casca - Those are last years 2002 bass fingerlings. Bass you saw on the nest are producing the spawn of 2003. The fish you caught that went back to the nest was the male. He builds and guards the nest. The female just shows up for a brief time and deposits the eggs for fertilization. The male then hangs around for 20 to 30 more days trying his best to protect his offspring. Eggs may or may not have been in the current nest.
Those 3" bass are going to eat a lot of the new 2003 bass fry once they get out of the nest. You will notice this happening in about two or three weeks this if you spend some quiet time patiently observing life in the pond.

Can you go back out there and get us a surface water temperature? Take the temperature in the morning or in the shade if possible. Just use any air temperature thermometer just under the surface. Thanks

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