Birding

In "Ride Natty Ride", Bob mentions Gwan. but I'm sure he does not mean this bird:

http://images.google.com/imgres?imgurl=http://www.bu.edu/scscb/images/trinidad-piping-guan-restall-painting.jpg&imgrefurl=http://www.bu.edu/scscb/working_groups/Actions/bird-april-08-trinidad-piping-guan.htm&usg=__bDe9tlKarO0eKcgqDAtboW2aakk=&h=367&w=265&sz=27&hl=en&start=2&sig2=2_PNr2gL4h8DTyEJSymYOw&tbnid=93o9kAmb1FQWJM:&tbnh=122&tbnw=88&prev=/images%3Fq%3DGuan%2Bbird%26gbv%3D2%26hl%3Den%26sa%3DX&ei=M97PSvDQBZjglQergI2pCg