Most cockroaches are tropical www.redully.com

 

Most cockroaches are tropical and sub-tropical in origin, generally live outdoors. They are mostly active at night, during which time they forage for food, water and mates. They may be seen in the daytime, particularly when a heavy population is present or when some other form of stress is placed on the population (such as lack of food or water). Cockroaches ordinarily prefer a moist environment, and many species also prefer a relatively high degree of warmth. Some tropical roaches feed only on vegetation. However, cockroaches which live in buildings are mostly scavengers and feed on a wide variety of food. They are especially fond of starches, sweets, grease, and meat products; but will also eat a great variety of materials such as cheese, beer, leather, bakery products, starch in book bindings, glue, hair, flakes of dried skin, dead animals and plant materials.

Cockroaches usually choose to live in protected cracks and crevices which provide a warm and humid environment. Some species, such as the American and oriental cockroaches, gather in large groups on open walls in protected places or in open areas outside. While they are often found in groups in their daytime hiding or resting areas (called "harborage"), and can be found feeding in groups at night, cockroaches are not social insects as are the ants and wasps. Cockroaches generally forage individually for food and otherwise behave in a largely individualistic or non-social manner. Even though cockroaches are not social insects, they do often form aggregates.

The general shape of a cockroach is familiar to everyone. They are oval and flat-bodied, which enables them to squeeze into all types of cracks and crevices. A pronotum (a shield-like covering) projects forward over the head; their mouthparts are of the chewing type and are oriented downward slightly toward the rear of their body. With their long spiny legs, they can run rapidly over most surfaces. Specialized pads in their tarsi allow them to easily scale glass windows or walk on a ceiling.

Besides their ability to move around inside and outside, and the fact that some species are good fliers, cockroaches are well known for moving to new areas via "hitchhiking." Because they prefer to hide in cracks and crevices in the daytime, they are frequently moved about by individual people or in products shipped around cities or the country. Careful inspection of furniture, clothing, or other goods coming into a home or other facility may reveal cockroaches hiding in these items. Careful observations by pest management professionals and researchers have shown surprising numbers of German cockroaches entering such facilities as hospitals, restaurants, zoos and supermarkets by these routes (every day in some cases).

Molting cockroach. Some people mistakenly think these molting individuals are "albino cockroaches."

Cockroaches develop by a gradual metamorphosis that consists of three stages: egg, nymph and adult. The female produces a purse shaped egg capsule, called an ootheca, which has two rows of eggs in it. Nymphs hatch out of the egg capsule by working together to break a seam along the top of the egg case. When the seam splits open, the tiny nymphs emerge to begin their life. The nymphs generally resemble the adult in appearance and behavior, but, are smaller, do not have wings or wing pads, and frequently have a somewhat different color. Newly molted nymphs are white, but will darken to the normal color within a few hours. Some people mistakenly think these molting individuals are "albino cockroaches."

Nymphs undergo a series of molts; with the last molt, the wings are fully formed and the sexes are easily distinguished from each other. Wings of the adults may be long and functional or short to almost nonexistent. In some species males are winged, but females have only small wing pads. Adults may or may not fly depending on the species and upon environmental factors. The length of time required for the eggs to hatch, for nymphs to develop, and the life span of adults will also vary (even within each species) due to temperature, humidity, the quality of their diet, and other environmental conditions.