I spotted the raptors before I saw the Lake Jackson sinkhole. Osprey and Turkey Vultures wheeled in tight circles above a small pool of water, surrounding by the sloping sides of what had been the lake bottom. I walked to the edge, shielding my eyes against the bright summer sun to take in a Wood Stork probing the mud for prey, and nearly a dozen other vultures sitting on exposed earth, perhaps digesting bellies full of fish that hadn’t made it when a hole opened in the limestone shelf and drained the lake.
Now, the sinkhole and surrounding lake depression have become a birding hotspot.
Lake Jackson encompasses about 4,000 acres just north of Tallahassee. Though its deepest reaches extend down 25 feet, most of the lake is shallow, covered in a blanket of bright green lily pads. During extended dry periods, the aquifer below the limestone recedes, and the loss of equalizing pressure eventually leads to the opening of a sinkhole that carves deep valleys into the lake floor as water rushes to escape.
Florida in general is flat, flat, flat, so the jagged sinkhole ravines stunned me, like we had suddenly been transported to western mine country. Streams of remaining lake water continued to flow into the sinkhole, clear and warm. Yellow caution tape warned visitors not to get too close to the edge, though many had gone under or through to get a better look at the crevice below.
I visited again a few days later, and the small pool had disappeared. Fish skeletons littered the drying mud, and where once I had seen mostly raptors, I now spotted wading birds. White Ibis, Great Egret, Snowy Egret, Little Blue Heron, Tricolored Heron, and even Roseate Spoonbill searched for fish and other food between and under the remnant lily pads or in the pockets of water that remained. In the distance, an airboat carved a path through the vegetation, scattering dozens more egrets, herons, and ibises. I for one felt grateful for the avian clean-up crew; I had expected the whole area to reek of dead fish, but all I could smell was the earthy odor of the drying lake bottom.
To be sure, when the lake is full, you can see wading birds and other species, but right now there are many more waders in the area than normal.
Lake Jackson drains so regularly that its original name — Okeeheepkee — means “disappearing waters.” Nearby lakes also periodically drain, including Lake Iamonia, Lake Lafayette, and Lake Miccosukee. Lake Jackson drained in 1999 and 2006 (with extended low periods in between), as well as in 2012 and now 2021. As the region becomes dryer due to climate change, draining events could become more frequent.
Each sinkhole event opens a smorgasbord for birds and other scavengers. The resulting dry down is good for the ecosystem’s overall health, as the sudden onslaught of air speeds up decomposition of the bottom, keeping it from becoming too mucky and accumulating too much partially decomposed vegetation. The fish need hard bottom for their spawning depressions, and the birds in turn need a healthy fish population.
Eventually rain will recharge the aquifer, and once the sinkhole is plugged the lake will refill. Heavy storms should speed the process along, probably this summer. Until then, birders, geology enthusiasts, and interested locals and visitors alike will continue to flock to the site.