The Varroa Mite
Varroa destructor, the Varroa Mite, originally emanating from Asia is an external parasitic mite that feeds by biting through the external skeloton of the adult and soft skin of the larvae bee, and through sucking, feeds on the Bees haemolymph / blood system.
Introduced to Ireland, and first detected in Co Sligo in 1997, hitchhiking on the backs of honey bees brought into Ireland. At that time the varroa mite had been in Europe since 1962 and had spread to the west coast of Britain before it was discovered that it had even entered the country.
It is ever present in the Hive and if left unchecked, will ultimately lead to the collapse and death of the colony. Through it's method of feeding it is an efficient vector of diseases, diseases that were mostly always present predating the mites arrival, but because of the mites method of feeding now makes the Honeybee more susceptible to infection.
The Asian Honeybee had through evolution, learned to co exist with this parasite much as many other animals do with their particiular parasites. In time the European honeybee will probably do also. Though since it has been introduced into europe, and ultimately here, it has devastated Honeybee colonies. If left unchecked in a hive it will lead over a season to the death of the colony.
The mite lives both on the adult bee, and on the larvae and pupating bee in the sealed wax comb brood cell. Therefore it takes a concerted effort and planned treatment schedule during late summer and mid winter, to keep the parasites numbers at a level that the bees can coexist with.
There are various forms of treatment that take the form of chemicals and organic acids.
Being a strong advocate of organic principles, as I intend to manage my new 17.5 acre Leinster Honey Farm. I use the two Organic acid options available to treat for this Mite. Both Formic and Oxalic acid, two acids found in the natural enviroment.
Formic acid is used by ants in their sting and Oxalic acid is found in different concentrations in certain vegetables. Both natural acids are applied after the honey crop has been removed and do not harm the bees, but do the varroa mite. Top right is a drop of mites after application of the oxallic acid. It is a sad fact that on introduction of this mite, within a few seasons all the wild Honeybee colonies were effectively wiped out here in Ireland. So as now the Honeybees we see on a warm summers day working tirelessly are from managed hives, or the odd short lived feral colony that has swarmed from a managed hive.
There are efforts afoot to breed Honeybees that are resistant to this mite. honeybees that exhibit enhanced hygienic traits such as mutual grooming of mites off each other and sensing and removing parasitized capped larvae.
In the meantime though, we must learn to live with this particular parasite and to limit its numbers in the hive through treatment.
I am happy to say with proper management and good Apiary hygiene, it can be controlled and healthy and prosperous colonies of honeybees can be maintained for the purpose of production of Premium Local Raw Irish Honey. Also just as importantly, or more so, for the good of the environment and pollination of all the essential wild Irish native plants.