Sheriff Bluffer Duck was a male anthropomorphic duck.
Bluffer Duck was Donald Duck's great-grandfather, and as much a mix of bravery and ego as Donald himself. He had his initials "B.D." engraved on all his belongings, such as his golden cufflinks. The sheriff of a small Wild West town, he rose to fame when he appeared to single-handedly save it from a gang of masked raiders during a shootout in nearby Carbine Canyon, for which act he was recorded in The History of the Wild West and the town renamed in his honor, becoming known as Duck's Bluff.
In truth, however, Bluffer had achieved his victory not through marksmanship but through cleverness; disguised as one of the Masked Raiders, he sneaked into their camp and then threw a fistful of bullets into their campfire, making them believe that they were under attack from a much greater force than they actually were. At any rate, Bluffer then retired and got married. One of his children, Humperdink, became a farmer and the husband of Elvira Coot.
Some time around 1942, Donald Duck was met with the ghost of his buffalo-hunting "grandpappy", Grandpa Duck. Though Grandpa Duck is a name most commonly associated with Humperdink Duck, when Daisy Duck created an outdoors family tree by hanging Duck family portraits on a literal "tree", the portrait of Grandpa Humperdink was distinct from that of the Grandpa whose ghost Donald had encountered, who was instead labelled “Donald's great-grandfather”. This would suggest that this Grandpa Duck was in fact Bluffer.
Behind the scenes
Bluffer Duck is mentioned in the 1959 story Duck's Bluff Story.