Amsterdam duck

Barely larger than a thrush

Both Amsterdam Island and Saint Paul are more than 3,000 kilometers away from continents. Nevertheless—or perhaps precisely because of this—the two islands were frequently visited by early seafarers and the animals that traveled with them, so that all endemic birds there had already been wiped out before they could be scientifically described. The same is true of the small, flightless Amsterdam duck, which was only described in 1996 on the basis of bone finds by the ornithologists Storrs Lovejoy Olson and Pierre Jouventin.

The Amsterdam wigeon was mentioned in writing much earlier: in 1696, William de Vlaming noted that he believed he had seen “two four-legged animals resembling a weasel or fox” in the reeds of Amsterdam Island. Zoologists W. R. P. Bourne, A. C. F. David and C. Jouanin interpret de Vlaming’s sighting in a 1983 article as an Amsterdam duck. They are certain that it cannot have been a mammal, since mammals are said to have reached the island only later via seafarers and whalers. The British ornithologist Julian P. Hume, however, does not rule out in Extinct Birds (2017) that de Vlaming may also have seen rats.

Another written mention comes from the British historian John Barrow; he reported in 1793 about a “small, brown duck” on the island of Saint Paul that was barely larger than a thrush. By way of comparison: the song thrush (Turdus philomelos), which is also native to Europe, reaches a body length of 20 to 22 centimeters.

The Amsterdam duck differed in its size and its reduced wings from all other known duck species. The only duck species similar to it is the larger, flightless Auckland teal (Anas aucklandica), a dabbling duck (Anatini) from the subantarctic Auckland Islands. The bill of the Amsterdam wigeon was very short and rounded at the tip, so it is most likely placed in the genus Mareca, which also includes the Eurasian wigeon (M. penelope).

The first bones of the Amsterdam duck were found as early as 1955 and 1956, which researchers described as similar to the bones of the garganey (Anas querquedula). In 1987, further bones from at least 30 individuals were found. These indicated a small duck with a short bill. The robust legs, reduced breastbones and wing bones suggested flightlessness.

The bones also showed that the Amsterdam duck drank little salt water, which is why the bird presumably did not live on the coast. The bones were recovered 500 meters above sea level.

Amsterdam duck – fact sheet

alternative names	Amsterdam Island duck, Amsterdam wigeon
scientific names	Anas marecula, Mareca marecula
original range	Amsterdam Island, probably also Saint Paul Island (Indian Ocean)
time of extinction	end of the 18th century
causes of extinction	overhunting, introduced animals on islands
IUCN status	extinct

Amsterdam duck: home island still unclear

It is still unclear whether the extinct Amsterdam wigeon was endemic only to Amsterdam Island or also occurred on Saint Paul Island. Since all bones of the Amsterdam duck were found on Amsterdam Island in the southern Indian Ocean, scientists today assume that this duck species was native there.

However, Barrow’s report comes from the neighboring island of Saint Paul, so it is not certain whether the duck described by Barrow was merely a similar species or whether the Amsterdam duck did indeed inhabit both islands.

The distance between the two islands is only 80 kilometers. Olson and Jouventin believe that birds that lived on one island could quite possibly also have lived on the other.

Bones only a few hundred years old

The International Union for Conservation of Nature (IUCN) dates the extinction of the Amsterdam wigeon to the end of the 18th century. In addition, the duck bones described by Olson and Jouventin are no older than a few hundred years.

In his report, Barrow provides a possible clue to the Amsterdam duck’s extinction. He wrote: The duck was the “preferred food source of the five seal hunters who lived on the island”.

Since the bones indicate that the dabbling duck could not fly, it would also have been easy prey for hunters. Animals living on islands in the absence of human civilization are usually not very shy (island tameness).

Although the Amsterdam and Saint Paul Islands are now, as then, largely uninhabited, Olson and Jouventin point to the islands’ strategically favorable position between Africa and Australia. They were therefore likely often visited by whalers and sailors. Presumably, these not only hunted the Amsterdam duck and possibly other endemic birds there, but also introduced foreign animal species and carried out land clearing by burning.