Sometimes they rest buried in the sand in shallow water. They extend their necks and use their long noses as snorkels. They hunt during the day. They are capable of exchanging gas through their skin in both water and air. Spiny softshells breed in May and they lay their eggs in June or July.
Females usually dig nests on sand bars that receive sunlight.
Carnivorous mammals, however, dig up most of the nests and eat the eggs. The brittle shelled eggs are the shape of, and a little smaller than, ping-pong balls. The young hatch in August or September. Hatchlings overwintering in the nests have not been observed in Minnesota. The young are patterned like adult males, and have up turned noses and the sides of the carapace droop covering the hind limbs and tail like a blanket.