Robert F. Kennedy Jr. is under investigation by the National Oceanic and Atmospheric Administration after a bizarre comment about beheading a dead whale that washed up on a beach, CNN reported. While speaking in Arizona on Saturday, Kennedy told a crowd that he got a letter from the National Marine Fisheries Services, which falls under NOAA. The letter, he said, revealed he was under investigation for the incident that occurred 20 years ago. “It is long-standing NOAA practice not to comment on open investigations,” a NOAA spokesperson said on Monday when CNN called to confirm. Want more breaki…