I've got a neighbor that is 87 that told me to burn the needles of of Christmas trees before sinking them. Spread some of those spider buckets out on the shallow side of the dock heading towards the bank in all depths. You'll create a nice little rest area for them as they are on the move. There will be those that will make your dock their home, so having something for them to hide in from shallow to deep with help keep them there. Then make sure you invite me down to inspect all you hard work free of charge!