Mild salintiy not only may help keep the striper eggs suspended in the water column but also Striper eggs have a large oil droplet or gobule which aids the bouyancy. Currrent then assists suspension of the egg downstream. I also have a hunch that the water salinity helps in egg development or viability of eggs and or milt. Keep in mind that the natural setting for these guys is life in the ocean and movement to freshwater streams for spawning. Development of fertile mature fish has to occur in a minimal amount of salinity conditions.

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