Secretary Birds (Sagittarius serpentarius) -- also known as "serpent eagles" - are highly skilled snake killers, which are part of their natural diet. They may use beak, wings and feet to kill a large snake; and they use their wings wings as shields to keep from being bitten. They can run so fast that they are sometimes referred to as "the devil's horse."
Relevant Bird Species Information Page (includes more stunning photos of this bird species)
Photographer: Martin Heigan http://www.flickr.com/people/martin_heigan/