Habitat      Calamus Swamp, Pickaway County: A Columbus Audubon Preserve Calamus Swamp, located 1.5 miles west of Circleville, Ohio, was generously donated to Columbus Audubon by Percy May family members Ada May Burke and Sally V. May, who wish to see it preserved forever. Calamus Swamp is a beautiful, diverse and rare wetland that was dedicated as a Columbus Audubon Preserve on June 3, 2000. Calamus' 19 acres offer a unique glimpse into the glacial past that shaped Ohio's landscape. It is home to several distinct plant communities and numerous breeding birds, and is an appealing resting spot for birds migrating through the Scioto River corridor. Columbus Audubon is proud to provide stewardship for Calamus Swamp. We have built a boardwalk and blind enabling greater accessibility without compromising the sensitive habitat. Our management plan provides for its ongoing care, guided by the Conservation Committee (Dave Horn, chair, 614-262-0312, conservation@columbusaudubon.org). We offer field trips to Calamus throughout the year. Following is a summary of this rare habitat. For a more detailed article about the natural history of Calamus Swamp, click here. Natural History Calamus Swamp is the only naturally vegetated and undisturbed kettle lake known to survive in central Ohio today. Glacial kettle lakes are remnants of the Wisconsinan glacier that shaped Ohio's landscape some 12,000 years ago. They were formed when massive blocks of ice fell away from the thawing glacier and created depressions of varying sizes and shapes in the soft, wet earth. As the blocks melted, the kettle depressions filled with clear water, forming open lakes that dotted the Ohio landscape primarily in the west central, northeast and northwest regions of the state. Unfortunately, most have met a harsh fate. Over time, most have filled in with dead plant material and disappeared altogether, victims of the relentless process of ecological succession. The aquatic vegetation in Stage's Pond State Nature Preserve, another glacial kettle lake located in Pickaway County, has been almost completely destroyed by excessive sedimentation and fertilizer runoff from neighboring farms. That leaves Calamus Swamp as a most extraordinary relict of central Ohio's glacial past. Unique Plant Communities Swamp Forest Inhabitants:  Calamus Swamp is ringed with trees that require seasonally moist soils. American Elm, Green Ash and, in places, Red and Silver Maples make up the swamp forest here. Breeding birds attracted to this habitat include Great Crested Flycatcher, Red-bellied Woodpecker and Warbling Vireo. The uncommon and beautiful Prothonotary Warbler also nests here. Buttonbush, Cephalanthus occidentalis:  Buttonbush belongs to the same family as the plants that produce coffee. At Calamus Swamp, Buttonbush is the most characteristic shrub. It grows in deeper water than other shrubs and often forms dense colonies. When in bloom, Buttonbush is easily identified by the ball-like clusters of white flowers. Swamp Loosestrife, Decodon verticillatus:  Swamp Loosestrife forms dense tangles that grow in deeper water than the other plants at Calamus Swamp. It plays a critical role in the growth of plant life in an open-water environment. When the tips of the drooping Swamp Loosestrife branches touch the water, they form small pads of a special biological structure called "arenchymous tissue." The pads float atop the water and serve as hosts to other plants. Ultimately this process fills in the open water with burgeoning plant life. While it belongs to the same family, this valuable plant should not be confused with the non-native, invasive Purple Loosestrife. Bur-reed, Sparganium eurycarpum:  One of the mysteries of Calamus Swamp is how it got its name. Acorus "Calamus" is the scientific name of Sweet Flag, a common wetland plant related to the Jack-in-the-pulpit. The mystery comes in when you consider that Sweet Flag has never been documented at Calamus  and that the habitat is not right for Sweet Flag to grow. One likely explanation is that certain cattail-like plants occurring at Calamus were mistaken for Sweet Flag. These plants actually are Bur-reeds. They are unrelated to Sweet Flags, but their leaves are similar. Bur-reeds are important food plants for waterfowl and provide valuable nesting cover for birds like the Virginia Rail and Least Bittern. With its spiky balls of fruit, Bur-reed is sometimes called Mace-plant, after a metal-headed, spiked club of the same name that was used as a weapon during the Middle Ages. Submergent Aquatic Plants:  Hidden beneath the large expanses of open water are fascinating plants not easily seen by visitors to Calamus Swamp. The Bladderwort is one of the most unusual plants in this "submergent" zone. Bladderworts are miniature, free-floating carnivores. Instead of getting their nutrients through roots anchored in the ground, these hungry plants are free-floating and use "snap traps" to capture small animals. In summer, their tiny, bright yellow flowers are held above the water's surface and resemble violets. Other plants found in the deep water include Coontail, Duckweeds and one of the world's smallest flowering plants, Water-meal, which looks like tiny, green grains of sand. Water Birds With the Scioto River located just 1.5 miles east, Calamus Swamp is an appealing resting area for the many water birds that migrate through the Scioto corridor. In spring and fall, watch for ducks, geese, grebes, and the occasional loon or cormorant. Unusual nesters recorded for this region include American Coot, Pied-billed Grebe and Common Moorhen. Photo © Mike Flynn, 1999 Page updated 09/19/05 © Columbus Audubon 2005