This past week, I attended the winter lecture series at the Midewin National Tallgrass Prairie. The speaker was Frank Pascoe and the topic was spider watching.
Before you say eww … take note there were 30 to 40 other people packed in there to hear his presentation. Curiosity about nature is alive and well.
Identifying spiders can be tricky, but Pascoe helped us put them into categories by asking specific questions. Was the spider in a web, and if so, what did the web look like?
Many spiders make webs, but the structure and location of those webs can be vastly different. Did you see the spider crawling on the ground, and what time of day was it? Some spiders are more active during the day while others only come out at night.
What was the habitat you saw the spider in? Certain spiders like to live in the prairie, some prefer wooded areas, others you might find by a lake or river, and, yes, some do tend to be common in your house. The questions were many but if your goal is to identify and understand a given spider the answers will help narrow down the possibilities.
He talked a good while about spider courtship which, to me, was the most interesting part of the talk. Some species groups, like the jumping spiders, have large eyes and with great vision.
Pascoe had videos and pictures of their elaborate courtship displays where the males would dance in front the female. They even were able to somewhat sing. Large orb weaver spiders like those you might see in your garden or on the side of your house have very small eyes with weak vision.
The males, in this case, approach the web and pluck the silk strands in such a way that the vibration alerts the female that a male is there and ready to mate. There seemed to be a lot of pressure on these males because usually they are much smaller than the female, but also the vibration signal must be just right as to not be confused as prey.
On Inaturalist there are 227 different spider species listed for Illinois. When I consider how many thousands of moths or plants there are learning spiders doesn’t seem so daunting.
Pascoe was able to break them down into smaller groups that were easier to digest. I will be paying more attention in 2020 to the spiders around me, and I hope to join Pascoe in the field this summer to glean even more knowledge from him.