Does anemonefish actively feed its hosts in the wild?

Living symbiotically with sea anemones that shelter them from predators, anemonefish (Amphiprion clarkii) drive away organisms that nibble at their hosts. Anemonefish have also shown they will provide their hosts with the food given to them by humans. A new study shows such feeding behaviour does happen in the wild by investigating food provisioning by anemonefish and its effects on the symbiotic relationships. When anemonefish are provided with foods of various sizes and types in the field, they selectively consume small animal food (krill, clams, squid, and fish) and green macroalgae of small size, while providing larger pieces of animal food to their hosts. Additionally, the anemonefish avoided either eating or providing brown macroalgae and sponges to the host anemone, which appeared to be unsuitable as food for both anemonefish and sea anemones. For smaller food, the fish had their fill first before feeding the sea anemones. Food provisioning positively influences the growth of host anemones as growth of anemones directly benefits anemonefish — the number of eggs laid increases when the hosts are larger and since anemonefish cannot leave their sea anemone, feeding their hosts is extremely important. Thus there is evidence which suggests that anemonefish actively provide food to host anemones based on the situation.