Description: Bed bug adults are reddish-brown, 4 to 5 mm long and 1.5 to 3 mm wide before feeding. Their flat shape enables them to readily hide in cracks and crevices. Engorged adults tend to be swollen and dull red. The eggs are white, oval, about 1 mm long and covered in a sticky film which allows them to adhere to surfaces. A newly hatched nymph is almost colourless whereas engorged nymphs are reddish and swollen.
Biology: Although humans are the preferred host, bed bugs feed on many warm-blooded animals. Bed bugs usually hide in cracks or mattresses during the day and emerge at night to feed. They inject saliva as they feed and allergic reaction to this substance often causes slightly delayed swelling, itching and burning. Under favourable conditions, each female lays 200 to 500 eggs and these hatch in around 10 days. Adults often survive up to 2 months without food, but under certain circumstances can live 12 months or more without feeding.
Control: The first step to dealing with bed bugs is to locate all of their hiding places. Furniture, fittings and even crevices in wallpaper must be inspected carefully for bed bugs, even to the point of dismantling beds etc for easier inspection and possible treatment. Applications are best done as a "crack and crevice" treatment to known or potential harbourages, as well as using a broad band residual insecticide through a coarse sprayer or as an Ultra Low Volume insecticide for the rest of the room.
Description: Book lice are small (1-2mm), soft bodied and wingless insects. They can be pale yellow, straw to dark brown and black in colour. They have a flat abdomen, biting mouthparts and poor eyesight.
Biology: Book lice are widespread in warehouses, found on many wooden pallets and packaging especially if stored in damp warehouses. Generally only a nuisance when in significantly large numbers. They can lay up to 200 eggs over a three day period. The book lice eggs incubate for one or two weeks. The nymphs have three to eight moults before they become adult book lice. The preferred environment is 20°C-25°C and a relative humidity of 70% but will develop as low as 10°C. They need a damp environment for successful growth, therefore high humidity. Book lice typically live for six months. Book lice tend to be found seasonally between April and November.
Control: Book lice are often found on packaging and palletised stock in warehouses. In these situations it is not possible to treat these insects with a contact insecticide. The only course of action is for the stock to be fumigated with a suitable gas. Book lice usually feed on the micro fauna growing on the surfaces of paper and cardboard, one solution is to keep the stock dry and keep the humidity low in the warehouse. Wooden pallets are often the culprit allowing cross infestation from stock to stock. Pallets can be sprayed of dipped with residual insecticide prior to use. Treatment of a warehouse or stock room with a contact insecticide where possible is recommended. Crawling insect monitors can be sited but are little use for control.
Brown House Moth
Description: This species is found throughout the United Kingdom. Brown moth with dark spots approximately 10mm in length, wing span 15 to 26mm. The wing tips have a hairy/feathery appearance and the wings themselves have dark brown spots (although these can easily be rubbed off).
Biology: The larvae of these insects can cause considerable damage when they feed on articles that contain wool, mohair, fur, hair, feathers and other products of animal origin. The brown house moth will also feed on other organic debris including dried or mouldy food waste. The female lays 100 to 600 white eggs on the surface of fabrics that can hatch into larvae from 8 to 110 days. The period of larval development is 71 to 145 days, during which time the larvae actively feed on fabrics etc.
Control: Locate the source of infestation before treatment. Spilled foodstuffs and other waste material should be cleaned up; where old bird's nests are present they should be removed and destroyed. Where necessary an approved insecticidal powder can be applied to wall/floor and ceiling floor junctions and around carpet edges, both sides of carpets should be treated. Insecticidal polishes may be useful for treating woodwork and flooring. If the infestation is present in a loft or roof space, the structure should also be treated with a residual insecticide and/or a space treatment (ULV - Ultra Low Volume, smoke etc).
Cat and Dog Flea
Description: Adult Cat fleas/Dog Fleas are 2 to 3 mm in length and generally of a brown appearance. They have a thin, laterally flattened body and large hind legs which allow them to jump onto passing hosts. The larvae of both species are nearly twice as long as the adults.
Biology: Flea eggs are about 0.5mm long, oval, pearly-white in colour and laid indiscriminately in the fur or feathers of the host or in its nest or bedding. A typical female flea may lay 200 eggs over a period of five days. They will hatch in a further 4 to 12 days, depending on the temperature and humidity. The larvae thrive in dark, humid places such as animal bedding and carpet fluff, and feed on organic debris and adult flea excrement. Animal bedding may support a flea population of 8000 immature and 2000 adult forms.
Control: Where very high populations of fleas are present, a single application of insecticide may not be sufficient, as even a 99% kill rate can still leave sufficient survivors to form the basis of a new infestation. In such cases, additional treatments will need to be carried out until the infestation is eradicated. All floors and upholstered furniture should be vacuumed to remove animal hairs, organic debris, flea eggs and pupae. Dispose of vacuum bag in an outside bin. Any cats and dogs should be treated for fleas with an insecticide recommended for this purpose and pet bedding should be destroyed or washed. All floor areas should then be treated with a residual insecticide or a desiccant spray from skirting board to skirting board.
Description: Cluster flies are found throughout the United Kingdom. At about 9mm long, the cluster fly is slightly larger than the common house fly. The thorax is dark olive grey, with fine golden hairs which can easily be rubbed off. There are no distinct lines or stripes behind the head and the abdomen has irregular light and dark grey areas.
Biology: The female lays eggs in the soil near the burrows of earthworms. The tiny maggots that hatch from the eggs seek out earthworms to feed upon. As cold weather progresses, adults seek protected places to spend the winter, particularly during September and October (activity can often be noted again in early spring). In many cases the flies seek shelter within walls, roof spaces and lofts, usually returning to the same building year after year and often favouring south facing buildings.
Control: Complete control of cluster flies is almost impossible since the over wintering adults are concealed in walls, lofts, etc. Adults are sluggish enough in the winter to be picked up with a vacuum cleaner. Smoke and ULV(Ultra Low Volume) treatments will provide a knock-down in lofts, but as with any loft treatment, always check first for the presence of bats before proceeding.
Description: The cockchafer is often mistaken for a cockroach due to its size and shape. Found throughout the UK they are more common in the south, often seen flying at dusk from May to July.
Biology: The cockchafer has a three year left cycle. After mating the female digs about 20 cms into soil to lay her 10 to 20 eggs. Once the eggs hatch after around 21 days, the larvae remain in the soil for a further two years feeding on roots.
After pupation, the adult beetles emerge in October, but remain in the soil to the following spring. Although harmless, both adults and larvae can cause damage to plants and crops.
Control: Not considered to be of public health importance. However, control can be achieved by applying a broad-spectrum residual insecticide to entry points around buildings and/or proofing.
Common Clothes Moth
Description: Adults can reach up to 7mm in length and have a wingspan of 10 to 20mm. The moths are a light, shiny gold or silvery colour, with a tuft of reddish hairs on the head.
Biology: Clothes moths rarely fly to lights at night and instead prefer darkness, such as a closet or storage chest. Any clothes moths fluttering around the house are probably males, because females travel by running, hopping, or trying to hide in the folds of clothing. The female lays 100 to 150 white eggs on the surface of the fabric which will hatch into larvae in approximately 5 days. The period of larval development is usually 6 weeks, during which time the larvae actively feed on the fabric, however this can take considerably longer under cooler conditions.
Control: Treatment is similar for all the textile moths. Examine cupboards and stored goods for larvae cases, moths, and damage to locate the source of infestation before treatment. Once the source has been identified treat/destroy as necessary. A residual insecticide can then be applied to wall/floor and ceiling/wall junctions and around carpet edges, back of empty wardrobes. If the infestation is present in a loft or roof space then the area can also be treated with a residual insecticide and/or a space treatment (ULV, smoke etc). Clothing and bedding should not be sprayed with insecticides.
Description: Adults are about 2mm long, very hairy and with almond shaped wings. They are often mistaken for small moths since the wings are held roof-like over the body when at rest. They are weak flies and often appear to be hopping or jumping.
Biology: They are often associated with moist, highly organic such as sink drains, sewage works, storm drains, dung and rotting vegetation. Each female can produce about 100 eggs, and development can be completed in two weeks.
Control: If found in abundance, a careful search for the larvae breeding areas should be made and the necessary measures taken. Any remaining adult flies may be controlled by use of residual insecticide or ULV treatment.
Fruit and Vinegar Flies
Description: Fruit flies are very common in homes, restaurants and supermarkets. The adult flies are very small, about 3mm long and have red eyes. Body colour is usually a light yellow to tan colour and the abdomen is grey underneath. A common characteristic of the flies are distinctive red eyes.
Biology: Female fruit flies lay their eggs on the surface of rotting fruit, fermenting juices, soured milk etc. Fruit fly larvae feed on the yeast organisms and fungi growing in the fruit and vegetable materials. Through their feeding efforts, they soon turn their food into a semi-liquid mess and given their biology, they are a common pest in pubs and commercial kitchens.
Control: Should the flies become abundant, a search for the larval breeding areas should be made, and the necessary housekeeping or maintenance measures taken. Any lingering adult flies may be controlled by the use of a Pyrethrum based insecticide or ULV(Ultra Low Volume) treatment. Stagnant water may be treated with Bti (bacillus).
Description: The fungus gnats are flies about 4mm in length and are small, black with a very distinctive pointed abdomen.
Biology: The Gnats are often found in offices and domestic environments; usually associated with stagnant water in plant pots and displays. Occasionally they can be associated with bath and sink overflows and stagnant water that may have resulted from leaks. Sometimes the Gnats breed in condensation drip trays used in air conditioning systems. The females are parthonogenic (not needing males to breed). Larva can be supported by material in plant pots especially if a plant or bulb has died and is decomposing. The pupa hatch in this medium.
Control: This is often difficult to achieve, generally you should isolate plants likely to support the flies and ensure that they are in good order before being re-introduced. An horticulturist can carry out a treatment in the void below the plant. Sometimes extreme action has to be taken because of complaints, in these cases the area affected is treated with a fog or mist using ULV (Ultra Low Volume) insecticidal material. Residual spray treatment is not often effective and tends to make office inhabitants relieved rather than having any toxic effect on the insects.
Description: The garden ant can be found all over the United Kingdom. Typical worker ants are 4 to 5mm long of a brown/black colour with elbowed antennae and biting mouth parts. The queen tends to be much larger at about 10 to 15mm.
Biology: Garden ants usually nest outdoors in lawns, flower beds, beneath paving stones and at the base of walls. Premises are usually invaded by worker ants foraging for food, especially sweet foods. During summer, winged females (queens) and males leave the nest on a warm afternoon and take flight. During this flight, which may only last 2 to 3 hours, the ants mate. The formation of a new colony starts with a mated winged female digging into the earth to overwinter and start a new colony in the spring.
Control: If possible, trace the trail of worker ants to the nest. If the nest can be exposed, and it is safe to do so, apply an insect powder labelled for that use. If it is not possible to trace the nest, use a residual insecticidal spray to treat outside the building. Special attention should be paid to likely entry points such as door frames, air bricks and waste pipes to create an insecticidal barrier. In addition, use of gels and liquid feeding baits can help with longer term control.
Description: Adults are about 17mm long and light brown except for the shield behind the head marked with two dark stripes, which run lengthways on the body. The nymphs are wingless and nearly black with a single light stripe running down the middle of the back. Each capsules are light tan.
Biology: Egg cases are carried by females until just before hatching and each female may produce four to six cases in her lifetime, each containing 30 to 40 eggs. Eggs hatch within 20 to 30 days, and nymphs develope in 40 to 125 days. Females live up to 200 days (slightly longer than males). The German Cockroach produces more eggs and has more generations per year (three to four) than any other cockroach, and only a few individuals are needed to develop into troublesome infestations.
Control: Use of monitoring traps to physically catch and determine the extent of an infestation, along with insecticide gels and well targeted use of residual insecticides where appropriate is recommend. Night time inspections may be necessary in difficult to control situations.
Indian Meal Moth
Description: The moth has a 14 – 20 mm wingspan and is easily identifiable by the distinctive colouration of the forewing. The first third towards the head is a cream or grey colour and the remaining part of the wing a copper or reddish brown. The larvae may be a yellowish or pale green colour depending upon the foodstuff eaten and have a light brown head. The pupa is a yellow brown colour.
Biology: The adults will lay anything between 150 to 300 eggs in foodstuffs to enable to the larvae to feed. The eggs hatch in approximately 2 – 8 days. The larvae contaminate the foodstuffs by spinning silk webbing, direct damage by eating as well as frass (faeces). Larvae go through a stage of 4 – 7 moults before pupating, with the time from egg to adult taking anything up to 8 – 10 months depending upon temperature.
Control: Infested material must be removed, destroyed or where possible fumigated. The walls, floors and wall to floor junctions are treated with a residual insecticide applied by hand held compression sprayer, with the area treated with a ‘space spray’ application of insecticide applied by a ‘fogging’ machine. The area needs to be vacated for a specified period of time before being allowed to re-enter.
Description: Adult larder beetles are about 7 to 9mm long with an oval shaped body. They are dark brown, with a broad, pale yellow, black-spotted band across the front portion of the wing covers. There are six black dots on this band, three on each wing cover, arranged in a triangle. The underside and legs are covered with fine, yellowish hairs. Other dermestes beetle species include D. peruvianas (uniformly dark) and D. maculatus (black with patches of white hairs).
Biology: Females each lay up to 200 eggs, which hatch in 12 or more days. Larvae prefer spoiled ham, bacon, dried beef and other meats. Larvae either bore into this meat or wander away to bore into wood, books and even metals such as lead and telephone cables to pupate. The life cycle requires a minimum of 40 to 50 days.
Control: The first step is to trace the source of the infestation. In domestic situations or industrial kitchens, an integrated programme of cleaning and spraying with a residual insecticide (paying attention to all cracks and crevices), will control most infestations.
Lesser House Fly
Description: Adults are 6 mm long with a 12 mm wing span. They have a grey thorax with three longitudal stripes, less pronounced than the common house fly. The base abdomen has an extensive yellow patch. At rest, wings are folded back; venation shows 4th vein extending straight to wing margin. They have an erratic flight pattern and are often seen flying in large numbers around indoor light fittings. The Lesser House Fly is more tolerant of cool conditions than the Common House Fly.
Biology: When eggs are laid they are about 1 mm long and they hatch with 24 to 48 hours. Larvae development is 8 days and they have 3 skin moults. They are 6 mm when fully grown. Life cycle to adult takes about 3 weeks and they breed mainly in poultry manure.
Control: Good hygiene is essential to limit breeding sites and food sources. Entry of flies into buildings can be prevented by proofing doors and windows. Spraying alighted surfaces with a residual insecticide will also have some effect. Application of larvacides is also a good method of control within agriculture, helping to control infestations at source.
Lesser Mealworm Beetle
Description:Description: Adults are up to 6mm long and dark brown to black. Adults and larvae are often found in floor litter where they feed on poultry feed, dried bird droppings and bird carcasses. In high numbers, as well as being a vehicle for disease, they can cause considerable structural damage as larvae will often tunnel into timber and insulation material in order to pupate.
Biology: After mating, the female has the ability to lay over 2,000 eggs, but the average is 200 to 400. Eggs are laid in batches and hatch in 4 to 5 days under typical room temperatures. The larval period can be as short as 8 weeks and following a 5 to 10 day pupal stage, the adult emerges. The average time from egg to adult takes about 80 days and the adults can live from three to twelve months.
Control: Effective litter management can slow the development of these beetles and reduce the chances of having excessive build-up of numbers. The poultry houses can be treated with residual insecticides (ideally after cleaning) but often not in the presence of birds (check label instructions). In non-poultry situations, infested goods and debris should be removed, followed by spraying with a broad spectrum residual insecticide.
Description: Usually dark reddish brown in colour the adults are about 25mm long and the immature cockroaches (nymphs) resemble adults except they are wingless.
Biology: Unlike other pest cockroaches, Oriental's can not climb up smooth surfaces. They generally live in moist areas but can survive in dry areas if they have access to water. Adult cockroach can live up to one year, during which time females produce up to 150 young. The cockroach prefers to feed on starchy foods but will adapt to survive.
Control: Use of monitoring traps to physically catch and determine the extent of an infestation, along with insecticide gels and well targeted use of residual insecticides where appropriate is recommend.
Description: A small ant of tropical origin. The workers are only 2mm long, the queen, 5mm long. Both are yellow in colour. The ant has a double segmented waist and a darkened tip to the abdomen.
Biology: In temperate climates it is an indoor species associated with large facilities such as hospitals, prisons and block of flats. Unlike some other ant species, the queen can be replaced by other queens. This is an important feature to bear in mind, as new queens can be produced when needed resulting in colonies that can split.
Control: The use of general residual treatments is often not effective as they may cause the nest to fragment. Baiting may be effective if the active ingredient is slow acting. Although modern treatments are very effective, there may be cases where they don't work.
Description: Phorid Flies are in the small category of flies measuring 3mm in length, including the wings. The most prominent feature of this fly is the humpbacked shape of its thorax.
Biology: The Phorid fly breeds and feeds mostly on decaying organic matter. Their reproductive potential is tremendous and a great number of them can appear in a short time. The life cycle from egg to adult can be completed in just 14 days.
Control: The key to controlling them is to locate and eliminate their breeding sources. A space spray using an aerosol will provide a rapid knock down for small infestations.
Description: Adult mites are 0.8mm long and about 0.4mm wide. The colour can vary to grey to white but they often appear to be red depending on the blood content. They feed on the host bird at night before returning to the cracks and crevice they inhabit.
Biology: The females lay their eggs after a blood feed - hatching into 6 legged larvae after 3 days and an 8 legged nymphal stage which takes a further 4 to 5 days.
Control: Mite control is a challenge as they can survive several months without a feed, are difficult to treat with the poultry present and will survive cleaning a disinfectants. Ideally, the poultry sheds need to be cleaned when empty and residual insecticide applied.
Tobacco and Biscuit Beetles
Description: The Biscuit Beetle, also know as the Drugstore Beetle is 2-4mm in length, reddish brown in colour. Its head is tucked below the thorax, it has a pair of loose three-segmented club antennae, and the wing covers are finely ridged. The body is covered in very fine short yellowish hairs. Biscuit Beetle larvae are white with a yellow head and the body is fleshy and curved. This beetle is very similar in appearance to the Tobacco Beetle and Furniture Beetle.
Biology: Often reported in bakeries, especially in bread coolers. Also found in warehouses, restaurant and hotel stockrooms. It is a pantry pest and can be found in stored food samples in labs and test kitchens. 20-100 eggs are laid in food material,hatching one to two weeks later. The larvae after hatching are only 0.5mm in length. Larvae chew through foodstuff and packaging making tiny holes. The larvae have four moults until fully grown at 5mm, this takes up to five months. The cocoon is formed in the food material and is covered with tiny food particles. Adult biscuit beetles hatch after about two weeks. The lifestyle completes in about 200 days at 17°C, but only 70 days at 28°C. Adults live for six to eight weeks and do not.
Control: The infested stock should be removed for disposal and the area cleaned and vacuumed if possible. The area should be treated with an residual insecticide. If in certain circumstances the insects are flying, then fogging/misting treatments can be carried out with ULV (Ultra Low Volume) insecticide. Install crawling insect monitors and if sited keep a check on the catch tray contents of fly killers.
Warehouse/Cocoa or Tobacco Moth
Description: A small moth, the caterpillars of which cause considerable damage to stored food products. As the name suggests it commonly attacks tobacco and cocoa, as well as grains, nuts, dried fruit and many other stored products. Adults are up to 10mm in length with greyish-brown wings and have dark double bands at the top and base of the wings (although these are frequently rubbed off). Similar in appearance to the Tropical Warehouse Moth where the wing markings are often less distinct (and the adults are less tolerant to temperature variances).
Biology: Up to 200 eggs are laid. There is usually only one generation per year, although under ideal conditions the life cycle can be as brief as 12 weeks.
Control: Controlling this pest requires careful inspection of all stored cereal foods and machinery, discarding the heavily infested material and cleaning away any debris. Where the infestation is extensive; a residual insecticide can be applied to the cracks and crevices around wall/floor and ceiling/floor junctions. Infestations of this moth in food processing facilities can be controlled by removing and destroying infested products and by using intensive cleaning and fumigation as required.
Yellow Mealworm Beetle
Description: The yellow mealworm beetle (Tenebrio molitor) is quite a large insect up to 15mm long with even longer larvae. They are commonly for sale as pet and bird food and are widespread throughout the UK.
Biology: The female mealworm beetle lays up to 500 eggs, often in batches, over a period of weeks. These eggs have a sticky exterior which helps to hide them as they become covered in dust and debris. Some two weeks or so later the larvae hatch and start feeding on any suitable food material. As a slow breeding species the larvae will moult several times and may grow up to approximately 28mm in length.
Control: In order to control mealworm beetles it is important to first identify the source of the infestation, which will not usually involve more than ten or so beetles and then treat the infestation. Removing the food sources such as old birds nests and food debris will help to control the beetles. Crawling insect sprays available from the local chemist, garden centre or hardware store may control small infestations. Large infestations may require a professional treatment to be carried out.