Size and color
A typical adult black rat is 12.75 to 18.25 cm long, not including a 15 to 22 cm tail, and weighs 75 to 230 Grams, depending on its subspecies. Despite its name, the black rat exhibits several color forms. It is usually black to light brown in color with a lighter underside.
Black rats have an unusual distribution and importance, in that they are utterly pervasive through native forests, scrub-lands, and urban park lands. This is typical only of oceanic islands that lack native mammals, especially other rodents. Throughout most of the world, black rats are found only in disturbed habitats near people, mainly near the coast.
Black rats adapt to a wide range of habitats. In urban areas they are found around warehouses, residential buildings, and other human settlements. They are also found in agricultural areas, such as in barns and crop fields. In urban areas they prefer to live in dry upper levels of buildings, so they are commonly found in wall cavities and false ceilings. In the wild, black rats live in cliffs, rocks, the ground, and trees. They are great climbers and prefer to live in trees, such as pines and palm trees. Their nests are typically spherical and made of shredded material, including sticks, leaves, other vegetation, and cloth. In the absence of trees, they can burrow into the ground. Black rats are also found around fences, ponds, riverbanks, streams, and reservoirs.
Black rats are considered omnivores and eat a wide range of foods, including seeds, fruit, stems, leaves, fungi, and a variety of invertebrates and vertebrates.