HP
I've been watching this thread for a while and wanting to throw my couple pennies at the situation.
I've heard some folks warn about the tannins in certain wood harming their fish [was it oak or walnut - I don't recall] so please be careful and check around first before you use the oak unless you already know it's safe.
If you had a significant bass population, you wouldn't be seeing all those tadpoles IMO. Their prolific numbers suggest your fears on low LMB populations are correct.
I agree with the lack of aquatic vegetation you need some artificial structure. Cedars are great, and free - but consider PVC as well as it's snagfree, can be moved easily if need be, won't deteriorate, and is usually also free after posting a craigslist ad. PVC trees and globes in addition to Brettski Logs [see forum archives] are all easy to make.
Have you considered establishing some additional forage species? GSH need vegetation to spawn but perhaps with your GC hunting efforts you'll get some more vegetation back soon and stocked in dense enough numbers your GSH are fast/wary enough to escape predation long enough for the vegetation restoration.
Call Shawn Banks - he's in Polo MO and can source feed trained LMB, BG, GSH and anything else you may need. Plus, he's a Pond Boss brother and a somewhat cool guy.

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