The American cockroach (Periplaneta americana), also known as the Palmetto Bug or Waterbug, particularly in the southern United States, is the largest species of common cockroach, and often considered a pest. It is native to the Southern United States, and common in tropical climates. Human activity has extended the insect's range of habitation. Specimens have been observed in eastern North American cities as far north as New York City, Toronto, and Montreal, though its intolerance to cold restricts it to human habitations. Global shipping has transplanted the insects to world ports including Tenerife (Spain), Southern Spain, Greece, Taiwan, and Cape Town and Durban, South Africa.
The insect is believed to have originated in Africa, but had become established in the southern U.S. by the time that it was given its name
American cockroach adults grow to an average length of around 4 centimetres (1.6 in) and about 7 millimetres (0.28 in) tall. They are reddish brown and have a yellowish margin on the body region behind the head. Immature cockroaches resemble adults except that they are wingless.
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 considered one of the fastest running insects.
In an experiment carried out at the University of California at Berkeley (USA) in 1991, a Periplaneta americana registered a record speed of 5.4 kilometres per hour (3.4 mph), about 50 body lengths per second, which would be comparable to a human running at 330 km/h (205 mph).
It has a pair of large eyes each having over 2000 individual lenses thus making it a very active night animal that shuns light.
American cockroaches generally live in moist areas, but can survive in dry areas if they have access to water. They prefer warm temperatures around 29 °C (84 °F) and do not tolerate cold temperatures. In residential areas, these cockroaches live in basements and sewers, and may move outdoors into yards during warm weather. These cockroaches are common in basements, crawl spaces, cracks and crevices of porches, foundations, and walkways adjacent to buildings. They have been known to fly during mating season.]
The American cockroach is a scavenger that feeds on decaying organic matter and a variety of other foods. It is particularly fond of fermenting foods.
Females produce egg cases and carry them protruding from the tip of the abdomen for about two days. Egg cases are then generally placed on a surface in a hidden location. Egg cases are about 0.9 centimetres (0.35 in) long, brown, and purse shaped. Immature cockroaches emerge from egg cases in 6 to 8 weeks and require 6 to 12 months to mature. Adult cockroaches can live up to one year, during which females produce an average of 150 young.
Due to their large size and slow development, large infestations of these insects are not common within houses. However, during certain times of the year, these cockroaches may move inside a house from outside. In cold weather these cockroaches may move indoors, seeking warmer temperatures and food. Cockroaches may enter houses via sewer connections, under doors, around plumbing, air ducts, or other openings in the foundation. Cockroach populations may be controlled through the use of insecticides.
The German cockroach, Croton bug or Steam fly (Blattella germanica) is a small species of cockroach, measuring about 1.3 cm (0.51 in) to 1.6 cm (0.63 in) long. It can be tan through brown to almost black, and has two dark parallel streaks running from the head to the base of the wings. Although it has wings, it is unable to sustain flight. The German cockroach is one of the most common and prominent household cockroaches in the world, and can be found throughout many human settlements. These insects are particularly fond of inhabiting restaurants, food processing facilities, hotels, and nursing homes. In colder climates, they are found only near human habitats, since they are not very tolerant to cold. However German cockroaches have been found as far north as Alert, Nunavut. The German cockroach is originally from Asia, it is very closely related to the Asian cockroach, and to the casual observer they appear nearly identical and may be mistaken for the other. This cockroach can be seen in the day occasionally, especially if there is a large population or if they have been disturbed. However, sightings are most commonly reported in the evening hours as they are most active at night.
The German cockroach is very successful at establishing an ecological niche in buildings, and is very hardy and resilient against attempts at pest control. This is because of the large number of nymphs produced from each egg case, the short period between birth and sexual maturity, and their ability to easily hide due to their small size. The mother also carries the egg case (called an ootheca) with her during the germination period, rather than depositing it like other species, a practice which would leave them vulnerable in a human habitat to zealous attempts to wipe them out. This cockroach is also smaller than many other species so it can more easily hide and fit into very small cracks and crevices to evade humans. That is also the main reason they can most effectively be controlled with bait in cracks and crevices near harborages. These type of pest control methods should kill 95% of the overall population in a property due to their fast reproductive cycles.The German cockroach, discounting the presence of pets, has few natural predators inside a human habitat. The German cockroach's thigmotactic nature compounds the difficulty of pest control treatment. The immature cockroaches will live off excretions and moults from the adult cockroaches and thus can remain hidden away from most surface treatments.
The German cockroach is omnivorous and a scavenger. They particularly like starch, sugary foods, grease and meats. In certain situations where there is a shortage of foodstuffs, they may eat household items such as soap, glue and toothpaste or they may even turn cannibalistic, often chewing on the wings and legs of each other.
The oriental cockroach (also known as: waterbug and Blatta orientalis) is a large species of cockroach, measuring about 1 in (2.5 cm) in length at maturity. It is dark brown to black in colour and has a glossy body. The female Oriental cockroach has a somewhat different appearance to the male, appearing to be wingless at casual glance but has two very short and useless wings just below its head. It has a wider body than the male. The male has long wings, which cover a majority of its body and are brown in colour, and has a more narrow body. The odd male is capable of very short flights, ranging about 2 to 3 meters. The female oriental cockroach looks somewhat similar to the Florida woods cockroach, and may be mistaken for it.
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.
In order to thrive, cockroaches need a place to hide. They prefer warm places and a relatively high humidity if possible; they also need a source of food/liquid. The optimum temperature for oriental cockroaches is between 20 °C (68 °F) to 29 °C (84 °F). Female oriental cockroaches have vestigial tegmina (reduced forewings) and males have longer tegmina. Cockroaches are mainly nocturnal. Oriental cockroaches can be elusive in that a casual inspection of an infested dwelling during the day may show no signs of roach activity.
Signs of cockroaches are their oothecae, which are “egg cases” containing up to 16 individual eggs in the case of oriental cockroaches. These oothecae are dropped by females and hatch on their own in about two months. Oriental cockroaches can be harder to get rid of than other roaches. Although adults can be fairly easily killed by the application of residual insecticide, the insecticides can get washed away, and two months later females can hatch new nymphs.