Sources : Pelican

Aristotle [ca. 350 BCE] (De animalibus, Book 8, 14.2; 9, 11): [Book 8, 14.2] The pelicans also are migratory, and leave the river Strymon for the Ister, where they rear their young. They depart in great crowds, and those that are before wait for those behind, for in flying over the mountains those behind cannot see the leaders. [Book 9, 11] The pelicans, which inhabit the rivers, swallow large smooth shells with their drink, and when they have been digested in the first part of their stomach, they vomit them up, in order that they may pick out and eat their flesh when they open their valves. - [Cresswell translation, 1887]

Pliny the Elder [1st century CE] (Natural History, Book 10, 66): Pelicans have a resemblance to swans, and would be thought not to differ from them at all were it not that they have a kind of second stomach in their actual throats. Into this the insatiable creature stows everything, so that its rapacity is marvelous. Afterwards when it has done plundering it gradually returns the things from this pouch into its mouth and passes them into the true stomach like a ruminant animal. These birds come to us from the extreme north of Gaul. - [Rackham translation]

Isidore of Seville [7th century CE] (Etymologies, Book 12, 7:26): The pelican [pelicanus] is an Egyptian bird inhabiting the solitary places of the river Nile, whence it takes its name, for Egypt is called canopos. It is reported, if it may be true, that this bird kills its offspring, mourns them for three days, and finally wounds itself and revives its children by sprinkling them with its own blood. - [Barney, Lewis, et. al. translation]

Thomas of Cantimpré [circa 1200-1272 CE] (Liber de natura rerum, Birds 5.96, 5.98): [Thomas describes the pelican under the names osina and pellicanus.] [Birds 5.96] Osina is a large bird like a swan. It inhabits rivers and ponds. It has a big and strong beak. They are fond of preying on fish, which they pass into their bodies with their beaks, and it seems that nature has given them the means to take fish so convenient for their bodies. For they have a large and long receptacle, like a bag, from the very throat to the breast, in which they store a great quantity of fish at the same time. And see how fittingly it is that nature does not require that it be spread out in so great a mass, and that, after being gradually digested, it should find inwardly prepared in the belly of the fish what it would supply with nourishment. Nowhere are birds of this kind numerous, except wherever the water is more diffused and there is a great abundance of fish. For they very quickly empty a little water, even if it is abundant, with their fishing. [Birds 5.98] A pelican is said to have (as it were) a gray skin. Hence, Augustine and Isidore say, that they have gray feathers. This bird lives in Egypt; it is most frequented around the Nile. This bird, though she loves her chicks, when at last they were intrusive to her, kills them, and when she has wept for three days, she strikes herself in the side with her beak and revives them with her own blood. And it is said that they do this very thing, when they have found the chicks killed by a snake that lies in wait for them. The Experimentator says of this bird that after the shedding of blood, the pelican is weakened and she is unable to leave the nest, so the chicks are forced to leave the nest to get food her her and themselves. In some cases, however, the chicks are cowardly, so that they do not want to go out to feed themselves or their mother, and perish. Others, however, go out and feed their mother. But others are worse, who indeed feed themselves, but completely neglect their mother. When the mother after her recovery sees this, she nurtures pious children, but casts away and despises the impious. There are two kinds of pelicans. One is aquatic, which lives on fish; but the other lives on the land and feeds on snakes. The pelican also lives on the milk of the crocodile, which, of course, having an excessive abundance of teats, casts out milk in great quantity in a certain marshy place. Hence the pelican gladly follows the crocodile. Philosophus: This bird is always lean, and quickly digests whatever it swallows, because its stomach has no opening to hold food; for it has only a visceral duct, which reaches from the entrance of the mouth to the secret nature [?]. This is done in Lycia, Greece, says the Liber Kyrannidarum: the birds that eat meat and those that do not, wait for one month, divided into armies on each bank of the river. And when the assembly is done, a cry is raised to heaven, and they fly and fight in such a way that much blood is shed and much plucking takes place, whereupon the Lycians spread their nets; among these and the pelicans there is a great multitude, armed with spears. - [Badke translation/paraphrase]

Bartholomaeus Anglicus [13th century CE] (Liber de proprietatibus rerum, Book12.29): A Pellican is a Birde that is called Porphitio. Levit[icus] 11. and Deut[eronomy] 14. And is a Birde of Aegypt, and dwelleth in desart, beside the River Nilus: and is accounted among uncleane birdes by the lawe in Levit[icus]. And there be two manner of Pellicans: One dwelleth in water and eateth fish, and the other dwelleth on land, and loveth wildernesse, and eateth venimous beasts, as Lisardes, and other such. And all that the Pellican eateth he plungeth in water with his foote, & when he hath so plunged it in water, he puteth it in his mouth with his own foot, as it were with an hand. Only the Pellican and the Popiniay, among foules, use the foote in stéed of an hand. Also of the Pellican, the Glose speaketh super Psalmum, & the same Plinius saith in this manner. The Pellican loveth too much her children. For when the children bée haught, and begin to waxe hoare, they smite the father and the mother in the face, wherfore the mother smiteth them againe and slaieth them. And the thirde daye the mother smiteth her selfe in her side that the bloud runneth out, and sheddeth that hot bloud uppon the bodies of her children. And by vertue of the bloud the birdes that were before dead, quicken againe. And in the Glose upon that place of the Psalme. Factus sum sicut Pellicanus. It is sayd that the Pellican slayeth her Birdes with her bill, and maketh sorrowe thrée dayes, and then sheddeth her hot bloud uppon them, and maketh them alive againe in yt manner. Magister Jacobus de Vitriaco in li. de mirabilibua orientalium regionum telleth another cause of the death of Pellicanes birdes. Hée sayth, that in Aegypt is a bird yt is called Pellicanus, a Birde with greate wings, and most leane. For all that he swalloweth passeth forth anone behinde: for hée hath a right slipper gut. And therefore hée maye not holde meate till it be incorporate. And the Serpent hateth kindlye this Birde. Wherfore when the mother passeth out of the neast to get meate, the serpent climeth on the trée and stingeth & infecteth the Birdes. And when she commeth agayne, shée maketh sorrowe thrée dayes for her Birdes, as it is sayde. Then (he sayth) shée smiteth her selfe in the breast, and bringeth bloud uppon them, and reareth them from death to lyfe, and then for greate bléeding the mother waxeth féeble, and the Birdes bée compelled to passe out of the neast to gette themselves meate. And some of them for kinde love féede the mother that is féeble: and some be unkinde and care not for the mother, and the mother taketh good héede thereto, & when she commeth to her strength, she nourisheth and loveth those Birdes that fedde her at her néed, and putteth away her other birdes, as unworthye and unkinde, and suffereth them not to dwel nor live with her. - [Batman]