American cockroach
The insect can travel quickly, often darting out of sight when someone enters a room, and can fit into small cracks and under doors despite its fairly large size. It is known to be very mobile, and it also has wings which allow it to be quite a capable flier. It prefers warmer climates and is not cold tolerant; however, it may survive indoors in colder climates. It does well in moist conditions but also can tolerate dry conditions as long as water is available. Back to Top

Argentine ant
These tiny ants will set up quarters in the ground, in cracks in concrete walls, in spaces between boards and timbers, even among belongings in human dwellings. The worker ants are only about 1.6 mm (1/16th inch) long. They can easily squeeze through cracks and holes no more than 1 mm (0.040 inch) in size. Queens are two to four times the length of workers. They are attracted by electrical currents and are known to have caused damage to air conditioners, heat pumps, telephone junction boxes, traffic lights, gasoline pumps, and so on. When they become lodged or electrocuted between the contacts of relays, it damages the contacts and causes the equipment controlled by the relay to malfunction. Back to Top

Bedbugs
Bedbugs are generally active only at night, with a peak attack period about an hour before dawn, though given the opportunity; they may attempt to feed at other times of day. Attracted by warmth and the presence of carbon dioxide, the bug pierces the skin of its host with two hollow tubes. With one tube it injects its saliva, which contains anticoagulants and anesthetics, while with the other it withdraws the blood of its host. After feeding for about five minutes, the bug returns to its hiding place. The bites cannot usually be felt until some minutes or hours later, as a dermatological reaction to the injected agents. Although bedbugs can live for up to 18 months without feeding, they typically seek blood every five to ten days. Bedbugs are often erroneously associated with filth. They are attracted by exhaled carbon dioxide, not by dirt, and they feed on blood, not waste. In short, the cleanliness of their environments has no effect on bedbugs. Their numbers may be reduced temporarily by vacuuming, but will recover and require vacuuming again. Back to Top

Black widow spider
As with many poisonous creatures, the brightly colored markings serve as a warning to predators. Black widow spiders typically prey on a variety of insects, but occasionally they do feed upon woodlice, diplopods, chilopods and other arachnids. Although their venom is extremely potent, these spiders are not especially large. Compared to many other species of spiders, their chelicerae are not very large or powerful. Back to Top

Boxelder bug
These insects feed on the softer plant tissues, including leaves, flowers, and new twigs. Unless the population is exceptionally large, the damage to plants is minimal. During years when their population soars, they can damage useful shade trees.
After summer, they can become household pests. The adult-stage insects seek wintering hibernation locations and find their way into buildings through crevices. They remain inactive inside the walls while the weather is cool. When the heating systems revive them, they begin to enter inhabited parts of the buildings. They have a proboscis for feeding which could potentially pierce human flesh and cause slight irritation. However, this is unlikely. Their presence is nonetheless often considered an undesirable nuisance. When crushed, they give off an offensive odor; they are among many unrelated insects commonly called "stink bugs." Back to Top

Brown recluse spider
The brown recluse spider is a venomous spider. It is brown and usually has markings on the dorsal side of its cephalothorax, with a black line coming from it that looks like a violin with the neck of the violin pointing to the rear of the spider resulting in the nickname "fiddleback spider" or "violin spider". Coloring varies from light tan to brown and the violin marking may not be visible. Since the "violin pattern" is not diagnostic, and other spiders may have similar marking. Differing from most spiders, which have 8 eyes, recluse spiders have 6 eyes arranged in pairs (dyads) with one median pair and 2 lateral pairs. Only a few other spiders have 3 pairs of eyes arranged this way (e.g., scytodids), and recluses can be distinguished from these as recluse abdomens have no coloration pattern nor do their legs, which also lack spines. These spiders frequently build their webs in woodpiles and sheds, closets, garages, and other places that are dry and generally undisturbed. Unlike most web weavers, they leave these webs at night to hunt. Back to Top

Bumblebee
The bumblebee feeds on nectar and gathers pollen to feed its young. These creatures are beneficial to humans and the plant world alike, and tend to be larger and furrier than other members of the bee family. Queen and worker bumblebees can sting, but the sting is not barbed like that of the honeybee, so they can sting more than once. Back to Top

Carpenter ants
Nesting in damp locations, carpenter ants prefer to excavate wood that has been damaged by water. From their nests in the beams, floors or walls, they scavenge a house for food crumbs and insects. Carpenter ants may occur in several colors, although the most important species are black. One of the largest members of the ant family, carpenter ants take their name from their habit of chewing passageways (called "galleries") inside wood. They live in these galleries and make excursions, most often at night, to hunt for food and water. These ants often set up satellite colonies inside homes from parent colonies located outside in a tree or landscape timber. Carpenter ants nest in both moist and dry wood, but prefer wood which is moist. Consequently, the nests are more likely to be found in wood dampened by water leaks, such as around sinks, bathtubs, poorly sealed windows/ door frames, roof leaks and poorly flashed chimneys. Nests are especially common in moist, hollow spaces such as the wall void behind a dishwasher, or in a hollow porch column. Since there often will be no external signs of damage, probing the wood with a screwdriver helps reveal the excavated galleries. Another technique for locating hidden nests is to tap along baseboards and other wood surfaces with the blunt end of a screwdriver, listening for the hollow sound of damaged wood. If a nest is nearby, carpenter ants often will respond by making a “rustling" sound within the nest, similar to the crinkling of cellophane. Carpenter ants are active indoors during many months of the year, usually during the spring and summer. When ants are active in the house during late winter/early spring (February/March), the infestation (nest) is probably within the household. When carpenter ants are first seen in the spring and summer (May/June), then the nest is likely outdoors and the ants are simply coming in for food. The natural food of the ants consists of honeydew from aphids, other insects, and plant juices, but they will readily forage for water and food scraps within the house. Back to Top

Crickets
Crickets prefer to live outdoors, but will move inside when environmental conditions become unfavorable. Their method of entry into buildings includes open doors and windows as well as cracks in poorly fitted windows, foundations, or siding. Crickets chirp at different rates depending both on their species and the temperature of their environment. Most species chirp at higher rates the higher the temperature is (approx. 60 chirps a minute at 13ºC in one common species; each species has its own rate). The relationship between temperature and the rate of chirping is known as Dolbear's Law. In fact, according to this law, it is possible to calculate the temperature in Fahrenheit by adding 39 to the number of chirps produced in 15 seconds by the snowy tree cricket common in the United States. Back to Top

Deer mice
This mouse is a known carrier of Hantavirus, which can be transmitted to humans. White-footed mice live in a wide variety of habitats but are most abundant in warm, dry forests and brushlands at middle elevations. They are the most abundant small rodent in mixed forests in the eastern United States and in brushy areas bordering agricultural lands. Deer mice do not hibernate. Their winter activities may include taking up quarters in a pile of logs, from which they venture nightly in search of food. The tracks of one mouse led from the logs to one bush after another in a wandering fashion to the edge of a bare field some 100 m distant and then back to the log pile. Deer mice breed in every month of the year, with peaks in the periods from January through April and from June through November. Back to Top

Drain flies
The adults have long antennae and the wings are leaf-shaped, either slender or broad, with the most elementary wing venation of any Diptera, having little more than a series of parallel veins without crossveins. Adult Psychodidae are mostly nocturnal and associated with damp habitats (non-phlebotomines). The larvae live in aquatic habitats (often with low oxygen), including bathroom sinks - they are common nuisance pests in bathrooms. Back to Top

Earwig
They feed on other insects, plants, ripe fruit, and garbage. Plants they feed on typically include clover, dahlias, zinnias, butterfly bush, hollyhock, lettuce, strawberry, sunflowers, celery, peaches, plums, potatoes, roses, seedling beans and beets, and tender grass shoots and roots; they have also been known to eat corn silk, damaging the corn. Typically they are a nuisance because of their diet, but normally do not present serious hazards to crops. Some tropical species are brightly colored. Occasionally earwigs are confused with cockroaches because of the points on the end, the long antennae. Earwigs are most active at night and can be seen patrolling household walls and ceilings. Interaction with earwigs at this time results in a defensive free fall to the ground below, and the subsequent scramble to a nearby cleft or crevice. Earwigs are also drawn to damp conditions. During the summer they can be found around sinks and in bathrooms. Earwigs tend to gather in shady cracks or openings or anywhere they can remain concealed in daylight hours. Picnic tables, compost and waste bins, patios, lawn furniture, window frames or anything with minute spaces can potentially harbour these unwanted residents. Upon gaining entry to the basement and living areas of the home, earwigs can easily find cover in undisturbed magazine and newspaper piles, furniture/wickerwork, base boards, carpeted stairways, pet food dishes, and even inside DVD cases. Earwigs are inclined to take risks and are exploratory creatures but are overly unaware of the consequences and will often find themselves trapped in poison baited cups or buckets of soapy water. There is no evidence that they transmit disease or otherwise harm humans or other animals, despite their nickname pincher bug. Back to Top

Flea
Fleas are external parasites, living by hematophagy off the blood of mammals and birds. In most cases, fleas are just a nuisance to their hosts, but some people and some animals suffer allergic reactions to flea saliva resulting in rashes. Flea bites generally result in the formation of a slightly-raised swollen itching spot with a single puncture point at the center. The bites often appear in clusters or lines, and can remain itchy and inflamed for up to several weeks afterwards. Fleas can also lead to hair loss as a result of frequent scratching and biting by the animal, and can cause anemia in extreme cases. Back to Top

Fruit fly
Fruit flies are of major importance in agriculture. Some have negative effects, some positive. Various species of fruit fly cause damage to fruit and other plant crops. Most fruit flies lay their eggs in plant tissues, where the larvae find their first food upon emerging. Back to Top

Hobo spider
Hobo spiders sometimes build their webs in or around human habitations. Although this species of spider has a reputation for aggressiveness, they will normally avoid contact with humans. Most bites occur when the spider is accidentally crushed or squeezed by a human. The spider's venom is strong enough to cause considerable local pain and has been reported to sometimes cause tissue death (necrosis) at and near the bite. There is no dimorphism in color or markings. Their coloration is rather subdued, being a mixture of brown and rust earth shades. They have a herringbone pattern on the top side of their abdomens. The hobo spider has solid light-brown-colored legs. It prefers moderately dry and warm environments. It is most commonly found in gardens, fields, hedges, and the like. Back to Top


Honey bees
All honey bees live in colonies where the workers will sting intruders as a form of defense, and release pheromones that accentuate the attack response. The different species of honey bees are distinguished from all other bee species by the possession of small barbs on the sting, but these barbs are found only in the workers. The sting and associated venom sac are also modified so as to pull free of the body once lodged (autotomy), and the sting apparatus has its own musculature and ganglion which allow it to keep delivering venom once detached. Back to Top

Horse flies
These flies are often considered pests because of the painful bites that many, though not all, of the species can inflict on animals and humans. Females usually also feed on blood which aids in egg development. Males lack the necessary mouth parts (mandibles) for blood feeding. Most horse flies feed on mammal blood, but some species are known to feed on birds, amphibians or reptiles. Horse flies are most active in hot weather, mostly in summer and autumn during the daylight hours. Most species also prefer a wet climate, which makes it easier for them to breed. Horse flies are known to mate in horse feces. Back to Top

Housefly
The House Fly is the most common fly occurring in homes, the most familiar of all flies and indeed one of the most widely distributed animals; it is a pest that can facilitate serious diseases. Houseflies can take in only liquid foods. They spit out saliva on solid foods to pre-digest it, and then suck it back in. They also vomit partially digested matter and eat it again. Back to Top


House mouse
It is a small mammal and a rodent. House mice almost always live in close proximity of humans. House mice usually walk, run or stand on all fours, but when eating, fighting or orienting themselves, they stand only on the hind legs, supported by the tail. When running, the horizontal tail serves for balance; the end stands up vertically, unless the mouse is frightened. Mice are good jumpers, climbers and swimmers. Mice are mostly active during dusk or night; they do not like bright lights. They live in a wide variety of hidden places that are near food sources and construct nests from various soft materials. Mice are territorial and one dominant male usually lives together with several females and young. House mice usually live in close proximity of humans, in or around houses or fields. House mice can transmit diseases, and their droppings can spoil foods. They can also cause substantial damage when feeding on grain. Back to Top

Mosquito
Mosquitoes are principally nectar feeders with only the females requiring a meal of blood. Mosquito bites often swell up hours after happening, causing a red ringed white bump about a centimeter in diameter. This bump can itch for days and over-scratching the bite can cause it to bleed. Continued over-scratching can cause scars. Mosquito bites can transmit diseases, such as malaria and West Nile Virus, so authorities in many areas take measures to reduce mosquito populations through pesticides or more organic means. An easy way to reduce mosquito populations in a residential area is the removal of standing water (where mosquitoes breed), and the use of repellents, such as DEET. Back to Top

Mud dauber wasp
They are solitary insects that build small nests out of mud in or around homes, barns, and other structures. Although generally non-aggressive, they can be provoked into defending their nests. Back to Top

Oriental cockroach
The oriental cockroach tends to travel somewhat more slowly than other species. They are often called waterbugs since they prefer dark, moist places. They can often be found around decaying organic matter, and in sewers, drains, damp basements, porches, and other damp locations. They can be found outside in bushes, under leaf groundcover, under mulch, and around other damp places outdoors. Back to Top

Pavement ant
A pavement ant is a common household pest. Their name comes from the fact that they usually make their homes in pavement. These ants will eat almost anything, including insects, seeds, honeydew, honey, bread, meats, nuts and cheese. These ants do not pose a public health risk, but they can contaminate food and should be avoided. Back to Top

Pharaoh ant
The pharaoh ant (Monomorium pharaonis) is a small (2 mm) yellow, almost transparent ant known for being a major indoor nuisance pest, especially in hospitals. Unlike most ants the Pharaoh ant is polygynous, meaning its colonies contain many queens (from 2 to over 200). An individual colony normally contains 1000 - 2500 workers but a high density of nests gives the impression of massive colonies. Back to Top

Roof Rat
By most standards, rats are considered pests or vermin. They can be very destructive to crops and property. Rats can quickly overpopulate when they live in a place where they have no predators, such as in certain cities, and their numbers can become hard to contain. Rats can carry over thirty different diseases dangerous to humans, including Weil's disease, typhus, salmonella and bubonic plague. Because rats are nocturnal, daytime sightings of rat activity can mean that their nesting areas have been disturbed or, more likely, that there is overpopulation of them in the local area. Back to Top

Tarantulas
Tarantulas are long-legged, long-living spiders, whose entire body is covered with short glittery hairs. Despite their often scary appearance and reputation, none of the true tarantulas are included in the list of deadly spiders (spiders having a strong toxin, dangerous to humans). Their natural habitats include savanna, grasslands such as the pampas, rainforests, deserts, scrubland, mountains and cloud forests. Tarantulas are nocturnal predators, killing their prey by injecting venom through their fangs. The hungry tarantula typically waits partially hidden at the entrance to its retreat to ambush passing prey. It has sensitive hairs that enable it to detect the size and location of potential victims from the vibrations caused by their movements. Some species also use their silk fiber to detect motion (when prey triggers a line). Like many other spiders, it cannot see much more than light, darkness, and movement (see spiders for more about their eyesight), and uses its sense of touch to perceive the world around it. Some tarantulas succeed in occasionally capturing small birds, small mammals such as mice, and even small fish, but their ordinary prey consists of insects such as crickets (for ground dwellers) and moths (for arboreal species). Burrowing tarantulas live underground, in burrows. Other tarantulas make their homes under rocks or tree trunks or under the loose bark of trees. Still others build silken nests on trees, cliff faces, and the walls of buildings or in plants. Tarantulas are well suited for climbing. Back to Top

Termites
Termites feed on dead plant material, generally in the form of wood, leaf litter or soil, and about 10% of the 4,000 odd species (about 2,600 taxonomically known) are economically important as pests that can cause serious structural damage to buildings, crops or plantation forests. Termites only superficially resemble ants; their "white ant" name arises from their similar size and social habits. Compared with ants, they are softer, whiter, shorter-legged, fatter and generally much slower moving. Because of their wood-eating habits, termites sometimes do great damage to buildings and other wooden structures. Their habit of remaining concealed often results in their presence being undetected until the timbers are severely damaged and exhibit surface changes. Once termites have entered a building they do not limit themselves just to wood, also damaging paper, cloth, carpets, and other cellulosic materials. Often, other soft materials are damaged and may be used for construction. Particles taken from soft plastics, plaster, rubber and sealants such as silicon rubber and acrylics are often employed in gallery construction Termites try to avoid exposure to unfavorable environmental conditions. They tend to remain hidden in tunnels in earth and wood. Where they need to cross an impervious or unfavorable substrate, they cover their tracks with tubing made of feces, plant matter and soil. Sometimes these shelter tubes will extend for many meters, such as up the outside of a tree reaching from the soil to dead branches. Most termite barrier systems used for buildings aim to prevent concealed termite access, thus forcing them out into the open where they must form clearly visible shelter tubes to gain entry. Back to Top

Tick
Ticks are ectoparasites (external parasites), living by hematophagy on the blood of mammals, birds, and occasionally reptiles and amphibians. Ticks are important vectors of a number of diseases. Soft ticks typically live in crevices and emerge briefly to feed, while hard ticks will attach themselves to the skin of a host for long periods of time. Tick bites look like mosquito bites, but can also sometimes bruise or resemble a bulls eye. Ticks are blood-sucking parasites that are often found in tall grass, where they will rest themselves at the tip of a blade so as to attach themselves to a passing animal or human. It is a common misconception that the tick can jump from the plant onto the host. Physical contact is the only method of transportation for ticks. They will generally drop off of the animal when full, but this may take several days. Ticks have a harpoon-like structure in their mouth area, known as a hypostome, that allows them to anchor themselves firmly in place while sucking blood. Back to Top

Twig Borer
The reason the bug kills trees is because they eat so much bark that the tree cannot get any nutrients up to the top of it. Since the inner core (heartwood) of trees is dead and the inner bark (sapwood) is the living portion of the tree, the bug effectively strangles the tree. A tell-tale signs of infestation are new shoots sprouting from the bottom of the tree. As long as the bugs didn't eat all the bark right at the very base of the tree, the small shoots at the bottom still get nutrients. Surprisingly, even after the tree is cut down, some of these shoots keep on growing. Another sign of infestation is small holes in the bark where the bugs have bored their way out. Back to Top

Yellow jackets
They live in colonies and build globular paper nests. They can and will sting repeatedly, especially when trapped in clothing, because their stingers don't have barbs. They will sting without apparent provocation, and so can be major pests. They will sting in order to defend their nest. In autumn, they switch from collecting arthropods and nectar to scavenging other food sources, which can increase their contact with people. Back to Top