On our ship, each fish caught is dissected to remove the digestive tract, which is then stored for further analysis back in the laboratory in Basel. By the way, the fish are of course used for various other types of analyses. No part of the fish goes to waste. Our colleagues on board the Polarstern are taking blood and tissue samples from the liver, gonads, fins, muscles, eyes and the otoliths, which are small bones in the heads of the fish that help them with their balance.