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.
Some polar copepods reach 1 cm (0.39 in). Most copepods have a single median compound eye, usually bright red and in the centre of the transparent head; subterranean species may be eyeless. Like other crustaceans, copepods possess two pairs of antennae; the first pair is often long and conspicuous.