Extinct duck species

Geese and ducks are almost one of the most familiar birds with which humans have the closest relationship. Because of their large size, species such as mallards, grey geese, and swan geese were domesticated by humans a long time ago and became poultry such as ducks and geese. However, although humans have domesticated some geese and ducks, they have not saved other species from being hunted or extinct. Since humans have accurate records, 25 species of Anseriformes have disappeared from the earth forever (Julian P Hume & Errol Fuller, 2017). Let's take a closer look at several extinct ducks.

Auckland Island Merganser Mergus australis

The Auckland Merganser, also known as the Yellow-billed Merganser, belongs to the same genus as the Common Merganser and is most closely related to the Chinese Merganser. As early as the Roman period, Pliny used the word Mergus to describe diving birds, which then developed into the genus name of the merganser and the English word Merganser (anser means goose).

Like the common merganser, the Auckland Merganser also has a beak full of "sharp teeth" and lives by diving. However, the plumage of males and females is similar, both are mainly brown and black, but the male is larger and has more obvious crests. They are the smallest in the genus, reflecting the characteristics of island species, but have the longest beak. The short wings and tail do not affect their ability to fly. Some materials mention that they are flightless birds, which may be due to the misidentification or recording errors of the Auckland Island Duck, which also lives in the Auckland Islands. There are only five first-hand observations of this duck. Taken together, we can roughly guess their life: paired adults mostly move in streams or freshwater lakes on the island, while unpaired adults and juveniles may be forced to go to bays and estuaries to forage, but they will not venture to the open sea to hunt. Compared with the common merganser, their diet may also be more diverse. Crustaceans may be their staple food, but fish are also on their menu. Aquatic worms and mollusks have also been found in their stomachs.

When people think of Auckland, the first thing that comes to mind is New Zealand's largest city. However, the Auckland Merganser has nothing to do with this place. Instead, it was found in the Auckland Islands. This is a series of uninhabited islands located in the southwest of New Zealand, nearly 500 kilometers away from the nearest human settlement. It was not known until 1806. In 1839, two French warships came here. Charles Jacquinot hunted a merganser and published it as a new species in 1841 together with the ship's doctor Jacques Hombron. This is the Auckland Merganser, and its specific epithet australis refers to the imaginary southern continent. Perhaps due to the remoteness and harsh climate of the Auckland Islands, not many people went here. It was not until 1847 that someone collected the second specimen. In the following 60 years, people collected a total of 23 skin specimens, 3 skeleton specimens, 3 chick specimens, and an individual soaked in alcohol. The last pair of Auckland Mergansers were shot at Canary Wharf by the then Governor-General of New Zealand, the Earl of Ranfurly, on January 9, 1902. Their skeletal specimens are currently stored in the British Museum.

Obviously, when people discovered the Auckland Merganser, their numbers were already small, and it is estimated that their breeding population did not exceed 30 pairs. This may be due to the small area of ​​the Auckland Islands, which limited the breeding environment and ideal foraging areas, limiting their population growth. However, on the South Island, the largest island of New Zealand, people have found their sub-fossil specimens, and their bones have been found in the "kitchen waste" of Polynesians, indicating that they once lived freely on the South Island. There are also traces of them on the North Island, Stuart Island and even Chatham Island. However, since Homo sapiens landed and settled on this land in the 13th century, their situation has been like their neighbor, the Elephant Bird, and they quickly went extinct. The Auckland Islands became their refuge-until the islands were discovered.

In 1807, pigs arrived on the Auckland Islands, and in 1820, cats arrived here, which may have led to the rapid decline of the Auckland Merganser population on the islands. In 1846, the British Charles Enderby led a group of Maori to the Auckland Islands, trying to develop agriculture and whaling. In 1850, they moved to the present Ross Harbor, but because the natural conditions of the Auckland Islands were not suitable for human settlement, Enderby's attempt failed in 1851. When the settlers were trapped on the island with a shortage of food, it was difficult not to think about the mergansers in front of them, which opened the final chapter of the extinction of the Auckland Merganser.

The specimen collection boom in the 19th century dealt the final blow to the Auckland Merganser. Earl Ranfurley searched for this rare merganser in every bay of the Auckland Islands and provided nine specimens to the British Museum between 1901 and 1902. There were also records of people buying merganser skins from sailors at Bluff Harbor for £3 10 shillings. The remaining population also went extinct under such intensive hunting.

The world's smallest merganser was sought in the Auckland Islands in 1909, 1927, and 1972-73, but all attempts failed. The Auckland Merganser was eventually deemed extinct, with its disappearance recorded as 1905.

Amsterdam Island Duck Mareca marecula

The Auckland Merganser at least has some specimen records left, but the next species to appear, the Assinus duck, is even more miserable. There are no complete specimens of them, and our limited understanding of them comes from early records and some subfossils and remains.

If we follow the English wording and say the full name, it should be Amsterdam Island Duck. However, this Amsterdam Island is not in Europe, but a small volcanic island in the Indian Ocean, with an area of ​​only 55 square kilometers. Whether it is Africa or Australia, the distance is more than 3,000 kilometers. In 1522, Spanish Basque explorer Sebastian Juan Elcano first saw this island during his circumnavigation of the world, but he did not name it. More than a hundred years later, in 1633, Dutch explorer Anthony van Diemen discovered the island again and named it after his ship "Amsterdam". In 1892, France officially occupied the island and established a research base on Amsterdam Island in 1949.

In 1955-1956, an incomplete duck skull was found on the island, and it was speculated that the unknown duck was similar in size to the white-browed duck. In subsequent surveys, thousands of bird bones were collected in caves on the island. Bones of this small duck were found in seven locations ranging from sea level to 500 meters above sea level, belonging to at least 33 different individuals, covering all important parts such as the skull, sternum, limb bones, and pelvis. At first, people thought that these bones belonged to the lost white-browed duck or South African duck, but further research showed that the hind legs of this duck were very strong, but the wings were very small and underdeveloped. They most likely lost the ability to fly and lived on the ground for their entire lives. Their salt glands (a gland that can excrete excess salt from the body) were not well developed, which means that they probably moved more inland. The bones also tell us that their beaks are short, and it is speculated that they are more closely related to the red-necked duck. In 1996, Olson and Jouventin confirmed that these unknown ducks were a separate species found on Amsterdam Island and St. Paul Island by examining their skeletons.

Although Amsterdam Island is far from the mainland, it is almost in the middle of the route from Africa to Australia, so many ships will stop here temporarily. It is located in the subantarctic zone and is rich in marine mammals. Therefore, long before the arrival of naturalists, whalers and sealers had already landed on the island to rest and seek supplies, and along with them, they brought rats. This undoubtedly posed a huge threat to the island duck. There were records that the island duck was "the favorite food of seal hunters living on the island." However, there is no written record of what the Lay Island duck looks like, what habits it has, and how many there are. As far as we know, in 1696, the Dutch explorer William de Vlaming saw two "quadrupeds similar to ferrets or foxes" in the reeds of Amsterdam Island. Because there were no native mammals on the island, some people speculated that these were Lay Island ducks.

In September 1792, the British delegation led by Macartney set sail from Southampton to distant China. On January 15, 1793, they rounded the Cape of Good Hope and entered the Indian Ocean. On February 2, John Barrow, an attaché of the delegation, saw "a little brown duck not much bigger than a thrush" on St. Paul Island near Amsterdam Island. This was just a seemingly insignificant episode in the long voyage of the Macartney delegation. It was not until much later that people knew that this was the last time humans had seen and recorded the appearance of the Assinus duck. At this time, it would take 203 years for people to know that this flightless duck was an independent species and give it a name.

Labrador Duck Labrador Duck Camptorhynchus labradorius

In November 1620, after two months of crossing the Atlantic Ocean, the Mayflower arrived in Massachusetts, which is the wintering place of Labrador ducks. With the increase in the number of European immigrants, this coastal area has become the most important population gathering area. In 1753, Linnaeus established the binomial system to name organisms. Many American species also have their own scientific names. The American goldfinch, turkey, mourning dove and cardinal were named in 1758, and the robin and passenger pigeon were named in 1766. The name was given by Linnaeus, indicating that they have long been known. The Labrador duck was published by the German naturalist Gmelin (JF) more than 20 years later in 1789. As a bird distributed in the eastern United States, with a large body, and a wintering area - the coastal coast from Nova Scotia, Canada to New Jersey, the United States today - highly overlapped with human activity areas, the Labrador duck was discovered relatively late. Perhaps the most appropriate explanation is that at that time, there were not many Labrador ducks. Less than a hundred years after its discovery, the Labrador duck disappeared completely from the Earth.

The cause of the Labrador duck's extinction is not very clear. Unlike the Atoll duck, it is possible that few people hunted Labrador ducks for food, as people thought that the ducks tasted bad. However, this does not mean that they were not threatened by hunting. Their wintering grounds were densely populated, and the craze for collecting specimens and bird eggs in the 19th century undoubtedly posed a threat to their survival. Among the existing Labrador duck specimens, some do not have information about who collected them and where they were collected. They may have come from the market or from unknown (and unaware) sailors or hunters. The feather trade may be another threat: the feather trade in Europe and the United States was very prosperous in the 19th century, and the great egrets and snowy egrets in North America were on the verge of extinction because of it. However, it is still impossible to assess how much of the Labrador duck's extinction is due to hunting.

The collection and trade of specimens has hit the population of Labrador ducks, and has also made the information in our hands richer today. At present, there are 55 specimens of Labrador ducks preserved - or 54, because the Labrador duck specimens stored in Halberstadt, Germany, only the beak comes from a real Labrador duck, and all other parts are pieced together from domestic ducks. These specimens tell us that Labrador ducks are about 54 cm long, roughly the same as ruddy ducks, and their beaks are straight at the front, which is very different from common ducks. The male bird has a white head, neck, and sides, black top, back, chest, abdomen and tail, and a black neck ring. The female bird is gray-brown all over, with only the secondary flight feathers being white. Their relatives are sea scoters, and their females look so similar that in a pair of Labrador duck specimens collected by McCulloch, the founder of Dalhousie University in Canada, the female is actually a black sea scoter.

There may be other factors that led to the extinction of the Labrador duck: they usually live near sandy beaches, and shellfish account for a high proportion of their diet, so they were originally called "beach ducks". With the increase in population and industrial development on the east coast of the United States, the number of mollusks may have dropped significantly, further leading to the decline in the number of Labrador ducks. Or perhaps environmental pollution also has a role here?

The wintering grounds of the Labrador duck are well-defined, but their breeding grounds are not. Judging from its scientific name, the specific epithet "Labrador" seems to indicate the breeding grounds, but there is no conclusive evidence. These places are still sparsely populated today, and few people visited them two hundred years ago. Although some eggs collected by explorers in the Arctic and labeled "Labrador duck" are still collected in museums or private hands, some studies have shown that they are eggs of eider ducks, mergansers, or even mallards.

Audubon, who is now in the spotlight, was also keen on finding and shooting Labrador ducks. In June 1833, Audubon set out with his son John Woodhouse Audubon and his son's four friends to the Labrador area. Audubon Jr. and his friends were responsible for hunting, while Audubon Sr. drew pictures in the camp - he might draw for 18 hours a day and make detailed records day by day. In the officially published description of the Labrador Duck painting, Audubon wrote that on July 28, his son and his friends "found several abandoned bird nests on the top of the low fir bushes. From the archives provided by British officials in the local fishing village, we learned that they were the nests of the mottled ducks (the name of the Labrador duck at the time)". However, in the diary of the same day, Audubon wrote that "the mottled ducks breed on the top of the low bushes, but the breeding season has not yet arrived, and we have not found their nests."

Audubon's diary also records other situations, such as people hunting birds for bait; in 1832, there were more than 20 boats engaged in the bird egg collection industry, and four people collected 40,000 bird eggs and sold them at 25 cents per dozen (12 eggs). Audubon lamented that within 50 years, this bird breeding ground would be destroyed. "Labrador will soon be deserted due to human greed. Not only will all non-native people leave here, but all living animals will disappear."

Forty-two years later, in the fall of 1875, the last Labrador duck was shot dead near Long Island, New York. It was a young male bird, and its specimen is kept in the Smithsonian Museum. There are also records showing that a Labrador duck was hunted in Elmira, New York on December 12, 1878, but this record is not supported by specimens or more evidence.

In addition to the above-mentioned ducks, some other ducks have also disappeared from the earth, especially those endemic to islands. Some of them may have become extinct soon after the arrival of Homo sapiens, such as Mauritius duck, Chatham merganser, Finn's duck, etc. The validity of some species has yet to be confirmed, such as New Zealand musk duck and New Zealand hard-tailed duck. Most of these extinctions are attributed to human hunting and the introduction of alien species, especially rats, cats, pigs and dogs. Unfortunately, their data are extremely limited, and there are even no complete specimens, so that we can only piece together their lives from scattered bones and fragments of words from early sailors and explorers, and we cannot even determine the time of their extinction.

Today, geese and ducks have not completely escaped the risk of extinction. Among the more than 170 duck species surviving in the world, 31 are still threatened with extinction. Among them, the Falkland Islands' Pochard, Baer's Pochard, Leys Island's Duck, and Brown Merganser are critically endangered species. The road to protecting geese and ducks is still long and arduous.

The article is produced by Science Popularization China-Starry Sky Project (Creation and Cultivation). Please indicate the source when reprinting.

Author: Cricket, editor of "China Bird Watch", deputy editor of "Illustrated Guide to Common Wild Birds in Beijing"

Reviewer: Huang Chengming, Researcher, Institute of Zoology, Chinese Academy of Sciences