Spotted whistling duck

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Spotted whistling duck
Spotted Whistling Duck RWD3.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Dendrocygna
Species:
D. guttata
Binomial name
Dendrocygna guttata
Schlegel, 1866

The spotted whistling duck (Dendrocygna guttata) is a member of the duck family Anatidae. It is also referred to as the "spotted tree duck". [2] This duck can be found in Indonesia, New Guinea, Australia and the Philippines. Spotted ducks are also held in captive populations.

Contents

Description

The Spotted whistling duck is one of the smaller species in the genus Dendrocygna. [3] This duck grows to 43–50 cm tall. Males can weigh anywhere from 590g to 650g while females weigh 610g to 860g. White spots on their flanks and breasts gave these ducks the spotted name. The sides of the neck, faces, and eyebrows are all grey. Black or dark brown coloring stretches from the crown nape to the hindneck. This dark coloring is also found in the eyepatch. Their coloring resembles a cape with a thick collar. This cape starts as a light brown then fades into a darker brown closer to the tail. Their underbelly is mostly brown, sometimes spotted, and significantly lighter than the wings and the “collar.” A white bar on the upper tail coverts can be seen during flight aiding in identification. They have dull pink legs [4] with black webbed feet and sharp nails. [5] The bill is dark, yet often seen with portions of red and a small white mark on the lower mandible. [6] Spotted whistling ducks look as though they are raised from the ground, as though they are standing up tall. [5] (look more into this). Their wings pressed strongly against the body. [5] Inner vanes of the outer primaries are jagged and can be seen in flight (check on this). [5] While flying, the head is positioned down causing the whole bird to look hunched. The tail stays pointed and looks long when in flight. [5] Juveniles are seen with white streaks on flanks instead of spots [4] and have significantly duller coloring. [6] Spotted whistling ducks are visually similar to D. arborea, yet many scientists believe its closest relative is D. eytoni. [6] After gaining their adult plumage at the age of 6 months,. [7] the spotted whistling duck has a single annual molt. [3] Like other ducks, swans, and geese, the spotted whistling duck molts synchronously. Synchronous molting is common within Anseriformes because waterfowl have the ability to avoid terrestrial predators. Unlike other birds, waterfowl float in ponds lakes while they molt, safe from predators. Other more evolved ducks have two molts, whistling ducks only molt once. [8]

Taxonomy and Systematics

The spotted whistling duck, Dendrocygna guttata, was first reported in 1866. [9] Like all other birds, it is an animal in the phylum Chordata and the class Aves. The spotted whistling duck is a part of the order Anseriformes, which includes all waterfowl. Swans, geese, and ducks are all a part of the family Anatidae. Within Anatidae, the family Dendrocygna encompasses all whistling ducks. [9] Bird phylogenies are difficult to determine due to massive adaptive radiations throughout history. Scientists change phylogenetic trees often as new genetic information becomes available. In Australia philogonies are especially difficult, due to visually similar endemic and monotypic genera. Before genetic information was available, the Dendrocygna was classified within Anserinae by Delacour and Mayr. Within Anserinae, the Dendrocygna and Thalassornis were combined into one by Monrow in 1990 using DNA-DNA hybridization data. This genus then stayed consistent. Using mitochondrial DNA in 1996 Swaml et al. discovered Dendrocyna diverged first following Anseranatidae. This genus is the most basal group after the magpie goose. Whistling ducks are more closely related to swans and geese than the “true ducks” such as mallards. [8] Then, in 2002 a study using sequenced DNA from the complete mitochondrial control region supported the 1996 conclusion. Within Denrocygna, the Spotted Whistling Duck was the most recent species discovery. In 1995 Livezey partitioned clades within the Dendrocygna, one clade including the Fulvous Whistling-Duck, Lesser whistling, D. arcuata and D. eytoni. D. arcuata and D. javanica are sister species. Outside this clade, the spotted whistling duck and the West Indian whistling duck are sister species. [8]

Distribution

Whistling ducks are found all over the world. The spotted whistling duck is distributed throughout the Philippines, Australia, and New Guinea. [6] These ducks live in the southern part of the Philippines and several islands of Indonesia. In Indonesia spotted whistling ducks stretch from the Eastern Lesser Sundas islands to new guinea. Spotted whistling ducks are also found in Weipa and Iron ranges of Australia, but have also been seen at Wonga Beach. Scientists hypothesize the Indonesian population was introduced due to a storm blowing the birds off course. [4]

Habitat

Spotted whistling ducks live around bodies of water, like many other ducks. These ducks specifically live around small ponds and marshes surrounded by trees. They prefer humid and low altitude habitats. [4] Spotted whistling ducks build hollows within the trees surrounding their habitats. [8]

Diet and Feeding

The Diet of the spotted whistling duck contains grass seeds, aquatic invertebrates, aquatic plants, and small fish. [6] These ducks obtain their food by dabbling and diving. The ducks dabble at the surface of the ponds, filtering the water through their bills. The birds bounce on the surface to enter the water headfirst, after being underwater for a maximum of 15 seconds they emerge with another bounce. Scientists never observed food in the bill after the diving behavior. They concluded the birds consume the food while underwater. [10] (Beruldsen) The majority of feeding occurs at night. [11]

Breeding

The genus Dendrocygna has strong pair bonds. Male and female birds are visually similar, females are slightly heavier than males. Without weighing the bird sex is difficult to determine. Breeding season begins in September with active nests found as late as April. Their nests are found in hollowed-out trees. Both parents participate in nest building at the same time. One pair can have several clutches a year consisting of 10-11 eggs. Both parents incubate the eggs [12] for 18–31 days and when hatched the chick weighs 17.5g. [6] In captivity, the chicks fledged at 7 weeks, [6] yet in the wild scientists have observed chicks flying at 45–50 days old. [5] The spotted whistling duck has a breeding system described as ‘primitive,’ which is consistent with other basal groups in Anseriformes. [3]

Behavior

Spotted whistling ducks are found in groups with their own species and often with D. arcata. [6] Compared to others in the genus, these ducks are less vocal. [5] These birds perch on tree branches in groups slightly smaller than flocks. The flocks are often a mix of adults and juveniles. The adults shepard the juveniles keeping them close to the group. In 2000 Beruldsen observed a group consisting of 6 juveniles and two adults, male and female. The juveniles seemed unbothered by the human presence, but the adults made sure there was distance between Buruldsen and the juveniles. The birds kept their distance but seemed to be unaffected. The adult male positioned himself between the juveniles and the humans, protecting the other birds. This behavior was often accompanied by several high-pitched ticking calls. [10]

Threats

The spotted whistling duck is listed as least concern. [1] Their population is stable with populations ranging from 10,000 to 25,000 birds. [6] In captivity they were found to be specifically susceptible to avian tuberculous. Twenty-seven percent of bird species get avian tuberculosis and the disease is usually fatal. Spotted whistling ducks die at a higher rate than other birds. Within one collection of captive birds, the death rate of avian tuberculous reached 70% with the majority of deaths occurring from January to March. The relatively small size of this bird could explain the increased death rate. [3]

Interactions with Humans

The spotted whistling duck is not hunted often. These ducks are found in captivity, like many other duck species. [12]

Related Research Articles

<span class="mw-page-title-main">Duck</span> Common name for many species of bird

Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form taxon; they do not represent a monophyletic group, since swans and geese are not considered ducks. Ducks are mostly aquatic birds, and may be found in both fresh water and sea water.

<span class="mw-page-title-main">Goose</span> Common name for a group of waterfowl

A goose is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera Anser and Branta. Some other birds, mostly related to the shelducks, have "goose" as part of their names. More distantly related members of the family Anatidae are swans, most of which are larger than true geese, and ducks, which are smaller.

<span class="mw-page-title-main">Anatidae</span> Biological family of water birds

The Anatidae are the biological family of water birds that includes ducks, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted for swimming, floating on the water surface, and in some cases diving in at least shallow water. The family contains around 174 species in 43 genera.

<span class="mw-page-title-main">Anseriformes</span> Order of water birds

Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae, Anseranatidae, and Anatidae, the largest family, which includes over 170 species of waterfowl, among them the ducks, geese, and swans. Most modern species in the order are highly adapted for an aquatic existence at the water surface. With the exception of screamers, males have penises, a trait that has been lost in the Neoaves. Due to their aquatic nature, most species are web-footed.

<span class="mw-page-title-main">Oxyurini</span> Tribe of birds

The Oxyurini are a tribe of the duck subfamily of birds, the Anatinae. It has been subject of considerable debate about its validity and circumscription. Some taxonomic authorities place the group in its own subfamily, the Oxyurinae. Most of its members have long, stiff tail feathers which are erected when the bird is at rest, and relatively large, swollen bills. Though their relationships are still enigmatic, they appear to be closer to swans and true geese than to the typical ducks. The highest diversity is found in the warmer parts of the Americas, but at least one species occurs in a major part of the world.

<span class="mw-page-title-main">Tadorninae</span> Subfamily of birds

The Tadorninae is the shelduck-sheldgoose subfamily of the Anatidae, the biological family that includes the ducks and most duck-like waterfowl such as the geese and swans.

<span class="mw-page-title-main">Blue-winged teal</span> Species of bird

The blue-winged teal is a species of bird in the duck, goose, and swan family Anatidae. One of the smaller members of the dabbling duck group, it occurs in North America, where it breeds from southern Alaska to Nova Scotia, and south to northern Texas. It winters along the Pacific and Atlantic coasts and south into the Caribbean islands and Central America.

<i>Tadorna</i> Genus of birds

The shelducks, most species of which are found in the genus Tadorna, are a group of large birds in the Tadorninae subfamily of the Anatidae, the biological family that includes the ducks and most duck-like waterfowl such as the geese and swans.

<span class="mw-page-title-main">Coscoroba swan</span> Species of bird

The coscoroba swan is a species of waterfowl in the subfamily Anserinae of the family Anatidae. It is found in Argentina, Bolivia, Brazil, Chile, Paraguay, Uruguay, and the Falkland Islands.

<span class="mw-page-title-main">Magpie goose</span> Species of bird

The magpie goose is the sole living representative species of the family Anseranatidae. This common waterbird is found in northern Australia and southern New Guinea. As the species is prone to wandering, especially when not breeding, it is sometimes recorded outside its core range. The species was once also widespread in southern Australia but disappeared from there largely due to the drainage of the wetlands where the birds once bred. Due to their importance to Aboriginal people as a seasonal food source, as subjects of recreational hunting, and as a tourist attraction, their expansive and stable presence in northern Australia has been "ensured [by] protective management".

<span class="mw-page-title-main">Lesser whistling duck</span> Species of bird

The lesser whistling duck, also known as Indian whistling duck or lesser whistling teal, is a species of whistling duck that breeds in the Indian subcontinent and Southeast Asia. They are nocturnal feeders that during the day may be found in flocks around lakes and wet paddy fields. They can perch on trees and sometimes build their nest in the hollow of a tree. This brown and long-necked duck has broad wings that are visible in flight and produces a loud two-note wheezy call. It has a chestnut rump, differentiating it from its larger relative, the fulvous whistling duck, which has a creamy white rump.

<span class="mw-page-title-main">White-faced whistling duck</span> Species of bird

The white-faced whistling duck is a whistling duck that breeds in sub-Saharan Africa and much of South America.

<span class="mw-page-title-main">Comb duck</span> Species of bird

The comb duck or American comb duck, is an unusual duck, found in tropical wetlands in continental South America south to the Paraguay River region in eastern Paraguay, southeastern Brazil and extreme northeastern Argentina, and as a vagrant on Trinidad.

<i>Anas</i> Genus of birds

Anas is a genus of dabbling ducks. It includes the pintails, most teals, and the mallard and its close relatives. It formerly included additional species but following the publication of a molecular phylogenetic study in 2009 the genus was split into four separate genera. The genus now contains 31 living species. The name Anas is the Latin for "duck".

<span class="mw-page-title-main">Fulvous whistling duck</span> Species of bird in the family Anatidae, widespread in tropical wetlands

The fulvous whistling duck or fulvous tree duck is a species of whistling duck that breeds across the world's tropical regions in much of Mexico and South America, the West Indies, the southern United States, sub-Saharan Africa and the Indian subcontinent. It has plumage that is mainly reddish brown, long legs and a long grey bill, and shows a distinctive white band across its black tail in flight. Like other members of its ancient lineage, it has a whistling call which is given in flight or on the ground. Its preferred habitat consists of wetlands with plentiful vegetation, including shallow lakes and paddy fields. The nest, built from plant material and unlined, is placed among dense vegetation or in a tree hole. The typical clutch is around ten whitish eggs. The breeding adults, which pair for life, take turns to incubate, and the eggs hatch in 24–29 days. The downy grey ducklings leave the nest within a day or so of hatching, but the parents continue to protect them until they fledge around nine weeks later.

<span class="mw-page-title-main">Australian wood duck</span> Species of bird

The Australian wood duck, maned duck or maned goose is a dabbling duck found throughout much of Australia. It is the only living species in the genus Chenonetta. Traditionally placed in the subfamily Anatinae, it might belong to the subfamily Tadorninae (shelducks); the ringed teal may be its closest living relative.

<span class="mw-page-title-main">Pygmy goose</span> Genus of birds

The pygmy geese are a group of very small "perching ducks" in the genus Nettapus which breed in the Old World tropics. They are the smallest of all wildfowl. As the "perching ducks" are a paraphyletic group, they need to be placed elsewhere. The initially assumed relationship with the dabbling duck subfamily Anatinae has been questioned, and it appears they form a lineage in an ancient Gondwanan radiation of waterfowl, within which they are of unclear affinities. An undescribed fossil species from the late Hemphillian of Jalisco, central Mexico, has also been identified from the distal end of a tarsometatarsus. It is only record of the genus in the New World.

<span class="mw-page-title-main">Whistling duck</span> Subfamily of birds

The whistling ducks or tree ducks are a subfamily, Dendrocygninae, of the duck, goose and swan family of birds, Anatidae. In other taxonomic schemes, they are considered a separate family, Dendrocygnidae. Some taxonomists list only one genus, Dendrocygna, which contains eight living species, and one undescribed extinct species from Aitutaki of the Cook Islands, but other taxonomists also list the white-backed duck under the subfamily.

<span class="mw-page-title-main">Black-bellied whistling duck</span> Species of bird

The black-bellied whistling duck, formerly called the black-bellied tree duck, is a whistling duck that before 2000 bred mainly in the southernmost United States, Mexico, and tropical Central to south-central South America. It can be found year-round in much of the United States. It has been recorded in every eastern state and adjacent Canadian province. Since it is one of only two whistling duck species native to North America, it is occasionally just known as the "whistling duck" or "Mexican squealer" in the southern USA.

<span class="mw-page-title-main">Plumed whistling duck</span> Species of duck

The plumed whistling duck, also called the grass whistling duck, is a whistling duck that breeds in Australia. It is a predominantly brown-coloured duck with a long neck and characteristic plumes arising from its flanks. The sexes are similar in appearance.

References

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  2. Johnstone, R.E. (2013). The Birds of the Kai and Tayandu Islands, Maluku region, Indonesia (29 ed.). Western Australian Naturalist. pp. 11–56.
  3. 1 2 3 4 Hillgarth, Kear, Nigella, Janet (1982). "Causes of Mortality among Whistling Ducks in Captivity". Wildfowl Journal (33): 133–139.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. 1 2 3 4 Kyne, Peter M. (2013). "First record of Spotted Whistling Duck Dendrocygna guttata for the Northern Territory". Northern Territory Naturalist (24): 50–54.
  5. 1 2 3 4 5 6 7 Guadagnini, Davide. "Dendrocygna guttata". Momaco Nature Encyclopedia. Monaco Nature Encyclopedia.
  6. 1 2 3 4 5 6 7 8 9 Carboneras, Kirwan, C., G.M. "Spotted Whistling Duck (Dendrocygna guttata)". Cornell Lab of Ornithology. Cornell University.{{cite web}}: CS1 maint: multiple names: authors list (link)
  7. Johnsgard, Paul (1965). "Handbook of WaterFowl Behavior: Tribe Dendrocygnini". Papers in the Biological Sciences: 14–24.
  8. 1 2 3 4 "Whistling Ducks". Ducks Unlimited.
  9. 1 2 Christidis, Boles, Les, Walter (2008). Systematics and Taxonomy of Australian Birds. Csiro Publishing. p. 14.{{cite book}}: CS1 maint: multiple names: authors list (link)
  10. 1 2 Beruldsen, Gordon (2002). "Spotted Whistling-Duck Probably Breeding in Australia". Australian Bird Watcher (19): 143–146.
  11. "Spotted Whistling Ducks". Beauty of Birds.
  12. 1 2 "Spotted Whistling Duck". British Waterfowl Association.