This pair of fish was building a nest at night. It was about 8 P.M., and we were diving in water about 40 feet deep near the island of Bimini . The fish would take turns swimming to the nest. First, the female would lay eggs in the nest, and then the male would fertilize them. The nest contained many thousands of eggs when they were finished.
Young fish are easy prey for larger fish.
The coral reef is a very competitive place. There are hungry fish everywhere. That's why it takes thousands of Sergeant Major eggs to guarantee that a few of the fish will survive to become adults. After building this nest, the male Sergeant Major will stay near the nest for several days to guard the eggs until they hatch. The female will leave during this time.