Friday, April 24, 2009

OBA Tech Team - Latest Research & Recommendations

OBA Tech Team Hive Management Recommendations

Allison Skinner from the Ontario Bee Association's Tech Team spoke at our local bee meeting on 23 April 2009.

My notes from the meeting are transcribed below. As always, bear in mind they may not be 100% accurate. Any errors or omissions are my fault and not the speaker's.

Allison worked in California again this winter with beekeepers working in the Almond industry.

She mentioned she met on queen breeder - a small queen breeder - who breeds only 11,000 queens a year.

There are different ways to make hive splits:

1. Walkaway Split - you walk away from a queenless hive and let the bees make their own queen.

2. Queen Cell - you purchase a queen cell and implant it into the hive to hatch out in a short period of time.

3. Mated Queen - You purchase a mated queen which you insert in a queen cage into the hive and wait for her to be released/accepted by the hive.

Positives & Negatives:

With option #1, the walkaway, it is free so there's no cost. On the downside, you have no idea of the queen's genetics (hygienic or not) nor the genetics of any drones she mates with.

With option #2, you don't have to spend too much money for the queen. On the upside, you will know the genetics of this queen but on the downside, you won't know the genetics of any males she mates with.

With option #3 a mated queen, on the upside, the genetics of the queen and drones is known.

The Tech Team did a study that focused on 10 colonies each. They focused on honey production, not pollen. They studied queen acceptance, supersedure, brood quality (I missed a couple points here).

In June, they divided up all the frames in the bee yard and monitored for Varroa Mites. They created sequential splits. They created the walkaway hive first, giving them an advantage of being first. Then 10 days later they added a queen cell to a hive and after that a mated queen.

They tagged all the queens and clipped their wings so they could track them.

They checked the hives in July:

Option #1 - In the walkaway split, the queens were accepted in 9 out of 10 hives

Option #2 - With the inserted queen cells, 6 of 10 hives had queens

Option #3 - Mated queens were laying eggs in all 10 hives

They checked again in August:

1 colony was queenless from the walkway split (option #1)

1 hive from the queen cell hives (option #2) had a drone layer

10 of the 10 mated queens were present and laying eggs

If you are planning on inserting a mated Russian queen into a hive, with non-Russian bee stocks there can be acceptance problems. It is recommended that you wait 5 to 7 days before introducing a Russian queen.

They studied colony strength:

The lowest strength hive was the queen cell group (option #2). It was a poor honey year for all the groups. They looked at the number of empty brood cells in a 23m2 space. They used a square cut-out as a template, laying it over the comb and counting the number of cells with brood inside the template.

They found that Varroa Mites were less with the mated queen; however, Varroa Mites as a whole were low.

They noted all stings - the only bee stings received were from the walkaway hive with the queen that the bees made themselves.

There was a study done by Manitoba on queen comparisons, considering variables. The results of the study will be published later this year. Two components reported on were the length of the queen's abdomen and sperm counts.

They looked at queens raised at different times of the year and they found there was a positive correlation with the larger abdomen. They found abdomens from 10 milliliters to 10.7 milliliters.

Sperm counts were positively correlated by the sample dates of when the queens were raised. Queens raised later in the year (June) had the higher sperm, counts. Therefore it was concluded that it is better to get a queen in June even though it's preferred to have queens in April or May.

Update on Nosema:

Nosema apis often has dysentery marks showing on the outside of the hive. Often the spores are on the top bars of the hive.

If submitted bees for sampling of Nosema apis or Nosema ceranae, be sure to collect older bees who are returning to the hive and not the young bees inside.

To see the spores they crush a bee's abdomen in 1 ml of water and then view under a microscope. They can't tell the types of Nosema apart under a microscope and must still do DNA testing to be able to tell the difference between the two.

Nosema ceranae was first noticed the fall of 2006 and spring of 2007. 24 of 25 hives tested were found to have Nosema ceranae so it is presumed to be fairly widespread.

It is recommended to treat hives with Fumigilin B and to reduce the stress on bees by controlling Varroa Mites and ensuring the bees receive proper nutrition.

In the spring of 2008 the Tech Team focused on Nosema. They looked at 67 bee operations in Ontario, most from the Niagara area. In 2008, Ontario reported bee colony losses of 33%. The average spore count per bee in 2007 was 5,571806 and in 2008 4,748440. The tolerance threshold of spores per bee is 1 million spores.

They had many enquiries about what to do with weak colonies in the spring. They looked into this by doing a study of the health of queens in weak colonies. They tested the health of 16 queens from weak hives. Of the 16, only 5 queens did not have Nosema. 1 had over 2 million spores. Nosema does lead to queen infertility. It is better to requeen. The queen usually catches Nosema from the workers.

2009 recommendations are that a spring inspection be conducted and the hives be monitored to see if treatment is required.

It is recommended that frames in hives not be continually rotated. Instead, rotate out of the hive and replace with fresh frames and foundation 3 frames per year per colony.

A question was raised regarding replacing the hive body, however there is no research at this time to suggest that is necessary.

Treat the hive with Fumigilin B mixed up in sugar water and put in a plastic baggie. The baggie is given two 5" slits and then placed directly on top of the hive bars. A spacer sites on top of the hive and then the inner cover, and outer cover on top. The bees will eat the syrup in about 2 or 3 days.

In Sept/Oct when treating with Fumigilin B be sure the bees take all the feed before the cold weather sets in.

Spring feeding with Fumigilin B could be important because there tends to be a build-up of Nosema in the spring.

Fumigilin B stays active for a while but it breaks down in light and should be stored in a dark container. There has been some questions raised about Fumigilin B - does it settle at the bottom after being mixed in sugar water as in barrel feeding? They are starting to look at spring feeding instead.

Breeding for Tolerance:

Blanket treatments and over treating without sampling makes it worse. Bees should be bred from colonies with low Nosema spore counts.

They no longer think that IAPV (Israeli Acute Paralysis Virus) is a direct cause of CCD. It was noted that IAPV was always found along with the Kasmir Bee Virus, but never on its own. Some sampled hives did have just Kasmir Bee Virus alone.

Hygienic bees remove brood from cells that are infected with Nosema.

The Tech Team has worked with Bill Ferguson from Ferguson Apiaries on stock selection and a hygienic breeding program.

Marla Spivak's thesis student from the University of Minnesota did experiments where she isolated chalkbrood in paraffin wax and then impregnated frames of comb with this brood. They also used a chalkbrood violate pheromone.

They also inserted a brood pheromone in the same frames and recorded where each were put. They observed whether nurse bees removed the paraffin chalkbrood to cleanse or whether they capped the cells.

A project that the Tech Team would like to do if there were enough funds would be to study Residues in Wax or Honey.

The Tech Team will be completing the provincial study this year. Beekeepers at the meeting were requested to complete a survey for the Tech Team.

Also, at the cost of $150 they could have their wax tested.

Allison is married now and has a new last name... but I wasn't fast enough to catch it!
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