Where do ducks nest?
Mallards start to pair up in October and November, and begin nesting in March.
Finding a nest spot
They prefer to nest near water. Females generally make their nest in a place well covered in vegetation or in a natural hole in a tree. Mallards exploit any open water where food is plentiful, however. This sometimes results in the choice of less than perfect nest sites, particularly in towns.
Nests have been found in boathouses, wood piles, old crow's nests, hay stacks, roof gardens, enclosed courtyards and even in large flowerpots on balconies several floors up!
Town ponds with an abundant and reliable food supply often attract more mallards than are able to nest close by. In these situations, many female mallards nest well away from the pond to avoid competition and harassment from others
Encouraging and deterring nesters
Most people welcome ducks nesting in their garden. They often choose parts of a garden where the vegetation provides them enough cover in which to conceal the nest. Having a well-stocked flowerbed or shrubby border, or leaving a corner of your garden to grow wild to provide them with good nesting habitat will help encourage nesting.
The female should be able to find food for herself while she incubates, but you could put out a bowl of drinking water, together with duck pellets and cooked potatoes for her to eat. Put these in an accessible area some distance from the nest.
It is normally not practical to prevent ducks nesting in a garden. They are very secretive about a nest, so if you see a pair of ducks hanging around the chances are they're already nesting. Be aware that ducks and their nests receive legal protection across the UK, so you must allow a duck access to her nest.
If you have a pond but do not want it to attract nesting ducks into your garden, make sure you cover the pond before the breeding season starts. Although ducks may still nest, without access to water, they will be less likely to stay in the garden after the ducklings hatch.
The female mallard builds a nest from leaves and grasses and lines it with down plucked from her breast.
Eggs are laid between mid-March and the end of July. The normal clutch is about 12 eggs, laid at one to two day intervals. After each egg is added, the clutch is covered to protect it from predators. If you find a nest full of duck eggs, leave it well alone – it is unlikely to have been abandoned.
The laying period is very stressful for the female – she lays more than half her body weight in eggs in a couple of weeks. She needs a lot of rest and depends heavily on her mate to protect her and their feeding and loafing areas.
End of the pair bond
The role of the male is almost over once the clutch is laid. He remains sexually potent for a while in case a replacement clutch is needed, but gradually loses interest and joins other males to moult. At this time, groups of males with no obvious duties often mate forcibly with females that appear to be unattached. This anti-social phase is short-lived and ends once moulting is underway.
Mallards and the law
Wild birds and their nests are protected by the Wildlife and Countryside Act 1981 in England, Scotland and Wales, which includes that it is an offence to intentionally (or recklessly in Scotland) kill, injure or take any wild bird, or to take, damage or destroy (or otherwise interfere with in Scotland) its nest, eggs or young.
This includes mallards and other wildfowl, but these can also be legally shot during open seasons, subject to certain legal provisions.
The open season for mallards is normally from 1 September - 31 January, with an extension which applies below the high water mark of ordinary spring tides on the coast in England, Wales and Scotland until 20 February. Northern Ireland has its own legislation.
During the breeding season, it is important not to chase away a duck that has started nesting since she must be allowed access to her nest. If you find a nest full of eggs, you must not interfere with them. In some parts of the UK under certain circumstances those managing a site may be authorised to remove eggs to rear in captivity and then release, or to destroy (but not keep) eggs from a failed nest later in the year.
Further advice should be sought from the relevant conservation Authority by anyone who is unsure of the laws which apply to their situation.
Find out more information about mallard ducklings, from hatching out of the egg until they are fledged.