The house sparrow Passer domesticus) is a well-known bird in the Netherlands and Belgium. It is a sturdy bird with a large round head, a short thick neck and a cone-shaped beak for cracking seeds. It gives the house sparrow a stocky appearance to behold. The bird breeds and resides in the immediate vicinity of humans all year round.
- The house sparrow (Passer domesticus)
- Characteristics of the house sparrow
- Colors of the male
- Male house sparrow resembles the tree sparrow
- Colors of the female
- Bathe in a dust or sand bath
- Reproduction
- Eggs and juveniles
- The fledging of the sparrows
The house sparrow (Passer domesticus)
The house sparrow (Passer domesticus) is a passerine bird in the family Passeridae (Sparrows) where it forms the genus Passer together with about thirty other species. The house sparrow is very similar to the tree sparrow (Passer montanus), also a species from the genus Passer and also a common bird in the Netherlands and Belgium.
Characteristics of the house sparrow
The house sparrow is a stable and social bird that lives in groups and can be seen in and around the vicinity of people. House sparrows stay and nest near buildings (preferably under roof tiles), in trees and hedges, but also use nesting boxes. The birds are resident and if they have fun they can stay in the same place for years with a large number of congeners (colony brothers), both in winter and summer. The bird, up to 15 centimeters in size, has a wingspan of about 25 centimeters and a weight of over 40 grams. The short legs are brownish pink in color. The house sparrow has four toes, three of which are forward and one backward. A special muscle (the tibiotarsus) allows the birds to sit on thin branches without falling off. With the short cone-shaped bill, they mainly eat grain, weed seeds, vegetables, leaves and fruits. When there are youngsters, the house sparrow also wants to add insects to its menu. The sound of a house sparrow is a characteristic chirping in many variations. The male is clearly distinguishable from the female, because the former is blacker and more brown. The habitat (habitat) of the house sparrows depends on whether there are enough places to build nests, enough food to find, enough shrubs and trees to hide in and whether there are places to bathe in water or sand .

Colors of the male
The male house sparrow has a gray crown, a gray cheek patch, a black patch on the chest (bef) and a black mask around the eye with a light patch behind the eye. The house sparrow has black-brown wings with a white wing stripe. The solid beak of the house sparrow is black during the breeding season and much lighter in color after the breeding season. The underside is uniformly grayish. In winter the house sparrow is less brightly colored.
Male house sparrow resembles the tree sparrow
The male in particular resembles a tree sparrow (there is little difference between the male and female tree sparrow), but the tree sparrow has a brown crown on the head, is less black on the chest and has a dark cheek patch with a ring-shaped white stripe that almost continues around the neck.

Colors of the female
The females differ from the males in that the females are lighter and duller in color. The female has a brown crown on the head and a beige eye stripe. The belly is a uniform light gray-brown in color and the back is soft brown and black striped with a white wing stripe and often white feathers here and there. The sturdy cone-shaped bill is light in color.
Bathe in a dust or sand bath
The house sparrows need water as a nutrient in the summer and winter to care for their feathers and in the summer to cool off in hot weather. In the absence of water, the house sparrow is a bird that settles for a sand or dust bath to take care of its feathers. While bathing in the dry sand, the house sparrow turns around and over, rubs the dusty sand into the feathers and shakes the sand out again. By sanding the sand, the feathers are cleaned of coccyx gland fat (necessary to protect the plumage of the house sparrow against moisture) and harmful parasites such as lice and mites.

Reproduction
In the fall, the sparrow begins to look for a place to build a nest from blades of grass, straws, twigs, stems and roots of plants. This can be under the roof tiles of a house, a nesting box or in a large hedge (conifer hedge or ivy). He prefers to have a roof over his head.
In January, the gonads start to grow in the males, which are at their largest in the spring and then decrease again in June. The male house sparrow chirps loudly in front of the nest in mid-April and when a female sparrow shows interest, the male chirps out loudly, lets the wings hang down and starts wiggling the tail. When the female approves the nesting area, the sparrows mate and together they build the spherical nest on the inside with tufts of sheep’s wool, horsehair, moss, dandelion fruit fluff or feathers.

Eggs and juveniles
A week after mating, the female lays five to six white, blue-white or light green eggs covered with gray to brown spots. Then both parent sparrows start brooding and after about two weeks the young hatch. The young, naked chicks weigh about three grams and have a large yellow border along the beak. When a parent bird approaches the nest, the young house sparrows open their mouths wide (barrier behavior) so that father or mother house sparrow knows where the food should go. During the first days, the young house sparrows are fed mostly animal food, such as aphids, beetles, flies, moths, grasshoppers, larvae and spiders. After the first days of feeding with animal food, there is also feeding with vegetable food. Soaked seeds first and after a week of normal hard seed and the older the youngsters get, the greater the share of the vegetarian food becomes. The urine and faeces of the young birds end up in a poop bag that is cleaned up from the nest by the parents during the first days and is later deposited outside the nest by the young birds themselves.

After about 17 days, the young house sparrows (juveniles) fledge and are fed by the parents for another two weeks. About nine days after the young have fledged, the female starts a second clutch and the male takes care of the young from the first clutch. The house sparrow can have two to three clutches per breeding season, from April to August.
The fledging of the sparrows
The youngsters fledge is encouraged by the male. First the male reduces the amount of food and then he lures the young out.