Chasing fish in Alabama can be a life-changing event.
Last March, the Cahaba River Society (CRS) took the Emerge Sustainability leadership class from the Green Resource Center for Alabama out on the Little Cahaba River . The group, consisting of 15 to 20 professionals from Birmingham, preceded to “seine” for fish and other critters. To their astonishment, after “chasing” fish in a ten yard area, they were able to identify 8 different species of darters. That’s 10 yards. The distance of a first down in football.
Seeing and touching eight different kind of darters in one small place is unforgettable.
Mike Howell, a retired professor in biology at Samford University best described the experience.
“I never get tired of taking a group of students out, hearing the students exclaim about the beauty of the fish. They get so excited, it re-excites me. It’s a form of discovery, each time you go out, you don’t know what’s going to come up in your net. And you know in Alabama, its going to be something you are not expecting and that is what blows you away.”
“You become entranced by the beauty of the darters. They each seem like they have their own magical colors of the rainbow. The colors just capture you. Once you are captured by something like that, it sticks with you.”
Alabama’s aquatic biodiversity has no equal in North America. The state ranks first in the nation in number of different kinds of freshwater fishes, mussels, snails, crayfish and turtles.
According to Pat O’Neil, from the Geological Survey of Alabama, the reasons for Alabama’s aquatic biodiversity boil down to four items: climate, geology, time and habitat diversity. They are all interlinked.
“Alabama has quite a diverse geologic footprint. We have the coastal plain sediments that range in age from one year to 60 million years. In the Piedmont, we have the very old core of the Appalachian Mountains, that were once thought to be as tall as the Himilayas. And through time, those mountains have eroded and sediments are what we see that flow into the coastal plain and the Gulf of Mexico.
There is the valley and ridge where those mountains were crumpled together through time, several layers of rock have been eroded and exposed. Then there is the Highland rim in the northern part of the state. All of those different and unique geologic areas in the state, when you combine them with the availability of water, it results in this phenomenal array of aquatic habitats from lakes to springs and bogs, cave environments, small streams and large rivers, salt water marshes – all of these work together for a revolution to take place.”
The number of independent river basins is the key factor that creates the fish diversity that also drives the mollusks, snails, turtles and crayfish diversity. Alabama’s ten separate watersheds is the first link in that diversity chain.
How significant is Alabama’s aquatic diversity? Take for example mussels. Today, scientists have identified 182 species of freshwater mussels in Alabama alone. There are nearly 800 species globally. That works out to almost a quarter of the freshwater mussels on earth occurring in Alabama.
And it is not just fish, mussels and snails. According to Mark Bailey, conservation biologist and co-author of the book Turtles of Alabama, the Yellowhammer State has 40 turtle species that occur in Alabama, more than any other state. Five are sea turtles and three are terrestrial, so the remaining 32 are aquatic species that live in freshwater or brackish habitats. There are also 32 native frog species in Alabama which is more than any other state except Texas.
Bailey also credits Alabama’s aquatic species richness to a combination of geographic diversity and the presence of numerous river systems.
Why does Alabama aquatic biodiversity matter?
When scientists consider this question they provide numerous reasons why people should care about aquatic biodiversity. For example, Paul Johnson, Program Supervisor at the Alabama Aquatic Biodiversity Center recognized its global significance and connection to clean water.
“Alabama ‘s aquatic diversity is a miracle of natural history globally. Africa has antelopes and lions. Lots of monkeys in South America. Each region on the planet have unique fauna with it. In the Southeast, in particular Alabama, that fauna is aquatic. This is without question the largest conservation crisis in North America, but nobody knows about it because 95% of the animals fit in a shoebox.
The second reason – when people talk about critical infrastructure they talk about pipelines, highways, bridges,and electrical grids. Nobody ever talks about rivers. I haven’t checked recently, but I’m pretty sure not many of us can get too far along without sufficient tap water. “
Mark Bailey warns about the great unknown. If we lose our aquatic species in Alabama; which “link” could collapse the entire system?
“Different people care about preserving wildlife for different reasons. Some sadly seem not to care at all. I believe we have an ethical responsibility to not be responsible for the disappearance of other species, and the incredible diversity of life, to invoke Louis Armstrong, makes me “think to myself, what a wonderful world.”
But there are more practical reasons to care as well. Because of man-induced environmental changes like air and water pollution, forest clearing, and loss of wetlands, extinctions are occurring at a rate that far exceeds the natural speciation rate, and this diminishes the diversity of life. We don’t know how many species we can lose before whole ecosystems begin to fall apart.”
Pat O’Neil with the Geological Survey of Alabama sees the aquatic biodiversity as our state’s early warning system to prevent water pollution problems.
“Living in a state with incredible biodiversity is a treat.The critters themselves, all aquatic groups, turtles, salamanders, snails, mussels, fishes and aquatic invertebrates they all like the canary in the coal mine analogy. They are an in-stream full time 24/7 365 day monitoring tool that is out there in the wild. The critters tell us what they see are the problems.”
Mike Howell, the scientist who discovered the endangered watercress darter nearly 50 years ago and taught at Samford University for four decades says Alabama’s aquatic biodiversity matters because it changes lives.
“Many people have yet to experience the beauty and the diversity of these fishes because most people have never really put their feet into a stream. How many people walking up and down the sidewalks of Birmingham, Alabama have ever been out in a creek or a shallow river like the Cahaba River with a big long fish net kicking the rocks and when the net is pulled up, they see something gorgeous. The blue, reds and yellows of darters and minnows. It’s a discovery.”
Unbeknownst to many of us, Alabama’s abundant aquatic biodiversity does matter. It is a global natural wonder. It ensures us clean water. It holds our ecosystems together. It is an early warning system. And perhaps most importantly it provides us beauty, colors, enriched lives and discovery.
About this series
This is the second of three installments on our series about Alabama’s biodiversity. The first feature examined why Alabama ranks first in biodiversity nationally. The third subject will delve into Alabama’s tree and plant diversity. Thanks for following.