A Chinese goose: the domesticated form of the Swan goose Anser cygnoides (that’s right, more than one species of goose has been domesticated: this was always assumed based on morphological features, but was confirmed genetically in a 2006 study [abstract here]). The Swan goose is also the ancestor of the domesticated African goose. Wild swan geese are native to eastern Russia, China and Korea (they used to occur on Japan, but haven’t been recorded there since the 1970s, except as rare winter visitors) and have declined severely since the 1950s due to loss of floodplain habitat and human hunting. All domestic forms of the Swan goose have a particularly big bill knob compared to the wild forms, and it is bigger in males than females. This individual is a male. The twists, turns and blind alleys of the Swan goose vagina were studied in the highly-acclaimed recent paper by Brennan et al. (2007), available free here: I would have blogged about it, but I was busy with turtle genitals at the time.