Oil destroys the insulating ability of fur-bearing mammals, such as sea otters, and the water-repelling abilities of a bird's feathers, thus exposing these creatures to the harsh elements. Without the ability to repel water and insulate from the cold water, birds and mammals will die from hypothermia.

Many birds and animals also ingest oil when they try to clean themselves, which can poison them.

Fish and shellfish may not be exposed immediately, but can come into contact with oil if it is in the water column. When exposed to oil, adult fish may experience reduced growth, enlarged livers, changes in heart and respiration rates, fin erosion, and reproduction impairment. Oil also has effects on eggs and larval survival. For more information:
Office of Response and Restoration
Oil Spill Response (Diving Deeper podcast, 4.7.10)
Spill of National Significance - Preparing for Oil Spill Disasters
Oil in the Ocean
Explore: Oil and Chemical Spills
Oil Spills: Learn More
Effects of Oil Spills on Wildlife and Habitat (pdf),U.S. Fish and Wildlife Service Alaska Region

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