We hardly had any ATV's back then either. Now there's hundreds, if not thousands of them running around on NF. Craig Jourdonnais had some elk collared in the Bitterroot study going on, they were using NF lands until Labor day weekend. Then on that weekend most of the cows collared headed to the CB ranch. Why would that be? Wolves don't increase pressure on Labor day, but recreationists out running all over he!! do.
I don't this can be overstated enough. Roughly 6-700K ATVs are sold each year in America. Couple this with other factors such as the growth in foragers/mushroomers and you have more people in the hills creating anthroprogenic pressure on game.
I've spent 20 of the past 27 Memorial Day weekends in the same section of land in Washington. Up until about 10 years ago, we'd see more elk than people. This past Memorial Day weekend (consistent with the recent past) the hills were full of people that were camping, mushrooming, shooting (all day long!), riding ATVs and driving their cars and trucks along the roads. It is night and day how much more human activity there is in this area.
I've stopped many shroomers from going into a canyon that I know the elk calve in. I get the same reply everytime "I had no idea", no chit Sherlock you haven't been running these hills since 1982.
I can only imagine this little section of country is very similar to so many other areas in the west. Couple this with persistent drought and poor food supplies and it paints a pretty clear picture the other stresses that have been put on the elk.