Gray Catbird agitated

A wet (having just had a bath) and very agitated Gray Catbird is scolding what is likely to be a snake somewhere below the bird. You can also hear its mate doing the same as well as a Willow Flycatcher and Song Sparrow. The background 'noise' is traffic along Rte 95 by the Philadelphia airport.
John Heinz NWR, Philadelphia
July 10, 2013