Diving ducks

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Diving ducks
Male pochard

Male pochard

Systematics
Class : Birds (aves)
Order : Goose birds (Anseriformes)
Family : Duck birds (Anatidae)
Subfamily : Anatinae
Tribe : Diving ducks
Scientific name
Aythyini
Delacour & Mayr , 1945

The diving ducks (Aythyini) are a tribe of the duck birds (Anatidae). They are especially widespread in freshwater habitats in the northern hemisphere and, in contrast to the swimming ducks , they reach their food by diving to the bottom of the water.

features

The diving ducks look for their food while diving or swimming underwater. This is why their bodies are more compact and their necks shorter than those of the swimming ducks. Diving ducks have little buoyancy to make diving easier and are therefore quite deep in the water. Her large feet also set far behind the body. Diving ducks find it relatively difficult to fly out of the water, which is why they have to make an appropriate approach. Even so, they are very good fliers.

Although the males are often brightly colored, their plumage is not as magnificent and bright as that of many swimming ducks. There is also a clear sexual dimorphism in diving ducks : females are always more inconspicuously colored than males. The diving ducks lack the wing mirror characteristic of swimming ducks .

distribution and habitat

Diving ducks inhabit freshwater habitats. With a few exceptions, they can never be found on the coast of the sea. Since they reach their food by diving, they also inhabit deeper waters, which are unsuitable for the swimming ducks that swim in the ground. The distribution area includes all continents except Antarctica. The greatest biodiversity, however, is found in the northern hemisphere, especially in North America.

Way of life

The food mainly consists of parts of plants, as well as invertebrates such as aquatic insects, crustaceans and mollusks . Some species feed almost exclusively on plants, but with the tufted duck and the mountain duck there are also species that eat animal food almost exclusively. Although diving ducks' food is mostly captured by diving, they can also scoop in shallow water like swimming ducks. At greater depths, the tactile sensory cells on the beak are used to track down the prey, since the eyes are useless here.

An average dive lasts 30 seconds, but no longer than 60 seconds. The preferred diving depth is 1 to 3 m. In tufted ducks, maximum diving depths of 7 m were found.

Like swimming ducks, diving ducks are monogamous, but only for one breeding season. Before the young hatch, the couples separate again.

Systematics

The sister group of diving ducks are the swimming ducks, to which they resemble in many ways. The marble duck is a species that zoologists do not always agree on whether it is a swimming duck or a diving duck, as it has characteristics of both tribes. Kear includes the following species among diving ducks:

literature