When Meriwether Lewis and William Clark set off up the Missouri River in mid-May of 1804 with their 26-man contingent (3 sergeants, 22 privates, and Clark's slave York) and about 10 additional boatmen and interpreters, they had no detailed knowledge of what lands or adventures lay before them. When the group returned more than two years later, in late September of 1806, they had made more discoveries of landscapes, rivers, native cultures, zoology, and botany of our continent than has any North American scientific expedition, either before or since. They traversed upstream across the entire Great Plains region, which for present purposes is defined as including that part of the Missouri Valley between the current Missouri-Kansas border and the vicinity of Three Forks, Montana, where three mountain-fed rivers merge to form the Missouri. By the time they reached what is now western Montana in late July of 1805 and were about to challenge the Rockies, they had already ascended nearly 4,000 feet of elevation. They also had explored and carefully described roughly 2,500 river miles of the Missouri Valley since leaving the Mississippi River, a task that by itself represents a heroic if not Herculean physical effort.
Over the 14-month period during which the explorers crossed the Great Plains on their way to the Pacific they collected specimens of plants later found to represent at least 20 new species, not counting an unknown number of additional specimens that either were lost or damaged beyond repair in the course of the expedition or have disappeared from any present-day museum or herbarium records.
Lewis and Clark also discovered or carefully described for the first time at least seven Great Plains species of mammals, including the pronghorn, grizzly bear, swift fox, black-tailed prairie dog, white-tailed jackrabbit, bushy-tailed woodrat, and mule deer. The Columbian ground squirrel was first encountered, and thus discovered, in western Montana, but it was not carefully described until after the group arrived in Oregon. Several Great Plains birds representing new genera (depending on the taxonomy source chosen) were described for the first time, including the greater sage-grouse, common poorwill, McCown's longspur, and Lewis's namesake species, the Lewis's woodpecker. The woodpecker, whose previously unique genus Asyndesmus has recently been merged with Melanerpes, was first seen along the edge of the Big Belt Mountains near present-day Helena, Montana. However, this woodland-edge woodpecker was not actually collected until the following spring, near Kamiah, Idaho. A skin of the Lewis's woodpecker is in Harvard University's Museum of Comparative Zoology and is perhaps the only remaining intact museum specimen of all the animals collected during the expedition. The least tern was also carefully described and measured, based on two specimens they had shot. There can be no doubt that these five species of birds, at minimum, were discovered by Lewis and Clark on the Great Plains.
In his valuable summary of the natural history of the entire expedition, Paul R. Cutright listed a total of 30 then-undescribed vertebrate species or subspecies that were noted by Lewis and Clark during the Great Plains phase and possibly as many as 9 additional ones that were encountered but not adequately described to identify them with certainty. Virginia Holmgren more recently summarized the bird discoveries of the entire expedition, listing 25 that she believed were sufficiently well described to warrant "discovery" status, 9 species that might have been considered as newly discovered if they had been better described, and 11 species that were already well known by some common name but had not yet been formally described and named scientifically. In the category of definitely discovered Great Plains birds, she listed the trumpeter swan, greater sage-grouse, semipalmated plover, mountain plover, upland sandpiper, long-billed curlew, least tern, common poorwill, Lewis's woodpecker, Sprague's pipit, McCown's longspur, western meadowlark, and Brewer's blackbird. Of these, the mountain plover and upland sandpiper are distinctly questionable as to their identification. There is no evidence that the highly elusive Sprague's pipit (Anthus spragueii) was ever seen, and the "small Kildee" observed along the Missouri River was probably the piping plover rather than the migratory and arctic-breeding semipalmated plover (Charadrius semipalmatus). The identities of several Great Plains shorebirds mentioned briefly by Lewis and Clark, such as the mountain plover and long-billed curlew, are especially problematic, as they used terms like "plover" and "curlew" rather indiscriminately for shorebirds generally. The tundra swan (Cygnus columbianus) (previously known as the whistling swan) was initially described from observations made by Lewis and Clark during the Pacific-slope phase of their expedition, but it or the trumpeter swan was seen earlier in what is now North Dakota. The trumpeter swan is the semiresidential breeding swan of the northern plains, whereas the arctic-breeding tundra swan is a spring and fall migrant only. Thus, the chances of their having seen the trumpeter swan on the northern plains were fairly good. At least eight previously unknown species—the trumpeter swan, greater sage-grouse, piping plover, least tern, common poorwill, Lewis's woodpecker, McCown's longspur, and western meadowlark—are well enough documented to count as having certainly been seen by Lewis and Clark, and the greater sage-grouse, least tern, and Lewis's woodpecker were as carefully described as any practicing ornithologist of the day might have done.
Among reptiles and fishes, the western rattlesnake, western hognose snake, cutthroat trout, blue catfish, channel catfish, goldeye, and mountain sucker are certain or likely to have been newly discovered species. Several Great Plains mammal and reptile species that were known but only poorly documented, such as the bison, gray wolf, coyote, western garter snake, and bullsnake, were described by Lewis and Clark to a much greater degree than previously known. Many other plains animals that later were determined to represent new subspecies of previously known species were described, or at least mentioned, for the first time.
For the trip collectively, nearly 100 previously unknown species or subspecies of vertebrate animals were encountered and variously described by Lewis and Clark, judging from a recent summary by the Sierra Club. About 40 percent of these now have a state- or federal-level designation indicating that active protection or conservation concern is warranted. Of these, 13 species are now classified as nationally endangered, including such classic Great Plains animals as the gray (prairie) wolf, whooping crane, and the interior race of the least tern. Great Plains species that were seen by the expedition members but are now federally threatened include the piping plover and grizzly bear. In the past two centuries the grizzly bear has changed from being the commonest large carnivore of the upper Missouri Valley to having been completely eradicated from it. Similar comments might be made of the gray wolf and the whooping crane.
Cutright listed a total of 22 new plant species collected by Lewis and Clark during their journey upstream between the mouth of the Kansas River and the vicinity of Three Forks, Montana. They include such plants as Indian tobacco (a species not native to the northern Great Plains), curly-top gumweed, and three species of sagebrush. A surprising number of the plants they collected were species believed by Native Americans to possess medicinal or other functional properties, and thus were very familiar to and highly valued by the tribes of the upper Missouri Valley. Most of them are now considered only to be weeds, and none is listed as threatened or endangered.
The expedition's return trip across the Great Plains in 1806 was entirely downstream and consequently much faster, thus accounting for the expedition's far fewer zoological or botanical discoveries. However, at least five Great Plains plants collected during the return trip were later described as new species, according to Cutright. These included salt sage, red false mallow, gumbo evening primrose, black greasewood, and snow-on-the-mountain. These discoveries primarily consisted of plants obtained by Captain Lewis while exploring the upper Marias River valley of northwestern Montana. Although no new plants were obtained, several new topographic features and some significant wildlife observations were documented by Captain Clark on his separate route down the Yellowstone River.
Frederick Pursh initially examined 155 of the roughly 200 plant specimens that successfully made their way back to the safety of the American Philosophical Society collections in Philadelphia. At the time he published his studies (1814), he classified four of the Lewis and Clark specimens as representing new genera and 123 as new species. A recent summary by James Reveal, Gary Moulton, and Alfred Schuyler indicate that Pursh associated the Lewis and Clark materials with 132 botanical names, 94 of which were newly proposed by him and nearly all of which were taxonomically valid. These authors also determined that Lewis and Clark collected at least 202 different kinds of plants. However, many of the Lewis and Clark specimens have since been lost. If all the plants encountered and variously described but not necessarily preserved by Lewis and Clark during their entire expedition are tallied, 176 previously unknown species or subspecies can be listed, judging from a recent summary by the Sierra Club. At least 17 new plant species were discovered while the explorers were in the Great Plains region. Gary Moulton has summarized the specimen and archival data from all the herbarium sheets currently known to exist in volume 12 of his definitive 13-volume Journals of the Lewis and Clark Expedition. Names of the plants mentioned here follow this reference, sometimes with parenthetical synonyms of Latin or English vernacular names that have appeared in relevant literature, such as the books of Paul Cutright and Raymond Burroughs. The plants and animal species described in the text are arranged in alphabetic sequence using English names, and both the Latin and English names are those currently recognized as official. Alternate names given in quotes, including a few place names, are those used by Lewis and Clark, and their often innovative spelling has in such cases been retained.
In the course of the expedition the group lived off the land, killing and eating almost anything they could. Burroughs compiled a list of game killed in the course of the expedition, largely for human consumption. At minimum, it included 1,001 deer, 35 elk, 227 bison, 62 pronghorns, 113 beaver, 104 geese and brant, 48 shorebirds ("plovers"), 46 grouse, 45 ducks and coots, and 9 turkeys. They also killed 43 grizzly bears, 23 black bears, 18 wolves, and 16 otters. This level of resource exploitation marked the beginning of a century of unrestrained wildlife slaughter in America, ending in the elimination of the bison, elk, gray wolf, and grizzly bear from the Great Plains, and the complete extinction of the passenger pigeon, Carolina parakeet, and Eskimo curlew.
Exactly a century after the beginning of the Lewis and Clark expedition (1903), President Theodore Roosevelt established in Florida the first of our national wildlife refuges, and the long road toward the preservation and restoration of our wildlife resources was at last under way. There are now more than 530 national wildlife refuges in the United States, of which the Charles M. Russell National Wildlife Refuge in Montana is much the largest of those situated along the Lewis and Clark route. There are 20 national grasslands, totaling 4 million acres, 17 of which are in the western Great Plains from North Dakota and Montana to New Mexico and Texas. There are now also 155 national forests, covering almost 200 million acres, including the Lewis and Clark National Forest, located between the Missouri and Yellowstone Rivers of Montana. Also, there are 300 Indian reservations, now still home to members of about 500 tribes; ten of these reservations occur along the Missouri River between Nebraska and Montana, some of them supporting direct descendants of the people first encountered by Lewis and Clark.
I shall vanish and be no more,
But the land over which I now roam
Shall remain, and change not.
Anonymous Omaha Indian