What Happens to a Feather When It Is Dipped in Oil & Water?

Feathers keep birds insulated, waterproof and buoyant when they are aligned properly and kept clean and dry by the bird. Their feathers have a small amount of natural oil on them, but if a bird dips its wings in oil-ridden water --- from an oil spill, for instance --- or dives for food in the water, they have a hard time removing the oil. Excessive amounts of water and oil endanger feather health and the bird's health.

  1. Loss of Waterproofing

    • Oil makes feathers separate from each other.

      When a bird's feathers are covered in oil, they stick together and separate. For waterbirds, this means their feathers no longer waterproof and insulate their bodies, exposing their skin to extreme temperatures. If the oil cannot be shed or cleaned off, birds can die of hypothermia or hyperthermia because they cannot control their body temperatures.

    Feathers Lacking Natural Oil

    • Feathers that do not have enough natural oil on them due to muddy conditions or dysfunctional preening glands absorb water instead of repelling it. Birds with problem feathers try to return their feathers to normal by continuing to preen, but they end up causing more damage to the barbs. Sometimes this results in the feathers breaking off; at other times, if the feathers are new enough, they will grow out.

    Overpreening by Birds

    • When birds are coated in excessive amounts of oil, they try to clean their feathers off by preening, or biting, at their own feathers. The extreme amount of preening can break down the barbs that help feathers hook together for insulation and waterproofing. This damages the structure that makes feathers effective.

    Damaged Shaft and Vanes

    • The shaft is what attaches the feather to the bird's body.

      Feathers are made of keratin, the same material that forms the main constituent of hair, fingernails, claws and beaks. Because of keratin's soft nature, feathers are fragile and can be easily damaged. The shaft of a feather is the main tubular centerpiece that all the vanes, or softer "feathers," extend from. Exposure to excessive oil, water and preening by the bird or washing by rescue workers can damage the shaft and vanes of feathers beyond repair.