Bee Enemies

 
Please click on the picture to view larger USDA-ARS images.


  Varroa Jacobsoni Mites:
More Varroa Mites:
Varroa Mites Inside Brood Sell:
  Varroa Mite on a Developing Bee:



"USDA ARS scientists Dr. John Harbo and Dr. Jeffrey Harris at the Honey Bee Breeding Laboratory in Baton Rouge, Louisiana, have defined and tested a trait of the honeybee which appeared to suppress mite reproduction (SMR). Recently it has been better defined as "varroa sensitive hygiene (VSH)." This is a form of behavior where adult bees remove pupae that have reproductive mites but do not disturb pupae that have mites that produce no progeny. Dr. Harbo and Dr. Harris proved the effectiveness of the SMR/VSH trait by exchanging queens between resistant and susceptible colonies. Each time a resistant queen was put into a susceptible colony, the mite population went down. On the other hand, every time a susceptible queen was placed in the resistant colonies, the mite population increased.
Recent studies by Dr. Spivak and Dr. Harbo have shown that the SMR trait might be best described as a "varroa-sensitive hygienic behavior". SMR/VSH bees remove mites that have started to reproduce. The reproduction of mites triggers their removal by the bees. The only mites left in the cells are nonreproductive or sterile. So there is evidence for selective removal of reproductive mites from brood cells. A goal of the USDA SMR Project is to distribute the SMR/VSH trait for resistance to Varroa mites to queen breeders around the country. The object is to cross these bees with beekeeper's own well adapted stock. This will maintain the genetic diversity of American bees while enhancing this important trait. Once in the hives of beekeepers, further selection and improvement can be made for honey production, other disease resistance mechanisms, and other beneficial traits. Recent tests have shown that SMR/VSH queens retain an acceptable level of mite resistance when they are free mated to unselected drones. The best way to get the maximum amount of the trait into a line of bees is to begin with a pure SMR/VSH breeder queen so her daughters mate with your local drones. Workers from pure SMR/VSH queens have a hyper-hygienic behavior where their workers remove more brood than is necessary or desirable. This will show up as a deterioration of the breeder's brood pattern after about six weeks. The regular addition of frames of sealed brood from other colonies will keep the colony strong. Daughters queens of pure SMR/VSH breeders who are out crossed by natural mating have good brood production and an acceptable level of mite resistance. The SMR/VSH trait has proven to be extremely effective at controlling Varroa. It holds great promise as a permanent solution, but the work is not yet finished. There is still considerable variation in crosses with different lines of bees, and so should still be thought of as as a work in progress." USDA

"To demonstrate Varroa-sensitive hygiene by SMR bees, a highly infested brood comb was cut into halves, and each half was placed in a cage with 2,000 test bees for 24 hours. Shown here is the brood comb of the control bees, which removed only 12 pupae and uncapped only another 19 pupae (33 percent of uncapped cells were infested with Varroa mites)." USDA

"To demonstrate Varroa-sensitive hygiene by SMR bees, a highly infested brood comb was cut into halves, and each half was placed in a cage with 2,000 test bees for 24 hours. Shown here is the brood comb of the SMR bees, which removed 215 pupae and uncapped another 178 pupae (90 percent of uncapped cells were infested with Varroa mites). USDA

Hygienic Behavior (Video Clip)



How to fight against Varroa Mites without chemicals



1. The USDA helped Pierco out with the mold for this new hard plastic, beeswax coated frame for use as an Integrated Pest Management technique for combating the Varroa Mites. The frame is colored so you will be able to see which frame it is in the hive. You should have two for each hive so you can rotate. Bees draw beautiful drone cell foundation with it. It is so much easier to use than the straight unwired drone foundation.

81/2 x 161/2 Medium Brood Drone Comb Foundation 10 Sheets Per Package Ship Wt. 2 lbs. Per Package. Did you know Varroa mites are attracted to developing drone brood much more than they are attracted to worker brood? By using a few frames of drone comb you can lure Varroa mites to the developing drone brood, and the mites become trapped within the drone cell when the bees cap the cells. Remove the frame of capped drone cells. Put it in a plastic bag in your freezer overnight to kill the mites. Remove from the freezer and let warm. With the cappings scratcher on page 45 break open the drone cells. Then, put the frame back into the colony and allow the worker bees to clean out the cells, getting rid of the dead varroa mites and drones. After the queen lays drone eggs in these cells again, this Varroa trapping cycle is repeated. Therefore the above cycle may be repeated to capture and kill more mites. By utilizing this process a large percentage of Varroa mites are naturally eliminated without chemicals.
This product was added to Dadant catalog on Monday 20 May, 2002.


2. Varroa Screened Bottom Board


3. Raise Your Own SMR/VSH Bees

According to Betterbee, "For those interested in raising their own queens that manifest hygienic behavior, the drone comb can be used to check for such behavior. Cut a patch of brood about 3" x 3" in a rhombus shape out of the frame of capped drone brood. Place the piece of comb in the freezer for 24 hours - then replace the comb. By comparing how quickly and thoroughly each colony removes the dead bees and cleans up the comb, you can select the queen from which to breed. Hopefully, this hygienic behavior will translate into more mite and disease resistance in your bees."

4. Buy ARS Russian or SMR/VSH Bees.

5. A modified two queen system

The weak condition of bee colonies in North America

Using Beetle Biology To Protect Beehives



 

Back to main page