The dikes were built to enable cranberry farmers to control water levels. The maxmum depth of Swan Pond is about 4 feet. Most likely, these ponds result from secondary ice that melted, allowing the ground above them to collapse. The Calverton Ponds are the site of the highest concentration of rare, threatened and endangered species of plants and animals in New York State. Thread-leaved sundew, pitcher plants, and bladderworts are insectivorous and occur at coastal plain ponds.
Insects stick to the hairs on the leaves of the sundews and are then digested by the plant.
The insects supplement the plants' diet with nitrates. The Peconic headwaters, as are the remainder of the Pine Barrens, are low in nitrates and other nutrients. Near Jones Pond, the Peconic is jagged and angular. Nearby, there are perfectly round ponds. Sears and Bellows Ponds are flat-bottomed.