Biological Control and Aquatic Insects

Question 1

Biological Control

Answer 1

The intentional use of higher trophic levels to reduce pest densities to limit damage

Question 2

Advantages of Biological Control

Answer 2

-Economical
-Durable
-No chemical hazards
-Integrates well with other pest control methods (except pesticides)
-Highly pest specific

Question 3

Disadvantages of Biological Control

Answer 3

-Numerous projects have not succeeded or were not effective
-Requires some level of pest population
-May endanger native organisms
-Time consuming

Question 4

Population Limitation

Answer 4

-Chemical control
-Multiple applications
-Fails without re-application

Question 5

Population Regulation

Answer 5

-Biological control
-Self-sustaining
-Effects are population size dependent

Question 6

Why aren’t pests naturally regulated?

Answer 6

“Enemy release”
-Pesticides knock back natural enemies
-Plant domestication
-Monoculture in landscape

Question 7

What are the effects of plant domestication?

Answer 7

Trade-off between wanted traits (i.e. taste, size) to survival traits (i.e. disease resistence)

Question 8

Pest mutualisms

Answer 8

Pests facilitating pests

Question 9

Example of pest mutalisms

Answer 9

Ant/hemiptera mutualism
1) Ants feed on honeydew producers-which are sap sucking pests
2) Ants get suguary food-hemiptera get protection
3) Ants intimidate or kill natural enemies

Question 10

Omnivory

Answer 10

Animals that feed from 2 or more trophic levels

Question 11

Why is omnivory important for biological control?

Answer 11

1) Omnivores can weather periods of low prey availability better than strict predators
2) Increases predator survival, reproduction, or immigration
3) EX: Big eyed bugs and lima bean pods

Question 12

What is landscape diversification associated with?

Answer 12

1) Improved pest management
2) Increased natural enemy diversity and abundance
3) EX: Higher plant diversity was associated with better supression of the soybean aphid

Question 13

How can plant diversity disrupt pest establishment or activity?

Answer 13

1) Trap crops
2) Repellant plants
3) Mask crop
4) Barrier planting (also works for disease management)

Question 14

What steps are taken to find a classical biological control agent?

Answer 14

1) Determine geographic orgin of pest
2) Search for pest and its natural enemies
3) Test prospective natural enemies for efficacy against pest
4) Develop procedures to rear prospective natural enemies
5) Test for safety against useful native insects
6) Quarantine to avoid pathogens or parasites
7) Release

Question 15

What are some challenges to living underwater?

Answer 15

1) Respiration (not much oxygen underwater)
2) Flow (lack of, or too much!)
3) Surface tension

Question 16

What are some adaptations to living underwater?

Answer 16

1) Aerial respriation (ex. mosquito larvae)
2) Physical gills
3) Gills-closed system
4) Closed tracheal system
5) Morphological adaptations

Question 17

Did the evolution of aquatic insects happen one or many times?

Answer 17

Many