Mollusks are the second largest group of animals in the world. Mollusks include snails, slugs, clams,oysters and octopuses. Mollusks can be found on land, in ponds, streams, rivers, wetlands and the ocean. There are 1,571 native Hawaiian species of mollusks.

Some mollusks live in the ocean all their lives. Others are born in the ocean and migrate through the river to marshes where they mate. Mollusks live in shallow water and shore lines. This makes them vulnerable to the birds like Coot and Moorhen. After mating, they head for the ocean to lay their eggs. It is not known what species or even what types of mollusks can be found in the Hamakua Marsh. Further studies will focus on what species the Moorhen eats as well as what other types of Mollusks can be found in the canal and marsh.