Growing populations mean issues for ducks.

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A female mallard.
There are many species of ducks that inhabit the UK including mallards, mandarins and long-tailed ducks. The scientific name for the mallard is Anas platrhynchos and they are in the ducks, geese and swans bird family. Their UK conservation status is amber meaning they are under concern but they are protected under The Wildlife and Countryside Act 1981. The males of the species look different to the females of the species meaning they are sexually dimorphic. Male mallards are more colourful than females and have distinctive green heads and yellow beaks. Females are all brown compared to males who have white bodies. They are usually around 60 cm in length and have a wingspan of 81-98 cm. There are between 61,000-146,000 breeding pairs in the UK.
A male mallard being followed by a female.

There is a close link between food and number of mallards. If there is a lot of food resources in a pond then there will be a lot of mallards but this can lead to overpopulation problems. If there is a very regular food supply then there will be a very high number of ducks nesting in the area. A main issue of this is that there will be many unattached males in the area which in groups forcibly mate unattached females. This can create dangerous feeding breaks as the females who are incubating are exhausted. Many young females who are breeding for the first time do die due to their first breeding experience as they are unaware of dangers and are already weaker from producing an egg. There is danger to the ducklings as many females have to nest away from the pond and this leads to danger for hatchlings as they have to make their way to the pond. Ducks become more sedentary if food sources are adequate and reliable from year to year. More droppings enter the pond due to the fact there are more ducks. This adds nutrients to the pond and therefore causes algae to grow and 'bloom' which covers aquatic plants and reduce the oxygen levels in the water. The algae is a source of botulism in hot weather and lets out toxins that affect the nervous systems of the ducks and causes them to experience respiratory failure and die.

A female mallard in flight.
During the breeding season the female is the one that builds the nests. They build their nests out of grasses of leaves as the outside and then line them with down that she plucks from her own breast. The laying period is from mid-march to late July where females usually lay a clutch of around 12 eggs, each laid one or two days apart. Each time an egg is produced, the female covers the whole clutch in order to protect her eggs from predators. During the laying period the female lays over half her own body weight in eggs and therefore needs a lot of rest so it is pretty much down to the males to protect and feed the female. After the clutch is laid the males role becomes less prominent. He stays sexually potent for a small period in time just incase the clutch needs a replacement but after awhile he looses interest and begins to moult.


A female mallard divine for food.
Almost all ducks are omnivores. To feed heavier ducks dive under the water to search for fish. Other ducks dabble. This is when they eat on the surface of the water or on land. These ducks feed on grasses, small insects and seeds.  It is a common belief that feeding ducks bread is good for them but on a large scale it can cause them dietary problems so should be avoided.

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