Here you will find information about the most common pests in Northumberland, including how to identify them, and where you might find them.
During May to September, wasps are extremely active. Their nests can be found in sheds, lofts, air bricks and bushes. If the nests are high up, in most cases they can be left and will die naturally at the end of the season. However, as the season draws to an end, the combination of the cool weather and a diet of fermenting fruit juices make them irritable and more likely to sting.
Young, fertilised queens survive the winter by hibernating, then emerging in mid-April to find a suitable site for nests. Common sites are loft spaces, cavity walls and sheds. Once found, she builds the first cell using chewed wood pulp and lays between 10 and 20 eggs, then feeds the resulting larvae until they emerge as workers. These workers then take over the tasks of enlarging the nest and providing food for larvae. The nest may potentially grow to the size of a football and house about 5,000 wasps but, in some cases, can be larger. In late summer, a generation of males and young queens emerge to mate, but the other wasps will gradually die off as the weather cools. The nest will not be used again.
Black ants are common in all parts of the UK and usually nest outdoors, favouring sandy or dry soils near house foundations and under paths. They are also increasingly found in cavity walls of properties. Worker ants are usually a dark brown-black colour, while queens are mid-brown and roughly 15mm long.
Worker ants invade buildings while foraging for food, particularly sweet foods. They enter through tiny holes under kitchen units, skirting boards or anywhere there is a gap big enough. When an ant finds a food source, other ants will soon gather, sometimes in large numbers. During late summer, flying male and queen ants can be seen swarming. They mate on the wing and can swarm for a few hours. They can be dealt with immediately using a suitable flying insect spray and can also be vacuumed, if occurring indoors.
Using sprays and powders in conjunction with gels and liquids will not be effective. You will kill very few ants, and not the whole nest.
The common rat is usually around 20 to 27cm long and weighs about 100-500g. They are commonly a brownish grey, with grey underneath. However, the colour varies. Rats have a single pair of upper and lower incisor teeth that continuously grow. This is why they gnaw, to prevent their incisors from growing too long and preventing them from eating.
Rats generally stay within 50m of their home, but can range up to 300m. They can move every two weeks or so, depending on food sources, and may travel several kilometres to seek food. They are mainly active at night and can be found in fields, gardens and sewers. Rats are sexually mature at three to four months old and produce six to 11 young.
If you see a rat in your garden and you feed birds, stop immediately, as this will encourage rats into your garden.
An average house mouse is roughly 6cm to 9cm long, with a tail of roughly eight to 10cm long. Their fur is a brownish grey, but can be lighter and they have excellent hearing due to their large ears. Mice reach sexual maturity 42 days after birth, so it is very important to deal with mouse activity as quickly as possible. Their life cycle is roughly nine to 12 months and the reproduce roughly eight times per year, with a litter size of five to six offspring.
Mice build nests in hard-to-find spaces, such as under floorboards, in wall cavities and in loft spaces. They are very inquisitive and like warmth, so check airing cupboards and behind cookers/fridges for signs of activity, such as droppings. They do not have the ability to control their bladder and constantly dribble urine that can contaminate food.
If you see a mouse in your garden and you feed birds, stop immediately, as this will encourage mice into your garden.
The adult bed bug is a flat, oval insect 5mm by 3mm and is reddish brown in colour. The female bed bug lays pearly white eggs approximately 1mm long. These are ‘glued’ into cracks and crevices in bed frames, furniture, wallpaper and anywhere that provides dark harbourage during daylight. They lay roughly 150 eggs that hatch within 10 to 20 days and reach adulthood in approximately nine weeks under reasonable conditions. This takes longer if the temperature is low. Adults live for up to 18 months, usually feeding weekly, but can survive for more than a year without blood.
Bed bugs do not fly, so they must crawl or be transported via clothing, luggage, or anything they can harbour in. They feed on blood, but can survive for long periods without feeding. While they are usually associated with poor, overcrowded and unhygienic conditions, they can be transported onto any premises. In domestic cases, most infestations are found in bedrooms, with hiding places being close to where the host sleeps – bed frames, mattresses etc. Bed bugs bite and feed on blood, which can cause severe irritation to some people. However, they are not known to carry disease unless, that is, you regard insomnia as such.
Cockroaches are large insects that range in size from 10 to 23mm with long antennae and two pairs of wings. The German cockroach is dark brown and smaller than the Oriental cockroach, which is black in colour. The German variety can climb smooth surfaces. The female cockroach produces up to eight purse-like egg cases monthly. These can contain up to 30 eggs and nymphs hatch within two to four weeks (6 to 12 for Oriental cockroaches). Their eggs are the size and shape of a small kidney bean and brown in colour. Their faeces looks like black pepper.
Cockroaches can carry food germs and are responsible for the spread of diseases such as dysentery and gastro-enteritis and they will feed on almost anything, including faecal matter. Food contamination occurs when the insect comes into contact with food, food preparation surfaces or through faecal contamination of food. Cockroaches spend their days hiding in cracks and crevices in a building, becoming more active at night. If a light is switched on they will scamper away to hide.
The threadlike larvae (1.5mm) hatch in approximately a week and thrive in dark, humid places. After two to three weeks, they moult twice and grow to 5mm long and spin their cocoons for pupation. Fleas formed in cocoons may ‘overwinter’ (or lay dormant), but emerge by the stimulation of vibration, usually of the host. Therefore, attacks sometimes take place when a property has been left empty. In favourable conditions, the life cycle is normally complete in four weeks. Fleas can only lay eggs after taking blood from a host animal.
Adult fleas live exclusively as parasites of warm-blooded animals, like cats and dogs. Cat fleas are responsible for 75% of all flea infestations. Cat and dog fleas will feed from humans when there are no animals around, but this is not their first choice. Flea eggs are 0.5mm long, pearly white, oval and slightly sticky, generally found on the hair, bedding or clothing of the host.
The European mole is between four to six-and-a-half inches long with a tiny tail of three quarters of an inch. It weighs three to five ounces and has small eyes and ears. Moles are practically blind and have poor hearing but make up for it with their excellent sense of smell. Their fur is short, dense and black and can lie at any angle, meaning it can go backwards and forwards through its tunnels. A mole’s diet primarily consists of earthworms and other small invertebrates found in soil, as well as a variety of nuts. The mole runs are, in reality, worm traps as the mole, when sensing a worm fall into the tunnel, quickly runs along to kill and eat it. Their saliva contains a toxin that can paralyze earthworms, so they can store their prey for later consumption.
Moles are solitary creatures and spend the majority of their life spans alone. Usually, they only associate with others during mating, or when a mother raises her young. They live underground and their main home consists of a single central chamber, with many connected tunnels.
Various over-the-counter products can be obtained, but are limited to their success rate.
Booklice are soft-bodied insects, yellowish brown in colour and rarely exceed one to 2mm in length. Some species have two membranous wings, although in many species the wings aren’t present. While they are common, they are harmless and do not cause any damage or destruction.
Occasionally, especially during autumn, people find their food cupboards have become infested by booklice. They are often discovered in flour, milk powder, sugar or any dried food. They dislike light and are found in folds in packaging and cracks and crevices in cupboards.
Infestations are not caused by poor hygiene and are as common in new homes as they are in older properties.
Although they look like insects, woodlice are in fact crustaceans related to crabs and lobsters. It is thought there are roughly 3,500 species of woodlice worldwide, with 35 to 40 being found in the British Isles. Woodlice are sometimes called pill bugs. The pill woodlouse gets its name from being able to roll up into a ball. Common woodlice live for three to four years and their main predators are centipedes, toads, shrews and spiders.
Most woodlice are found on land, but their ancestors used to live in water. Therefore they still breathe through gills. Woodlice eat rotting plants, fungi and their own faeces. They expel waste by producing ammonia, which passes through as gas. After mating, females carry their fertilised eggs in a small pouch under their bodies. When the young hatch, they stay in the pouch until they are big enough to survive alone.
Silverfish grow to about 12mm in length and, as the name implies, are silver-coloured and glisten. The female silverfish is believed to lay about 100 eggs, either single or in groups in crevices or cracks and are ‘glued’ to the surface as they are laid. They are small and white, but soon turn brown. Hatch time varies from two to eight weeks, depending on the temperature and humidity of the breeding site. Newly hatched, they are about 2mm long and the time they take to reach maturity varies from a few months to over a year, depending on their surroundings.
Silverfish are found in moist areas such as kitchens, bathrooms and basements. They can also be found in books and paper, slightly damp cupboards, behind skirting boards and loose wallpaper. Silverfish are nocturnal and move very rapidly when disturbed. They feed mainly on small food particles and wallpaper paste. They attack gums and glues of bookbinding, feeds on fragments of dead insects and may also eat textiles. The presence of silverfish is an indication of damp conditions. This may be a warning that repairs are needed. Another common problem is condensation, sometimes caused by drying washing indoors, or by cooking.
Adult wharf borers are narrow, flattened insects approximately 1cm long. When viewed from above, the main body varies from brown to a rusty colour, covered in very fine yellow hairs. The tips of the wings are generally black, along with the eyes, legs and underside. The antennae of the adult are about half as long as the length of the body. Mature larvae are two to three times longer than the adults and are a light brown to cream colour covered in very fine brown hairs. The mandibles (mouthparts) of the larvae are dark brown. Larvae have three sets of long legs located on the thorax and two leg-like appendages on the third and fourth abdominal segments. The life cycle of a wharf borer from egg to adult usually takes about one year, although in cooler locales this may take longer.
Wharf borers are found throughout much of the United States and Canada and have been introduced to Europe, presumably through commerce. Because they are found in moist wood, they are mainly associated with coastal areas, lakes, rivers, estuaries and waterways. They have been found in diverse places such as wharf timbers, crawlspaces or any wood with high moisture content, subject to decay. Adults are usually noticed as they emerge from wood, and this can take place at any time, but are most commonly found in spring and summer. Females deposit eggs and the larvae tunnel into wood, growing and producing long, elaborate tunnels.
They are harmless to man, so treatment is rarely necessary. However, the application of a suitable insect spray or powder should prove effective.
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