Dolphin

"Social creatures of habit, dolphins can be found swimming together through the ocean in large groups. As they spot the player, they will try to interact with them, showing them just how highly intelligent and curious they are. Above all else – they are extremely playful!"

- Per Landin

Dolphins are neutral mobs that live in any non-frozen ocean.

Spawning
Dolphins are found in groups of 3-5 in all ocean biomes, except frozen oceans. Dolphins will continuously spawn as long as their spawn requirements are met, similar to squid. This is different from cows, for example, which will spawn upon map generation and then only rarely after that. 10% of them will be babies.

Drops
When killed, dolphins drop 0–1 raw cod (cooked cod if on fire), with the chance of an additional raw cod per level of Looting.

Behavior
Dolphins will normally swim in groups, occasionally leaping out of the water to get air. They're also able to jump from one body of water to another. They will also try to chase after players in boats.

Players who swim near dolphins will receive Dolphin's Grace for 5 seconds. In Bedrock Edition and Legacy Console Edition, the player simply gets a speed boost without a status effect.

Dolphins are lured by dropped items, knocking them around and chasing them. If the player or other mob hits a dolphin, the whole pod will retaliate, just like wolves and zombie pigmen attack as a pack.

Feeding dolphins raw cod will improve their "trust" with the player, depending on the amount of fish fed, causing them to interact with the player more.

When dolphins are fed raw cod or raw salmon, they will swim to the nearest shipwreck or underwater ruins. Because they are locating the chest in the structures rather than the structures themselves, breaking the chests will cause the dolphin to locate a new structure with intact chests. Dolphins also avoid guardians and elder guardians.

Weaknesses
If a dolphin leaves the water, it will start taking suffocation damage after a while (about two minutes), and eventually die like squid. When on land they will actively seek out a body of water.

They cannot survive without getting air every once in a while, so if they stay submerged for about four minutes they will begin drowning. The water breathing effect prevents them from drowning.

Dolphins cannot ride boats, similarly to squids and all types of fish.

Dolphins can be leashed and be pulled around with it.

Because the dolphin is an aquatic mob, they are affected by the Impaling enchantment.

Data values
Dolphins have entity data associated with them that contain various properties of the mob.

Trivia

 * To create the sounds that the dolphins make in the game, Mojang's lead sound designer, Samuel Åberg, went to Kolmården Wildlife Park to record real dolphins.
 * If a dolphin is beached on land and in a hostile state, it will move slowly towards its target.
 * Dolphins originally had a separate head and body when shown in a clip at MINECON 2017.
 * It is also shown in official artwork for Java Edition 1.13.