Director of Freshwater Conservation, The Nature Conservancy in Florida
Conservation often thinks big—because animals do.
Think about Africa’s Serengeti, where wildebeest annually migrate between two countries. Or the grizzly bears and lynx of the Northern Rockies, roaming hundreds of square miles in a season. Or Pacific salmon and their 900-mile journey from ocean to spawning river.
It’s often conservation’s job to link these animals’ far-flung habitats so they can migrate, forage and spawn. That linking up is what conservation biologists call “connectivity.”
But what about connecting small places like this tiny Florida stream I’m standing before? It’s anything but enormous – often, I can cross it in a casual step.
There are no grizzlies or salmon here. How could this connect anything worth saving?
Then I look at Steve Herrington, a fisheries biologist and director of freshwater conservation for The Nature Conservancy in Florida, who’s looking into the stream with the enthusiasm of a kid about to pounce on a frog.
He sifts through his net, calling out names of the fish as he placed them in a bucket.
“Black madtom! You would have never found one of these here before we removed the dam,” he says. “Here’s an interesting one. A spotted sunfish.”
None of which would be here, he adds, had this stream not been reconnected.
We were at the Conservancy’s Apalachicola Bluffs and Ravines Preserve, located in the Florida Panhandle. When the Conservancy purchased the preserve, this stream was blocked by an earthen dam constructed for recreation by the previous owner.
Sampling the water above the earthen dam, Herrington found that many fish species found in the lower parts of the stream had disappeared.
“We often talk about connectivity of large rivers, but this stream has important ecological functions as well,” Herrington says. “The fish and aquatic insects move up and down the stream. With the impoundment, they weren’t able to do so.”
Two years ago, contractors removed the dam and restored habitat along the stream. The question was: Would fish from the lower parts of the waterway move upstream into the new habitat?
That is the focus of Herrington’s latest research, about which he’s finishing a paper. The initial results are promising. “Before we removed the dam, many downstream species could not be found above the dam,” Herrington says. “On top of that, I only collected one fish above the unpaved road north of the dam.”
As we electrofished the stream, we easily caught a couple of dozen of native fish in a few minutes. They were clearly moving freely in the stream.
The diversity was astounding: Despite its tiny size, the stream contained more species than much larger (and more famous) Rocky Mountain trout streams. We looked at colorful minnows and brightly patterned sunfish, toothy pike and endemic salamanders.
And the stream could at times hold even larger surprises. It connected to the much larger Apalachicola River, full of large fish and other river creatures.
“I’ve seen alligator snapping turtles swimming up here,” Herrington says. “The only migratory fish in the Apalachicola that would use such a small stream is the American eel. After we removed the dam, we found eels upstream of the old dam within months.”
Certainly large lands and river systems are important. But sometimes conservationists fall into the trap of believing that only large systems are important for connections, for diversity. Sometimes, though, even a small creek can restore ecological function and amazing aquatic diversity, for a tiny fraction of the cost of a larger project.
“When you examine this stream, it’s a really amazing place, with such beautiful fish and even endemic species,” says Herrington. “The big rivers are important, but these little streams have tremendous value for conservation, too.”June 13, 2012
Matt Miller is senior science writer for The Nature Conservancy. Read his regular blogs at Cool Green Science.