Fiber Optic Cables: Understanding the Weak Points

Rodents, birds, and even insects can cause surprising damage to fiber optic infrastructure. While manufacturers account for environmental durability, pest-related damage is a different challenge altogether. Chewing, pecking, and nesting activities can compromise cable integrity, leading to signal loss or costly repairs. Keep reading to discover some of the components of fiber optic cables that are most vulnerable:

Outer Jacket or Sheath

The outer jacket is the first line of defense, designed to absorb wear and tear. It protects the delicate internal fibers by taking on environmental damage—scratches, bites, and tears—from animals. Rodents often chew through it, and birds may scratch it up as they perch or peck. Some pests even use the cables as walkways or look for nearby nesting spots, increasing wear on this layer.

Strength Members

Just beneath the outer jacket lies the strength member, usually made of aramid or Kevlar yarn. It reinforces the cable’s structure, but once pests get past the outer layer, they can dig into this layer too. Gaps or weak spots in the yarn give rodents and birds a path to tunnel deeper into the cable.

Buffer Tube

The buffer tube surrounds the fiber strands and provides protection from physical stress, moisture, extreme temperatures, and bending. However, if the cable runs near potential nesting sites or shelter, animals may scratch or gnaw through the outer layers—eventually reaching and damaging the buffer tube. Once compromised, the inner fibers are exposed to environmental threats that reduce performance.

Fiber Optic Strands

These fine glass strands carry the signal via light transmission. They're incredibly sensitive, and even slight damage—like scratching, bending, or biting—can degrade or completely interrupt the signal. Sometimes the effect is gradual, with signal quality slowly declining. Other times, a sudden surge in pest activity can lead to complete failure.

Cable Attachments and Hardware

Cables are supported by mounting hardware—brackets, straps, and clips—especially when installed on poles or buildings. These components aren’t immune to pest interference. Squirrels, rats, and birds can bend or loosen them, while nesting materials may corrode or clog up the parts. Damage to the attachments can strain the cable, increasing the risk of disconnection or fraying.

The best way to protect your fiber optic cables is to stop damage from the start. Reach out today to learn more about how Critter Guard's solutions can keep pests off fiber optic lines and utility poles.