Northern Illinois is a mystery to me but I tend to think they use the rivers as travel paths and there may be some South-North (and vice versa) migration patterns there. Southern IL has large forests so no big surprise that there would be encounters. It's the same reason I get encounters in Iowa and Nebraska. The Missouri and Mississippi rivers (and tributaries) provide cover these creatures need. How do they get through Omaha? I have no idea, but there has been sightings there.
Texas is skewed high (at the moment) because the SSR contains reports from multiple organizations. I've been adding NAWAC reports the last several weeks. Some of these NAWAC reports are also listed with the BFRO, so there are duplicate entries for the same incident. We will be correcting this issue in the near future.
At present there are 226 BFRO reports for Texas and 211 NAWAC reports. I don't have the exact number of how many are duplicates in the SSR system now (more than 39, but less than 106), but I have identified 106 total encounters where NAWAC and BFRO report the same incidents. When we are done, each incident will only have one SSR entry and both BFRO and NAWAC will get recognition. In many of these, it was NAWAC investigators following up for BFRO.
Arkansas, Oklahoma, and Louisiana are also somewhat skewed for the same reason, although less progress has been made getting those NAWAC reports into SSR.
Edit to add BFRO only Sightings by State chart: