After reflecting on this since first posting and reading some of the comments, I'm thinking now the nets might do more good than harm. It seems that the carp spawn at the same time as the white perch. How many times have you seen the huge carp rolling all along the bank line chasing each other when you're trying to fish shallow? That's got to destroy a lot of crappie eggs. Reducing the number of carp would probably make for a better perch spawn.