Garden Spiders (Argiope Aurantia) are commonly known as Writing Spiders or the Black and Yellow Garden Spiders. These spiders are identified by the distinctive yellow and black markings that are found on their abdomens, and an almost-white cephalothorax. They are found almost all over the United States, Canada, and Mexico, and are harmless to human beings as their bites only produce a sore, itchiness, and swelling, which heals in a couple of days.
If you want to look for garden spiders, then the right place to start would be areas adjacent to open sunny fields where they build their webs to stay concealed and protected from the wind. They are also found in outbuildings and tall vegetation. The female spiders can weave a web with a diameter as big as two feet at an elevation of about two to eight feet from the ground. These spiders do not tend to live in groups and keep their webs in a clean and orderly fashion. They also tend to remain at the same location for the entire summer, but may change places early in the season for want of a better location or food supplies.
The female garden spiders have distinctive yellow and black markings on their body along with bands on their legs. Despite their bright colors, these spiders are well camouflaged and can blend in easily with partially sunlit areas.
The female members of the species grow much larger in size as compared to their male counterparts. The male spiders have a thin body and can reach a maximum length of about 20 millimeters, while the females have a round body and reach a maximum length of 40 millimeters. The younger members of this species resemble the adults in every aspect except for the development of the reproductive organs and the length.
These spiders have three claws on each foot. The additional third claw helps them manage the strands of silk while they spin their webs.
Garden spiders reproduce once in a year. During the mating season, the males roam in search of a female and build a small web near or in the female's web and then start courting the female by plucking the strands of her web. Once they complete mating, the male spider dies and is sometimes eaten by the female spider.
The female spiders lay their eggs at night on a sheet of silk material and cover the eggs with another layer of silk. This layer is then covered with protective brownish silk. The spiders then use their legs to turn the sheet into a ball with an upturned neck. The egg sac can extend up to an inch in diameter. Each female spider produces one to four sacs with more than a thousand eggs in each. The sacs are then suspended from the web near the center, where the females spend most of their time protecting the eggs. However, over a period of time, the spiders become frail and die in the first hard frost of the season.
The young spiders exit the sac in the spring and are so tiny that they resemble dust particles. Some young ones remain nearby while others are carried away by the wind.
The webs of garden spiders are as distinctive as their body color. They are of a circular shape and can extend up to 2 feet in diameter. There is a dense mesh of silk in the center of the web which is known as the stabilimentum. It is used as a camouflage, attracting small birds and warning big ones about the presence of a web as otherwise the webs would not be easily visible. The spiders usually hang head-down while they wait for their prey to become entangled in the web.
Female garden spiders can oscillate their webs vigorously to ward off predators and entangle prey completely while remaining firmly attached at the center. As a daily ritual, they consume the circular interior of their web and rebuild it with fresh silk every morning. This helps them recycle the chemicals in their body which are used for building webs.