As a kid spending summers on Little Sebago Lake in southern Maine, I was used to seeing snapping turtles. My brother, Tad, and I liked to hang out under the dock,—and we stared down the snapping turtles. Their trapezoidal heads poked up out of the water, nostrils flaring. When the snappers, or mud turtles, weren’t swimming in the lake, they hid in the marshy grove beside our camp. Neither my brother nor I were ever bitten by a snapper, but the possibility was there, under the dock—a thrill that propelled us a little faster through the water some days. Until this summer, I had not seen a snapping turtle at the lake since the early 1990s. One snapping turtle is back in our cove this summer, making a home near Fish Rock. We recognized its dark brown shell and distinctive-shaped head and hooked beak-like snout, used for capturing prey and self-defense, as it periodically inspected the surface, hiding beneath a mat of weedy reeds. Since the arrival of the snapper, the ducks and their babies have not made their usual pass through our cove.
So far, the snapper is alone, which makes sense since snapping turtles are not social creatures. She or he has made a home along a reef beside a peninsula that points to the Sand Bar, a favorite destination of boaters in the three-basin lake. Little Sebago is on the state’s top ten list for “most threatened by development,” and there has been a milfoil problem due to increased boat traffic after the town’s approval for a public boat launch. A number of local nonprofit organizations, such as Lakes Environmental Association and the Little Sebago Lake Association, have led projects to improve water quality and educational efforts about algae and wildlife habitat in the lakes region of southern Maine.
But common snapping turtles (Chelydra serpentina) are not unique to Maine; in fact, Maine falls within the northeast part of their range, including Nova Scotia. Snappers are found in the Gulf of Mexico—in Florida (along with a different species, the Florida snapping turtle) and the Texas coast, all along the Atlantic/east coast, and as far west as the Rocky Mountains. These turtles have been paddling in and out of North American wetlands for 80 million years. Adult snapping turtles prefer marshes, swamps, muddy still water, shallow lakes and ponds, while the hatchlings and juveniles live in small streams. Juveniles have small toothy ridges on their carapace called keels. When snapping turtles are young, they are easy prey for predators, including herons, bullfrogs, snakes, alligators and fish like bass or pike. Once a snapper is an adult, nothing messes with it, besides a human. The mobility of the turtle’s neck, which never fully retreats into its shell, allows it to reach out and snap—surprisingly fast.
Because they are poor swimmers, snappers do not like deep water, and can drown if they can’t reach the surface, or get to land easily. They need a combination of wetland habitat types to thrive, but can be found in both urban and rural areas. Oddly enough, they can gowithout water for a couple of weeks and even swim in the ocean while they are migrating from a stream or river to a pond or marsh. Large males are territorial and choose a fixed spot for their home but females tend to move around, possibly going back and forth between “homes” along the shoreline of lakes, ponds and marshes or swamps. For some amazing photos of snapping turtles in Virginia wetlands, visit:http://www.fcps.edu/islandcreekes/ecology/
common_snapping_turtle.htm
When wetland habitat dries up and there is less water, a snapping turtle will be forced to move to another location to live. Sometimes this involves crossing roads, which explains why we sometimes see a crushed turtle on the side of the road, and wonder, “why did the turtle cross the road?”
Despite their intimidating reputation, snappers are omnivorous, eating mostly aquatic vegetation. If ducklings are readily available, a snapping turtle might take one, but it’s incidental. Snappers may eat frogs and other amphibians, small mammals (like a mouse), mollusks and other invertebrates, and rarely—small birds. Snapping turtles may be poor swimmers but they are clever. When a wetland is matted with algae, snapping turtles use the cover to hide beneath and grab shorebirds by the feet. The turtles’ effect on game fish and shorebirds populations is minimal. For more information about their interactions with waterfowl, visit:http://www.tortoisetrust.org/articles/
snappers.htm
Next week, I will uncover the Legends of Snapping Turtles.
Further reading on blogs about common snapping turtles:
“Detroit Wildlife: Common Snapping Turtle” by Laura Sternberg, July 2011
http://detroit.about.com/b/2011/07/12/detroit-wildlife-common-snapping-turtle.htm
“Snapping Turtle Expresses Displeasure at Being Plucked from Pond” by Mark Frauenfelder, July 2011 http://www.boingboing.net/2011/07/12/man-grabs-angry-snap.html
“The Secret Life of Snapping Turtles” by John Marshall, January 2009
http://www.grit.com/Animals/The-Secret-Life-of-Snapping-Turtles.aspx
“The Snapping Turtle” by Ted Levin, Vermont Public Radio, October 2008:http://www.vpr.net/episode/44552/
To read Part 2: Legends of the Snapping Turtle, click here.
I just finished reading 
Whereas in a 2009 study of invasive apple snails, the gastropods are observed to feed on both native and invasive aquatic plants at the Great Lakes Center (Buffalo State College in New York). One of the findings was that apple snails should not be considered a bio-control in wetland restoration sites. While they ate the invasive aquatic plants, such asEichhomia crassipes, the snails also ate the native vegetation, e.g. Ruppia maritima, at an even faster rate. 
Strange Wetlands™ 