Those are probably YP ribbons but they may not hatch very well due to too much silt settling on covering the ribbons minimizing oxygenation of the developing embryos. You should try to drag one or two of those white things out for a closer look to verify perch eggs. Your pond water is so muddy that there might not be enough plankton for the fry to survive?

Last edited by Bill Cody; 04/07/19 08:12 PM.
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