TrekEast Blog 15 Cahaba River

Shells and Shoals of Life

Snail and mollusk inventory

March 22, 2011

Had I another lifetime, I would study the phylum Mollusca.  I’d also try to figure out what fish each mussel depends on for dispersal.  More important, I’d try to help save them.

Just as Florida has the dubious distinction of leading the East in endangered ecosystems, Alabama leads in endangered species; and many of them are mollusks and fish of the Cahaba River.  While Florida (according to Reed Noss’s Endangered Ecosystems report) has several of the most imperiled ecosystems in the United States, Alabama has the greatest species diversity in several of the most imperiled taxonomic groups, and these include freshwater fish, mussels, snails, and crayfish.

To better understand Alabama’s riches at risk, after a couple days in Talladega National Forest’s Oakmulgee District (see last blog) and a rewarding evening with University of Alabama Environmental Council students, I was returned to the Cahaba River by Americorps VISTA conservationists Will James and Daniel Marbury. I joined a group of Alabama Rivers Alliance and Cahaba River Society and Nature Conservancy friends to paddle and dive in the river as it flew through Cahaba River National Wildlife Refuge (putting in at the wrongfully named Little Ugly Creek!) and beyond.  I was also joined on the river by Beth Young and Alex Varner, the same wonderful people who just days before had given me the tour of the Red Hills. I believe I saw, and learned about, more mollusk diversity in this eight miles of river than I’ve experienced before in my entire life.  Reach to the bottom of the Cahaba River behind one of its rock shoals and the handful of sand and gravel you pull up will have as many shells as pebbles.  The river fairly brims with fish and mussel and snail and diversity, ranking at the top of the world’s rivers for mollusks.

They would have all looked just like lovely shells to me, nameless and bewildering in their variety; but the day’s guides included aquatic biologists Randy Haddock of Cahaba River Society and Paul Freeman of The Nature Conservancy.  Both told me, if anyone says he can identify all these mussels and snails to the species level without a microscope, he is lying; but they both could identify, at least to the genus level, virtually every shell we found.  With only casual collecting, they spread out about 15 mussel and snail shells for display on a canoe bow, before tenderly placing each living creature back in the place from where they took it, gills upward.



The Cahaba is not a lazy brown river such as one might expect in the deep flat South.  Along the fall line, where the coastal plain meets the foothills, the river drops steeply over long stretches of shoals, and bluffs line parts of the river.  Just as the shoals create diverse habitats for a myriad of aquatic species, so do the bluffs provide many distinct niches for rare and endemic plants.  Indeed at a nearby Nature Conservancy preserve which we did not have time to visit this trip, Bibb County Glades, plant species new to science have been found and dozens of rare and endangered species depend on that natural opening in the forest. Part of the reason for the openness and the high numbers of rare plants is the keytona dolomite, a magnesium-rich limestone that creates a substrate favoring specialist plants.

The shoals also provide paddlers with opportunities for tips and turns.  One of the four canoes and the kayak nearly overturned, and their humbled paddlers had to go ashore to drain their boats. I was in the bow with veteran Cahaba paddler Randy Haddock at the stern, skillfully steering his canoe through the rocks and over the drops, so we stayed dry – when we weren’t diving for mussels.

Elizabeth Salter-Brooke, Katie Robertson Shaddix, and Mitch Reid of Alabama Rivers Alliance talked about threats to various Alabama rivers:  Agriculture and logging have diminished water quality in many places.  Dams have blocked diadromous fish and flooded the shoals that are the mussels’ and snails’ habitat.  Indeed, one of North America’s worst extinction episodes was when dams on the Coosa River flooded shoals and exterminated more than 30 mussel and snail species. Development is the fastest growing problem, as Birmingham booms.  As usual, lack of ecological awareness on the part of residents and visitors is an ongoing problem.  People simply do not realize that the fertilizer they apply to their lawn or the accelerated run-off from their driveway may be threatening the very existence of unique forms of life.

Unfortunately, some local people are also opposing an important effort to expand the Cahaba River National Wildlife Refuge.  As is often the case, opposition stems from misunderstandings about public land.  The fear of eminent domain (government taking private land) is misplaced here.  Conservationists, unlike developers, insist on willing-seller/willing-buyer arrangements.  In our out-of-balance economy, land seizures are often made for dams, roads, and the like; but extremely rarely for natural areas protection.

In a conversation the next day, my old friend, Ned Mudd – who, along with his partners in no-compromise conservation law, Ray Vaughan and Jasper Carlton, helped create the field of endangered species litigation – added urgency to the argument that development upstream is harming the Cahaba River and its wildlife.  Ned fears that despite years of hard work on the part of conservationists, we may see a biological meltdown on the Cahaba, largely due to urban and suburban sprawl up-river putting too much pollution, sediment, and run-off into the river.  Ned argues, and Alabama Rivers Alliance director Cindy Lowry and Black Warrior River-keeper Nelson Brooke seemed to agree, that if the Clean Water Act and other environmental laws were fully enforced, emissions from development upstream would have to be halted.

The visit to Cahaba River was followed by a visit to Big Canoe Creek.  There on the banks, Big Canoe Creek Association director Doug Morrison and his wife Joan kindly hosted several of us wild lands and waters folks.  Doug is a great example of why there is such hope in Alabama waterways.  Doug is a long-time native of Alabama, an avid hunter and paddler, and a tireless advocate for the wild waters and lands he loves.   Good folks like Doug & Joan and Alex Varner and Nelson Brooke (both of whom were also with us that evening on Big Canoe Creek) are striving mightily to protect and restore Alabama’s creeks and rivers and the lands alongside. 

Less than 5% of Alabama’s land is protected at this point – much too little to preserve Alabama’s great natural heritage.  With reauthorization of the state’s Forever Wild land acquisition program, however, and the ongoing work of Alabama Rivers Alliance and associated watershed groups, Wild South and similarly strong advocacy groups, and Nature Conservancy and other land trusts, whole ecosystems can be restored, working outward from the state’s arteries (streams) and organs (intact forests).  (Please see Brian Trzaskos’s writings on ecosystem/human body health parallels at  So did we end the evening by Big Canoe Creek, vowing to cooperate to connect wild Nature throughout Alabama beginning with the waterways and native forests and expanding far outward.  Waterways to wildways – that’s another part of the larger Eastern Wildway vision that will keep all of us working together for many decades.

For the Wild,



Mussel: Smithsonian Institute

Cahaba Lilly:  Beth Maynor Young

Bottom right: bluegill in the Cahaba 



If bivalves had big eyes or soft fur or feathers, half of them would not be trending toward extinction.

This is fascinating. Are there good places one can snorkel or scuba?

Probably some good snorkeling in the Cahaba River, but not really deep enough for scuba. Cahaba River Society, Alabama Rivers Alliance, and Nature Conservancy are the experts. I think they'll urge great caution, so as not to disturb any beds of rare mussels. On our paddle down the river, we enjoyed just wading carefully and dunking under to look at the mussels.

Thanks much

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