You'll see them out during the day, because there are too many to fit under the rocks. Grab as many as you want. You need a Utah fishing license, and remember you can't transport them alive. The bottom is mostly mud. Visibility quickly drops to zero if you're bottom-bouncing.
Smallmouth bass cruise the rocky areas.
We saw mostly babies. The lower visibility makes them hard to spot, unless you chum them in with bait and rock-clicking. Spearfishing is allowed in Steinaker, starting with the 2001 season. Eat all the crayfish you want. We haven't personally tried all the recipes on our Crayfish Recipe page.