The marshes also support wintering wildfowl and waders, including shelduck, wigeon, teal and curlew. These include ringed plover, little ringed plover, shelduck and oystercatchers. Three bird species occur in internationally important numbers&colon; common shelduck, pied avocet and black-tailed godwit. The ruddy shelduck is a mainly nocturnal bird. Feral ruddy shelduck have bred successfully in several European countries. This species is also known as the Korean crested shelduck, Korean sheldrake, and Korean Mandarin. The ruddy shelduck mostly inhabits inland water-bodies such as lakes, reservoirs and rivers. The crested shelduck was initially collected in April 1877 near Vladivostok, Russia. In 1991, the crested shelduck appeared on a Mongolian postage stamp. Old Chinese tapestries also portray a duck similar in appearance to the crested shelduck. Sometimes more than 1,500 ruddy shelduck are seen. Paradise shelduck are the most widely distributed waterfowl in New Zealand. However, the crested shelduck has not been definitively sighted since 1964. The ruddy shelduck grows to a length of and has a wingspan. The word "sheld" is a dialectal word meaning pied or multicoloured (as in shelduck).