Summary of Observations of Araneus pratensis, openfield orbweaver, at Barnes Tallgrass Prairie Remnants, Racine Co., WI. in 2023

Araneus pratensis, a small, colorful orbweaver, has historically been found on segments of the original tallgrass prairie in Racine, Kenosha and Walworth Counties which was known as Barnes Prairie, as related to me by neighbors when I was a child. Neighbors, relatives and friends of my family, living in Racine and Walworth Counties, whom I interviewed in the late 1950s as a child, called this spider the “little, colorful web spider” or a “red and orange striped small web making spider”. Two of the women I interviewed told me that they were common along the (unmown) roadsides, between unplowed fields, and in the wildflower fields (original tallgrass prairie remnants).
Due to development of these lands to housing, highways, industry and commercial business over the last 50 years, only a few areas of native tallgrass prairie remained as of 2023. My surveys were at several of these now-degraded native tallgrass prairie remnants in Racine County.

Habitat
Araneus pratensis were typically found in drier areas of the prairie where shorter grasses and forbs were predominant. Gray dogwood and prickly ash were often seen in these areas. Areas of goldenrod, white gentian, common milkweed, aster and taller grasses also held populations of these small arachnids.

A Total of 45 Spiders were seen and photographed in late summer and early fall, 2023. Photos were taken during the day, from early morning to late afternoon.

Date, No. of Spiders
Aug. 30, 2023, 1
Sept. 7, 2023, 1
Sept. 9, 2023, 5
Sept 16, 2023, 18
Sept. 18, 2023, 9
Sept. 20, 2023, 5
Oct. 2, 2023, 3
Oct. 18, 2023, 1
Oct. 24, 2023, 2

Web anchor plants
Plants that webs, with spiders on them, were attached to, included short grasses, goldenrod leaves and grasses, webs connected to common milkweed leaves and between a gray dogwood leaf and grass. Several spiders were found on common milkweed pods, not on their webs.

Web hub/center height and comments
Heights varied, with the shortest being about 7” from the ground. Many were between 9 and 14 inches from the ground. Highest hubs were seen between 28 and 32 inches from the ground.
Two webs with A. pratensis were located adjacent to the webs of Argiope trifasciata. One of these was connected to the same blade of grass that the banded argiope web was anchored to.

Prey
On October 16, a number of winged ants were seen in webs. Also seen were unidentified small flies.

Publicado el 10 de noviembre de 2023 por bkis