Well they may not be ready for Red Lobster yet, but they’re smart
A series of shapes are projected on a screen, each shape symbolizes a different type of food. E.g a square means a mackerel and a cross means a squid. By aiming their echo location, to the shape projected on the screen, the dolphins can choose what they want to eat.
The Echo Location Visualization and Interface System (ELVIS) allows Dolphins to make choices and answer questions. Luna the young Dolphin grasped the concept quickest and is eager to choose her own meals and please her trainers.