With the middle name of Bird, G.B. Grinnell may have been destined to become an ornithologist, among other things. He grew up in Audubon Park in Washington Heights, Manhattan, on the 20-acre estate of John James Audubon, author of Birds of America. As a boy, Grinnell was fascinated with the preserved animal and bird collections, as well as the travels of Audubon and his son, John Woodhouse Audubon.
As a child, Grinnell had enjoyed seeing the flight of passenger pigeons from his bedroom window in New York, and he watched helplessly as the entire passenger pigeon population became extinct. Motivated by his desire to prevent the demise of other bird species, Grinnell helped found the first Audubon Society in 1886. It was officially incorporated in 1905 and named in honor of John James Audubon.
Grinnell studied ornithology and paleontology at Yale, graduating with a B.A. in 1870 and a Ph.D. in 1880. He worked as a graduate assistant at the Peabody Museum in New Haven. Grinnell initially specialized in zoology. In 1895, he helped found the New York Zoological Society – now the Wildlife Conservation Society based at the Bronx Zoo. But he later gained fame as an early conservationist and expert on Native Americans and the northern plains.
Grinnell spent years studying the natural history of the American West and became an expert on Native Americans, living with them for long periods of time. He wrote about the culture and destruction of the Indians, particularly the Cheyenne, Pawnee and Blackfeet Indians. He was pained by the destruction of the native tribal life by white settlers.
In 1870 he joined Lieutenant Colonel George Armstrong Custer’s cavalry as the official zoologist, and went on the Black Hills expedition in 1874. Luckily, he declined a similar expedition to Little Big Horn in 1876.
Grinnell lobbied Congress for the preservation of the American buffalo and conservation projects. Grinnell, a sportsman and hunter who understood the need to preserve wildlife, was friends with then President Theodore Roosevelt. They discussed the need for conservation, the preservation of American land, and laws creating and maintaining national parklands. He believed the national park system would help preserve and protect the landscapes, natural species and plants from miners, real estate moguls, hunters, loggers and tourists.