Why does feathers absorb oil?

It is a interesting (sad also) mechanism. Most sea birds have water proof feathers protecting them from the elements. But according to the link, oil mats together the feathers and water can seep in between the oil. Birds make matter worse, when through their preening (feather cleaning) they ingest the oil.

There are many links available on the internet that review the processes by which oil spills harm birds.

See related links.