Palmer was born in Oakland, California and studied at the University of California. In 1889 he joined the Division of Economic Ornithology and Mammalogy of the United States Department of Agriculture under Clinton Hart Merriam. In 1891 he was a member of the 1891 Death Valley Expedition and its leader for its first 3 months. He was Assistant Chief of the Department from 1896 to 1902, and then from 1910 to 1914. He became interested in the legislation affecting wildlife, leading a branch of the organization to deal with it from 1902 to 1910 and from 1914 to 1916. He wrote the preliminary draft of the treaty for protection of birds migrating between Canada and the United States (1916), and was Chairman of the Committee which prepared the first regulations under the Migratory Bird Treaty Act (1918). He retired in 1933.