The Collaborative International Dictionary of English v.0.48:

Sauger \Sau"ger\, n. (Zool.)
   An American fresh-water food fish (Stizostedion Canadense);
   -- called also gray pike, blue pike, hornfish, land
   pike, sand pike, pickering, and pickerel.
   [1913 Webster] Saugh

WordNet (r) 3.0 (2006):

blue pike
    n 1: variety inhabiting the Great Lakes [syn: blue pike, blue
         pickerel, blue pikeperch, blue walleye, Strizostedion
         vitreum glaucum]