Scientific Name: Polistes stigma.
Tamil Name: Kozhavi
Description: Paper wasps are long wasps that gather fibers from dead wood and plant stems, which they mix with saliva, and use to construct water-resistant nests made of gray or brown papery material. Paper wasps are also sometimes called umbrella wasps, due to the distinctive design of their nests.
Distribution and status: The total number of true paper wasps worldwide is about 1100 species, almost half of which can be found in the neotropics.
Habitat: The nests of most species are suspended from a single, central stalk and have the shape of an upside-down umbrella. Some tropical species make nests that hang in a vertical sheet of cells. The nests are constructed in protected places, such as under the eaves of buildings or in dense vegetation. Normally colonies of several to several dozen paper wasps inhabit the nest.
Habits: Most social wasps of the family Vespidae make nests from paper. Three species of Polistes are obligate social parasites, and have lost the ability to build their own nests, and are sometimes referred to as “cuckoo paper wasps“. They rely on the nests of their hosts to raise their brood. polistine paper wasps will generally only attack if they themselves or their nest are threatened. Since their territoriality can lead to attacks on people, and because their stings are quite painful and can produce a potentially fatal anaphylactic reaction in some individuals, nests in human-inhabited areas may present an unacceptable hazard.
Life cycle: The colony is founded in early spring, soon after the queens (mated females) emerge from hibernation. As the colony matures, males and the next year’s queens are produced. These queens mate with males and are the only members of the colony to survive through winter. In late summer or fall, the founding queen, workers (unmated females), and males all die. The newly mated queens hibernate, typically in piles of wood, in vegetation, or in holes. The following spring they emerge and begin the cycle anew. A similar life cycle is found in bumble bees.
Role in the environment: Most wasps are beneficial in their natural habitat, and are critically important in natural biocontrol. Because they are a known pollinator and feed on known garden pests, paper wasps are often considered to be beneficial by gardeners.
Photo source: http://en.wikipedia.org/wiki/Polistes_dominula