I've hunted deer for over 20 years almost exclusively with my 6.5" Blackhawk in .357. It is very effective inside 60-80 yards. Have also killed hogs and two black bear with the same gun. The blackies weighed 210 lbs and 390 lbs. Both were one shot kills, but in both cases they ran out 50 or so yards before dropping from shots that hit one or both lungs with one having also clipped the heart.
I handload 180 (or sometime 187) grain Cast Bullet Performance LBT Hardcast Solids over a stout dose of 2400. It's a "Ruger Only" type load that I would not recommend in many other .357's. It penetrates extremely well . . . through and through. Even had one go through a 350lb hog from neck to butt and exit.
Based on what I've seen, I have no problem hunting black bear with .357 from a tree stand. I would not prefer it for still hunting or bear defense vs. a .44 mag.