Environmental Protection

Where Men No More May Reap or Sow

Conservation of marine birds of northern North America

Climate Change Is Racist

The Trail of the Sandhill Stag

The Barren Ground Caribou of Keewatin

Titan of Chasms: The Grand Canyon of Arizona

Atoms, Nature, and Man: Man-made Radioactivity in the Environment

Our Wild World

Nuova; or, The New Bee

The Underworld of Oregon Caves National Monument

Secrets of Earth and Sea

Whale Primer, with Special Attention to the California Gray Whale

Birds of the National Parks in Hawaii

Days to Remember

Between Earth and Paradise

The Enemies of Progress

Badgered to Death

Here For Our Children's Children

Curious by Nature

Storm Chaser