Thomas Mayo Brewer (November 21, 1814 - January 24, 1880) was an American naturalist.
Mayo is best known as the joint author, with Baird and Ridgway, of A History of North American Birds (3 volumes, 1874), which was the first attempt since John James Audubon thirty years previously to complete the study of American ornithology.
Brewer was born in Boston. He graduated from Harvard College in 1835 and from Medical School three years later. He abandoned his career as a doctor after a few years to concentrate on writing and politics, later becoming editor of the Boston Atlas. He then joined the printing firm of Swan & Tileston, which became Brewer & Tileston when he became a partner in 1857.
Brewer spent his spare time contributing to a number of ornithological publications, including John James Audubon's Ornithological Biography.
