There is hardly any other pest that is more universally despised than the cockroach. The reasons why they are hated so much, are:
- Cockroaches are potential spreading agent for many disease organisms, including Salmonella, E. Coli, Hepatitis E, diarrhea, and dysentery; and they may play a role in the transmission of pneumonia and SARS (Severe acute respiratory syndrome).
- Cockroaches and their shed skins and by-products can cause increased rates of asthma and allergies among children and older people and people with allergies in general.
- Cockroaches emit a nauseating odor and contaminate our food with their droppings and filth.
- Their sneaky behaviour, high reproductive rates, and impressive ability to develop resistance to pesticides make cockroaches among the most challenging household pests to control.
What are Cockroaches?
Cockroaches have long antennae, long legs adapted to running, and a flat extension of the upper body wall that conceals the downward pointing head. They range from 1/4 in. to 3 in. (.6-7.6 cm) in length.
These insects are usually flat and have an oval outline. In many other respects they are similar in morphology to grasshoppers, crickets, katydids, stick insects, and mantids, their closest relatives. Their presence in significant numbers does result in a foul odour.
Cockroaches may be winged or wingless, but even winged species do not always fly. Adults range from 1 mm (0.04 in) to more than 9 cm (3.6 in) in length. They are sensitive to light and being largely nocturnal they prefer darkness. Their long and highly sensitive antennae and sensory bristles enable them to detect tiny amounts of food and moisture in the environment. The cerci, sensory structures extending from the rear of the abdomen, can sense even the minute air movements, enabling the cockroach to rapidly detect and flee from a potential danger. Most cockroaches can run fast and are difficult to catch due to their soft, slippery outer skin, called the cuticle. They can hide in very narrow crevices. The oily cuticle also protects them from dehydration.
About 4000 species are known worldwide; most inhabit the warm tropical regions of the globe. About 25 species have attained worldwide distribution due to accidental transport in commerce and their affinity for human habitation. Among these are most of the important pest species. Cockroaches are an ancient group, having changed little in appearance in 320 million years. Fossil records indicate that they were the predominant insects during the Carboniferous period 345 to 280 million years ago.
Only American Cockroach is native North America, all other species came along with cargo.
What are the common Cockroach species in Ontario?
Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitats. About four species are well known as pests
Among the best-known pest species are the American Cockroach, Periplaneta americana, which is about 30 mm (1.2 in) long; the German Cockroach, Blattella germanica, about 15 mm (0.59 in) long; the Brown Banded Cockroach, Supella longipalpa, about 14mm or (0.625 in) long, and the Oriental Cockroach, Blatta orientalis, about 25 mm (0.98 in). Tropical cockroaches are often much bigger,
How can I get rid of Cockroaches?
The first step in addressing any cockroach problem is sanitation. This means doing a thorough clean up of sources of food, water, and harborage. Sealing any cracks and gaps in washroom and kitchen cabinetry. Be especially careful about paper products used for lining, unnecessary and untidy storage of cardboard boxes, and other refuse that can provide roaches with a protected place to feed and live.
Our method of exterminating these pests is dployment of Commercial bait.
Cockroaches are most common in tropical and subtropical climates. Some species are in close association with human dwellings and widely found around garbage or in the kitchen. Cockroaches are generally omnivorous with the exception of the wood-eating genus Cryptocercus; these roaches are incapable of digesting cellulose themselves, but have symbiotic relationships with various protozoans and bacteria that digest the cellulose, allowing them to extract the nutrients. The similarity of these symbionts to those in termites are such that the genus Cryptocercus has been believed to be more closely related to termites than to other cockroaches, and current research strongly supports this hypothesis of relationships. All species studied so far carry the obligate mutualistic endosymbiont bacterium Blattabacterium cuenoti, with the exception of Nocticola australiensise, an Australian cave dwelling species without eyes, pigment or wings, and which recent genetic testing indicates could be a missing link between cockroaches and mantises.
Trachea and breathing
Cockroaches, like all insects, breathe through a system of tubes called tracheae. The tracheae of insects are attached to the spiracles, excluding the head. Thus cockroaches, like all insects, are not dependent on the mouth and windpipe to breathe. The valves open when the CO2 level in the insect rises to a high level; then the CO 2 diffuses out of the tracheae to the outside and fresh O2 diffuses in. Unlike in vertebrates that depend on blood for transporting O 2 and CO 2 , the tracheal system brings the air directly to cells, the tracheal tubes branching continually like a tree until their finest divisions, tracheoles, are associated with each cell, allowing gaseous oxygen to dissolve in the cytoplasm lying across the fine cuticle lining of the tracheole. CO 2 diffuses out of the cell into the tracheole.
While cockroaches do not have lungs and thus do not actively breathe in the vertebrate lung manner, in some very large species the body musculature may contract rhythmically to forcibly move air out and in the spiracles; this may be considered a form of breathing.
Like all insects, the cockroach nervous system is decentralized, with some functions distributed in the ventral ganglia. Though decentralized, the insect nervous system is fundamentally similar to that of vertebrates in terms of development, structure, and mechanisms of function. A decapitated cockroach can still walk and show responses to stimulation of its legs, as can a spinal-transected cat on a treadmill. However, a cockroach can survive complete decapitation for up to several weeks before dying of starvation or dehydration.
Eggs and egg capsules
Female cockroaches are sometimes seen carrying egg cases on the end of their abdomen; the egg case of the German cockroach holds about 30–40 long, thin eggs, packed like frankfurters in the case called an ootheca. The eggs hatch from the combined pressure of the hatchlings gulping air and are initially bright white nymphs that continue inflating themselves with air and harden and darken within about four hours. Their transient white stage while hatching and later while molting has led to many claims of glimpses of an albino cockroach.
A female German cockroach carries an egg capsule containing around 40 eggs. She drops the capsule prior to hatching, though live births do rarely occur. Development from eggs to adults takes 3-4 months. Cockroaches live up to a year. The female may produce up to eight egg cases in a lifetime; in favorable conditions, it can produce 300-400 offspring. Other species of cockroach, however, can produce an extremely high number of eggs in a lifetime, but in some cases a female only needs to be impregnated once to be able to lay eggs for the rest of her life.
Aside from the famous hissing noise, some cockroaches (including a species in Florida) will make a chirping noise.
Cockroaches are rather large insects. Most species are about the size of a thumbnail, but several species are bigger. The world's largest cockroach is the Australian giant burrowing cockroach, which can reach 9 cm in length and weigh more than 30 grams. Comparable in size is the Central American giant cockroach Blaberus giganteus, which grows to a similar length but is not as heavy.
Cockroaches are among the hardiest insects on the planet, some species capable of remaining active for a month without food, or being able to survive on limited resources like the glue from the back of postage stamps. Some can go without air for 45 minutes or slow down their heart rate.
Role as pests
Cockroaches are one of the most commonly noted household pest insects. They feed on human and pet food and damage and can leave an offensive odor. They can also passively transport microbes on their body surfaces including those that are potentially dangerous to humans, particularly in environments such as hospitals. Cockroaches infestations have been shown to be linked with allergic reactions in humans. One of the proteins that triggers allergic reactions has been identified as tropomyosin. These allergens have also been found to be linked with asthma.
General preventative measures against household pests include keeping all food stored away in sealed containers, using garbage cans with a tight lid, frequent cleaning in the kitchen, and regular vacuuming. Any water leaks, such as dripping taps, should also be repaired. It is also helpful to seal off any entry points, such as holes around baseboards, in between kitchen cabinets, pipes, doors, and windows with some steel wool or copper mesh and some cement, putty or silicone caulk.
American cockroaches have been known to live up to three months without food and a month without water. Frequently living outdoors, although preferring warm climates and considered "cold intolerant," they are resilient enough to survive occasional freezing temperatures. This makes them difficult to eradicate once they have infested an area.