Consider semi-circular. Cement blocks are a good idea for the perimeter. Some of the design - shape will depend on the placement area. IMO BG will utilize any shape of area as long as it has gravel sand mix. Size is IMO pretty much related to how big the pond is. Expect some beds to be made in 6" of water; most will be in 12"-2.5ft deep.

If the area is a small area I expect the beds to be slightly more crowded in a small spawn:surface area compared to a large ratio of pond surface area to spawn area. Number of adult BG will also have an effect on optimum spawn area size. BG are known to crowd their spawning beds together - beds almost touching each other. RES prefer less crowded bedding areas. BG recruitment could be reduced by downsizing it into a small spawn area. However with a too small of an area the biggest BG will dominate the best area and smaller mature BG will seek out other marginal areas to make beds. Making too small of an area would be like trying to keep teenagers from dating.

Last edited by Bill Cody; 01/14/17 03:33 PM.

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