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.
These are called tertiary consumers. A typical marine food chain could look like this: In this example, the phytoplankton is the producer, the zooplankton is the primary consumer, the small fish are the secondary consumers, and the squid, which eats the small fish, are the tertiary consumers.