Spencer Fullerton Baird (1823-1887) was an American naturalist and ornithologist known for his significant contributions to the study of wildlife and the environment. He served as the second Secretary of the Smithsonian Institution, where he played a crucial role in expanding its research and collections. Baird was instrumental in establishing the U.S. Fish Commission, which focused on the conservation and management of fish populations. Baird's work included extensive studies on birds and fishes, and he published numerous scientific papers and reports. He was also involved in the early efforts of the National Museum of Natural History, helping to organize and curate its vast collections. His legacy continues to influence the fields of natural history and conservation.