assessment
Monitoring & evaluation – why? • Measure the success/failure • Estimate economic benefits (if successful) • Why biocontrol failed (if failed) • Satisfy Government/funding bodies • Increase public profile • Attract funding for future research • Sense of achievement and satisfaction
Monitoring • North Qld (3 sites) • Central Qld (12 -16 sites) • Since 2004 (annual survey) • Parthenium incidence • Agent abundance • Pasture cover • South-east Qld (2 sites) • Commenced in 2014 • Monthly sampling • Agent introduction • Seed bank • Stomphastis sp. nova
Monitoring • Summer rust Incidence & abundance across 19 sites since 2004
Evaluation • Before & after-release • Simulation experiments • Performance vs. damage • Exclusion trials • Long-term changes • target weed population • beneficial plant communities • seed-bank dynamics • temporal and spatial changes • Stomphastis sp. nova
Evaluation - difficulties • Different methods • All not suitable for all agents • All methods have deficiencies • Labor intensive and expensive • Extensive & intensive studies required • Dependent of community help • At the mercy of weather conditions • Erratic (but realistic) results
Before & after release • Variable establishment times for different agents • Variable time taken for the agent to become abundant • long-term pre-release data often not available • Long-term impact studies not usually followed • 1996 • 1998
Simulation experiments • Glasshouse & field experiments • Evaluation at plant level only • Not always reflect field situation • Bench mark for field evaluation • Other biotic factors excluded • Multi-location trial is beneficial • Zygogramma beetle • Epiblema moth • Listronotus weevil • Summer rust • Conotrachelus weevil C = control; R = rosette; PF = pre-flowering; F = flowering
Damage levels vs. plant performance • Suitable to evaluate at individual plant level • Not suitable when damage level is dependent on plant vigor • Difficult to relate with changes in weed population C = control; R = rosette; PF = pre-flowering; F = flowering; Ex = excluded; Es = escaped
Biocontrol exclusion • Field cage • affect plant vigor • influence the agent performance • long-term maintenance difficult • Not useful for pathogens • Pesticides • residue problem • labor intensive and expensive • affected by weather condition
Economic benefit • Buffel Grass • Blue Grass • Increase in feed (kg/ha) • 22.44 • 32.54 • Increase in cattle (hd/ha) • 0.0021 • 0.0020 • Economic benefits ($/ha) • $0.82 • $0.78 • Cost benefit = $ 2.09 • (based on 2000 value)
Before commencing evaluation • Late 1980s Do we need pre-release data? Should we study seed-bank? If so, for how long? How long to evaluate? 20 years good - 5 year intervals Snap-shots over time When to start evaluation? Start now!!
Where to start!Release efforts in climatically favourable areas (CLIMEX models). • Seed bank (once in 3-5 years) + above-ground studies • In Africa study areas more likely to be cropping (disturbed) areas • Opportunity to compare cropping & non-cropping areas • Beneficial to establish ‘refuge’ for biocontrol agents • Performance across low and high ‘altitudes’ • In Australia and India Z. bicolorata outbreaks declined over time. • Need to check if this will happen in Africa as well.
Good luck • We would be happy to help in your monitoring and evaluation studies