This photo was taken on October 22, 2011 in Arauca, Arauca, Colombia, using a Canon PowerShot S95.
About the bird species...
The Savanna Hawk (Buteogallus meridionalis) is a large raptor found in open savanna and swamp edges. It breeds from Panama and Trinidad south to Bolivia, Uruguay and central Argentina.
The call is a loud scream keeeeru.
The Savanna Hawk feeds on small mammals, lizards, snakes, crabs and large insects. It usually sits on an open high perch from which it swoops on its prey, but will also hunt on foot, and several birds may gather at grass fires.