New Jersey’s open occurrence databases hold 898 beaver records, more than any other mammal on this list. That count reflects how easy a gnawed stump or a flooded trail is to spot, not a headcount of the animals themselves.
Dammed water from the Highlands to the Pine Barrens
A beaver needs slow, permanent water and woody plants close to the bank, and New Jersey offers two very different versions of that setup. In the Highlands, records cluster around the reservoir-fed streams near Wawayanda State Park and along the Kittatinny Ridge corridor by the Delaware Water Gap, where rocky, cold-running creeks back up into beaver ponds. Farther south, the tannin-stained blackwater rivers and cedar swamps of the Pine Barrens around Brendan T. Byrne State Forest give beavers a sandy-bottomed version of the same slow water to work with.
A vegetarian that floods its own neighborhood
Despite sharing its pond with fish, a beaver eats none of them. It lives on bark, twigs, and the soft cambium beneath, plus whatever aquatic plants grow nearby, and by fall a colony wedges a pile of cut branches into the mud near the lodge to reach through winter ice. That habit is why a dammed stretch of Pine Barrens swamp or Highlands stream slowly widens into open wetland. The dam changes the site as much as the beaver uses it.
Records track the spring thaw
Reports climb through spring, peaking from March into May, which lines up with the season when ice pulls back from ponds and two-year-old beavers leave home to found colonies of their own, leaving fresh dams and pale, chisel-marked stumps that are hard for a hiker to miss.
Status in New Jersey
NatureServe ranks the beaver S5, secure, and it’s native to New Jersey.
Full species profile
