[Journal entry for May 1, 2013; Owl Swamp, Harriman State Park, NY] In the late afternoon, I hike around Owl Swamp, in Harriman State Park. I am following up on an observation of open water in the swamp that Dallas and I made a few weeks ago when we observed it from the ridge atop Black Mountain. On previous trips we had not noticed any open water, so we suspect that beavers have constructed an impoundment there.

It’s fine and clear spring weather, with temperatures in the mid sixties, Fahrenheit. I park at the south end of the lot at the Anthony Wayne Recreation Area and take the Ski Trail south. Its trailhead is marked by an informational sign. This woods road parallels Beechy Bottom Brook. I crossed the brook and several of its tributaries, via wooden footbridges.

I connected with the Appalachian Trail (AT, blazed in white) and take it westward, crossing Beechy Bottom Brook again via another wooden footbridge. I then ascended up a terrace and cross the Palisades Interstate Parkway. I pass a Pussy Willow bush as I re-enter the woods. I then began to shallow ascent through generally rising country and connect with the 1779 Trail (blazed in blue), taking it south.

The trail follows the crest of a low ridge though open and pretty woods that is partly leafed out. The underbrush, which includes high and low bush Blueberry is more leafed out than the trees, but even the trees are visibly a lemon-green. I pass a very large sandstone glacial erratic boulder near the intersection of the 1779 Trail with Owl Lake Road. This road follows the western edge of Owl Swamp (which by implication was once a lake).

The swamp is actually much bigger than I had realized when Dallas and I viewed it from atop Black Mountain. Most of it is a Phragmites grass meadow, but a few sections have more varied vegetation and two are open water. I bushwhack along its edge and find several places where I can struggle past high bush Blueberry bushes and view open, marshy meadows of cattails, sphagnum moss and grass hummocks. I follow the western edge of the marsh southward, negotiating several pretty tributary streams, and eventually rejoin Owl Lake Road.

The road leads to the dam at the south end of the swamp and to a smallish patch of open water just north of the dam. The dam itself has been intentionally reduced in height, with cement-covered boulders originally part of its structure heaped up on its downhill side. Perhaps this is why it now impounds a swamp and no longer a lake. Beavers have dammed the sluiceway and built a lodge on the dam, but their work appears old and unmaintained.

I spot a snapping turtle, with a shell about a foot long, on the grass near the sluiceway and spend several minutes watching it. It sees me, makes a half-hearted attempt to withdraw its limbs into its fat body, looks unhappy but does not move. I then walk out onto the dam where I spot another snapping turtle, at least twice as large as the first, floating peacefully in the water. It sees me but seems unconcerned. I inadvertently disturb a large snake – a northern water snake, perhaps, though I do not get a good look. It dashes into the water and swims off.

The water is teeming with salamanders, tadpoles and fish. Amphibian egg masses are clinging to dead, submerged branches. They seem to be of two types, one a milky green color and the other clearer but with dark flecks that I suppose must be the fetuses.

I then bushwhack along the eastern edge of the swamp, on the flank of Big Bog Mountain. The going is pretty tough in places, for the vegetation is pretty dense. I eventually come to a point of land where I can view the second section of open water. This is the open water that Dallas and I saw from the ridge of Black Mountain, judging from my unobstructed view of the ridge from this vantage. As I suspected, the water is impounded by long, arcuate beaver dam on the south side of the pond. A lodge has been built on the west side of the pond. A large tree has been felled recently, its exposed wood sill yellow, confirming that the beavers are still in residence. Dallas and my inferences of beaver activity are correct, but the beaver pond is actually much smaller than we imagined. It just happens to be well-positioned to be seen from Black Mountain, whereas the much larger Phragmites meadow is mostly obscured by trees.

I finish bushwhacking around the swamp, rejoined Owl Lake Road and then taking that woods road eastward to where it terminates at a gate along the Palisades Interstate Parkway. I cross the Parkway but find the island between the northbound and southbound lanes difficult, owing to a patch of Poison Ivy that I cannot completely avoid. I then bushwhack west across the valley of the Beechy Bottom Brook, until I rejoined the Ski Trail, which I take back to my car.

About two and a half hours.