1. DETERMINING MITE LEVELS

2. READING THE RESEARCH
Oogenesis of Varroa mites remains arrested in the previtellogenic stage during the phoretic phase on the adult bees and is activated shortly after the invasion of a brood cell.

3. Outline Introduction Topic: Determining Varroa Mite Levels What is IPM
Basic Knowledge of Mites
Why Test?
Which Test(s) to Use?
When to Test?
How to Test?
What are Thresholds in IPM
When to Treat?
IPM treatment strategies

4. IPM – Integrated Pest Management Dewey M. Caron
I=INTEGRATED – ideally use of more than pesticide
chemical control
P=PEST – mites sure but applicable to any of the 3 P’s
M=MANAGEMENT – as you mange the bee population
you manage the P’s
“Several techniques are employed simultaneously to solve specific pest problems”
Alternative BMP’s Best Management Practices
names: Alternative Treatments (non-pesticide)

5. IPM Dewey M. Caron
IPM is a decision-making process for control of PESTS
PEST = pathogens, parasites, predators of honey bees, their colonies &/or products
Bee Mites have changed the face of beekeeping – no longer bee-havers
We are management specialists!

6. Four Fundamental Strategies for Pest Management Dewey M. Caron
Do nothing
Reduce numbers of pest
Reduce susceptibility of the host
Use combinations of the last two

7. IPM Essentials MONITORING We MUST -Understand bee/mite life cycle
- be able to ID mite & predict #
Mite levels fluctuate within & between: seasons,
bee yards and colonies. We must carefully test
and then use best estimates to determine risk level
IF RISK LEVEL WARRANTS – THEN TREAT

8. enters larval cell as it completes development. She hides on side wall
Adult female mite
enters larval cell as it
completes development.
She hides on side wall
as pre-pupa spins cocoon
Illustration series from Martin
IN: Mites of Honey Bees
Dadant & Sons, Inc 2001

9. In 60 hours she lays
1st egg (male).
After 24 hours she lays
female egg one every
24 hours

10. Her son (male)
develops feeding
on pupa & mates
w/ sister as she
matures

11. When adult bee
emerges 1.3 adult
female mites are
mature – if eggs
on drone 3X are mature

12. THINGS TO KNOW WE CAN ONLY ESTIMATE VARROA LEVELS
VARROA LEVELS VARY WITH
TIME OF YEAR
SIZE OF COLONY
AMOUNT OF BROOD
PREVIOUS VARROA TREATMENT
NO ONE TEST FOR VARROA WILL FIT ALL SITUATIONS
SOME TESTS ARE MORE ACCURATE

13. WHY TEST? OBVIOUS: NOT SO OBVIOUS: PREVENT COLONY LOSS MITE RESISTANCE
KNOW WHAT’S COMING UP
PREVENT OVERTREATMENT
SAVE MONEY

14. WHICH TEST TO USE? MITE DETECTION METHOD SUMMARY
METHOD COST TIME VISITS *SENSITIVITY ** RELIABILITY
Visual Inspection zero 2 min very low very low
Opening Drone Cells zero 5 min high low
Ether Roll low 5 min low medium
Washing low 5 min high high
Sugar Shake low 5 min high high
Tobacco Smoke moderate 30 min low low
Natural Drop moderate 24 hrs low high
Miticide high 24 hrs very high? very high?
*SENSITIVITY: ability to detect very small numbers of mites
**RELIABILITY: can depend on the test results
? Are the mites resistant to the miticide?

15. WHEN TO TEST? OBVIOUS ANSWER: In time to prevent colony loss
NOT SO OBVIOUS:
Brood = Mites and each area/climate varies
Mite levels: lower in spring to higher in fall
Test in time to allow treatment before honey flow
Remove honey asap and test.

16. HOW TO TEST
1. Natural Drop
2. Sugar Shake

17. HOW TO TEST
Alcohol Wash
Visual - Drone Brood

18. IPM THRESHOLD Monitoring can supply a number a “guesstimate” One or more numbers can be obtained use number(s) to evaluate mite population - one mite in sample = X mites in colony Determine an appropriate risk level - one mite vs 100 vs 1000? Assumption: mites in fall represents a minimally acceptable conservative risk??? Balance of costs vs benefits
Basics of the rational of IPM. It assumes a pest situation (host honey bee) can function with some base level of pests (mites) and still function normally. We determine a threshold, test the threshold and then can assign some level of risk to exceeding the threshold level of pests.

19. Threshold
An acceptable level of pests [mites] – determine necessity of further controls
A number to use to evaluate mite control efficacy efforts
Allows estimation of risk if no pesticide chemical is integrated into the control
The basis for IPM – a decision process utilizing modern pest control practices

20. MITE NUMBERS & TREATMENT
TIME OF YEAR
NATURAL DROP
ALCOHOL WASH
SUGAR SHAKE
VISUAL DRONE BROOD
SPRING
AHEAD OF HONEY FLOW
1-2 (8d)
1% of sampled bees
NA/
SUMMER /FALL
END OF HONEY FLOW
10 (30d)
5% of sampled bees
7% of sampled bees
1% of drones sampled (100)
WINTER
OCT-NOV
1-2
N/A
This numbers on this chart are the averages of my research.
They are likely on the conservative side.
** NUMBERS AND PERCENTS ARE GUIDELINES FOR TREATMENT
** BLACK NUMBERS ARE TREATMENT THRESHOLDS
** RED NUMBERS ARE DAMAGE THRESHOLDS

21. Threshold Spring/summer (April or May or Mid-June)
Sticky boards – over 5-10
Adult bees – over 3-4
Brood – over 5%
Exceeding threshold means additional control may be useful
Pre-fall (mid-August, Sept too late!)
Sticky boards – over means additional control
Adult bees – over 10-12
Brood – over 5-10%
Exceeding threshold means additional (chemical)
control needed
These threshold numbers seem high

22. Let’s Not Lose Control - Chapleau
THANK YOU - Lance