The National Geographic magazine that hit newsstands and mailboxes Tuesday features a story about Tennessee's Duck River -- hailing it as one of four of the most biodiverse places in the world.
In the magazine, the Duck joins the company of Table Mountain in South Africa, a cloud forest in Costa Rica and a Pacific Ocean coral reef in French Polynesia.
At those locations, National Geographic photographer David Liittschwager set out to capture as many local species in one cubic foot of space as he could.
What makes the Duck River special enough for such attention?
Time and geography, according to Leslie Colley, director of the Nature Conservancy's Duck River program.
"The glaciers never came this far south, so the creatures have lived there for eons," she said. "And it's largely unimpounded (by dams) so it has natural flows with the shallow shoals and (deeper) runs that mussels and many fish depend on.
"It's just a system that is ancient, and it's one of the last remnants of our great Southern rivers," Ms. Colley said.
In the Duck River, which begins on the Cumberland Plateau's western edge and flows 290 miles to the Tennessee River at the divide between East and West Tennessee, state and federal researchers have documented more than 150 fish species, as well as 55 freshwater mussel species and 22 aquatic snail species.
For National Geographic's February feature "Within One Cubic Foot," Mr. Liittschwager and biologists working with him managed to capture 32 fish species, seven mussel varieties and a number of small insects, snails, crayfish and turtles in the Duck.
"He came up with an incredibly creative way to take the abstraction out of the scientific word 'biodiversity,'" said National Geographic Senior Photo Editor Todd James. "He wanted to make it something you could hold in your lap."
Mr. Liittschwager again is on assignment for National Geographic and could not be reached for comment.
Mr. James said the photographer and his editors consulted with naturalists to choose four of the most biologically rich places in the world.
DUCK RIVER ATTRIBUTES
* 2 million acres -- drained by the river
* 290 -- miles of running river
* 151 -- species of fish
* 54 -- species of freshwater mussels
* 22 -- species of aquatic snails
Source: Nature Conservancy
What National Geographic found in a cubic foot
* 32 fish species
* 7 mussel species (3 endangered)
* several turtles
* 100-plus non-native Asian clams
To read the article, visit http://ngm.nationalgeographic.com/2010/02/cubic-foot/wilson-text
Source: National Geographic
"The freshwater river we picked in your backyard surprised me (in its richness)," he said.
Tennessee officials were not surprised, according to Tennessee Department of Environment and Conservation spokeswoman Tisha Calabrese-Benton.
"The Duck River is an incredibly valuable resource worthy of continued protection," she said. "We're glad to see it receive such esteemed recognition for its health and biodiversity."
She said state officials will continue to work for the river's protection with the several communities that use the Duck as drinking water for more than 250,000 Tennesseans.
Ms. Colley said the river does face threats, the same ones posed for every river. Those include changing land use, stormwater runoff from cities and farms along the banks, and agricultural churning that can carry mud and pesticides into the water.
She said she hopes the magazine story raises awareness of what Tennessee and the world have to lose.
"It confirms what we at the Nature Conservancy and biologists already knew: The Duck is a real treasure chest of species that are not thriving in other places, and some that are not even found in any other places," she said. "This shines a spotlight on that fact for people all over the country."