I opened a thread about this exact thing either last year or the year prior and there were a lot of mixed comments. What's weird is some years I see less in October and other years I don't. I think part of it has to do with certain crops being harvested or acorns dropping, etc.,. When those things happen could vary from year to year and both have a huge impact on deer movement. They are out there, just not always where you are. You have to go to where they are, that's part of our job as hunters. Scout, adjust, and you'll find them.
Maybe we as hunters just think it's a lull because we compare October to November, which has the most daytime movement, and December/Jan which is the easiest months to pattern deer hitting food sources. Just a thought
I think it has to do with a few things. 1. A change in preferred food source. Deer tend to gravitate towards hard such as acorns around this time of year. Another magnet for the deer are the soft mast (apples, pears, etc) 2. I believe the bucks have a change in their mind set. The start to separate from their bachelor groups and become more competitive and will spread out. 3. An increase in hunting pressure. They go 6-8 months with very little disturbances. Once hunters begin to hit the woods the deer become aware and tend to adjust their schedules accordingly. I don’t necessarily believe in the lull. That’s my opinion though so take it as you wish.