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The avian family Anatidae, commonly called waterfowl, comprise the ducks, geese, and swans.The International Ornithological Committee (IOC) recognizes these 174 Anatidae species distributed among 53 genera, 32 of which have only one species.
The word duck comes from Old English dūce 'diver', a derivative of the verb *dūcan 'to duck, bend down low as if to get under something, or dive', because of the way many species in the dabbling duck group feed by upending; compare with Dutch duiken and German tauchen 'to dive'.
About one half of bird species with fovea have a single one, but uniquely in birds, [221] some, such as terns, kingfishers and hummingbirds, have a second fovea, [222] called the temporal fovea, that assists in judging speed and distance and increases visual acuity. Birds that do not have a second fovea will sometimes bob their head to improve ...
One duck serves as a sentry, watching for predators as the others in the group dive in search of food. [8] Buffleheads are amongst the last waterfowl to leave their breeding grounds and one of the world's most punctual migrants, arriving on their wintering grounds within a narrow margin of time.
The long period of evolution and shifts from one kind of waterbird lifestyle to another have obscured many plesiomorphies, while apparent apomorphies are quite often the result of parallel evolution, for example the "non-diving duck" type displayed by such unrelated genera as Dendrocygna, Amazonetta, and Cairina. For the fossil record, see below.
The diving ducks, commonly called pochards or scaups, are a category of duck which feed by diving beneath the surface of the water. They are part of Anatidae, the diverse and very large family that includes ducks, geese, and swans. The diving ducks are placed in a distinct tribe in the subfamily Anatinae, the Aythyini.
Animal identification using a means of marking is a process done to identify and track specific animals. It is done for a variety of reasons including verification of ownership, biosecurity control, and tracking for research or agricultural purposes.
At times in North America, the bands have just a unique number (without an address) that is recorded along with other identifying information on the bird. If the bird is recaptured the number on the band is recorded (along with other identifying characteristics) as a retrap. All band numbers and information on the individual birds are then ...