THE WORLD BIRDS - An Online Bird Book
The term waterfowl is used to describe any member of the order Anseriformes. A series of articles describes all the waterfowl. This specific article describes the
"screamers and magpie goose" which belong to family Anhimidae and family Anseranatidae respectively.
Anseriformes
Most species of the order Anseriformes spend a considerable amount of time in water. In fact, they are called waterfowls. Their webbed feet make for efficient swimming. A few species spend little time in water and thus their feet are only partially webbed. Most waterfowl are also good flyers, many migrating long distances to escape the cold and others migrating shorter distances for optimizing their food supply. All species, except the screamers, have a wide and relatively flat bill. The shape of a species bill and also their tongue is a function of their diet. Considering the entire order, they eat aquatic plants, grasses, sedges, algae, plankton, insects, insect larvae, mollusks, crustaceans, fish, fruits, grains, rice. Most species are monogamous and if they lose a partner seem to mourn. Males are larger and heavier than females. The chicks are well developed when they hatch and can walk almost immediately.
Family Anhimidae - Screamers
Family Anhimidae
The screamers are a small family of birds related to ducks (family
Anatidae), but more closely to the magpie goose which is the only species in family
Anseranatidae. The three
Anhimidae species
occur only in
South America,
ranging from Venezuela to northern Argentina. They are so named for their loud calls. They are large, bulky birds, with a small downy head, long legs and large feet which are only slightly webbed. In fact, the screamers have the least webbing on their feet of any members of Anseriformes. Their bill is more like that of a chicken or hawk than it is duck-like. They have large spurs on their wings which
are used in fights over mates and territorial dispute]; these can break off in the breast of other screamers, and are regularly renewed. Unlike ducks, they have a partial moult, and are able to fly throughout
the year. The young, like those of most Anseriformes, can run as soon as they are hatched. They live in open areas and marshes with some grass and feed on water plants. The southern screamer is often kept as a guard animal because of its loud call, it is not a fussy eater, and it imprints on its caregiver at birth.
Genus Anhima - 1 species
Screamer, Horned Anhima cornuta
Image by: 1)
Diego Miguel_Garces 2) Bradley_Hacke in Peru 3)
Cláudio Timm - the Amazon, Brazil
Genus Chauna
Screamer, Northern Chauna chavaria
Image by: 1)
Petruss - Columbia 2)
Nick Athanas - Columbia 3)
anthrotect
Screamer, Southern Chauna torquata
Image by: 1 )
Dick Daniels -
Jacksonville Zoo 2, 3) Cláudio Timm - - Tacuarembó,
Uruguay 4) Dick - San Diego Zoo 5) Cristiano Crolle -
The magpie goose is the only species in family
Anseranatidae. This family belongs to order
Anseriformes which is the same order as family
Anhimidae (the 3 screamers) and family
Anatidae: ducks, geese, and swans. The family is quite old. It probably existed before the extinction event that ended the rule of the dinosaurs about 6 6 million years ago. It evolutionary path diverged from a common ancestor after the screamer family, but before the ducks, goose and swan family.
Genus Anseranas - 1 species
The magpie goose diverged from the other waterfowl tens of millions of years ago, but it does have the general look of a goose. With its black and white plumage is aptly named.
Goose,_Magpie Anseranas semipalmata
Image by: 1)
Dick Daniels - Australia 2)
JJ Harrison - Northern Territory, Australia. 3)
Geoff_Whalan - North West Territory 4)
David_Cook - Northern Territory 5)
Dick - Sylvan Heights
5) Partially webbed feet