Do you see "Spiders" or "Robots" listed on the portal page with all the members who are currently online?
"Spiders" are automated computers (Robots) that "crawl the Web" seeking information to include in an indexed library used to give answers to search questions.
For example: Google sends a spider to Oldgas.com to watch for new information so that it can better give relevant results when the next person submits a search to Google about gas pumps or petroliana collectibles.
So it is a good thing that spiders visit. They are part of the process that organizes information on the Internet, so our site can be found by people seeking the info we have.