We don't catch more because the DEC pulled the spring water rod and gun clubs permit to stock walleyes due to the fact that their research program concluded that the people that fish the lake would rather fish for rainbow trout than walleye. Natural spawning is limited due to the amount of predators(alewives) eating young walleye, amongst a variety of other factors.
I use my m18 fuel hammer drill(brushless, 4amp hour battery) using the 10$ strike master adapter bit and a 6" lazer. Only time I've killed both batteries was drilling 50+ holes through 2 feet of lake Erie ice
Not at a rate sufficient to support a self sustaining population, but there's no reason to believe that there haven't been a few that have successfully spawned.
I want to say the late nineties to early 2000's was the last time they put eyes in there. If you ever see the gentleman with the white c-dory he can tell you all about it. I believe his name is Charlie, he has detailed journals and has boated several hundred hemlock eyes. He said he paid for most of the eyes that were stocked.
Nice fish! Just take into consideration that the hemlock bow fishery is self sustaining with no stocking so throwing a few back now and then will only help the fishery.