Wondering what type of insect or rodent has invaded your household or yard?
The following are some of the pests commonly found in the Montreal area. Whether they be rodents (mice, rats, etc) or insects (ants, bedbugs, spiders, cockroaches, etc), Learn how to identify specific species, check for signs of infestation, insect and rodent habits and your options for controlling the outbreak or invasion.
(Source: PCT Technician’s Handbook)
Description
Carpenter ants are among the largest ants found in North America, ranging from 1/8 to ½ inch long; the queens are slightly larger. The worker ants of an established colony vary in size. Commonly, these ants are black; however, some ant species are red and black, solid red, or brown. These ants have one node in the petiole and a circle of tiny hairs on the tip of the abdomen. When seen from the side, the ant’s thorax is evenly rounded.
Habits
Carpenter ants are social insects which usually nest within wood. These ants commonly excavate galleries or tunnels within rotting and sound trees and in structures readily infest wood, foam insulation, and cavities. Carpenter ants prefer to excavate wood damaged by fungus and often are found in conjunction with moisture problems. These ants enter structures through gaps and cracks while foraging for food. However, the appearance of large numbers of winged adults within a structure indicates that the ant nest(s) exists indoors. The worker ants push wood shavings and pieces of foam insulation out of the nest through slit-like openings in the surface of the wood or other nesting-site material. This material, which may contain fragments of other insects, and structural moisture problems are clues to look for when trying to locate a colony of ants within an infested structure. Rustling sounds in wall voids are another indication that there is a nearby colony of ants.
Description
The thorax of the black ant lacks spines and the petiole of the ant has two nodes. The ant’s abdomen is tipped by a small stinger. Each antenna ends in a three-segmented club. Little black ant workers are 1/16 inch long. These same characteristics also describe the Pharaoh ant; however, the characteristic which distinguishes these two species of ants is the jet black color of the little black ant.
Description
The thorax of the black ant lacks spines and the petiole has two nodes. The ant’s abdomen is tipped by a small stinger. Each antenna ends in a three-segmented club. Little black ant workers are 1/16 inch long. These same characteristics also describe the Pharaoh ant; however, the characteristic which distinguishes these two species is the jet black color of the little black ant.
Habits
Little black ants are found throughout North America, nesting beneath stones, in lawns, and in areas that lack vegetation.
Ant nests are easily located as they form small craters of fine soil at their entrances. These ants also nest within rotting wood and behind the woodwork or masonry of structures. Indoors, ants can be found under the edge of carpeting and within old termite galleries and wall voids.
Little black ants prefer to feed on a variety of foods including honeydew produced by aphids, meats, and greases. These ants are predaceous on other insects. Indoors, they feed on greases and sweet foods.
Description
Pavement ants are 1/16 to 1/8 of an inch long with a dark body and lighter colored legs. These ants have two small spines on the back portion of the thorax, tow nodes in their petioles, and their bodies are covered with still hairs. Pavement ants are easily identified by the narrow, parallel grooves on their heads and thoraxes.
Habits
Pavement ants commonly are found in metropolitan areas in eastern and central Canada. These ants nest outdoors beneath flat stones, sidewalks, and concrete slabs as well as along curbing. Pavement ants invade structures in search of food and are particularly problematic in areas where slab-on-grade construction is prevalent. Inside structures, the ants nest within walls, insulation, floors, and, during the winter, near heat sources.
Although pavement ants feed on insects, meats, seeds, and sweets, these ants prefer meats and greases. Pavement ants are slow moving and are frequently observed in areas where they are prevalent. They forage in trails as far as 30 feet from the nest. Although Pavement ants are not particularly aggressive, worker ants do bite and sting.
Description
Pharaoh ants are very small with worker ants about 1/16 inches long. Coloration ranges from yellow to light brown. The thorax of the ant lacks spines and the petiole has two nodes. These ants can be distinguished from thief ants by the three-segmented club at the end of their antenna.
Biology
These ants do not swarm; female ants mated within the nest and new colonies are formed by ‘budding’ which means that part of the main ant colony moves en masse to a new location. There may be hundreds of thousands of ants within a single ant colony. Worker ants live approximately nine to 10 weeks and queens four to 12 months.
Habits
Pharaoh ants can nest outdoors and are, at times, a crop pest. These ants are a major problem in homes and institutions such as hospitals, hotels, or prisons and in apartment complexes. Pharoah ants nest within warm, hard-to-reach locations in walls, subfloor areas, wall sockets, attics, cracks and crevices, and behind baseboards and furniture.
Description
Adult centipedes are yellowish to dark brown, often with dark markings, and are 18 to 6 inches long. The body is flattened with 15 to 177 body segments which typically have one pair of legs each. They also have one pair of slender antennae. The house centipede is grey-yellow with three stripes down its back and very long legs banded with white. The largest centipedes are found in the Southwest.
Biology
Typically, centipedes overwinter outdoors and in the summer, lay 35 eggs or more in or on the soil. Newly-hatched centipedes have four pairs of legs; during subsequent molts, the centipede progressively increases the number of legs until becoming an adult. Adults of many species live one year, but some live as long as six years.
Habits
Centipedes, including the house centipede, prefer to live in moist environments. The house centipede can live indoors in damp basements, moist closets, and bathrooms, and outdoors under stones, decaying firewood, objects on the ground, piles of leaves, and mulch. Most centipedes are active at night.
A centipede’s front pair of legs has poison glands which are used to kill prey, such as insects and spiders. Most of their water is obtained from their prey. Although centipedes can bite humans, the bite is seldom worse than a bee sting.
Description
Most millipedes are brown or black, but some species are orange or red. They range from 5 to 4 inches in length. There are many species of millipedes most of which are long, cylindrical, multiple-segmented, worm-like creatures; however, a few appear to be flattened. Every millipede has two pairs of legs attached to each apparent body segment.
Biology
Females lay 20 to 300 eggs in nests in the soil which hatch after several weeks. Initially, the young have only three pairs of legs and seven segments. Over time, they undergo a series of seven to 10 molts during which the number of legs and segments increase. Many species reach sexual maturity within two years, but some require four or five years to complete development. Adults can live several years. Most species overwinter as adults or young.
Habits
Millipedes thrive outdoors in settings where there is moisture and decaying organic matter such as under trash, grass clippings, mulch, rotting firewood, leaf litter, or unclean drains. Thus, they can build up tremendous populations in forest litter and compost heaps. Millipedes become structural pests when they invade homes and other structures, sometimes in staggering numbers. This occurs when standing water in their natural habitat forces them out. Indoor movement also is caused by drought and their natural migratory and mating instincts in the fall. Millipedes usually die within a few days of entering a structure unless there is a source of high moisture and a food supply
Millipedes are active at night. They are scavengers which feed on decaying organic matter. Most species produce a foul-smelling fluid emitted from the sides of their bodies which is toxic to some insects and small animals and can cause blisters on human skin.
Description
American cockroaches are 1 3/8 to 2 1/8 inches long when mature, red-brown, and characterized by fully developed wings which completely cover the abdomen. The pronotum, the shield-like area behind the head, has a dirty-yellow band around its edge.
The nymphs are gray-brown and ¼ inch long when they emerge from the egg capsule. As they develop, they become more red-brown, and the yellow band becomes more prominent on the pronotum. The purse-shaped egg capsule is dark red-brown in color, 3/8 inch long, and typically has eight eggs per side.
Biology
During her lifetime, the female American cockroach produces nine to 10 egg capsules each of which contains from 14 to 16 eggs. The capsules are3 dropped or, using secretions from her mouth, glued in protected locations such as cracks and crevices near food sources. The nymphs molt 10 to 13 times over 168 to 786 days before becoming adults. Adult females live an average of 440 days; males about 200 days. Large populations of American cockroaches accumulate in secluded locations because they have such a long life span.
Habits
American cockroaches are not common pests in most homes. They can be abundant in sewers and commercial facilities such as grocery stores, prisons, restaurants, hospitals, and in office and apartment buildings. They prefer to inhabit warm damp locations including steam tunnels, boiler rooms, and sewage ejector pits. Strong fliers, they easily migrate from building to building. In the summer, large numbers accumulate in outdoor locations such as dumps, alleys, and yards, and in the fall, they migrate into surrounding structures. Although they feed on a variety of materials, they prefer fermenting foods.
Description
German cockroaches are ½ to 5/8 inch long when mature, light brown to tan, and have fully developed wings. The pronotum or the shield-like segment behind the head has two dark parallel bars on it. The adult males are somewhat narrower than the females when viewed from below. The nymphs, 1/8 inch long when they emerge from the egg capsule, are almost uniformly dark except for a light tan area on the back of the second and third segments. As they develop, the light tan area becomes larger until, as mature nymphs, they have two parallel black bars separated by a light tan area. The purse-shaped egg capsule of the German cockroach is light brown, ¼ to 3/8 inches long, and, typically, has 15 to 20 eggs per side.
Habits
German cockroaches are the most common household insect in North America. This pest typically infests kitchens and bathrooms but will live inside heated structures in which there is food, water, and harborage. Rarely are they found outdoors and then only during warm weather. German cockroaches gain entry into structures in grocery bags, cardboard boxes, and drink cartons; infested equipment such as used refrigerators, toasters, and microwaves, etc.
German cockroaches are active at night, leaving their harborage to find food and water. Otherwise, they remain hidden in dark, secluded harborage areas, including under cupboards, behind cabinets, in wall voids, and around motor housings in appliances, where they spend 75 percent of their time. At most, only one-third of a population will forage at night. Observation of foraging cockroaches during the day is a good indication that there is a tremendous population. Cockroaches congregate in harborage sites but as the population increases, overcrowding forces some of them to relocate.
Description
The adult bed bug is 3/16 inch long and ovate; coloration is rusty-red or mahogany. The bed bug is flat and thin when unfed but becomes more elongate, plump, and red when it is engorged with blood. Four-segmented antennae are attached to the head between the prominent compound eyes. The three-segmented beak, or proboscis, is located beneath the head and passes back between the front legs. The bed bug cannot fly as its wings are reduced to short wing pads.
Habits
The bed bug hides in cracks and crevices during the day, preferring to rest on wood and paper surfaces instead of stone and plaster. It leaves these harborage areas at night to feed on its host which may include humans, birds, hogs, and family pets. The blood meal requires three to 10 minutes and usually goes unnoticed by the victim. After feeding, the bite site may become inflamed and, in sensitive individuals, itch severely. Although the bed bug has been associated with more than 25 diseases, transmission has not been conclusively proven. Over time, the harborage areas become filled with the molted skins, feces, and old eggshells of the resident bed bugs. These areas have a characteristic ‘stink bug’ smell caused by a secretion emitted by the bed bug.
Description
Adult earwigs are ¼ to 1 inch long and dark brown to black with a red head and pale yellow-brown legs. The body is long and flattened. Earwigs usually have two pairs of wings, the hind wings are fully developed and folded beneath the short, leathery front wings. The thread-like antennae are half as long as the body. The most notable characteristic is the forceps, the pincer-like appendages at the end of the abdomen.
Habits
Interestingly, earwig females display a mothering instinct, protecting the nest and the nymphs until they have reached their second molt. Earwigs usually live outdoors feeding on plant material. Very general feeders, they seldom do much damage to plants. They are active at night, hiding during the day under stones and other objects.
Typically outdoor insects, earwigs become household pests when they invade structures, usually in the fall or at night. Indoors, they usually are found in cracks and crevices and under furniture and carpeting. They are considered pests because of their presence and because of the foul odor emitted when crushed. Some species are attracted to lights.
Description
Silverfish are primitive, even older than cockroaches. They are wingless insects that are 1/2 inch long when fully grown. Somewhat flattened and carrot-shaped, they are covered with silvery scales. Three long, slender, antennae-like appendages project from the end of the abdomen, giving them the name “bristle tails.”
Biology
The female lays one to three eggs per day in crevices or under objects. She molts after laying a batch of eggs and sheds her skin as many as 50 times after becoming an adult. The eggs hatch in about 43 days at 72° to 90°F and at least 50 to 75 percent relative humidity. The young silverfish look exactly like the adults, except that they are smaller, and feed on the same foods. Under ideal conditions, they molt every two to three weeks becoming adults in three to four months. However, under poor conditions, this might require two to three years. These insects are very long lived, commonly living at least three years. The silverfish are unlike most other insects in that they continue to molt after they become adults.
Habits
Silverfish are tropical insects that easily adapt to the structural environment. They live in warm (71° to 90°F), moist locations in structures, hide during the day, and rest in tight cracks and crevices. They roam great distances looking for food, but once a food source is located, they remain close until the supply is exhausted. They can be found throughout a structure from the basement to attics. Outdoors, they can be found in mulch and beneath siding and roof shingles, particularly cedar shakes. Silverfish readily feed on books, cloth, and sometimes dried meats and dead insects. They seem to be especially fond of the sizing on books and paper and the glues and pastes found on wallpaper, labels, and paper products.
Description
Pillbugs and sowbugs are dark gray, 1/4 to 5/8 inch long, oval crustaceans that are humpbacked, appear to be covered with segmented armor, and have seven pairs of similar legs. Pillbugs can be distinguished from sowbugs because pillbugs are able to roll up into a ball when alarmed and lack the two prominent tail-like appendages that characterize sowbugs.
Biology
Female pillbugs and sowbugs carry their eggs in a “brood pouch,” or marsupium, where the young hatch in about 45 days. There are 24 to 28 eggs in each brood and one to three broods produced each year. The young molt every one to two weeks until they become adults which live for about two years.
Habits
Pillbugs and sowbugs usually are found in moist settings where they feed on organic matter. Outdoors, they commonly are found beneath stones, boards, and piles of plant material. Pillbugs and sowbugs invade basements, crawlspaces, and sometimes other parts of structures where moisture is higher than normal. They cause no damage but are considered to be a nuisance. Unless disturbed, they usually are active only at night.
Description
Adult Indian meal moths have a 4 to inch wing spread. The wings are a burnished copper, almost purple, with a broad gray band near where they attach to the body. The mature larvae are dirty white, pink, brown, or light green, and about 1/2 inch long. The head and top of the first body segment behind the head are reddish to yellowish brown.
Biology
Adult females lay 100 to 400 eggs at night on the larval food over a one- to 18-day period. Larval development requires 13 to 288 days. The average life cycle, egg to egg, requires 25 to 135 days. Usually there are four to six generations per year depending on the food supply and temperature. Indian meal moths usually overwinter as larvae. The adults are more active at dusk and are attracted to light.
Habits
Indian meal moths are one of the most common stored product pests found in homes, food processing plants, grain storage and processing facilities. The larvae prefer to feed on coarsely ground flour and meal but also commonly feed on whole grains, dried fruit, nuts, chocolate, beans, crackers, biscuits, dry dog food, bird seed, and red peppers.
The larvae produce a silk webbing over the surface of the materials upon which they feed which contains large amounts of their frass (feces). The damage caused by this insect’s feeding is compounded by the presence of this repulsive webbed mat. The larvae move into cracks and crevices in the food material, feeding within or near this silken mat. Mature larvae generally move away from infested materials to pupate in cracks or crevices. This behavior pattern is often what allows them to be discovered by homeowners.
Description
Social wasps have the typical “wasp” body type that features a very distinct head with chewing mouthparts, short elbowed antennae, and large compound eyes. The thorax and abdomen are brightly marked with yellow, red, or brown on a black background. The wasps have four clear or smoky-brown wings and a short, narrow attachment between the thorax and the abdomen. The abdomen is spindle-shaped and tipped with a long stinger.
Yellow jackets usually are marked with bright yellow and black pattern. They appear to be hairless and are about 3/8 to 5/8 inch long. The bald-faced hornet is similar in appearance except that it is black and white and 5/8 to 3/4 inch long.
The giant European hornet is brown and yellow and 3/4 to 13/8 inch long. Paper wasps can be distinguished from yellow jackets and hornets because their abdomen is tapered at the tip and at the point where it joins the thorax. They are sometimes marked with yellow, brown, or red patterns on black and are 5/8 to 3/4 inch long.
Biology
Social wasps have large nests which contain three types of individuals, or castes: queens, workers, and males. The males and queens are produced in the colony in late summer. They mate, and the fertilized queen overwinters in a protected site. In the spring, she seeks an appropriate nesting site in which she builds a paper nest using chewed-up wood fibers. Eggs are laid within the cells of the nest, and the young larvae are fed bits of chewed meat or insect parts by the queen and later by the workers.
Habits
Yellow jackets and hornets build their flat paper nests ir stacks which are surrounded by a paper envelope. Yellow jackets usually build their nests below ground and in other protected locations. Bald-faced hornets prefer to build their nests in trees and on the sides of buildings. European hornets build their nests inside hollow trees, wall voids, and underground. Paper wasps build open flat nests without a paper envelope which usually are found under the eaves of a house and in other protected locations. Social wasps use their nests for only one season.
Unlike bees, these wasps aggressively defend their nests and can inflict multiple stings. They produce very large colonies, some containing as many as 30,000 individuals. These insects are considered to be beneficial because they feed their young a wide variety of insects. They become a nuisance, however, when they build nests in or near structures, scavenge for food in recreational areas and in other places frequented by humans, and seek overwintering sites within structures.
Identification
The house mouse is the most common and economically important commensal (living in close association with humans) rodent. The house mouse is gray and weighs 12 to one ounce. Its body is three to four inches long and the tail three to four inches long. The mouse’s muzzle is pointed, the ears are large, the eyes and body are small. Typically, house mice are slightly smaller than deer mice. Adult mouse droppings are 78 to 14 inch long and rod-shaped with pointed ends.
Biology
The female house mouse reaches sexual maturity in 35 days and averages eight litters of mice per year, each of which averages six young. Thus, with 30 to 35 weaned mice per year, populations build up rapidly. The mice typically produce their largest litters in the spring, depending on climatic conditions, and begin to breed at five to six weeks of age. The life span of a mouse is one year.
Habits
House mice are found throughout Canada and the United States. House mice are good climbers, can jump 12 inches high, and eight feet down. House mice easily squeeze through holes and gaps wider than 1/4 inch. These mice are very social in their behavior, very inquisitive about things in their environment, and readily explore anything new.
House mice prefer to nest in dark secluded areas where there is little chance of disturbance, and in areas where nesting materials, such as paper, cardboard, attic insulation, cotton, etc., are readily available. Their foraging territories are small, usually no more than 20 feet; however, if abundant food is nearby they nest within four to five feet. These mice nibble on food, preferring items such as seeds and cereals. House mice feed at dusk and just before dawn. The major health risks associated with house mice are Salmonella contamination and leptospirosis.
Description
The roof rat is a commensal (living in close association with humans) rodent. The roof rat’s head and body are six to eight inches long and the tail is an additional seven to 10 inches. This species of rat has a slight body which weighs five to nine ounces. The roof rat’s fur is soft, smooth, and brown in color with some black hairs. The rat’s muzzle is pointed, eyes and ears are large, and the scaly tail, which is uniformly dark, is longer than the head and body combined. Roof rat droppings are up to inch long and spindle shaped with pointed ends.
Biology
Roof rat adults are sexually mature in two to five months. Female roof rats produce four to six litters per year, each averaging six to eight young mice. Adult roof rats live from nine to 12 months. These rats have poor sight, but keen senses of smell, taste, hearing, and touch.
Habits
Roof rats are nocturnal. These rats are shy about new objects and very cautious when things change in their environment and along their established runs. Outdoors, roof rats prefer to nest in trees and, occasionally, in burrows and vegetation. The rats easily enter buildings through 12-inch and larger gaps. In buildings, rats prefer to nest in the upper levels of the building, and, occasionally, in basements and sewers. They prefer foods such as fruits, vegetables, and cereals. Roof rat’s foraging range is 100 to 150 feet from their nest.
Roof rats are associated with various diseases and occasionally bite. Plague is of little concern because it has not occurred in rats in Canada or the United States for many years. However, leptospirosis is vectored by rats, and thus is a disease of great concern. This disease is acquired by eating food and drinking water which are contaminated with infected rat urine. Rats also cause significant structural damage and product destruction.
Description
The Norway rat is the largest of the commensal (living in close association with humans) rodents. The Norway rat’s head and body are 7 to 10 inches long and the tail is an additional 6 to 8 inches. The Norway rat has a stocky body and weights 7 to 18 ounces. The rat’s fur is coarse, shaggy, and brown with some black hairs. The rat’s muzzle is blunt, eyes and ears are small, and the tail, which is bi-colored, is shorter than the head and body combined. Norway rat droppings are up to ¾ inch long with blunt ends.
Biology: Norway rat adults are sexually mature in two to five months. Female Norway rats produce three to six litters per year, each averaging seven to eight young. Adult rats live from six to 12 months. They have poor sight, but keen senses of smell, taste, hearing, and touch.
Habits
Norway rats are nocturnal. They are shy about new objects and very cautious when things change in their environment and along their established runs. Outdoors, Norway rats prefer to nest in burrows in the soil under sidewalks and concrete ads, stream/river banks, railroad track beds, next to buildings, and in low ground cover. The rat burrows typically have one main entry hole and at least one escape hole. The rats easily enter buildings through ½ inch and larger gaps. In buildings, these rats prefer to nest in the lower levels including crawlspaces, basements, loading docks, and sewers. Rats prefer foods such as meat, fish, and cereals, and require a separate non-food water source. Norway rat’s foraging range is 100 to 150 feet from their nest.
Norway rats are associated with various diseases and occasionally bite. Plaque is of little concern because it has not occurred in rats in North America for many years. However, leptospirosis is vectored by rats, and thus is of great concern. This disease is acquired by eating food and drinking water which are contaminated with infected rat urine. Rats also cause significant structural damage and product destruction.