The egg mass is unusual among North American freshwater fishes. Eggs are bound into a translucent tube of gelatinous matrix, pleated along its length so it stretches and contracts, and a single ribbon from a large female can contain tens of thousands of eggs. She releases it in one prolonged spawning act, typically at night in spring, over drowned brush or weed in shallow water.
The structure appears to serve several ends at once. The matrix is unattractive to many egg predators, its folds allow water to circulate through the interior so the inner eggs receive oxygen, and the whole mass is anchored well off the bottom where silt would smother it. No parental care follows; both sexes leave.
Which of those functions matters most has not been cleanly separated by experiment, and estimates of how much the gelatinous coat actually reduces predation vary between studies and water bodies.