Other fish in the estuary include Cod, Whiting, Dab, Plaice and Flounder. They feed in shallow littoral waters on herring, flounder, hake, anchovy, codfish, and sculpin. It is also used as fishing bait for fish such as flounder and sea bream. However, the groundfish, especially haddock, yellowtail flounder, and cod, have been overfished. Species caught include Black Fish, Porgy, Striped Bass, Black Sea Bass, Fluke, and Flounder. The Atlantic halibut is a right-eyed flounder. Popular saltwater game fish include red drum, spotted seatrout, flounder, and tarpon. The principal catches by value are clams, lobsters, squid, and flounder. They are an important food source for herring, cod, flounder, and striped bass. California herons were found to live mostly on sculpin, bass, perch, flounder, and top smelt. Mysids form an important part of the diet of such fish as shad and flounder. Commonly harvested wildlife include freshwater suckers, saltwater flounder, and small game, such as frogs. Also common are polar smelt, saffron cod, polar cod, flounder and Arctic char. Commercial methods for summer flounder typically include trawling. A flounder boat is specifically designed for gigging flounder.