I have never noticed my herd changing one way or the other. However, this year, this cow has kept more to herself and less with the herd for some reason - not like in the past. Went out today (now waiting on the last calf to hit the ground), and she watched me the entire time, even while not near her baby, only moving toward him when I drove over to check all the calves. I got out of the truck (not too near the baby) just to see what her reaction would be. She walked toward me then saw I didn't have a feed bucket, so she lost interest. I have 6 babies less than a week old; all of them were together with a couple of babysitters. When I drove by, the babysitters stood up and got between me and the calves. I have good mamas, I think.
Not having a good eye for buying cattle, I have an older friend/mentor who buys them for me. My instructions are always to find gentle/low-maintenance bred cows. He has always come through. This was just different behavior for this cow, but I think I caused it. When I found the cow and baby, I took the first photo and all was well. Then I walked around the area for about 5 minutes, then back to take another photo. I think the second time was just too much for this nervous mama. Still don't know why she has not hung with the herd as much this year.