A very sociable bird often seen nesting in colonies called flocks. Sparrow is a very small bird, typically it can reach 10 to 20 centimeters in length and 22 to 40 grams in weight. The sparrows have a stout body covered with brown, black, and white feathers; the wings are rounded. Males and females can be distinguished by the feather coloration: males have reddish backs and have a black bib while the female on the other hand has brown backs with stripes. Although the sparrows do not belong to the group of water birds, they can swim very fast just to escape from their predators. Sparrows build their nest under a roof, a bridge, or in tree hollows.