Rancho Grande was located at a mountain pass in a branch of the Andes known as the Venezuelan Coastal Range, which was an important migration route for butterflies, and the station proved very lucrative in the study of insects. During his work at Rancho Grande, Beebe broke his leg in a fall from a ladder, and the forced immobility which resulted from having his leg in a cast presented him with a new opportunity for observing the area's wildlife. At his request, he and his chair were transported into the nearby jungle, and as he sat motionless the wild animals around him soon began to go about their business without noticing his presence. His immobility also presented him with the opportunity to spend hours at a time observing a pair of bat falcons through binoculars, documenting the behavior of their two chicks and every prey item fed to them by their parents. His observations documented several behaviors which were new to science, including the first documented example of play in birds.