I placed kiddie pools with road grade gravel in 24-36" depth and the BG/RES spawned on them last year. I don't think the bed installation is necessary, but it enabled me to monitor their behavior easier against the light colored gravel background as opposed to dark clay bottom. I used four pools 4.5' in diameter: 3 pools had one nest, 1 pool had two.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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