I'm glad you replied to this topic, and we live in the same county. I was very busy during the deer season, and would only creep into specific areas to hunt. (Ohio this year)
The deer really became noticeable well after the season during the bitter cold. If the kill is fairly fresh, sometimes the body looks intact, and the butt area is bloody. I require my hiking girlfriend to photograph and determine cause of death if it appears to be a canine kill. Near public parks, humans might disturb them enough to stay off of the kill until a storm or cold front comes in. I assumed when the weather warmed up, the deer kill would slow down. Through the spring the adult deer kills were consistent. In march and April there were bucks that had shed antlers and doe that were killed next to a private lake. For over 10 years that seems to be a prime spot for them to kill. I assume the deer turn their back to the water?
Years back we saw a large coyote run by a glass door around 10pm. The tracks outside were large like a German Shepard. Following them in the dark sounded unsafe at the time. (Too young) It was on a remote 380 acre property in south east Ohio. The next morning, the large trotting prints joined a pack of 5-6+ coyote, and the track let to a kill 175 yards away. The only think left was a skull and a 10 point rack, and a front leg. Time lines are shaky, but I believe they ate the entire animal before spreading the bones that night. That has been the only observed pack kill crime scene. From video out there, one distracts while the other bites at the butt.
Even the bones don't last long, unless they kill another deer within a two week time. Fawns might be eaten whole. This spring I went hiking in Maine, PA, and Ohio over 3 weeks, and found 4 fresh but devoured kills; Tracks were used to locate.
You are right about the deer movement. No hunting pressure, or higher hunting pressure spread out seems to increase our odds. Moderate pressure is extremely challenging to deal with. Hunting in Butler county, I remember the deer getting pushed to each segment of woods. To cause a deer stress when it has access to safe cover is a recipe for nocturnal activity. In the foothills around Ohio they bed at the tops of cliffs, and rarely present a clear shot.
I haven't worked around the park rangers or commission workers in awhile, so am not sure about what their current strategy is. It appears they are treating pheasants like trout. For years away, and release birds that are about as durable as a chicken. We used to complain that the birds wouldn't even try to get away. The months between hunting seasons, I guess it would be possible to see a straggler that had been released. The farther away from game lands you are, the more unlikely this is. When the trout season is over, there certainly very many trout. One Waterways conservation officer explained to me (12 years ago) that the trout don't need to be able to eat or survive in those streams (although a few might) they are just there to be caught.
Makes you wonder if it's the genes, or somewhat bad genes and hen kills. People used to see domestic cats catching the released birds.
The solution to this problem is fairly simple, but they probably aren't willing to do it. The cost in the end will be our original bird genetics. A few imported wild birds that aren't hunted would be a good start.
Sorry for the scattered reply, this phone is bouncing around the image.