Jump to content

Freckled duck: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
No edit summary
Fixed links
Tags: Mobile edit Mobile app edit iOS app edit
 
(33 intermediate revisions by 32 users not shown)
Line 1: Line 1:
{{short description|Species of bird}}
{{use dmy dates|date=May 2011}}
{{Use dmy dates|date=September 2020}}
{{use Australian English|date=May 2011}}
{{use Australian English|date=May 2011}}
{{speciesbox
{{speciesbox
Line 5: Line 6:
| status = LC
| status = LC
| status_system = IUCN3.1
| status_system = IUCN3.1
| status_ref = <ref name=IUCN>{{cite journal | authors = BirdLife International| title = ''Stictonetta naevosa'' | journal = [[IUCN Red List of Threatened Species]] | volume= 2016| page = e.T22679836A92831716 | publisher = [[IUCN]] | year = 2016| url = http://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T22679836A92831716.en| accessdate = 17 January 2017}}</ref>
| status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=BirdLife International |date=2016 |title=''Stictonetta naevosa'' |volume=2016 |page=e.T22679836A92831716 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22679836A92831716.en |access-date=19 November 2021}}</ref>
| image = Freckled-Duck-male.jpg
| image = Freckled-Duck-male.jpg
| image_caption = Male
| image_caption = Male
| image2 = Freckled-duck-female.jpg
| image2 = Freckled-duck-female.jpg
| image2_caption = Female
| image2_caption = Female
| grandparent_authority = Boetticher, 1950
| grandparent_authority = [[Hans von Boetticher|Boetticher]], 1950
| genus = Stictonetta
| genus = Stictonetta
| parent_authority = [[Ludwig Reichenbach|L. Reichenbach]], 1853
| parent_authority = [[Ludwig Reichenbach|Reichenbach]], 1853
| display_parents = 3
| display_parents = 3
| species = naevosa
| species = naevosa
Line 18: Line 19:
}}
}}


The '''freckled duck''' (''Stictonetta naevosa)'' is a waterfowl species endemic to Australia. The freckled duck has also been referred to as the monkey duck or the oatmeal duck.<ref name=:21>{{cite book|last=Johnsgard|first=P. A.|year=2010|chapter=Tribe Stictonettini (Freckled Duck)|title=Ducks, Geese, and Swans of the World|pages=97–100|url=http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1006&context=biosciducksgeeseswans}}</ref> These birds are usually present in mainland Australia, but disperse to coastal and subcostal [[wetland]]s in the dry period. During such times it is common for the freckled duck population to congregate in flocks in the same area, giving the impression that they are more common than they really are.<ref name=:16>{{cite report|last=Garnett|first=S.|year=1992|title=The Action Plan for Australian Birds|location=Canberra|publisher=Australian National Parks and Wildlife Service}}</ref>
The '''freckled duck''' ('''''Stictonetta naevosa''')'' is a waterfowl species endemic to Australia. The freckled duck has also been referred to as the '''monkey duck''' or '''oatmeal duck'''.<ref name=:21>{{cite book|last=Johnsgard|first=P. A.|year=2010|chapter=Tribe Stictonettini (Freckled Duck)|title=Ducks, Geese, and Swans of the World|pages=97–100|chapter-url=http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1006&context=biosciducksgeeseswans}}</ref> These birds are usually present in mainland Australia, but disperse to coastal and subcostal [[wetland]]s in the dry period. During such times it is common for the freckled duck population to congregate in flocks in the same area, giving the impression that they are more common than they really are.<ref name=:16>{{cite report|last=Garnett|first=S.|year=1992|title=The Action Plan for Australian Birds|location=Canberra|publisher=Australian National Parks and Wildlife Service}}</ref>


The freckled duck population is at risk of further reduction from habitat destruction, droughts and game hunting. Often habitat destruction and drought can lead to an increase in hunting, as the freckled duck is forced to disperse into more coastal ranges where they may not be recognised as a protected species.<ref name=:23>{{cite journal|last=Loyn|first=R. H.|year=1991|title=Assessing and managing the impact of duck hunting in Victoria - a new approach|journal=Wildfowl|volume=42|pages=155–161}}</ref>
The freckled duck population is at risk of further reduction from [[habitat destruction]], droughts and game hunting. Often habitat destruction and drought can lead to an increase in hunting, as the freckled duck is forced to disperse into more coastal ranges where they may not be recognised as a protected species.<ref name=:23>{{cite journal|last=Loyn|first=R. H.|year=1991|title=Assessing and managing the impact of duck hunting in Victoria - a new approach|journal=Wildfowl|volume=42|pages=155–161}}</ref>


In the past few decades, several institutions have established breeding programs to aid in supplementation of the freckled duck population. Such establishments included, but are not restricted to the Hunter Wetlands Australia, [[Slimbridge Wetland Reserve|Slimbridge Wetlands]], Melbourne Zoo, [[Bronx Zoo]], [[Adelaide Zoo]], [[Healesville Sanctuary]] and [[Tidbinbilla Nature Reserve]].<ref name=:28/> The success of these institutes has been variable, with some failing to establish self-maintaining colonies.
In the past few decades, several institutions have established breeding programs to aid in supplementation of the freckled duck population. Such establishments included, but are not restricted to the [[Hunter Estuary Wetlands|Hunter Wetlands Centre Australia]],<ref>{{cite web |title=Frecked Ducks in Residence |url=https://wetlands.org.au/living_wetlands/freckled-ducks-in-residence/ |website=Hunter Wetlands Centre Australia |access-date=13 May 2023}}</ref> [[Slimbridge Wetland Reserve|Slimbridge Wetlands]], [[Melbourne Zoo]], [[Bronx Zoo]], [[Adelaide Zoo]], [[Healesville Sanctuary]], and [[Tidbinbilla Nature Reserve]].<ref name=:28/> The success of these institutes has been variable, with some failing to establish self-maintaining colonies.


==Description==
==Description==


The freckled duck has a distinctive appearance. It is characterised, in adults, by dark grey to black plumage covered with small white flecks, which gives the duck the ‘freckled’ look. The feet, legs and bill of both sexes is of a slate grey colour. Hatchlings and juveniles are distinguished by a uniform light grey plumage, which they lose around their 32nd week when they undergo a full body moult to assume the adult plumage.<ref name=:26>{{cite journal|last1=Norman|first1=F. I.|last2=Norris|first2=K. C.|year=1982|title=Some notes on Freckled Duck shot in Victoria, Australia, 1981|journal=Wildfowl|volume=33|pages=81–87}}</ref>
The freckled duck has a distinctive appearance. It is characterised, in adults, by dark grey to black plumage covered with small white flecks, which gives the duck the 'freckled' look. The feet, legs and bill of both sexes is of a slate grey colour. Hatchlings and juveniles are distinguished by a uniform light grey plumage, which they lose around their 32nd week when they undergo a full body moult to assume the adult plumage.<ref name=:26>{{cite journal|last1=Norman|first1=F. I.|last2=Norris|first2=K. C.|year=1982|title=Some notes on Freckled Duck shot in Victoria, Australia, 1981|journal=Wildfowl|volume=33|pages=81–87}}</ref>


The adult freckled displays a few sexual dimorphisms, the first being size. On average, males are the larger sex, with average weight between 700 - 1200g. Females have an only slightly lower range between 600 – 1200g. Both sexes have a length of 50 – 60&nbsp;cm. During the breeding season particularly, the males are characterised by the base of their [[Beak|culmen]], which takes on various shades of red. Those in prime reproductive condition take on a deep red colouring, while other males may only develop lighter shades of red, or in some instances, no colouring at all. Deep red colouring of the culmen is also associated with dominance, and those with the deepest red are those likely to breed with the females of the group.<ref name=:28>{{cite journal|last1=Wilson|first1=S.|last2=Silcocks|first2=S.|year=2001|title=The husbandry and breeding of the freckled duck at Melbourne Zoo|journal=Australian Birdkeeper|volume=14|issue=9|pages=524–527}}</ref>
The adult freckled duck is [[Sexual dimorphism|sexually dimorphic]]. On average, males are the larger sex, with average weight between 700 - 1200&nbsp;g. Females have an only slightly lower range between 600 – 1200&nbsp;g. Both sexes have a length of 50 – 60&nbsp;cm. During the breeding season particularly, the males are characterised by the base of their [[Beak|culmen]], which takes on various shades of red. Those in prime reproductive condition take on a deep red colouring, while other males may only develop lighter shades of red, or in some instances, no colouring at all. Deep red colouring of the culmen is also associated with dominance, and those with the deepest red are those likely to breed with the females of the group.<ref name=:28>{{cite journal|last1=Wilson|first1=S.|last2=Silcocks|first2=S.|year=2001|title=The husbandry and breeding of the freckled duck at Melbourne Zoo|journal=Australian Birdkeeper|volume=14|issue=9|pages=524–527}}</ref>


==Distribution and habitat==
==Distribution and habitat==
[[File:Freckled Duck female RWD3.jpg|thumb|left|Female at Sylvan Heights Waterfowl Park in Scotland Neck, North Carolina]]
[[File:Freckled Duck female RWD3.jpg|thumb|left|Female at Sylvan Heights Waterfowl Park in Scotland Neck, North Carolina]]
Endemic to Australia, the freckled duck is mainly situated throughout inland regions of the Eastern section of the country—including New South Wales, Victoria and Queensland. This species also has known populations in South Australia and Western Australia.<ref name=:24>{{cite journal|last1=Maher|first1=M. T.|last2=Braithwaite|first2=L. W.|year=1992|title=Patterns of waterbird use in wetlands of the Paroo, A river system of inland Australia|journal=The Rangeland Journal|volume=14|issue=2|pages=128–142}}</ref> Due to habitat requirements, distribution of the freckled duck directly correlates to water flow and rainfall in river catchments and wetland systems.<ref name=:10>{{cite web|publisher=Department of Environment and Heritage NSW|year=2016|title=Freckled Duck (Stictonetta naevosa)|url=http://www.environment.nsw.gov.au/savingourspeciesapp/project.aspx?ProfileID=10771}}</ref> Because of this, main populations of this species are located within the Paroo-Warrego catchment (Currawinya Lakes), Eyre-Georgine-Mulligan catchment (Lake Torquinie), and potentially at Lake Galilee. High numbers have also been recorded at the Cooper’s Creek catchment, wetlands within the Barkley Tablelands, the Bulloo River catchment and Lake Gregory in central north Western Australia.<ref name=:24/>
Endemic to Australia, the freckled duck is mainly situated throughout inland regions of the Eastern section of the country—including New South Wales, Victoria and Queensland. This species also has known populations in South Australia and Western Australia.<ref name=:24>{{cite journal|last1=Maher|first1=M. T.|last2=Braithwaite|first2=L. W.|year=1992|title=Patterns of waterbird use in wetlands of the Paroo, A river system of inland Australia|journal=The Rangeland Journal|volume=14|issue=2|pages=128–142|doi=10.1071/rj9920128}}</ref> Due to habitat requirements, distribution of the freckled duck directly correlates to water flow and rainfall in river catchments and wetland systems.<ref name=:10>{{cite web|publisher=Department of Environment and Heritage NSW|year=2016|title=Freckled Duck (Stictonetta naevosa)|url=http://www.environment.nsw.gov.au/savingourspeciesapp/project.aspx?ProfileID=10771}}</ref> Because of this, main populations of this species are located within the Paroo-Warrego catchment (Currawinya Lakes), Eyre-Georgine-Mulligan catchment (Lake Torquinie), and potentially at Lake Galilee. High numbers have also been recorded at the Cooper's Creek catchment, wetlands within the Barkley Tablelands, the Bulloo River catchment and Lake Gregory in central north Western Australia.<ref name=:24/>


Freckled duck habitat preference can be split into two distinct categories: breeding and non-breeding habitat. While this species does not appear to have any sort of distinct migratory pathway or seasonal migration to find suitable breeding habitat.<ref name=:1>{{cite book|last1=Blakers|first1=M.|last2=Davies|first2=S.|last3=Reilly|first3=P. N.|year=1984|title=The Atlas of Australian Birds|location=Melbourne|publisher=Melbourne University Press}}</ref> The freckled duck sometimes travels long distances to find a suitable breeding location, and seems to prefer large bodies of fresh water with thick vegetation. Usual contenders are recently flooded wetland systems and swamps.<ref name=:10/> After breeding, the freckled duck disperses to more coastal areas with more permanent bodies of water such as lakes, reservoirs, and ponds. These areas are often more exposed and contain little vegetation.<ref name=:25>{{cite book|last=Martindale|first=J.|year=1986|title=The Freckled Duck|location=Moonee Ponds, Victoria|publisher=Royal Australasian Ornithologists' Union}}</ref>
Freckled duck habitat preference can be split into two distinct categories: breeding and non-breeding habitat. While this species does not appear to have any sort of distinct migratory pathway or seasonal migration to find suitable breeding habitat.<ref name=:1>{{cite book|last1=Blakers|first1=M.|last2=Davies|first2=S.|last3=Reilly|first3=P. N.|year=1984|title=The Atlas of Australian Birds|location=Melbourne|publisher=Melbourne University Press}}</ref> The freckled duck sometimes travels long distances to find a suitable breeding location, and seems to prefer large bodies of fresh water with thick vegetation. Usual contenders are recently flooded wetland systems and swamps.<ref name=:10/> After breeding, the freckled duck disperses to more coastal areas with more permanent bodies of water such as lakes, reservoirs, and ponds. These areas are often more exposed and contain little vegetation.<ref name=:25>{{cite book|last=Martindale|first=J.|year=1986|title=The Freckled Duck|location=Moonee Ponds, Victoria|publisher=Royal Australasian Ornithologists' Union}}</ref>
Line 39: Line 40:
===Diet===
===Diet===


The diet of the freckled duck has been subjected to a degree of controversy and disagreement over the years, potentially due to the versatile diet of different populations and distributions of this duck. Despite this, it is widely agreed that the freckled duck is a resilient, specialist [[filter feeder]] that consumes a range of aquatic vegetation, insects, algae, larvae and crustaceans.<ref name=:27>{{cite journal|last1=Norman|first1=F. I.|last2=Brown|first2=R. S.|year=1985|title=Gizzard grit in some Australian waterfowl|journal=Wildfowl|volume=36|pages=77–80}}</ref><ref name=:6>{{cite journal|last=Corrick|first=A. H.|year=1980|title=Freckled Ducks on lakes in the Western District, Victoria|journal=Australian Bird Watcher|volume=8|issue=1|pages=254–255}}</ref> Studies have found that the freckled duck prefers to feed in shallow water, using its bill to strain food particles from the mud or sand.<ref name=:8>{{cite journal|last=Crome|first=F. H.|year=1985|title=An Experimental Investigation of Filter-Feeding on Zooplankton by Some Specialized Waterfowl|journal=Australian Journal of Zoology|volume=33|issue=6|pages=849–862}}</ref>
The diet of the freckled duck has been subjected to a degree of controversy and disagreement over the years, potentially due to the versatile diet of different populations and distributions of this duck. Despite this, it is widely agreed that the freckled duck is a resilient, specialist [[filter feeder]] that consumes a range of aquatic vegetation, insects, algae, larvae and crustaceans.<ref name=:27>{{cite journal|last1=Norman|first1=F. I.|last2=Brown|first2=R. S.|year=1985|title=Gizzard grit in some Australian waterfowl|journal=Wildfowl|volume=36|pages=77–80}}</ref><ref name=:6>{{cite journal|last=Corrick|first=A. H.|year=1980|title=Freckled Ducks on lakes in the Western District, Victoria|journal=Australian Bird Watcher|volume=8|issue=1|pages=254–255}}</ref> Studies have found that the freckled duck prefers to feed in shallow water, using its bill to strain food particles from the mud or sand.<ref name=:8>{{cite journal|last=Crome|first=F. H.|year=1985|title=An Experimental Investigation of Filter-Feeding on Zooplankton by Some Specialized Waterfowl|journal=Australian Journal of Zoology|volume=33|issue=6|pages=849–862|doi=10.1071/zo9850849}}</ref>


===Social behaviour===
===Social behaviour===
[[File:The birds of Australia (16769491056).jpg|thumb|right|Illustration from [[The Birds of Australia (Broinowski)|The Birds of Australia]] (1890)]]
[[File:The birds of Australia (16769491056).jpg|thumb|right|Illustration from [[The Birds of Australia (Broinowski)|The Birds of Australia]] (1890) (with [[Pacific black duck]])]]
A highly gregarious species, the freckled duck is known to have flock sizes ranging from 10-100 individuals, especially outside of breeding season. During breeding season, these flocks often break up into smaller sub-units, scattered throughout wetland and swamp systems.<ref name=:7>{{cite report|last=Craig|first=M.|year=1994|title=Captive species management plan for freckled duck: Stictonetta naevosa|location=Parkville, Victoria|publisher=Zoological Board of Victoria}}</ref>
A highly gregarious species, the freckled duck is known to have flock sizes ranging from 10 to 100 individuals, especially outside of breeding season. During breeding season, these flocks often break up into smaller sub-units, scattered throughout wetland and swamp systems.<ref name=:7>{{cite report|last=Craig|first=M.|year=1994|title=Captive species management plan for freckled duck: Stictonetta naevosa|location=Parkville, Victoria|publisher=Zoological Board of Victoria}}</ref>


Despite these large flock sizes, this species is lacking in demonstrative displays towards one another, with only cryptic gestures and few interactions towards fellow flock mates. The rare interaction that is observed within this species is usually of a quarrelsome nature.<ref>{{cite journal|last1=Fullagar|first1=P. J.|last2=Davey|first2=C. C.|last3=Rushton|first3=D. K.|year=1990|title=Social behaviour of the Freckled Duck Stictonetta naevosa with particular reference to the Axle-grind|journal=Wildfowl|volume=41|pages=53–61}}</ref>
Despite these large flock sizes, this species is lacking in demonstrative displays towards one another, with only cryptic gestures and few interactions towards fellow flock mates. The rare interaction that is observed within this species is usually of a quarrelsome nature.<ref>{{cite journal|last1=Fullagar|first1=P. J.|last2=Davey|first2=C. C.|last3=Rushton|first3=D. K.|year=1990|title=Social behaviour of the Freckled Duck Stictonetta naevosa with particular reference to the Axle-grind|journal=Wildfowl|volume=41|pages=53–61}}</ref>
Line 49: Line 50:
===Bathing===
===Bathing===


While there has been little research into the bathing behaviour of the freckled duck, it is known that a body of water (e.g. a swamp or dam) is essential for many natural behaviours such as feeding, mating and bathing.<ref name=:2>{{cite journal|last=Braithwaite|first=L. W.|year=1976|title=Notes on the breeding of the Freckled Duck in the Lachlan River Valley|journal=Emu|volume=76|issue=3|pages=127–132}}</ref> Freckled ducks have been observes preening both within water and after emerging from water while in a roosting position.<ref name=:12>{{cite journal|last=Frith|first=H. J.|year=1964|title=The downy young of the Freckled Duck, Stictonetta naevosa|journal=Emu|volume=64|issue=1|pages=42–47}}</ref> There is no evidence that the freckled duck dust bathes or requires any other substrate for bathing.
While there has been little research into the bathing behaviour of the freckled duck, it is known that a body of water (e.g. a swamp or dam) is essential for many natural behaviours such as feeding, mating and bathing.<ref name=:2>{{cite journal|last=Braithwaite|first=L. W.|year=1976|title=Notes on the breeding of the Freckled Duck in the Lachlan River Valley|journal=Emu|volume=76|issue=3|pages=127–132|doi=10.1071/mu9760127}}</ref> Freckled ducks have been observes preening both within water and after emerging from water while in a roosting position.<ref name=:12>{{cite journal|last=Frith|first=H. J.|year=1964|title=The downy young of the Freckled Duck, Stictonetta naevosa|journal=Emu|volume=64|issue=1|pages=42–47|doi=10.1071/mu964042}}</ref> There is no evidence that the freckled duck dust bathes or requires any other substrate for bathing.


===Reproductive behaviour===
===Reproductive behaviour===


The freckled duck is a [[Polygyny|polygamous]] species that undertakes short term, seasonal [[Monogamy in animals|monogamous]] pairings in the wild. In this short term pairing, the male defends the receptive female during the pre-egg laying stage of the breeding season. During this time, the male also helps construct and defend the nest site—but leaves before the female lays her clutch, and plays no further role in rearing or defending his offspring.
The freckled duck is a [[Animal sexual behaviour#Polygamy|polygamous]] species that undertakes short term, seasonal [[Monogamy in animals|monogamous]] pairings in the wild. In this short term pairing, the male defends the receptive female during the pre-egg laying stage of the breeding season. During this time, the male also helps construct and defend the nest site—but leaves before the female lays her clutch, and plays no further role in rearing or defending his offspring.


The freckled duck has few pre or post [[copulatory]] behaviours. Copulation occurs in the water with the male approaching a receptive female who, adopts a semi-submerged orientation, with her head stretched outwards and tail raised. The male then mounts the female and clutches the feathers on the lower neck of the female during copulation. After dismounting, both sexes display bathing and preening behaviours.
The freckled duck has few pre or post [[Copulation (zoology)|copulatory]] behaviours. Copulation occurs in the water with the male approaching a receptive female, who adopts a semi-submerged orientation, with her head stretched outwards and tail raised. The male then mounts the female and clutches the feathers on the lower neck of the female during copulation. After dismounting, both sexes display bathing and preening behaviours.


The breeding season of the freckled duck is basically regular, with a generic breeding season between September and December. However, it retains the ability to breed out of season. Breeding out of season highly correlates with periods of heavy rainfall and flooding.
The breeding season of the freckled duck is basically regular, with a generic breeding season between September and December. However, it retains the ability to breed out of season. Breeding out of season highly correlates with periods of heavy rainfall and flooding.
Line 62: Line 63:
Both male and female freckled ducks reach sexual maturity at around 12 months of ages when the first breeding occurrence can commence. The freckled duck has been known to continue breeding annually throughout their life, with records suggesting successful breeding in birds in excess to 10 years of age.<ref name=:28/>
Both male and female freckled ducks reach sexual maturity at around 12 months of ages when the first breeding occurrence can commence. The freckled duck has been known to continue breeding annually throughout their life, with records suggesting successful breeding in birds in excess to 10 years of age.<ref name=:28/>


The freckled duck has a standard [[Incubation period|incubation]] period of between 26–28 days, though some sources have recorded incubation periods of up to 35 days. The female is solely responsible for egg incubation and only leaves the eggs for short periods to feed.
The freckled duck has a standard [[Incubation period|incubation]] period of between 26 and 28 days, though some sources have recorded incubation periods of up to 35 days. The female is solely responsible for egg incubation and only leaves the eggs for short periods to feed.


The average clutch is seven eggs, but can range between four and 14 eggs.<ref name=:4>{{cite journal|last=Briggs|first=S. V.|year=1982|title=Food habits of the Freckled Duck and associated waterfowl in North-western New South Wales|journal=Wildfowl|volume=33|pages=88–93}}</ref> Clutches of up to 14 eggs can occur naturally, though this occurrence mainly appears to be the result of females ‘dumping’ additional eggs into another female’s nest. This occurrence is common within freckled duck populations as it enables the offending females to pass on their genetic material while not expending energy to raise their hatchlings.<ref name=:19>{{cite journal|last=Jaensch|first=R.|year=2003|title=Breeding by freckled Duck Stictonetta naevosa in the Diamantina Channel Country|journal=Sunbird: The Journal of the Queensland Ornithological Society|volume=33|issue=1|pages=24–28}}</ref>
The average clutch is seven eggs, but can range between four and 14 eggs.<ref name=:4>{{cite journal|last=Briggs|first=S. V.|year=1982|title=Food habits of the Freckled Duck and associated waterfowl in North-western New South Wales|journal=Wildfowl|volume=33|pages=88–93}}</ref> Clutches of up to 14 eggs can occur naturally, though this occurrence mainly appears to be the result of females 'dumping' additional eggs into another female's nest. This occurrence is common within freckled duck populations as it enables the offending females to pass on their genetic material while not expending energy to raise their hatchlings.<ref name=:19>{{cite journal|last=Jaensch|first=R.|year=2003|title=Breeding by freckled Duck Stictonetta naevosa in the Diamantina Channel Country|journal=Sunbird: The Journal of the Queensland Ornithological Society|volume=33|issue=1|pages=24–28}}</ref>


The eggs of the freckled duck are glossy, smooth and almost perfectly oval in shape. They are white in colour, ranging from shades of cream to ivory. The freckled duck egg is unique, having an exceptionally thick but soft shell unlike that of any other species. Egg measurements usually fall between 60-65mm by 45-48mm and weigh an average of 66g.<ref name=:13>{{cite journal|last=Frith|first=H. K.|year=1965|title=Ecology of the Freckled Duck Stichonetta naevosa (Gould)|journal=CSIRO Wildlife Research|volume=10|issue=1|pages=125–139}}</ref>
The eggs of the freckled duck are glossy, smooth and almost perfectly oval in shape. They are white in colour, ranging from shades of cream to ivory. The freckled duck egg is unique, having an exceptionally thick but soft shell unlike that of any other species. Egg measurements usually fall between 60-65mm by 45-48mm and weigh an average of 66g.<ref name=:13>{{cite journal|last=Frith|first=H. K.|year=1965|title=Ecology of the Freckled Duck Stichonetta naevosa (Gould)|journal=CSIRO Wildlife Research|volume=10|issue=1|pages=125–139|doi=10.1071/cwr9650125}}</ref>


Freckled duck hatchlings are [[precocial]], meaning they hatch fully functional and able to feed themselves. Despite this, they still need their mother for the best chance of survival. Apart from protection, the hatchlings need the mother to teach them important social cues and behaviours.<ref name=:22>{{cite book|last=Kear|first=J.|year=2005|title=Ducks, Geese and Swans|volume=2: Species Accounts (Cairina to Mergus)|location=Oxford|publisher=Oxford University Press}}</ref>
Freckled duck hatchlings are [[precocial]], meaning they hatch fully functional and able to feed themselves. Despite this, they still need their mother for the best chance of survival. Apart from protection, the hatchlings need the mother to teach them important social cues and behaviours.<ref name=:22>{{cite book|last=Kear|first=J.|year=2005|title=Ducks, Geese and Swans|volume=2: Species Accounts (Cairina to Mergus)|location=Oxford|publisher=Oxford University Press}}</ref>
Line 76: Line 77:
Historically, the freckled duck has been kept with limited success in captivity and ironing out the issues with captive life is still an ongoing issue. Issues with stress, breeding and mortality rates of chicks are amongst the biggest issues with keeping these ducks in captive environments. In recent years some of these concerns have been mitigated with establishments such as the Hunter Wetlands Australia and Slimbridge Wetlands UK implementing successful breeding programs, with chicks surviving to adulthood.<ref name=:28/>
Historically, the freckled duck has been kept with limited success in captivity and ironing out the issues with captive life is still an ongoing issue. Issues with stress, breeding and mortality rates of chicks are amongst the biggest issues with keeping these ducks in captive environments. In recent years some of these concerns have been mitigated with establishments such as the Hunter Wetlands Australia and Slimbridge Wetlands UK implementing successful breeding programs, with chicks surviving to adulthood.<ref name=:28/>


The freckled duck is a highly compatible species, with various establishments holding this species in groups of various sizes, sex ratios and species with no interspecific or intraspecific aggression. However, there has been limited success with breeding programs when housed in mixed exhibits.<ref name=:3>{{cite journal|last1=Briggs|first1=S. V.|last2=Hodgson|first2=P. F.|last3=Ewin|first3=P.|year=1994|title=Changes in populations of waterbirds on a wetland following water storage|journal=Wetlands (Australia)|volume=13|issue=2|pages=36–48}}</ref>
The freckled duck is a highly compatible species, with various establishments holding this species in groups of various sizes, sex ratios and species with no interspecific or intraspecific aggression. However, there has been limited success with breeding programs when housed in mixed exhibits.<ref name=:3>{{cite journal|last1=Briggs|first1=S. V.|last2=Hodgson|first2=P. F.|last3=Ewin|first3=P.|year=1994|title=Changes in populations of waterbirds on a wetland following water storage|journal= Wetlands Australia|volume=13|issue=2|pages=36–48|doi=10.31646/wa.161|doi-access=free}}</ref>


Behavioural considerations are another consideration to take into account when holding a captive population of freckled ducks. The most important of these considerations is the possibility of imprinting on a subject other than the mother. [[Genomic imprinting|Imprinting]] is an instinctual phenomenon that occurs early on in life whereby the juvenile establishes a long lasting behavioural response to the parent (or another animal, person or thing that is present during the crucial imprinting period).<ref name=:17>{{cite journal|last=Hess|first=E. H.|year=1958|journal=Scientific American|title=Imprinting in animals|volume=198|issue=3|pages=81–90}}</ref> Imprinting on human keepers is a serious consideration, as hatchlings require the mother to learn important behaviour traits—including vocalisations, feeding, and other important attributes.
Behavioural considerations are another consideration to take into account when holding a captive population of freckled ducks. The most important of these considerations is the possibility of imprinting on a subject other than the mother. [[Genomic imprinting|Imprinting]] is an instinctual phenomenon that occurs early on in life whereby the juvenile establishes a long lasting behavioural response to the parent (or another animal, person or thing that is present during the crucial imprinting period).<ref name=:17>{{cite journal|last=Hess|first=E. H.|year=1958|journal=Scientific American|title=Imprinting in animals|volume=198|issue=3|pages=81–90|doi=10.1038/scientificamerican0358-81|bibcode=1958SciAm.198c..81H}}</ref> Imprinting on human keepers is a serious consideration, as hatchlings require the mother to learn important behaviour traits—including vocalisations, feeding, and other important attributes.


==Conservation==
==Conservation==
The species is currently classified as [[least-concern species|Least Concern]] by the [[IUCN]]. Population numbers show no definite trend, but appear to be fluctuating quite strongly, with an assessment in 2016 of 7,300 - 17,000 mature individuals. Threats include misindentification of this protected species as a game bird and consequent shooting by hunters. The ongoing destruction of swamp habitat by water diversion schemes is thought to have the capacity to result in a population decline of up to 20% within the next 15 years.<ref name=IUCN/>
The species is currently classified as [[least-concern species|Least Concern]] by the [[IUCN]]. Population numbers show no definite trend, but appear to be fluctuating quite strongly, with an assessment in 2016 of 7,300 - 17,000 mature individuals. Threats include misidentification of this protected species as a game bird and consequent shooting by hunters. The ongoing destruction of swamp habitat by water diversion schemes is thought to have the capacity to result in a population decline of up to 20% within the next 15 years.<ref name="iucn status 19 November 2021" />


==References==
==References==
{{Commonscat|Stictonetta naevosa}}
{{reflist|30em}}
{{Wikispecies|Stictonetta naevosa}}
{{Reflist|30em}}


{{Odontoanserae|B.|state=collapsed}}
==External links==
{{Taxonbar|from=Q382321}}
{{commons-inline|Stictonetta naevosa|''Stictonetta naevosa''}}


{{taxonbar}}

{{DEFAULTSORT:duck, freckled}}
[[Category:Anatidae|freckled duck]]
[[Category:Anatidae|freckled duck]]
[[Category:Ducks|freckled duck]]
[[Category:Ducks|freckled duck]]
[[Category:Birds of Australia]]
[[Category:Endemic birds of Australia]]
[[Category:Endemic birds of Australia]]
[[Category:Birds described in 1841|freckled duck]]
[[Category:Birds described in 1841|freckled duck]]

Latest revision as of 17:05, 21 January 2024

Freckled duck
Male
Female
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Subfamily: Stictonettinae
Boetticher, 1950
Genus: Stictonetta
Reichenbach, 1853
Species:
S. naevosa
Binomial name
Stictonetta naevosa
(Gould, 1841)

The freckled duck (Stictonetta naevosa) is a waterfowl species endemic to Australia. The freckled duck has also been referred to as the monkey duck or oatmeal duck.[2] These birds are usually present in mainland Australia, but disperse to coastal and subcostal wetlands in the dry period. During such times it is common for the freckled duck population to congregate in flocks in the same area, giving the impression that they are more common than they really are.[3]

The freckled duck population is at risk of further reduction from habitat destruction, droughts and game hunting. Often habitat destruction and drought can lead to an increase in hunting, as the freckled duck is forced to disperse into more coastal ranges where they may not be recognised as a protected species.[4]

In the past few decades, several institutions have established breeding programs to aid in supplementation of the freckled duck population. Such establishments included, but are not restricted to the Hunter Wetlands Centre Australia,[5] Slimbridge Wetlands, Melbourne Zoo, Bronx Zoo, Adelaide Zoo, Healesville Sanctuary, and Tidbinbilla Nature Reserve.[6] The success of these institutes has been variable, with some failing to establish self-maintaining colonies.

Description

[edit]

The freckled duck has a distinctive appearance. It is characterised, in adults, by dark grey to black plumage covered with small white flecks, which gives the duck the 'freckled' look. The feet, legs and bill of both sexes is of a slate grey colour. Hatchlings and juveniles are distinguished by a uniform light grey plumage, which they lose around their 32nd week when they undergo a full body moult to assume the adult plumage.[7]

The adult freckled duck is sexually dimorphic. On average, males are the larger sex, with average weight between 700 - 1200 g. Females have an only slightly lower range between 600 – 1200 g. Both sexes have a length of 50 – 60 cm. During the breeding season particularly, the males are characterised by the base of their culmen, which takes on various shades of red. Those in prime reproductive condition take on a deep red colouring, while other males may only develop lighter shades of red, or in some instances, no colouring at all. Deep red colouring of the culmen is also associated with dominance, and those with the deepest red are those likely to breed with the females of the group.[6]

Distribution and habitat

[edit]
Female at Sylvan Heights Waterfowl Park in Scotland Neck, North Carolina

Endemic to Australia, the freckled duck is mainly situated throughout inland regions of the Eastern section of the country—including New South Wales, Victoria and Queensland. This species also has known populations in South Australia and Western Australia.[8] Due to habitat requirements, distribution of the freckled duck directly correlates to water flow and rainfall in river catchments and wetland systems.[9] Because of this, main populations of this species are located within the Paroo-Warrego catchment (Currawinya Lakes), Eyre-Georgine-Mulligan catchment (Lake Torquinie), and potentially at Lake Galilee. High numbers have also been recorded at the Cooper's Creek catchment, wetlands within the Barkley Tablelands, the Bulloo River catchment and Lake Gregory in central north Western Australia.[8]

Freckled duck habitat preference can be split into two distinct categories: breeding and non-breeding habitat. While this species does not appear to have any sort of distinct migratory pathway or seasonal migration to find suitable breeding habitat.[10] The freckled duck sometimes travels long distances to find a suitable breeding location, and seems to prefer large bodies of fresh water with thick vegetation. Usual contenders are recently flooded wetland systems and swamps.[9] After breeding, the freckled duck disperses to more coastal areas with more permanent bodies of water such as lakes, reservoirs, and ponds. These areas are often more exposed and contain little vegetation.[11]

Ecology

[edit]

Diet

[edit]

The diet of the freckled duck has been subjected to a degree of controversy and disagreement over the years, potentially due to the versatile diet of different populations and distributions of this duck. Despite this, it is widely agreed that the freckled duck is a resilient, specialist filter feeder that consumes a range of aquatic vegetation, insects, algae, larvae and crustaceans.[12][13] Studies have found that the freckled duck prefers to feed in shallow water, using its bill to strain food particles from the mud or sand.[14]

Social behaviour

[edit]
Illustration from The Birds of Australia (1890) (with Pacific black duck)

A highly gregarious species, the freckled duck is known to have flock sizes ranging from 10 to 100 individuals, especially outside of breeding season. During breeding season, these flocks often break up into smaller sub-units, scattered throughout wetland and swamp systems.[15]

Despite these large flock sizes, this species is lacking in demonstrative displays towards one another, with only cryptic gestures and few interactions towards fellow flock mates. The rare interaction that is observed within this species is usually of a quarrelsome nature.[16]

Bathing

[edit]

While there has been little research into the bathing behaviour of the freckled duck, it is known that a body of water (e.g. a swamp or dam) is essential for many natural behaviours such as feeding, mating and bathing.[17] Freckled ducks have been observes preening both within water and after emerging from water while in a roosting position.[18] There is no evidence that the freckled duck dust bathes or requires any other substrate for bathing.

Reproductive behaviour

[edit]

The freckled duck is a polygamous species that undertakes short term, seasonal monogamous pairings in the wild. In this short term pairing, the male defends the receptive female during the pre-egg laying stage of the breeding season. During this time, the male also helps construct and defend the nest site—but leaves before the female lays her clutch, and plays no further role in rearing or defending his offspring.

The freckled duck has few pre or post copulatory behaviours. Copulation occurs in the water with the male approaching a receptive female, who adopts a semi-submerged orientation, with her head stretched outwards and tail raised. The male then mounts the female and clutches the feathers on the lower neck of the female during copulation. After dismounting, both sexes display bathing and preening behaviours.

The breeding season of the freckled duck is basically regular, with a generic breeding season between September and December. However, it retains the ability to breed out of season. Breeding out of season highly correlates with periods of heavy rainfall and flooding.

Chick at Sylvan Heights Waterfowl Park in Scotland Neck, North Carolina

Both male and female freckled ducks reach sexual maturity at around 12 months of ages when the first breeding occurrence can commence. The freckled duck has been known to continue breeding annually throughout their life, with records suggesting successful breeding in birds in excess to 10 years of age.[6]

The freckled duck has a standard incubation period of between 26 and 28 days, though some sources have recorded incubation periods of up to 35 days. The female is solely responsible for egg incubation and only leaves the eggs for short periods to feed.

The average clutch is seven eggs, but can range between four and 14 eggs.[19] Clutches of up to 14 eggs can occur naturally, though this occurrence mainly appears to be the result of females 'dumping' additional eggs into another female's nest. This occurrence is common within freckled duck populations as it enables the offending females to pass on their genetic material while not expending energy to raise their hatchlings.[20]

The eggs of the freckled duck are glossy, smooth and almost perfectly oval in shape. They are white in colour, ranging from shades of cream to ivory. The freckled duck egg is unique, having an exceptionally thick but soft shell unlike that of any other species. Egg measurements usually fall between 60-65mm by 45-48mm and weigh an average of 66g.[21]

Freckled duck hatchlings are precocial, meaning they hatch fully functional and able to feed themselves. Despite this, they still need their mother for the best chance of survival. Apart from protection, the hatchlings need the mother to teach them important social cues and behaviours.[22]

The ducklings fledge late compared with other waterfowl species, at nine weeks, when they no longer need their mother's protection. At this point, the mother and fledglings are likely to re-join a larger flock.(Flinchum, 2005)

In captivity

[edit]

Historically, the freckled duck has been kept with limited success in captivity and ironing out the issues with captive life is still an ongoing issue. Issues with stress, breeding and mortality rates of chicks are amongst the biggest issues with keeping these ducks in captive environments. In recent years some of these concerns have been mitigated with establishments such as the Hunter Wetlands Australia and Slimbridge Wetlands UK implementing successful breeding programs, with chicks surviving to adulthood.[6]

The freckled duck is a highly compatible species, with various establishments holding this species in groups of various sizes, sex ratios and species with no interspecific or intraspecific aggression. However, there has been limited success with breeding programs when housed in mixed exhibits.[23]

Behavioural considerations are another consideration to take into account when holding a captive population of freckled ducks. The most important of these considerations is the possibility of imprinting on a subject other than the mother. Imprinting is an instinctual phenomenon that occurs early on in life whereby the juvenile establishes a long lasting behavioural response to the parent (or another animal, person or thing that is present during the crucial imprinting period).[24] Imprinting on human keepers is a serious consideration, as hatchlings require the mother to learn important behaviour traits—including vocalisations, feeding, and other important attributes.

Conservation

[edit]

The species is currently classified as Least Concern by the IUCN. Population numbers show no definite trend, but appear to be fluctuating quite strongly, with an assessment in 2016 of 7,300 - 17,000 mature individuals. Threats include misidentification of this protected species as a game bird and consequent shooting by hunters. The ongoing destruction of swamp habitat by water diversion schemes is thought to have the capacity to result in a population decline of up to 20% within the next 15 years.[1]

References

[edit]
  1. ^ a b BirdLife International (2016). "Stictonetta naevosa". IUCN Red List of Threatened Species. 2016: e.T22679836A92831716. doi:10.2305/IUCN.UK.2016-3.RLTS.T22679836A92831716.en. Retrieved 19 November 2021.
  2. ^ Johnsgard, P. A. (2010). "Tribe Stictonettini (Freckled Duck)". Ducks, Geese, and Swans of the World. pp. 97–100.
  3. ^ Garnett, S. (1992). The Action Plan for Australian Birds (Report). Canberra: Australian National Parks and Wildlife Service.
  4. ^ Loyn, R. H. (1991). "Assessing and managing the impact of duck hunting in Victoria - a new approach". Wildfowl. 42: 155–161.
  5. ^ "Frecked Ducks in Residence". Hunter Wetlands Centre Australia. Retrieved 13 May 2023.
  6. ^ a b c d Wilson, S.; Silcocks, S. (2001). "The husbandry and breeding of the freckled duck at Melbourne Zoo". Australian Birdkeeper. 14 (9): 524–527.
  7. ^ Norman, F. I.; Norris, K. C. (1982). "Some notes on Freckled Duck shot in Victoria, Australia, 1981". Wildfowl. 33: 81–87.
  8. ^ a b Maher, M. T.; Braithwaite, L. W. (1992). "Patterns of waterbird use in wetlands of the Paroo, A river system of inland Australia". The Rangeland Journal. 14 (2): 128–142. doi:10.1071/rj9920128.
  9. ^ a b "Freckled Duck (Stictonetta naevosa)". Department of Environment and Heritage NSW. 2016.
  10. ^ Blakers, M.; Davies, S.; Reilly, P. N. (1984). The Atlas of Australian Birds. Melbourne: Melbourne University Press.
  11. ^ Martindale, J. (1986). The Freckled Duck. Moonee Ponds, Victoria: Royal Australasian Ornithologists' Union.
  12. ^ Norman, F. I.; Brown, R. S. (1985). "Gizzard grit in some Australian waterfowl". Wildfowl. 36: 77–80.
  13. ^ Corrick, A. H. (1980). "Freckled Ducks on lakes in the Western District, Victoria". Australian Bird Watcher. 8 (1): 254–255.
  14. ^ Crome, F. H. (1985). "An Experimental Investigation of Filter-Feeding on Zooplankton by Some Specialized Waterfowl". Australian Journal of Zoology. 33 (6): 849–862. doi:10.1071/zo9850849.
  15. ^ Craig, M. (1994). Captive species management plan for freckled duck: Stictonetta naevosa (Report). Parkville, Victoria: Zoological Board of Victoria.
  16. ^ Fullagar, P. J.; Davey, C. C.; Rushton, D. K. (1990). "Social behaviour of the Freckled Duck Stictonetta naevosa with particular reference to the Axle-grind". Wildfowl. 41: 53–61.
  17. ^ Braithwaite, L. W. (1976). "Notes on the breeding of the Freckled Duck in the Lachlan River Valley". Emu. 76 (3): 127–132. doi:10.1071/mu9760127.
  18. ^ Frith, H. J. (1964). "The downy young of the Freckled Duck, Stictonetta naevosa". Emu. 64 (1): 42–47. doi:10.1071/mu964042.
  19. ^ Briggs, S. V. (1982). "Food habits of the Freckled Duck and associated waterfowl in North-western New South Wales". Wildfowl. 33: 88–93.
  20. ^ Jaensch, R. (2003). "Breeding by freckled Duck Stictonetta naevosa in the Diamantina Channel Country". Sunbird: The Journal of the Queensland Ornithological Society. 33 (1): 24–28.
  21. ^ Frith, H. K. (1965). "Ecology of the Freckled Duck Stichonetta naevosa (Gould)". CSIRO Wildlife Research. 10 (1): 125–139. doi:10.1071/cwr9650125.
  22. ^ Kear, J. (2005). Ducks, Geese and Swans. Vol. 2: Species Accounts (Cairina to Mergus). Oxford: Oxford University Press.
  23. ^ Briggs, S. V.; Hodgson, P. F.; Ewin, P. (1994). "Changes in populations of waterbirds on a wetland following water storage". Wetlands Australia. 13 (2): 36–48. doi:10.31646/wa.161.
  24. ^ Hess, E. H. (1958). "Imprinting in animals". Scientific American. 198 (3): 81–90. Bibcode:1958SciAm.198c..81H. doi:10.1038/scientificamerican0358-81.