Much like our friend the seahorse, the males of this fish raise the young. As you can see in the photograph above, the male has his clutch of eggs in his mouth. This species (Opistognathus whitehurstii) of fish are mouthbrooders—or more simply, they raise the eggs in their mouth. The eggs typically stay in the mouth for 8-10 days. When eggs are not in their mouth, the fish can burrow with it, ingesting sand and spitting it back out to make a tunnel.