When midshipman fish migrate from the deep Pacific waters to the west coast of North America each summer to mate, the intertidal zone becomes a noisy place. Courting males excavate nests beneath rocks in shallow water and hum to attract egg-laying females. The “love song,” described as a motorboat-like drone, comes from rapidly contracting muscles on the male's swim bladder and proves irresistible to the female midshipman. Each female deposits all her eggs for that season in one nest and swims away. Hoping to lure more females to the nest, the male resumes singing, all the while remaining on guard until the offspring hatch and mature.