The Medieval Pelican
The pelican of the Middle Ages was thought to pierce herself in her breast in order to feed her blood to her young. Alternate stories tell of how the pelican would kill her young in a fit of pique, and then pierce her breast in later remorse. The blood thus brought forth, falling on the dead chicks, brought them back to life.
Generally, depictions of the pelican are meant to indicate Christ the Saviour who shed his blood in a like manner.
In medieval heraldry, a pelican is an eagle-beaked bird always shown plucking at her breast. If shown alone she is blazoned (described in heraldic terms) as "vulning herself". If the young are shown with the parent, she is blazoned as "a pelican in her piety".

The Physiologus, and later Latin Bestiaries of the Middle Ages, found the action of the pelican, so interpreted, as a particularly appropriate symbol of the sacrifice of Christ the Redeemer shedding His blood, and thus the symbol of the pelican grew to have a wide usage in Christian literature and art. Thomas Aquinas did indeed use the figure of the pelican in his beautiful hymn appointed to be sung in Thanksgiving after Communion, the Adoro Te Devote:
"Pie Pellicane, Jesu Domine, Me immundum munda Tuo sanguine. (verse 3) O Loving Pelican, O Jesu Lord, Unclean am I but cleanse me in Thy blood."

In medieval and baroque art, the pelican is often found as an ornament on altars, chalices, and tabernacle doors. The image of the bleeding mother bird appears frequently on coats of arms in heraldry, including the seal of the State of Louisiana.