Mating Behavior. Every 2 weeks during the new and full moon high tides (called spring tides), the females come out of the water, often dragging a male attached to her with his hook-like front legs. On the beach she will dig a hole in the sand beneath her to lay her eggs. As she lays her eggs, the attached male (or males) release sperm to fertilize the eggs. The eggs develop under the sand for 2 weeks until they hatch just in time to catch a ride out on the next high tide. A female may lay as many as 80,000 eggs per season.