Unlike mammals, birds do not produce milk for their young to consume when they first hatch. For this reason, the youngsters require food prepared in such a way that they are able to digest it.

The strategies vary but always involve food broken down into small enough pieces that the young can swallow and digest it.

Many species regurgitate partially digested food for the young to consume. Some of the famous examples of this include Penguins and some seabirds such as Albatrosses. In other species such as Puffins, the young are fed smaller fish. In the case of raptors, the food is torn up into smaller pieces in order to make it digestible.

Of all these methods however, regurgitation is the most extreme method of preparing food for the young chicks.