Biocontrol Flashcards
What can broad-spectrum pesticides be harmful to ?
Non-Target insects
Other wildlife
Farm worker health
Consumer health
Why is resistance to pesticides occurring ?
Higher application rates
New pesticides
Use more to kill resistant species- ‘pesticide treadmill’
What are the issues with global travel and pests ?
Exotic pests are moving around the world
natural enemies are not in the new habitat
What is the benefit of biocontrol ?
Long term, sustainable and relatively inexpensive
list the 3 types of organisms which require biocontrol programmes
Weeds (knotweed)
Insects (spruce bark beetle)
Vertebrates (rabbits)
What is interesting about Japanese knot weed ?
It is a clone, largest female in the world
Can be Dioecious, but only female in the UK
List the 5 main types of biocontrol agent.
Parasitoids Viruses Bacteria Insect herbivores Insect predators
Give a bad example of biological control agents
Cane toad introduced wherever sugar cane was grown
Became a huge pest
Instead had to introduce toad control (mongoose, stoat, predatory ants)
List the 3 main types of biocontrol
Classical biological control
Augmentation biological control (Egg parastioid)
Conservation biological control
What is classical bio control ?
Introduction and establishment of an exotic natural enemy for control of an exotic pest
(reunite pest with enemy)
Does classical biocontrol always work ?
Sometimes, but not always
Give the statistics of biocontrol success for arthropods
25% of agents will become established
of these 49% will control the pest
Give the statistics of biocontrol success for weeds
30% will be controlled by the natural enemy
List the 5 steps in a classical biological control programme
Choose target weed Foreign exploration for enemy Host range testing Field release Evaluation
Give the 2 non target effects of biocontrol.
Direct and Indirect effects
Describe the data on non target interactions in biocontrol
Only a handful of studies
Huge amount of anecdotal info
Huge amount of opinion
No data at the level of whole herbivore communities
What is the solution for monitoring non target interactions of biocontrol agents ?
Use of a web of species interactions rather than a simple unbranched food chain.
Is biocontrol safer than its alternatives on the current regulations ?
Yes, it is as safe or safer
and is often the only option left.
What is potentially damaging to biocontrol ?
The controversy surrounding it
Give an example of successful biocontrol
Giant salvina in Australia, a weed was controlled by the Weevil
Caused dramatic reduction
