Species Update
Milder winters across the world mean fewer Mallards migrating to the UK during the colder months, says Kate
Kate Risely on the Mallard – a familiar bird that can pose an identification challenge
Their adaptability means it’s surprisingly hard to get a handle on how many breeding Mallards might be dispersed across different habitats
DESPITE BEING ONE of our most familiar birds, common or garden Mallards can occasionally pose an identification challenge. For generations, this species has been bred into an array of domesticated strains, which, as well as being different colours, can be much larger or smaller than true wild Mallards. Escapees will freely mingle and interbreed with their natural cousins, and this mixed stock can lead to wild ducks displaying odd characteristics, occasionally catching out beginner birdwatchers. In their wild form, drake Mallards are unmistakable, and, being both adaptable and habituated to humans, they are found in nearly all areas and habitats across Britain and Ireland, absent only from remote mountainous regions. They are comfortable in suburban and even urban areas and may live their whole lives in towns and cities, breeding in gardens and inhabiting ponds and other water bodies. They nest on the ground, sometimes even in garden flowerbeds; a nest of up to 14 large duck eggs may sound conspicuous, but they rely on camouflage and concealment as their defence from predators, and nesting females may go unnoticed. After the eggs have been incubated for about a month, the ducklings will hatch, and they can immediately forage for themselves. Their mother will lead them to the nearest water to find food, and for some protection from land predators, though in urban areas they may have to negotiate traffic and other perils on their way to the relative safety of the water. As well as being domesticated for meat and eggs, Mallards also have a long history as a quarry species, and were originally caught using duck decoys. These were a major industry in the 17th and 18th Centuries, mainly in eastern areas of England, and worked by luring birds to land on an inviting pond, often through the presence of tame birds, and then funnelling them into cages. Rather than attempting to herd the ducks into the cages from behind, the trappers exploited an odd aspect of duck psychology that compels them to band together and walk towards a predator, perhaps in order to keep visual contact and prevent themselves being ambushed. The trappers would use specially trained dogs to run alongside the fences and lure the birds into the funnels. This hunting method died out with the rise of shooting, but is still used today in some areas to catch wildfowl for ringing. It’s always tricky to estimate actual numbers of very common bird species, and their adaptability means it’s surprisingly hard to get a handle on how many breeding Mallards might be dispersed across different habitats. Their national population is very broadly estimated at between 60,000 and 150,000 breeding pairs, and the wintering numbers at around 700,000 individuals, but these figures are thought to be pretty unreliable. The breeding population is regularly supplemented by captive-bred birds for shooting purposes, and has increased steadily from the 1960s to the 2000s, though numbers have remained stable for the last 20 years. On the other hand, wintering numbers, monitored for decades by the Wetland Bird Survey, have been declining since the 1980s. It is now an Amber Listed species of conservation concern. Mallards arrive here for the winter from northerly areas including continental Europe, Scandinavia and Russia. It’s thought that the decline in wintering numbers seen in this country could be due to the generally milder winters in recent years, meaning that fewer birds are driven to migrate.