I think by removing the cover (plants) that the fry would hide in has helped the predatory fish eat more of the fry. If the GC have eaten the Chara, I'm pretty sure that they have eaten any other plants in the pond as well.

The large LMB could be getting hook shy, and the smaller ones (7" and under) could have been dinner for the larger LMB. If the LMB are full of natural forage, they will be less likely to strike at an artificial lure. Have you tried fishing live bait for them?

Bullets are not the best projectile for shooting fish in the water. Water is dense, dense enough to deform the bullet, and dissapate a LOT of it's energy in a short distance. If the angle is great enough, the bullet will ricochet off the water and not penetrate. I think you'll have better luck finding someone who bowfishes, or catch and remove the GC if they are feeding on pellets.

Have you caught any smaller BG (say 3"-5") from the pond?

How much cover is in the pond now? It sounds like the Chara and any other submerged pond plants were providing most of the cover in the pond.

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