I'm not sure why stripers have a low reproduction rate. Sand bass, which are evidently related, also spawn prolifically in running water and are numerous in all Texas lakes and river systems. I assume they are related since sand bass and stripers are crossed to make hybrids. Sand bass don't need much more than a decent creek to pull off a spawn. Could it be that they follow the rule that 'the smaller the animal, the more successful the spawn, hatch, etc.'?