Roosevelt was the first president to make conservation a central policy of his presidency, protecting some 230 million acres in national parks, monuments, forests, and wildlife refuges. 

Roosevelt valued nature for its own sake, as a source of beauty and inspiration. He also valued it as habitat and as an economic resource. At a time when many viewed the nation's forests and wildlife as boundless, Roosevelt understood that they needed protection to last for future generations. 

Learn more about Theodore Roosevelt the Conservation President in the Theodore Roosevelt Memorial Hall.

Like many children, young Theodore collected bird nests and eggs, seashells, insects, and minerals. But Roosevelt, a precocious boy, measured and described his specimens. He took notes as he observed living animals and birds. 

As Theodore's interests matured, he visited the American Museum of Natural History often—both the exhibitions and the collections behind the scenes. At age 19, he published his first scientific work, a list of birds that he and a friend identified one summer in New York's Adirondack Mountains. 

Watch this video and learn more about Theodore Roosevelt as a Young Naturalist in the Theodore Roosevelt Memorial Hall.

An earlier phase of the Theodore Roosevelt Memorial restoration project included dividing in two the display mount of the famous Barosaurus and Allosaurus exhibit at the center of the Theodore Roosevelt Rotunda, allowing visitors to walk between the famous combatants for the first time. 

The mount is a dramatic representation of an imagined prehistoric encounter: a Barosaurus rearing up to protect its young from an attacking Allosaurus. The Barosaurus skeleton, which is the tallest freestanding dinosaur mount in the world, is composed of replica bones cast from actual fossils, which would be too heavy to support in this fashion.

When it reopens this fall, the fully renovated Theodore Roosevelt Rotunda—which is a New York City interior landmark—will also showcase painter William Andrew Mackay’s expertly conserved historical murals depicting significant achievements in Roosevelt's life. The murals are some of the largest indoor murals in a New York City public building, covering an area of more than 5,200 square feet. 

Born in New York City, Roosevelt had lifelong connections to the Museum. His father was one of the founders, and young Theodore often visited. Later, Museum scientists advised him on conservation policy. 

In this video, Museum Curator David Hurst Thomas; Roosevelt biographers Douglas Brinkley, Edmund Morris, and Patricia O'Toole; and Theodore Roosevelt IV discuss Roosevelt's lifelong association with the Museum and his conservation legacy. 

Douglas Brinkley, a professor of history at Rice University and author of The Wilderness Warrior: Theodore Roosevelt and the Crusade for America, the definitive biography of Roosevelt as a conservationist, served as a consultant for the Theodore Roosevelt Memorial Hall. David Hurst Thomas, a curator in the Museum’s Division of Anthropology, was the supervising curator for the hall, and Patricia O’Toole, Roosevelt biographer and an associate professor at Columbia University, also served as a consultant. Theodore Roosevelt IV is a Trustee of the Museum.

In the West, Roosevelt bought land in what is now western North Dakota, a stark landscape known as the Badlands, hoping to earn a living from cattle-ranching. There he learned firsthand how hunters had nearly wiped out bison, elk, and other large mammals. He also saw land damaged by overgrazing of cattle and came to understand the importance of managing water resources. 

Between 1884 and 1886, Roosevelt sojourned on horseback to the mountains west of Dakota territory. Few naturalists had described the wildlife of this region, and with the trilogy of books he wrote about his experiences, Roosevelt became an authority. 

Follow the Theodore Roosevelt timeline to learn more.

In the mid-1800s, the prairies teemed with tens of millions of bison. A few decades later fewer than a thousand remained. 

In this video, Ross D. E. MacPhee, curator in the Mammalogy Department and supervising scientist on the restoration of the Hall of North American Mammals, explains how both species featured in the American bison and pronghorn antelope diorama thrive today because of the careful efforts of Theodore Roosevelt and other committed conservationists. 

Roosevelt’s legacy is powerfully represented by many of the hall's stunningly restored dioramas, which depict landscapes and species that have been preserved in large part due to conservation policies he championed.

The restored Hall of North American Mammals is now open to the public.

Even before he began keeping natural history notebooks, Roosevelt started a boyhood natural history collection with his cousins, West and Emlen. Known as the "Roosevelt Museum of Natural History," the collection began with a skull of a harbor seal and grew to include animal skeletons, tadpoles, minerals, bird nests, and insects kept in young Theodore's bedroom.

Find out more about young Roosevelt's collection in the Theodore Roosevelt Memorial Hall, which includes never-before-displayed objects from the Museum's collection and interactive exhibits about his life.

At age 19, Roosevelt published his first scientific paper, The Summer Birds of the Adirondacks, with his friend Henry Minot. He began writing his first book, The Naval War of 1812, when he was a student at Harvard. He continued with two biographies, three books on ranching life, and the four-volume Winning of the West. Historian, essayist, and above all—a naturalist, Roosevelt published more than a dozen books before he became president. 

The Biodiversity Heritage Library's Theodore Roosevelt Collection includes books from the collections of the American Museum of Natural History. Selections are available on iTunes U.

While at Harvard, Roosevelt kept live snakes, turtles, and lizards in addition to ornithology books and taxidermy tools. In 1877, with classmate Henry Davis Minot, he published a leaflet listing 97 bird species they identified in the Adirondacks. The following year, Roosevelt won the respect of many ornithologists at the Nuttall Ornithological Club when he challenged their benevolent views about the English, or House, Sparrow and argued that this interloper was threatening native bird species. He backed up his thesis with detailed observations from the field.

The Snowy Owl returns to public view in the renovated Theodore Roosevelt Memorial Hall.

Florida’s Cuthbert Rookery, depicted in Hall of North American Birds, was habitat for egrets, roseate spoonbills, ibis, herons, and more. The site, located in extreme south Florida and now in Everglades National Park, was the scene of the 1905 murder of a game warden by commercial plume hunters. 

In response, President Roosevelt appointed more wardens in Florida and assured the Audubon Society that he was committed to ending the sale of endangered bird feathers for fashion.

At the center of the Theodore Roosevelt Memorial Hall, a new sculpture invites visitors to contemplate Roosevelt’s pioneering role in conservation and the vital importance of protecting nature today. Explore connections to the Conservation President on the Theodore Roosevelt Tour.

Throughout his career, Roosevelt sustained an intense curiosity about the natural world. When the Brazilian government invited him to join an expedition to chart an unmapped river, Roosevelt leaped at this chance to explore. 

Colonel Cândido Mariano de Silva Rondon, a Brazilian national hero, led the expedition. Naturalists from the American Museum of Natural History joined to collect birds and mammals. The group endured a harrowing journey: impassible rapids, malaria, and near starvation.

Learn more about Theodore Roosevelt the Lifelong Explorer in the Theodore Roosevelt Memorial Hall.

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