NOSEMA & MITES SURVEY

 

 

IPM Strategy

Integrated Pest Management (IPM) suggests that the beekeeper makes a decision for treatment based on level of pests in the colonies.  It is no longer advisable to make use of pesticides year after year, because this leads to resistance of the mites to the active ingredient.  Instead, it is now recommended to monitor the pests or diseases, to know the level of infestation.  If the level of infestation observed exceeds a pre-determined value (called Economic Threshold Level-ETL), then it is recommended to take action, i.e. treat with a soft chemical like formic acid or oxalic acid.  Organic acids are found in nature at lower levels, and are not such a big problem for residues.   Moreover, honeybees are not known to become resistant to such products.

 

In our breeding program, we have followed this method to allow the Russian stock to defend itself against mites on its own merit.  What we found is the level of mites reaches dangerous levels after 3 years without treatment.  Therefore, we concluded that a treatment should be applied once a year or every 2 years at thee most.  This is an improvement because we use to treat twice a year before.

 

The key is monitoring the pests regularly, not to get caught behind, where it becomes too late.  We make extensive use of sticky boards inserted on the floorboards of the colonies to trap dead mites falling off the cluster.   We survey a minimum of 25% of all colonies.  This gives us a good idea of the mite situation.  We leave the sticky board in for a period of 24 to 48 hours.  We then calculate the 24-Hour mite count for each colony surveyed.  This gives us a standardized 24-hour apiary average for each apiary.  We use this value to decide if we are going to treat this apiary or not.  We do this survey in early spring and late summer.

 

Using these results, we have established the following guidelines as of fall 2009:

 

In the spring, late April:

If level are > 5, treat with Mite Away II in May when daytime temperature reaches 10° C.

 

In early September:

If levels are < 20, treat with Oxalic acid in November.

If levels are > 20, treat with Formic Acid in September and treat with Oxalic Acid in November.

 

2002

This is the year where we requeened most of our colonies with Russian stock.  We therefore treated all colonies, in all apiaries with Check-Mite to start afresh with very low mite counts.

 

2003

We conducted the survey in September and found very low level of mites (between 0 and 3).  We treated one apiary with Mite-Away II, and 2 apiaries with Check-Mite in late fall (partial treatment).

 

2004

In September 2004, we conducted an extensive Varroa mites survey, using sticky boards in all our apiaries, to determine the average level of mites infestation in each particular apiary.  Our survey indicated that only 2 apiaries needed treatments out of 10.

 

2005

We conducted the survey in the spring and fall.  In the spring many apiaries showed level of infestation >10, so we treated with Mite-Away II or home-made formic acid pads using veggie bags.  All apiaries showed high levels of mites in the fall as well, therefore we treated all apiaries with formic acid or Check-Mite.  All nucs were treated with oxalic acid.

 

2006

We conducted the survey in the spring and fall.  In the spring levels were below 5 for the most part, with an average of 2.1, so we did not apply any treatment.  In the fall, levels were much higher with an average of 24, so we treated all apiaries with formic and oxalic acid.

 

2007

No survey in the spring.  In September, composite bee samples (10 colonies per sample of 150 bees each) from all colonies were sent to the Bee Lab in Eganville (Tanglewood Honey-Jim Anderson) to check for nosema spores.  Also in September, sticky boards were used to evaluate varroa mites population in every apiaries.  The results are shown below in table 1.  We treated 3 apiaries with Fumagillin, and 5 apiaries with formic acid (Mite-Away II).  All colonies were treated with oxalic acid later in November. Nosema are shown as million spores per bee and varroa is shown as # mites in 24 hour natural mortality.

 

Table 1 – Survey Results for Varroa and Nosema -  Apiaries’ Averages and Treatments – 2003 to 2007

 

APIARY

ID

2003

2004

2005

2006

2007

 

SPRING

VARROA

FALL

VARROA

SPRING

VARROA

FALL

VARROA

SPRING

VARROA

FALL

VARROA

SPRING

VARROA

FALL

VARROA

FALL

VARROA

FALL

NOSEMA

 

02

N/A

N/A

N/A

N/A

N/A

N/A

N/A

15

Mite-AwayII

Oxalic Acid

7.8

Oxalic Acid

0

 

03

0

3.4

Check-Mite

0.3

1.2

3.6

67.0

Mite-Away II

6.7

no treatment

28

Mite-AwayII

Oxalic Acid

18.6

Mite-AwayII

Oxalic Acid

2.0

Fumagilin

 

04

N/A

N/A

N/A

N/A

N/A

N/A

N/A

10.3

Mite-AwayII

Oxalic Acid

6.4

Oxalic Acid

0.2

 

08

0

0.1

0.3

4.8

6.2

Formic Acid

87.2

Check-Mite

0.8

no treatment

9.8

Mite-AwayII

Oxalic Acid

5.0

OxalicAcid

0.07

 

12

0

0.4

1.2

7.7

8.9

Formic Acid

65.9

Check-MIte

0.6

no treatment

17.5

Mite-AwayII

Oxalic Acid

5.1

Oxalic Acid

0.08

 

14

0

3.1

3.1

10.4

Mite-Away II

0.8

55.6

Check-Mite

2.4

no treatment

61

Mite-AwayII

Oxalic Acid

8.7

Oxalic Acid

0.08

 

15

0

0.3

0.9

3.7

13.9

Formic Acid

55.4

Mite-Away II

4.8

no treatment

33.2

Mite-AwayII

Oxalic Acid

6.5

Oxalic Acid

0.33

 

 

17

0

3.1

Check-Mite

1.0

1.8

7.6

62.8

Mite-Away II

1.0

no treatment

19.3

Mite-AwayII

Oxalic Acid

36.8

Mite-AwayII

Oxalic Acid

0.48

Fumagilin

 

19

0

0.4

N/A

1.1

20.0

Formic Acid

92.1

Mite-Away II

1.3

no treatment

36.25

Mite-AwayII

Oxalic Acid

14.4

Mite-AwayII

Oxalic Acid

0.02

 

21

0

0.3

N/A

5.6

9.9

Formic Acid

114.9

Check-Mite

0.4

no treatment

3.6

Oxalic acid

21.3

Mite-AwayII

Oxalic Acid

1.28

Fumagilin

 

22

0

0.3

0.6

2.9

11.3

Mite-Away II

34.0

Mite-Away II

2.0

no treatment

31.0

Mite-AwayII

Oxalic Acid

N/A

N/A

 

23

0

8.8

Mite-Away II

N/A

N/A

N/A

N/A

Check-Mite

N/A

N/A

N/A

N/A

 

24

0

0.1

0.5

10.4

Mite-Away II

0.6

78.4

Check-Mite

0.8

no treatment

26.4

Mite-AwayII

Oxalic Acid

41.5

Mite-AwayII

Oxalic Acid

0.05

 

AVG

0

2

1

5

8

71

2

24

15.6

0.38

 

 

2008

This is the year we realized Nosema apis & Nosema ceranae has appeared in force to devastate many colonies around the world.  We found it in our own bees with alarming level.  We decided not to treat in the fall but to sample bees at the entrance door in September, in order to find breeder colonies with lower levels in comparaison to the apiary average.  We treated with Formic Acid and Oxalic acid as usual. Table 2 shows results.  Nosema are shown as million spores per bee and varroa is shown as # mites in 24 hour natural mortality.

 

Table 2 - Survey Results Varroa and Nosema

Apiaries’ Average and Treatments - 2008

 

APIARY ID

FALL

 

VARROA

NOSEMA

TREATMENT

02

8

N/A

Oxalic acid

03

13

2.97

formic acid pads Mite-Away II

Oxalic acid

04

11

N/A

Oxalic acid

08

39

6.15

formic acid pads Mite-Away II

Oxalic acid

12

35

2.38

formic acid pads Mite-Away II

Oxalic acid

14

11

3.14

formic acid pads Mite-Away II

Oxalic acid

15

74

5.15

formic acid pads Mite-Away II

Oxalic acid

17

12

5.62

formic acid pads Mite-Away II

Oxalic acid

19

34

5.04

formic acid pads Mite-Away II

Oxalic acid

21

14

3.74

formic acid pads Mite-Away II

Oxalic acid

24

45

N/A

formic acid pads Mite-Away II

Oxalic acid

AVG

27

4.27

 

 

 

2009

We sampled again for nosema levels in early spring and found that most levels had increased since fall 2008.  We decided to treat with Fumagillin, using the baggie method, at the recommended dosage for Nosema ceranae, 4 applications at 1 week interval. No other treatment in the spring.  In September, we treated again with Fumagillin, one application with baggie method, dosage for Nosema apis. We could not treat all colonies because in some apiaries we first fed heavily, consequently the bees would not take the baggie afterwards. We plan to treat these apiaries early next spring. No formic acid, only oxalic acid applied to all colonies.  Results are shown in table 3. Results for nosema levels in fall will be available later this winter. We will post the results when we receive them from the Tech-Transfer Team.  Nosema are shown as million spores per bee and varroa is shown as # mites in 24 hour natural mortality.

 

Table 3 - Survey Results and Treatment for 2009

APIARY ID

SPRING

FALL

VARROA

NOSEMA

TREATMENT

VARROA

TREATMENT

02

0.5

N/A

Fumagilin-B

5

Fumagilin-B

Oxalic acid

03

1.5

6.5

Fumagilin-B

7

Oxalic acid

04

3.9

N/A

Fumagilin-B

10

Oxalic acid

08

0.5

10.1

Fumagilin-B

3

Fumagilin-B

Oxalic acid

12

0.8

13.0

Fumagilin-B

6

Oxalic acid

14

0.0

16.7

Fumagilin-B

2

Fumagilin-B

Oxalic acid

15

1.0

11.1

Fumagilin-B

17

Oxalic acid

17

0.7

5.4

Fumagilin-B

4

Fumagilin-B

Oxalic acid

19

0.3

13.3

Fumagilin-B

8

Oxalic acid

21

0.4

6.73

Fumagilin-B

3

Oxalic acid

22

N/A

N/A

Fumagilin-B

16

Fumagilin-B

Oxalic acid

24

0.0

N/A

Fumagilin-B

4

Fumagilin-B

Oxalic acid

AVG

0.9

9.8

 

7

 

 

 

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Page updated on January 2, 2010