MALLARD
Taxonomy
Latin name-Anas platyrhynchos
English name-Mallard
Class-Birds (Aves)
Order-Geese (Anseriformes)
Family-Duck (Anatidae)
Genus-River ducks (Anas)
There are 3 main subspecies: A. p. platyrhynchos, A. p. conboschas, and A. p. diazi.
The first scientific description of mallard was made by Carl Linnaeus in 1758. However, Linnaeus made a mistake and attributed the male and female mallards to different species.
Environmental status
According to the international status, the mallard belongs to the species whose existence causes the least concern - IUCN (LC). The global mallard population is estimated at 2-2. 5 million pairs.
Species and person
Mallard is an object of sports, and sometimes commercial hunting. Duck hunting with a dog, with a decoy, autumn is described by many classics of Russian literature. Since drakes are most often shot, properly organized hunting does not cause much harm to the mallard population.
In the autumn, the fields of cereals located near the reservoirs where flocks of ducks gather for rest, cause significant damage, as mallards willingly feed on the seeds of cereals. At the same time, they also bring benefits, since they destroy insect pests and weed seeds.
Mallard is the ancestor of many breeds of domestic ducks, there is even a special subspecies of A. p. domesticus-domestic duck. According to some sources, the domestication of ducks occurred in Mesopotamia 5000 years ago; according to others-much earlier, 1000 years BC, and in Europe, Asia, North Africa and North America at the same time.
Currently, many breeds of domestic ducks have retained the color of their wild ancestors and are anatomically no different from them, only they have become larger and clumsier. All breeds of domestic ducks easily cross each other and give fertile offspring. Wild mallards are still easily domesticated.
In large cities, including Moscow, populations of wintering mallards have formed, which are regularly fed by people. These ducks are kept on many urban reservoirs (large and small rivers, ponds, lakes), and in winter they concentrate on those that do not freeze. In the summer, they can feed themselves, although they still actively beg. In the summer, they even bring some benefits-they eat duckweed and mosquito larvae. In winter, they can not exist without feeding people. Every year, 28,000-30,000 mallards winter in Moscow.
Distribution and habitat
Mallard is widely distributed in the northern hemisphere. It breeds both in northern latitudes to the north up to 700 s. s., and in warm subtropical climates up to 350 s. s. in North Africa and up to 200 s. s. in the Middle East. The nominal subspecies A. p.platyrhynchos lives in the greater part of the range, the subspecies A. p.diazi lives in the New World (Mexico and the adjacent states of the USA), and A. p.conboschas lives in Greenland.
Outside of its natural range, the mallard is found in New Zealand and South-Eastern Australia, where it was introduced by immigrants from Europe and is now considered an alien species that violates the integrity of the local fauna.
In choosing a habitat, the mallard is quite unpretentious. It lives in the forest zone and in the forest-steppe, where it is numerous, but becomes rare at the northern borders of woody vegetation, in the mountains and deserts. It inhabits a wide variety of reservoirs with fresh, brackish and salt water, but avoids rivers and streams with a fast current. During the breeding season, it prefers inland freshwater reservoirs with high herbaceous vegetation.
On the southern border of its range, it breeds exclusively in the mountains – in northern Africa up to 2000 m above sea level, in the Himalayas - up to 1000 m above sea level.
Appearance
Mallard-a fairly large squat duck with a large head, short legs with swimming webs and a short tail. Body length 51-62 cm, wingspan 80-100 cm, wing length 27.5-30.6 cm for males, 25.2 – 28.5 cm for females, weight 0.75-1.5 kg. The bill is broad and flat with a well-developed crest of horn plates at the edges.
Like most duck species, mallards have a distinct sexual dimorphism (the difference in color between males and females), especially noticeable in late winter and spring, when the ducks form pairs. The male is much more brightly colored than the female. Drakes in mating dress have a shiny dark green head and neck, bright purple "mirrors" on the wings, the size of which increases with the age of the bird. There is a black curl on the tail, formed by secondary tail feathers. The main background of the operculum is brownish-gray. After the summer molt, the males lose their bright features and become similar to the females. Females are always painted in a modest grayish-brown color. Sexual differences are also observed in the color of the beak. In males in the mating dress, it is ochre-olive or almost yellow, in females it varies from dark olive to dark gray with orange edges. There are always a few small black spots at the base of the female's beak.
The legs of mallards of both sexes are orange-red with darker webbing.
Lifestyle and social behavior
Usually mallards are kept alone, in pairs or in flocks on the water or near reservoirs. The flight is fast, very noisy, the flapping of the wings is accompanied by a special sound. They rise relatively easily from the water. Only wounded mallards dive, in this case they can swim several tens of meters under water. They waddle along the ground.
Mallard is a partially migratory species. Most of the ducks that nest in northwestern Russia, Finland, Sweden, and the Baltic States move to the coast of Western Europe. In warm years, they also remain to winter in the nesting areas. In the rest of Europe, mallards are sedentary. From Western Siberia, mallards winter in a variety of regions-from the Balkan Peninsula in the west to the Caspian Lowland in the east. Birds that nest in northeast Asia and the Far East, winter on the Japanese Islands. Mallards that nest in the mountains make vertical seasonal migrations, descending to lowland areas for the winter.
Outside of the breeding season – on molting, on flight and in wintering areas, mallards keep flocks, the size of which can vary from a few birds to several hundred or even thousands of individuals.
In large cities, including Moscow, a special population of urbanized ducks has formed. At one time, it was even believed that the birds in these populations became larger and heavier than their migratory relatives, but later this assumption was not confirmed. The emergence of such sedentary urban populations is associated with the presence of non-freezing reservoirs, the feeding of birds by humans, and the absence of many natural enemies.
Mallards tend to have 2 seasonal molts – full at the end of the nesting season and partial-before it begins. The complete change of plumage of the males begins when the females begin to incubate the clutch, and the females-when the brood rises to the wing. Most molting males gather in single-sex flocks at the end of May and fly away to molt, while others remain to molt in nesting sites. The total duration of molting is about 2 months. The period when the flight feathers fall out, and the birds lose their ability to fly, lasts 20-25 days. Molting birds spend the day in the thickets of aquatic vegetation, and in the evening they swim out to feed on open water.
Vocalization
The most famous sounds made by a mallard are quiet quacking (hence the name). However, these ducks can make other sounds depending on the sex, period in life, and condition of the birds. For example, the" conversation " of a female with ducklings and the voice of a male during the mating period differ significantly in volume, tonality and sound. Males during courtship emit a high hoarse whistle with the help of a special bone formation in the lower part of the trachea. When frightened, the quacking becomes more prolonged, and when flying – quiet and hurried.
Nutrition and feeding behavior
According to the nature of the diet, the mallard can be attributed to an omnivorous species, its diet contains both plant and animal feed, depending on the place and season. In the choice of feed, mallards are very flexible and easily adapt to the conditions of a certain area.
They usually feed in shallow water, at a depth of 30-35 cm, straining through the horn plates on the beak of small aquatic animals and plant food. Among the plant feeds are duckweed, green parts of aquatic plants, underwater tubers and rhizomes. Among the animals are small invertebrates (insects and their larvae, small mollusks, crustaceans), as well as small fish, tadpoles and even adult frogs. Usually they get food from the surface of the water or, by dipping their head and neck into the water, stand in the water almost vertically with their tail up, trying to reach the plants on the bottom; they do not dive.
In winter, the diet of mallards sharply reduces the amount of animal feed (due to their absence), and the basis of nutrition at this time is the vegetative parts of various aquatic plants and their seeds.
In early spring, when the reservoirs are still under the ice, mallards stay on the sagebrush, feeding on overwintered green parts of plants.
In late summer and autumn, the mallard's diet is also dominated by plant foods, including seeds of agricultural cereals. During this period, flocks of ducks often fly to feed on grain fields, where they collect fallen grain-wheat, rye, oats, millet, and in southern Primorye – rice. Ducks spend all night in the fields, returning to the reservoirs only in the morning.
In urban reservoirs, mallards live mainly due to feeding and very quickly get used to their dependency, ceasing to be afraid of humans. (Sometimes, unfortunately, it ends badly for them.)
Nesting and nesting behavior.
Mallards begin to nest at the age of one year. In sedentary populations, the split into pairs occurs in the fall, in the rest-in the spring upon arrival in the nesting areas. Since in many migratory populations, the females overwinter south of the males, they arrive at the nesting sites later. The beginning of the breeding season depends on the latitude of the area – in the southern parts of the range it falls in February, in the northern-in June.
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