Newcomers to Colorado might not think of their new home state as a Garden of Eden. But a recent survey, States of the Union: Ranking America's Biodiversity, shows that Colorado hosts some 3,600 species, ranking 16th in the United States for the overall number of plant and animal species found in the state.
The study, commissioned by the Nature Conservancy, shows that Colorado ranks particularly high in the number of mammals (166 species or 6th in the nation), vascular plants (2,550 species or 7th in the nation) and birds (371 species, 7th in the nation).
And Colorado is notable for the presence of a large number (93) of endemic species, those found nowhere else in the world.
"The study offers a starting point for both research and discussion," said John Sovell, head zoologist for the Colorado Natural Heritage Program headquartered in Fort Collins. CNHP scientists conduct field studies for their parent organization NatureServe, sponsor of States of the Union, a nonprofit organization "dedicated to providing the scientific knowledge that forms the basis for effective conservation action."
"I think it's interesting to note that although Colorado is not at the top of any of those lists we are in the top half of all those lists, especially the number of endemic species," said Sovell.
In addition to ranking states for biodiversity and endemism (the number of species endemic to the state), States of the Union ranks the number of at-risk, near extinct and extinct species in each state.
Of the total number of plant and animal species found in Colorado, some 10 percent are considered rare or at risk of extinction -- 11.2 percent of vascular plants, 4.1 percent of reptiles and 18.8 percent of freshwater fish. Birds and mammals showed a relatively low number (1.9 percent) of at-risk species.
Some species are at risk simply because of their rarity -- there may be only one or two known colonies in the world. Others may be at risk because of human intervention -- land-use patterns, development in fragile areas, recreational usage or location of large water or energy projects in an area that harbors a rare species.
"The study is a starting point for communities to help make decisions that are at least informed," said Sovell. "The main thing is to recognize that there are a great number of species out there and many different types of habitat."
Chris Pague, a conservation biologist for the Nature Conservancy of Colorado, agrees.
"The biggest issue -- and this is why natural heritage programs were formed -- is letting people know the relative status of biodiversity in their area and where [they] might be most concerned or interested," said Pague. "Personally, I use that information to decide where to take my vacation. If one wants to see the most penstemon species [a high country wildflower], for instance, you'd want to go to Colorado or Utah."
"The study is useful for proactive, thoughtful planning about how we want to treat our natural heritage," he said.
Often that puts zoologists, botanists, average citizens and developers at odds, he explained, as was the case with the Preble's Jumping Mouse in El Paso County in the past decade. Had we known the rare mouse existed before development plans were made, says Pague, we may have avoided the controversy that eventually erupted over building in areas where the mouse was present.
"If you don't know it's there, well, some people would prefer it to remain that way," he said. "But others want to know, to be able to act proactively to protect the species."
Sometimes the conservation process casts a light on species that might seem unimportant. Eastern El Paso County, for example, hosts plains ragweed.
"It's a very mundane-looking plant," said Pague. "It even sounds awful. But it exists in ephemeral wetlands, playas, in only about three or four counties in the world, and El Paso County is one of them. If one is concerned that no species be destroyed, then the plains ragweed would be significant."
Sometimes a species is at risk of extinction simply because humans do not know it is there. As an example, Pague points to the Parachute and Rifle area of Colorado, where a rare penstemon species exists that was not discovered until the 1980s.
"There are only three populations in the world," said Pague, "and out there you find them on the edges of the big white cliffs. A mistake could take them out pretty quickly."
Working on a Deptartment of Energy project a few years back, Pague came across the rare penstemon and saw a group of parasailers running "right across the population to get their jump started."
In Colorado, says Pague, there are a large number of plant species that are "very, very local," some of them relatively near to Colorado Springs. These plants exist in the shale and limestone outcroppings along the Arkansas River, for example, between Pueblo and Canon City, where they are in danger of colliding with developments like Pueblo West. Rare plant species live in isolation, he explains, "like on islands." Those that are found on public lands have more of a cushion for protection, but those in the path of development are more at risk, in a place where they may "coincidentally come into conflict with human enterprise."
But both Pague and Sovell urge that the States of the Union study is a cause for celebration among Coloradans and a useful tool for future planning.
"It's funny," said Sovell, "the numbers the report listed are fewer than the number we've identified here at the Colorado Natural Heritage Program. What one author considers to be a distinct species, another may not. We had 1,000 more plants identified in our studies, just over 3,000 total in the state."
Chris Pague hopes that planners, government bodies, scientists, hobbyists, and urban and rural dwellers alike will see the study as a celebration of abundance.
"I hope it will get people excited and feeling comfortable that there's lots of neat stuff out there."