Midges are common in many parts of the world, as many who go walking in remote areas will know. The bite of the midge is not poisonous but is very irritating. It is the sheer volume of a swarm of these insects that is intimidating.
On one occasion on the Isle of Skye in North West Scotland (an area particularly prone to midges), I stepped on a tussock of grass and disturbed a swarm. Their number was so concentrated that a number entered my nose and mouth and met in the middle. The effect of being bitten by a swarm of midges is like being doused in a particularly virulent itching powder. Those of you who have experienced being bitten in this way will even now be scratching at just the thought of them!
The most ferocious midge is found in Scotland and is the Highland midge (culicoides impunctatus), which is found mostly in the north and west and thought to provide some 90% of midge bites. There are various other sub-species on most continents and tend to be between one and half and four millimetres in length. Midges are attracted by the carbon dioxide emitted by humans and animals and frequent damp areas where they lay their eggs. Boggy and woodland areas are favourite habitats and open hillsides avoided.
Interestingly midges are quite important to the environment. The larvae are detrivores, meaning they feed on dead plant and dying plant material in peat bogs and silt in ponds and lakes. This activity helps to break down the material. Also adult midges are an important food source for bats and birds.
They are most active at dawn and dusk, the cooler times of day, between June and August each year. They tend to disappear as soon as the first frosts occur. Of course the times can vary according to the temperatures of the particular year. Curiously the midge is quite particular about weather conditions and avoids direct sunlight as well as anything more than a very light breeze.
The quantity of midges can vary year on year depending on the severity of the preceding winter, the temperature and the rainfall.
It is the female midge that bites. They have two batches of eggs in a year but it is only the second batch (in late summer) that requires the female to find blood to ensure the survival of the young. When a midge bites it injects a small amount of saliva, which can cause an allergic reaction in some people. At the same time, the female also releases a pheromone to communicate to others that a blood supply has been found. So even if just one midge has bitten you, you are in trouble if you stay around!
Although midges cause no real harm to humans, their effect on animals can be a problem. They can carry the viral disease Bluetongue to ruminants such as cattle, deer and sheep and this is all too often fatal. They can also carry the devastating disease Myxomatosis to rabbits.
There has been much debate as to the methods to discourage midges. Various commercial solutions are available usually containing diethyl toluamide (DEET) and dimethyl phthalate (DMP) and have varying degrees of success. More natural deterrents suggested include citronella and eucalyptus. Walnut leaves wiped on the skin are said to deter the beasts but Bog Myrtle, Cotton Lavender (Santolina) or Artemisia 'Powis Castle' are also championed. Even using layers of sun tan cream so thick the midges cannot get through has been reported to have some success.
Perhaps the answer lies in making sweat taste nasty to midges. For this reason two dessertspoons of distilled vinegar a day are recommended or raw garlic or vitamin B supplements (for their vitamin B content, Marmite and Vegemite might do the trick).
A simpler solution is to wear a net veil over a wide brimmed hat to keep the midges at bay. The most curious solution is recommended in many parts of Scotland and that is Avon Cosmetics' Skin-So-Soft lotion!
It is noticeable that midges are attracted to dark clothing so wearing light coloured clothing would help discourage them.
Clearly the methods of discouraging midges need experimentation by the individual. Whatever the outcome and despite the nuisance caused it is obvious the midge is here to stay. It seems this tiny irritating bug has to be endured.