On 1 July, 2011 a pipeline broke as a result of flooding on the Yellowstone River spilling at least 1,509 barrels of oil.
Initial response by International Bird Rescue was hampered by the flooding, which restricted access to many areas along the river. A number of lightly oiled nesting bald eagles were not taken in for cleaning as they had young on the nest. These birds were monitored. The chicks fledged and the adults remained healthy.
The majority of the 131 animals cared for during the spill were toads, snakes, and frogs. These species only required light washing before being returned to the wild.