The life cycle of fishes and other marine organisms is extremely complex and one blog entry is surely not enough to elaborate this topic. But regardless of the season and dive sites, we can usually see several marine species and their eggs whilst diving in Lembeh. Normally, marine organisms produce large amounts of small eggs that hatch quickly. This produces large populations and therefore a greater chance for species survival.
Take this female Mantis Shrimp for example which must have carried thousands of tiny little eggs. She will provide maternal care by using her maxillipeds to clean the eggs and circulate water around them. After the eggs hatch, the larvae will leave the burrow. They are planktonic and will go through several stages of development before becoming adults.
This is quite different with Cardinal Fish – they can be considered modern males of the sea! It’s him who carries all the eggs in his mouth for weeks. Being mouth brooders, male cardinal fish are not able to eat until the eggs have hatched. During this time, the Cardinal Fish will open its mouth and occasionally rotate the eggs to keep them clean and aerated. And this is what is interesting to photograph if you have a 60mm (or even better 105mm) macro lens and a little bit of patience.