Common pest profiles, preventive measures and controls


Depending on the species, thousands of ants can live with one or several queens in colonies. More than 6000 ant species are known. From a human viewpoint the queen is no more than a machine for laying eggs. She has an entourage of special workers and soldiers, who look after the larvae and protect the colony.

Ants generally feed on protein-rich and sugar-containing substances.

While the meadow ant workers can grow to 2 to 3.5 mm in length, the black garden ant workers are slightly bigger at 4 mm.

The meadow and black garden ants cause damage to patios or terraces and in the garden (for instance by undermining paving and damaging plants).

The pharaoh ant (Monomorium pharaonis) is found very often in tropical countries – and in Europe too. They live in the walls of houses and find their way into the house through small cracks and joints. Since they like warmth, colonies only occur in warm places .The pharaoh ant workers grow up to 2 to 2.5 mm in length. They eat both sweet and protein-rich foods and organic waste as well. In hospitals particularly there is the danger of the pharaoh ants spreading germs of all kinds, since they also have an appetite for used bandages. They are also a hazard in commercial kitchens, bakeries, etc.

Preventive measures and controls

  • Seal up all cracks and holes in walls
  • Get rid of the targets of the ant routes (for example food and waste)
  • Pour boiling water over the nests
  • Use insecticides (Ant Bait Station, Ant Powder, Crawling Insect Spray)

Lepinotus sp. is only 1 to 2 mm long and has nothing to do with the blood-sucking head louse. The pale-coloured book louse is a soft-bodied insect with scale-like wing pads and can only survive in rooms with a high humidity. The lice dehydrate if the humidity is lower than 60 %. The gland fluid in their mouth helps them to absorb moisture from the air.

In rooms that are too humid, book lice feed on paper goods such as books, files and wallpaper. Mass proliferation of Lepinotus frequently occurs in freshly wallpapered new buildings where a barely visible covering of mould develops and provides food for these pests. They also breed in food that is stored in excessively damp conditions, and as a result the food goes bad more quickly. Book lice can also infest drugs, textiles or mattress fillings.

Preventive measures and controls

  • Dry them out/kill them with a hairdryer or fan heater
  • Clean cupboards and let them dry completely; subsequently air them on a regular basis
  • Do not store books in damp cellars.

The basis rule is:
Keep homes dry and airing them correctly

Carpet BeetleAnthrenus scrophulariae is often mistaken for a ladybird when it feasts on pollen and nectar in the summer. The common carpet beetle is reddish brown with black and white spots and is only 4 mm long. The females fly into people’s homes or into storerooms, where they lay around 20 eggs on various materials. The larvae hatch after only a few days. They have hair bristles on their bodies that contain poison. Since they are not fond of the light, they often settle away from their feeding sites in cracks and crevices. It takes just under a year for the larvae to develop into beetles.

The larvae of the carpet beetle like to feed on dry animal products such as woollen textiles and furs. They also eat away at insect collections and stuffed animals, and can cause major damage to valuable collections.

Preventive measures and controls

  • Larvae on the wall should be wiped off with a cloth or removed using a vacuum cleaner
  • Infested textiles should be brushed out, beaten, washed, cleaned or ironed
  • These pests can be destroyed by very hot or cold temperatures
  • Beetles on windows indoors should simply be moved outdoors
  • Insecticides to be sprayed.

The basis rule is:
Regularly air and thoroughly vacuum carpets, taking care not to forget poorly accessible places

CockroachCockroaches, which hide in small cracks or crevices during the daytime, can reach lengths of 18 to 60 mm depending on species. They feed omnivorously on various organic substances, including tissue, leather and paper.

The German cockroach (Blatella germanica) is very common, and usually encountered in houses. It is relatively small and has a short life cycle of 3 to 8 months, depending on temperature. The German cockroach females carry their packages of 20 to 40 eggs with them for about 4 to 5 weeks, and then lay the eggs randomly shortly before hatching. The larvae shed their skins several times, and gradually resemble adult cockroaches more and more closely, only they are smaller and have no wings.

Cockroaches can be carriers of a high number of bacterial and viral diseases such as diarrhoea, leprosy, catarrhal colitis, infectious hepatitis, anthrax, salmonellosis, tuberculosis and fungus diseases (aspergillus flarus).

The cockroach’s excrement, skin and vomit are responsible for allergies. House dust mites and cockroaches are the commonest cause of insect allergies. In the USA 10 % to 12% of the population reacts allergically to cockroaches.

Cockroaches like e.g. the Oriental Cockroach (Blatta orientalis) and American Cockroach (Periplaneta americana) occur throughout the world, especially in tropical regions where the environment is humid and warm.

Preventive measures and control

  • Avoid accumulating rubbish and rotting substances
  • Do not leave food or meals uncovered
  • Keep kitchens and cooking untensils clean
  • Use insecticides

Drugstore BeetleThe drugstore beetle (Stegobium paniceum) is the most omnivorous of the storage pests. It is rust-brown in colour and grows to a length of 3 mm. The females lay about a hundred eggs, from which the adult insects develop in two to three months. The white maggots or larvae pupate in an oval cocoon spun from particles of food. The fully grown beetles live for one to two months.

The drugstore beetle is considered as omnivorous because it infests a broad range of vegetable and animal products. As well as bakery products it will eat soup cubes, chocolate, animal food and dried fish. Now and again it will eat savoury biscuits, and even develop a taste for chilli powder. Their presence can be detected from pinhead holes in the infested items. Packaging materials such as paper and cardboard are also attacked. Since the drugstore beetle can fly well, the source of infestation is often hard to find.

Because it is 12 to 18 mm long the yellow mealworm (Tenebrio molitor) is hard to overlook when it is crawling around in snow-white flour. The freshly hatched beetle is brown at first, and then turns black with light stripes on its wing cases. The females lay 150 to 200 sticky eggs in the food. The hatched larvae are the familiar mealworms, with a length of up to 28 mm. It may take a year and a half before the mealworms turn into beetles. Massive infestation is therefore fortunately rare. The adult beetles live for about 4 to 6 weeks.

Drugstore beetles and mealworms not only eat any pastry and bakery products, they also soil them as well. The flour turns lumpy and smells mouldy. They prefer leftover wheat and flour waste. Mealworms can also eat holes in planks and beams. In addition they can cause parasite infections – mealworms transmit parasite worms among other things.

Preventive measures and control

  • Keep food cool and dry
  • Immediately remove and destroy infested foods, and if it looks alright keep it in a deep freezer for three days
  • Vacuum-clean storage cupboards thoroughly (the cracks and crevices especially)
  • Keep new stores in sealed containers (jars, boxes)

The basis rule is:
Do not use insecticides in storage cupboards especially if food items are still in.

FleaThe human flea (Pulex irritans), cat flea (Ctenocephalides felis) and dog flea (Ctenocephalides canis) all cause fundamentally the same harm. One flea prefers humans, and the two others mainly infest cats and dogs.

Fleas grow to a maximum of 4 mm, are coloured either dark- or red-brown and have strong jumping legs. They lay up to 400 eggs in the environment of their hosts. The breeding places are mainly dust and dirt accumulated in crevices, joints and corners.

The thread-like legless larvae are about 5 mm long. They feed on organic materials and the blood-containing excrement of grown fleas. The larvae are found in floor areas, for instance on carpets, under skirting boards and in cracks. They take about 7 to 18 days to develop. A generation of fleas lives for about four to six weeks.

Fleas cause painful bites on human, cats and dogs, and they suck their blood. The cat flea is most widespread, and it can temporarily transfer to humans. Fleas often bite several times in direct succession, until their appetite is satisfied. The itching often lasts for days and sometimes weals form. Fleas can also transmit tapeworms and cause allergies.

Preventive measures and control

  • Pets, that is mainly cats and dogs, should be regularly de-infested
  • Flea hiding places should be vacuum-cleaned and suitably treated
  • Frequent vacuum cleaning and beating helps to stop flea larvae in carpets
  • Use insecticides (Crawling Insect Spray)

flyFlies feed on various organic substances including excrement, and sweet and other foods.

They can reach a length of 7 to 14 mm, and reproduce in dry areas, with breeding promoted by warm temperatures.

Flies lay up to 2,000 eggs, mostly in manure, faeces, compost heaps and rubbish tips (the Musca domestica species), but also on protein-rich substances such as meat (the Calliphora vicina species). The eggs develop into white maggots, which can grow up to 12 mm long.

Their movement between bad meat, excrement and foods is not only unappetising, it also makes flies the transmitters of germs and a source of food contamination.

As a result they can transfer pathogens for infectious diseases such as cholera, dysentery, typhoid fever, salmonellosis, hepatitis and poliomyelitis.

Flies which do not bite are:

  • the common housefly (Musca domestica)
  • the meat fly (Calliphora vicina)
  • the fruit fly (Drosophila melanogaster)

Flies which bite are:

  • the tsetse fly, the carrier of sleeping sickness (Trypanosomiasis)
  • the stable fly (Stomoxys calcitrans)
  • the horsefly (Tabanidae)

Preventive measures and control

  • Avoid accumulating rubbish and rotting substances
  • Do not leave food or meals uncovered
  • Keep kitchens and cooking untensils clean
  • Use insecticides (Fly Trap, Insect Strip, Flying Insect Spray)
  • Insect repellents provide sensible protection against biting flies (e. g. horseflies)

flour miteThe flour mite (Acarus siro) is a small sack-like mite. It only grows to 0.1 to 0.6 mm in length, is white and has red legs. Mites are generally very troublesome storage pests, because they are so small and hard to see. Their lethargy does not stop them reproducing rapidly (with up to 500 eggs per female), and the larvae develop in only about 17 days. During development into the adult mite they often pass through inactive stages, so that the larvae can survive long dry periods without food. Because flour mites belong to the family of mould mites, they thrive in warm and humid climates.

The flour mites usually infest flour, muesli and other dry vegetable foods. The affected products seem to be covered by a coat of light dust, crumble, smell sweet and taste bitter. For instance if a cake doesn’t rise, the cause can be mites in the flour used. Eating infested foodstuffs can also seriously harm your health. Allergies can occur that lead to high temperatures and headaches. Blisters and pustules may form on the skin, and serious stomach and intestinal reactions, even asthma attacks can result from eating food infested with mites.

Preventive measures and control

  • Destroy infested foods, put food that looks alright in a deep freezer for three days
  • Keep new stores in closed containers (jars or boxes)

The basic rule is:
Do not apply insecticides in storage cupboards which have any food items in them.

House Dust Mites

These minute insects have eight legs when adult, and so are classed as arachnids. The house mite (Glycyphagus domesticus) grows to a length of about 0.5 mm. It only reproduces in large quantities in warm rooms with high humidity, in which mould fungi are also present.

The house dust mite (mainly Dermatophagoides pteronyssinus) is quite common in house dust. It is only 0.3 mm long and whitish in colour. These mites feed on skin scales which have been “pre-digested” by mould fungi, and on other organic materials. Their excrement, the remains of their bodies and the fungi they live in symbiosis with can cause asthma and other allergic reactions, including “house dust mite allergy”.

Preventive measures and control

  • Change bedding often
  • Regular vacuum-clean and air beds and mattresses
  • Air bedroom and children’s rooms often and decrease the humidity
  • Use Insecticides against house dust mites

Larder Beetle

Dermestes lardarius and Dermestes peruvianus are barely distinguishable by their appearance. They are both around 6 to 10 mm long and have virtually the same colouring. Beetles and larvae are primarily blackish brown, and the common larder beetle also has a light rusty brown band across its wing cases. The females of both beetle species each lay up to 200 eggs on food. This means that in favourable conditions five to six generations of beetle can develop each year.

Both beetles and larvae are relatively sensitive to the cold.

An infestation of larder and hide beetles is usually identified by their hairy larval skins which are clearly visible. The larvae often occur in large numbers and destroy hides and leather by eating away at them from the inside, leaving them shabby and full of holes. Woollen textiles can also be infested. Damage can also occur in bales of tobacco, cotton reels, cork and asbestos when the larvae bore into them to pupate.

Preventive measures and controls

  • Larvae on the wall should be wiped off with a cloth or removed using a vacuum cleaner
  • Infested textiles should be brushed out, beaten, washed, cleaned or ironed
  • These pests can be destroyed by very hot or cold temperatures
  • Beetles on windows indoors should simply be moved outdoors
  • Insecticides to be used

The basis rule is:
Regularly air and thoroughly vacuum carpets etc in your home, taking care not to forget poorly accessible places

mosquitoDepending on the species mosquitoes can grow to 4 to 6 mm long. Only the females bite and suck blood, which they need for reproduction. The males do not bite.

Usually the mosquito larvae grow in stagnant (dirty) and shallow water. Moisture and heat speed up the developing cycle of the larvae.

Mosquitoes are mostly active in the time between dusk and dawn – on warm humid days in the afternoon as well. In the daytime they usually hide in moist shady places such as hedges and woodland, or in houses.

They are responsible for transmitting the commonest infectious diseases throughout the world.

Mosquito species such as Aedes, Anopheles and Culex are carriers of dangerous diseases such as yellow or dengue fever (Aedes), malaria, virus encephalitis, filariasis (Anopheles), meningitis and filaria (threadworm) diseases (Culex).

Preventive measures and control

  • Avoid stagnant water in and around your house
  • Use a mosquito net during the night, and mosquito or fly gauze in windows and doors
  • Use insecticides.
  • Use mosquito repellents on your skin.

mothThe clothes moth (Tineola bisselliella) is one of the most feared material pests. Its yellow-white larvae cause the actual damage to fabrics, furs and carpets. Above all clothing which has not been worn for some time is affected.

The clothes moth grows to about 4 to 9 mm long, and can easily be recognised from its shiny yellow front wings.

Another type of pest, the storage pest, is the food moth, such as the grain moth (Sitotroga cerealella), which attacks stores of food. Their larvae eat round holes in grains of wheat, rice and maize. The larvae of the lead-grey flour moth (Ephestria kuehniella) also feed on flour products. Besides this they soil and spin webs on large quantities of food. A single female flour moth can lay 200 eggs up to four times per year.

The infested food is covered in a coating of white dust, tastes bitter, and may harm the health of humans and animals.

Preventive measures and control

Clothes moths

  • Never leave clothing damp and/or uncleaned for a lengthy period in a cupboard.
  • Regularly vacuum-clean, brush or beat clothes.
  • Regularly vacuum-clean infested wardrobes, and as a preventive measure vacuum-clean thoroughly at least twice a year.
  • Lavender, cedar wood and ethereal oils are only of limited help. They may repel some of the moths, but they have no affect on the greedy larvae.
  • Use insecticides

Food moths

  • Never store flour, grain, dough and pastry in damp conditions
  • Thoroughly clean infested cupboards, including the shelves.
  • Use Insecticides

Common Name:
Roof/Black/Ship Rat

Scientific Name:
Rattus rattus

Adults with combined head & body length are 6-8″, Tail length 7-10″. Usual weight 150-250 gms but can grow to 340 gms. Fur is soft & smooth.

Colour is usually brown with black intermixed to gray to black above with the underside white, gray or black. Muzzle is pointed, Ears are large. Tail is scaly and uniformly dark, longer than head and body combined. The droppings of the adult rat are upto 0.5″ long spindle shaped with pointed end.

Roof rats reach sexual maturity in 2-5 months pregnancy lasts an everage of 22 days. The young are blind & naked at birth, with hair appearing in 7 days and eyes opening in 12-14 days. They are weaned at about 3-4 weeks. The average number of litters is 4-6 per year, Each containing an average live 9-12 months. They have poor vision & are colour blind. The roof rat requires 14-28 gms of food & about 30 ml of water each day, with water often coming from their food. This intake of food & water results in 30-180 droppings & approx 16ml of urine.

Roof rats are primarily nocturnal in habit and they are very cautious. They are constantly exploring their surroundings and shy away from new objects & change. As their name indicates, Roof rats prefer to nest in the upper part of structures, but may also be found under buildings occasionaly in basements and sewers.

Roof rats eat anything, but never fruits, vegetable and cereals. If they find that a particular food material proves disagreeable, they are quick to develop food/bait shynes.

The key to any rat control program is Pest Identification, Sanitation, Harborage Elimination & Rat Proofing the Building. Some important things to remember are: (a) Rats defecate where they spend most of their time. Use the droppings as an indication to concentrate the control effort. (b) Rats travel 100-150 ft for food/water along established paths. Look for rub/swing marks.

Control methods include Toxic/Non toxic Tracking Powder, Baits, Traps, Glue Boards along established pathways, Gassing (fumigating) of burrows.

Rice weevilSitophilus oryzae is only 3 mm long, but it can cause quite a lot of damage despite its small size. The blackish-brown rice weevil, which was inadvertently introduced from the tropics, can be identified by the four square-shaped orange markings on its wing cases.

The females like to lay their 100 to 200 eggs in cereal grains, but barley & pasta can also be infested. They breed particularly well in warm temperatures. They gnaw a hole in the cereal grain, lay one egg per grain and then seal the opening with a secretion. The egg develops into a larva and then into a pupa in the shell of the grain.

Depending on the temperature, the growth cycle takes one-and-a-half to six months. The beetle itself can survive without food for several months.

A cereal grain infested with the rice beetle looks completely normal from the outside. The larvae eat up the grains, leaving behind the empty shells. Infested cereals become warm and soon become musty, and subsequent pests can also cause additional losses.

Preventive measures and controls

  • Insecticides should not be used in food-storage cupboards or in the direct vicinity of food
  • Infested food should be removed and destroyed immediately
  • Thoroughly vacuum cupboards using the crevice tool of a vacuum cleaner, paying particular attention to cracks and crevices
  • Wipe out cupboards with a damp (never wet) cloth and allow to dry completely. Leave the doors open for a while
  • Store newly purchased food in sealed containers.

The basis rule is:
Store food in a cool, dry place

silver fishSilver fish (Lepisma saccharina) have inhabited the earth for over 300 million years. They depend on high atmospheric humidity, and so usually occur in bathrooms, washing basements and damp storage rooms and pantries.

The insects are silver in colour and 10 mm to 12 mm long, and lay their eggs in cracks and crevices. They thrive best in temperatures between 25° and 30° Celsius, and cannot reproduce in a cold and dry environment. These light-shy, nimble and wingless insects live for up to four years.

Silver fish only cause trouble in large quantities. They prefer food containing starch such as glues, book bindings, starched fabrics and photographs. But they also damage leather articles and synthetic fabrics by gnawing and eating holes. The foods they infest usually contain sugar. In bathrooms they feed on hairs, skin scales and dirt.

Preventive measures and control

  • Keep infested rooms cool and dry
  • Pour boiling water into bathtubs and sink drains
  • Vacuum-clean holes, crevices and cracks
  • Use insecticides


Four “castes” of a termite colony:
Worker: approximately one-forth of an inch long, light colored, wingless;
Soldier: elongated head with mandibles;
Supplementary Reproductives: wingless or very short, non-functional wings; light colored;
Primary Reproductives: winged, and darker than other members; caste most often seen by homeowners.

Live in colonies underground, from which they build tunnels in search of food; able to reach food above the level of the ground by building mud tubes; dependent on moisture for survival. Their main diet consists of Wood and other cellulose material.

Different rates of growth from egg stage to adult depend on individual species; one queen per colony, which can lay tens of thousands of eggs in her lifetime, but most eggs are laid by supplementary reproductives in an established colony.

Additional Information:
Termites rarely expose themselves to light. They Cause more damage to homes in U.S. than storms and fire combined. Termite Colonies can contain up to 1,000,000 members. Termites will sometimes eat away the wooden structures in a house leaving the paint work intact.

tickTicks are a problem as carriers of diseases throughout the world. They do not belong the insect species but are arachnids. In our latitudes there are about two dozen species, of which eight are of medical importance. Primarily the common castor-bean tick (Ixodes ricinus) is responsible for transmitting diseases to humans.

During their development ticks usually have to consume blood several times. To find a donor they settle on grass, fern or the underside of other leaves and bushes, and often wait for several months. If they detect a host, they drop on to it and find a suitable place to suck blood. On humans they prefer moist and warm areas such as the armpits or genital area. Their barbed proboscis unfolds after biting like an umbrella, to anchor the tick to the skin. If undisturbed feeding can continue for up to nine days. When full of blood the tick is several times larger.

The bite itself is usually unnoticeable, since pain-killing secretions are released. Often the site of the bite is only slightly red. Germs can be transmitted by the tick’s saliva, and frequently also by its excrement.

Ticks are carriers of tick borne encephalitis (a virus disease), which only occurs endemically in certain areas, and of the about 100 times more widespread borreliosis (a bacterial disease) in all regions with temperate climate.

Preventive measures and control

  • Covering clothing will protect from tick bites
  • Apply suitable repellents to uncovered areas of the body (lotion, cream, spray, pump spray)
  • The danger is less on pathways than when you go through undergrowth
  • After you have been in open countryside, examine your body for ticks
  • If seen in corners of beds, matresses etc, air matresses & beds.
  • Beds, matresses can also be sprayed with a insecticide to kill the ticks

To remove a tick proceed as follows:

  • grip the tick just above your skin
  • do not twist or squash it
  • do not put oil or alcohol on the tick
  • pull it out straight upwards

waspThe common wasp (Paravespula vulgaris) have black and yellow stripes and grow about 2 cm long. The common wasp can be identified from the vertical line on its head shield. The common wasp’s body is pointed. Its yellow colouring is not very vivid. Wasps live in nests made of a paper-like mass. The nests are only used for a year, and most of the insects die in October. Only the queens can survive through the winter, and this is why wasps are rare in spring. Most of the queen’s eggs develop into worker wasps, which can then become real pests in the late summer and autumn. It is important to realise that wasps themselves also catch plenty of insects, in particular harmful ones, and feed them to their larvae. A wasp colony can destroy up to two kilograms of insects per day. Nevertheless in autumn the community has already broken down. The wasps have only themselves to consider, there are no larvae, and their preferred food is carbohydrates.

Wasps can cause very painful stings that stay swollen for a long time and itch badly.

Preventive measures and control

  • Do not leave food uncovered
  • Never interfere with wasp nests, this is a job for a professional
  • Use insecticides against individual wasps