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|Species:||often mislabeled as V. jacobsoni
Varroa destructor is an external parasitic mite that attacks honey bees Apis cerana, Apis mellifera, Bombus pennsylvanicus, Palpada vinetorum and Phanaeus vindex. It can only replicate in a honeybee hive. It attaches at the body of the bee and weakens the bee by sucking haemolymph. In this process the mite may also spread RNA viral agents and bacteria to the bee. A significant mite investation will lead to the death of a honeybee colony, usually in the winter. The varroa mite has been the parasite with the most pronounced economic impact on the beekeeping industry.
Origin
Varroa destructor was until recently thought to be a closely
related mite species called Varroa jacobsoni. Both species
parasitize the Asian honey bee, Apis cerana. The mite species
originally described as V. jacobsoni by Oudemans in 1904 is
part of the same species complex, but not the same species that
made the jump to Apis mellifera. That jump probably first took
place in the Philippines in the early 1960’s. Only after A.
mellifera were imported to the Philippines, thereby coming into
close contact with Apis cerana and their accompanying parasites,
was varroa known to be a parasite of A. mellifera. Up until 2000, scientists did not positively identify Varroa destructor as a
separate species. In 2005, we know that the only varroa mites that can reproduce in colonies of Apis mellifera (Western honeybee) are the Korea and Japan/Thailand genotypes of Varroa
destructor. Varroa jacobsoni is a fairly benign parasite of Apis cerana. This late identification led to some confusion and mislabeling in the scientific literature.
Varroa destructor on bee larva
Anatomy
reddish-brown in color
1.00-1.77 mm long and 1.50-1.99 mm wide flat button shape
eight legs
Life Cycle
The female mite enters a honeybee brood cell. As soon as the cell is capped, the mite lays eggs. The young mites hatch in about the same time as the young bee develops and leave the cell with the host.
The model for the population dynamics is that there is exponential growth when bee brood is available and exponential decline when no brood is available.
Reproduction
Mites reproduce on a 10-day cycle. In 12 weeks the number of mites in a Western honeybee hive can roughly multiply by 12. Russian honey bees are one third to one half less susceptible to mite reproduction.
Source: Russian Queens Bee-little Mites' Impact by J. Raloff, Science News, Aug. 8, 1998
Worldwide Range Expansion
1984 Switzerland
1987 USA
1989 Canada
1992 England
2000 New Zealand
Control methods in beehive
- pyrethroid insecticide (Apistan)
- organophosphate insecticide (Coumaphos(Check-mite))
- oxalic acid
- formic acid
- Screened bottom board with sticky board
- Foodgrade mineral oil as vapor and in direct application on paper or cords
- Essential oil especially thyme oil
- freezing or heating drone brood method
- swarming or queen arrest method
See also
