Add butter/olive oil combination. Add the fillets, without crowding. Increase heat to high and saute, shaking the pan from time to time, until the bottom of the fish is nicely browned, about 3 minutes. Turn and brown the other side. Remove fish to a plate and keep warm in the oven. Repeat with remaining fillets.
Copepods are considered to be primary consumers. They form an important link in the food chain. Their diet consists of small plant plankton.
Barnacles, amphipods, isopods, and copepods are also Crustaceans. Crustaceans have five pairs of appendages. Usually the front pair, called Chelipeds, have claws on them, while the remaining four pairs are walking legs. In many species, the second and even the third pairs of legs have smaller pincers on them as well.