Ducks

By Helena Phimister

Habitat

Different species of ducks are spread throughout most of the world except for Antarctica. Many species adapted to live on sub-Antarctic islands like South Georgia and Auckland Islands. Oceanic Islands like Hawaii, New Zealand and Kerguelen have a numerous amount of ducks that have estaplished themselves there. However on a sad note most of the species are threatened or have become extinct.
When breeding in temperate and Arctic Northern Hemisphere, some species of duck are migratory. others in the tropics are generally not. In Australia  the rainfall is patchy, the ducks are nomadic, the seek temporary lakes that form after the rain.

Fertilisation

Ducks carry their eggs and wait until a 'worthy' drake comes along to fertilise the eggs. By worthy I mean; the duck may choose a specific drake to be the father of their ducklings. If a duck gets 'raped' she can confuse the drake by closing off passages and leading his penis (sperm) away from her eggs, therefore the drake is very confused and leaves. When the drake that the duck wants to fertilise her eggs she leads his penis (sperm) to the eggs.Ducks carry a fare few eggs to be fertilised so when the drake's penis reaches the 'nest' where the eggs are kept he releases just enough sperm to fertilise each individual egg.
As explained above, ducks and drakes reproduce by cross-fertilisation and the eggs are fertilised internally, inside the duck. Depending on how many duck gametes will result in how many drake gametes are used, e.g. there are 5 eggs to fertilise (5 duck gametes) and 5 sperm are used (5 drake gametes). This fertilisation is good in the way that no unwanted sperm are wasted, the duck chooses her drake and the duck's complex 'maze' to her eggs means she can lead the drake to the eggs or confuse the drake away from her eggs. A disadvantage is the drake the duck chose may have a disease that has a 50% chance of being given to the ducklings.

Development

The duck gathers reeds and twigs to make a nest on the edge of the pond, so that it is surrounded resulting in no predators stealing the unhatched ducklings. to make it more comfy she uses her feathers. She 'poops' the eggs out at sits on them to keep them warm. The eggs develop externally in the way that they are no longer inside the duck but develop internally because they are in an egg. this type of egg is an amniote as it has a shell.

Parental Care

When the ducklings emerge from their egg they imprint on the first duck/drake they see which is usually their mother. This is the reason for them following their mother around where ever she goes thy go. If when the ducklings are born and they are physically stuck in an area that they cannot get out of, the mother will never abandon them. The only reason for an orphan duckling is if it hatched late and the mother and its brothers and sisters have already moved on.

Interesting  Facts

  • The females are called ducks.
  • The males are called drakes.
  • Their babies are called ducklings.

Bibliography

  ABC. (2013). Creature
  Features, Pet Facts, Ducks
. Retrieved September 15th, 2013, from ABC:
  http://www.abc.net.au/creaturefeatures/facts/ducks.htm
  Wikipedia. (2013, August 6th). Duck. Retrieved September 12th, 15th, 16th, 2013, from
  Wikipedia: http://en.wikipedia.org/wiki/Duck

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