Frequently Asked Questions about Varroa Mite

What is a varroa mite?

The varroa mite is a tiny external parasite which attaches itself to the surfaces of honey bees and feeds on hemolymph (blood).  The adult female mite is about 1/16” wide, reddish brown and has a crab-like shape.  The scientific name is Varroa destructor Anderson and Trueman.  In Hawaii, its only known host is the common (“western” or “European”) honey bee.   Elsewhere in the world, it can utilize a different species called the “Asian” or “Oriental” honey bee.

Varroa Mite photo   

Why are varroa mites a problem?

Varroa mites are one of the most destructive pests of honey bees.  Adult female varroa mites lay their eggs in the brood cells of bee hives.  The mites feed on bee larvae and pupae, resulting in deformation of the wings and bodies of bees when they develop and emerge as adults.  They also feed on adult bees.  The feeding causes a decline in bee populations which ultimately reduces pollination necessary for the production of tropical fruits and vegetables.

Where are the mites found elsewhere in the world?

Varroa mites are widely dispersed throughout the world.  Hawaii was one of the few places that remained free of this mite until its detection on Oahu in April 2007.  HDOA’s varroa mite surveillance program detected varroa mites in a swarm trap near Hilo Bay on August 22, 2008.  A few varroa mites were also found in a feral beehive a day later.  HDOA staff is currently deploying additional swarm traps to determine the extent of this infestation in Hilo.  Bees are also being collected from managed beehives in the Hilo area.  Surveys conducted on Maui, Kauai amd Molokai have not detected the varroa mite.

How did the varroa mite get here?

This has not been determined, but it probably got here by hitchhiking on live bees that were transported or in shipments of beekeeping equipment that had been used recently.  According to HDOA Plant Quarantine regulations, it is illegal to import live bees or used beekeeping equipment that has not been certified by the HDOA for shipment into Hawaii.

How does the varroa mite spread?

The varroa mite can be spread to other areas in various ways:

  1. By hitchhiking on infested honey bees and contacting uninfested bees
  2. By honey bees from stronger uninfested hives “robbing” honey from weaker mite-infested hives
  3. By hitchhiking on other flower-visiting insects
  4. By the movement of infested managed hives or recently used beekeeping equipment to other areas

How can you get rid of varroa mites?

Currently, the only licensed pesticide in Hawaii for use on varroa mites is Apistan®.  On the mainland, varroa mites have developed a resistance to Apistan® so other chemicals have been developed.  HDOA is working on licensing other pesticides so they are available for beekeepers in Hawaii.

What is HDOA doing to prevent the spread of the mite to the neighboring islands?

HDOA has established an interisland quarantine which restricts the movement of bees or bee equipment off of Oahu.  HDOA is also establishing honey bee-free buffer zones around airports and harbors on Oahu and is continuing to conduct detection surveys for the varroa mite on the neighboring islands.

What can beekeepers do to determine if they have the varroa mite?

HDOA is continuing to monitor honey bee hives on all islands to detect the presence of varroa mites.  Beekeepers are urged to provide samples of at least 500 honey bee adults to the nearest HDOA office for testing.  Contact HDOA bee specialist, Dr. Mohsen Ramadan, at (808) 973-9530 for details on how to sample bees. 

As a beekeeper, will I be compensated if my hives are determined to be infested with the varroa mite and are destroyed?

HDOA is working with beekeepers to set up a process where they can be compensated for destroying their varroa mite-infested bee hives.

Why are a huge number of honey bees congregating on my property?

The huge number of adult honey bees gathering together is a swarm of bees which has divided off from a larger established colony.  If it is near a harbor or airport, please report it to the State’s toll-free Pest Hotline at 643-PEST (7378).  The HDOA is keeping a honey bee free zone around harbors and airports.  In addition, HDOA may want to obtain a sample to determine if it is infested with varroa mites.


For questions regarding the varroa mite or honey bees please call:

Oahu:                                     973-9530

Hawaii:                                   974-4140

Maui, Lanai, Molokai:      873-3555

Kauai:                                     274-3069