Samuel Fuller didn't recognize this picture because it was re-edited by the producer. Fuller never wanted to talk about it.
The opening credits include the following printed statement: "This film is dedicated to the fearless stuntmen who repeatedly risked their lives against attacks in shark-infested waters during the filming of this picture..."
The original film's title was "Caine", after the main character's name (played by Burt Reynolds), but the producers decided to change the name so it would sound like a killer animal movie, in order to draw younger crowds.
This film gained some infamy at the time of its release because of the death of one of its stuntmen. He was attacked and killed on camera while working with what was supposed to be a sedated shark. When the production company used the death to help promote the film, director Samuel Fuller, who had been clashing with the producers on a wide variety of issues relating to the film, quit the production. When he finally saw the version that was released to theaters, he said they had butchered it so badly while editing it that it was no longer recognizable as his film and demanded that his name be taken off of it, but the producers refused.
While the plot is set in Sudan (North Africa), the movie was actually filmed in Mexico.