Ecology

Bird Day

Animals Without Backbones

The Chemical Age

The Sloth Lemur's Song

Power in the Wild

Why Birds Matter

The Mountains of California (With Original Drawings & Photographs)

The Periodical Cicada, “the 17-year Locust”

Literary Pilgrimages of a Naturalist

The Underworld of Oregon Caves National Monument

Snakes

Creation of the Teton Landscape: The Geologic Story of Grand Teton National Park

The Lobster Fishery of Maine

Man's Place in the Universe A Study of the Results of Scientific Research in Relation to the Unity or Plurality of Worlds, 3rd Edition

Journal of a Horticultural Tour

Hemp

The Climate Change Hoax: The Global Warming Deception

The Mountains of California (Illustrated Edition)

Summer

The Art of Migration