The Life Cycle of Paper Wasps

Humans are not the only ones to have discovered the uses of paper; the aptly named paper wasp processes and utilizes wood fibers to build their homes. Identifiable by their smoky wings and slender body, paper wasps (order Polistes) are beneficial insects that feed on common pests such as caterpillars and beetle larvae, as well as houseflies and blowflies. However, they are quick to defend their home and young, and will repeatedly sting anyone who disturbs their nests, commonly found hanging on the underside of leaves.

Paper wasps are semi-social insects; they are broken into three castes: a fertile queen, sterile workers, and a male. After mating with a male paper wasp, fertilized queens overwinter in protected shelters such as in cracks in bark or logs, and sometimes even in stacks of firewood. The queen then emerges during the warmer months of spring, and immediately builds a nest made of chewed wood pulp. Eggs are laid in the hexagonal cells of the constructed nest. The larvae that emerge soon after are raised by the queen. After the first generation of paper wasps emerge from their pupae stage, they become the workers of the nest, and the queen no longer plays any role other than producing more eggs.

The sterile workers serve both to expand the nest and to raise the larvae. Although the workers themselves are unable to eat solid food and feed on insect nectar, the larvae feed on caterpillars and insect larvae, which are caught and chewed by the workers. The larvae go through several developmental stages known as instars, until finally entering their pupae stage. After remaining in the pupae stage for nearly two weeks, they finally emerge as mature adults. In total, it takes around two months for the paper wasp to transition from egg to adult. Ironically, paper wasp larvae are often the main providers of food for the queen, who wags her abdomen across the nest when she is hungry to “beg” the larvae to secrete nutritious salvia.

At its peak, the paper wasp nest has around twenty to thirty individuals, and the size of the hive rarely exceeds two hundred insects. A paper wasp colony usually lasts around six to seven months. If the queen dies prematurely, the role can either be taken over by the most dominant worker, or a “sister” of the queen that was unable to establish its own nest.

Although most eggs develop into workers, a few develop into gynes. These wasps tend to emerge later in the year, and are distinguished from workers by the extra body fat they store, allowing them to survive the winter. After emerging, gynes fly off to seek mates, continuing the cycle again.

For more information,visit http://insects.tamu.edu/fieldguide/cimg348.html