The common residential fence is often an ineffective deterrent against the determined raccoon. These opportunistic omnivores view a fence not as a barrier, but as a minor obstacle to accessing food, such as garbage cans or pet food, or secure shelter like attic spaces. Their impressive physical adaptations mean that standard vertical structures offer little resistance to their movements. Understanding the raccoon’s physiology and exploiting the weaknesses in typical fence construction are the first steps in creating a secure perimeter.
Anatomy of an Expert Climber
The raccoon’s climbing proficiency is rooted in specific physical traits that grant them exceptional agility. Their front paws possess five non-retractable toes that function much like human hands, allowing for dexterity and a strong, grasping grip on irregular surfaces. This enables them to manipulate objects, open containers, and securely hold onto fence slats.
The ability of their hind feet to rotate 180 degrees is a significant adaptation. This anatomical feature allows the raccoon to descend a structure head-first, a feat few mammals can accomplish. When climbing down, the hind feet rotate backward, positioning the claws to hook securely into the surface, maintaining control during descent.
Common Fence Design Weaknesses
Many typical residential fence designs inadvertently provide the perfect structure for a raccoon’s climbing technique. Wood privacy fences, for example, feature horizontal support beams or backing rails on the interior side. These structural elements create a natural, built-in ladder, offering the raccoon stable, horizontal rungs to ascend easily. The gaps between the vertical pickets also provide ample purchase for their paws.
Chain link fences present an equally manageable challenge. The woven, diamond-shaped pattern of the wire mesh offers countless secure grip points for their claws and toes. Every intersection of the wire acts as a tiny foothold, allowing the raccoon to scale the fence with minimal effort.
Structurally Modifying Fences for Prevention
Effective raccoon prevention requires modifying the fence structure to remove all viable climbing purchase points. A primary strategy involves installing a free-spinning barrier along the top edge of the fence, often called a fence roller or coyote roller. These devices consist of cylindrical tubes, made of aluminum or PVC piping, mounted on brackets that allow them to rotate freely.
When a raccoon attempts to grasp the top rail to pull itself over, the roller spins under its weight, denying the animal the necessary grip and momentum to complete the ascent. A simple DIY version involves threading large-diameter PVC pipe over a tautly strung metal conduit or heavy wire. The spinning mechanism must be installed so the animal cannot reach a stationary part of the fence once it encounters the roller.
To counter climbing and digging, a structural modification known as an L-footer or barrier apron is highly effective. This involves attaching a section of wire mesh, typically 1×1 inch galvanized hardware cloth or 2×3 inch mesh, to the bottom of the fence and extending it outward onto the ground. The wire is then bent at a 90-degree angle to create an “L” shape, extending horizontally for at least 12 to 18 inches.
For effectiveness, the vertical section of the L-footer should be buried approximately 12 inches deep, with the horizontal section extending outward on the surface or slightly buried. This horizontal mesh prevents a raccoon from tunneling directly against the fence line, as attempted digging is immediately met with an impassable barrier. Addressing both the top climbing and the bottom digging threat is the most reliable method for fortifying a perimeter.