William Bartram (April 20th 1739, Kingsessing, Pennsylvania - July 22nd 1823) is a American Naturaliste , wire of John Bartram.

It accompanies his father in his many voyages, in particular in the mounts Catskill and in Florida. As of its young age, it has a perfect command of the drawing naturalist and in particular the botanical illustration. It also contributes to the maintenance of the Botanical garden created by his father.

In 1773, William Bartram only travels and explores Florida, the Georgia, the North Carolina and of the Southern. It collects specimens of the flora there and local fauna, draws it and is interested also in the Amerindian that it crosses there. It carries out the most complete list of Oiseau X of the United States of its time.

On its return, it publishes its newspaper (1791) under the title of Travels through North and South Carolina, Georgia, East and West Florida, the Cherokee Country, etc , who is regarded as one of the best works of Natural history of his time. Its account of voyage is strongly influenced by the romantic writers .

In 1802 Bartram meets Alexander Wilson, teacher and one of the founders of American ornithology, and starts to teach to him rudiments of Ornithologie.