Habitat: The black rat was widespread in Europe and North America centuries ago, when it had more opportunities to live alongside humans. But gradual improvements in pest control have almost eliminated it from both regions. Today, the black rat is more prevalent in warmer climates, which it prefers. In the tropics it may live outside among rocks or in tree stumps, especially in locations where food is plentiful.
In cooler climates the black rat is found almost exclusively in ports and docks. 

It lives on the upper floors of warehouses and granaries, nesting in warm holes, especially during winter. Unlike the related brown rat, which is often found in ditches and sewers, the black rat rarely swims. Using its long tail for balance, the black rat can easily run along a ship’s rigging. The black rat has good eyesight and a keen sense of smell. It is at home in granaries and warehouses, which provide food and protection. The black rat rarely goes outside in a cool climate.

Breeding: The black rat is active mostly at night, and little is known about its social habits. It is a prolific rodent and breeds throughout the year with a peak breeding period in the summer. Mild winter extend the breeding season, causing an increase in the population. Once a pair has mated, the male leaves the female and looks for other females to mate with. Three weeks after mating, the female gives birth to five to ten babies in a nest of rags, straw, and paper. Born blind, deaf, and hairless, the young huddle together to keep warm. After a week their eyes open, they can hear, and their coats start to appear. At three months, the young rats leave their mother and are ready to mate.

Black Rat and Man: The black rat carries many fatal diseases including typhus and salmonella. It also hosts the Oriental rat flea, which spreads bubonic plague. For centuries, people have been trying to exterminate the black rat as well as other rats. Today, the population of the black rat is steadily diminishing in cool climates, where it lives in buildings and is easier to control than the brown rat. The black rat is less easy to control in warmer climates, where it often lives outdoors.

Food and Feeding: The black rat prefers cereals and fruit to live prey. In the tropic it eats coconuts and sugarcane. This rat causes great damage in grain stores because it has to gnaw constantly to keep its ever growing teeth at the right length. It splits open the sacks of grain and eats as much as it can. Then it destroys what is left by trampling on and urinating over the remains. The black rat primarily cereals and fruit. Like the house mouse, it holds its food in its forepaws while it eats.

Key Facts:
Sizes:
Length: Head and body, up to 9 in. Tail, up to 10 in. Male slightly larger than female
Weight: 5-7 oz.

Breeding:
Sexual maturity: 3 months
Breeding season: Throughout the year in warm climates
Gestation: 3 weeks
No. of young: 5-10

Lifestyle:
Habit: Sociable, forming colonies near human habitations
Diet: Mostly vegetable matter; prefers grain and fruit
Lifespan: Average 1 year

Related Species: There are 78 species of Rattus, including the brown, or Norway, rat, R. norvegicus, which is common near human habitations.
Distribution: The black rat is native to warmer parts of the world. It arrived in North America as a stowaway on ships and is now found in many cities, mainly along the coasts.
Conservation: In colonial times the black rat was abundant in American cities, but it is now outnumbered by the more adaptable brown rat. Neither species is likely to become extinct.

Identifying the Black Rat: Variations in coat color make it easy to confuse the black rat with the brown rat, but there are clear differences between them.
Coat: Although its color varies, the black rat’s coat is sleeker and glossier than the brown rat’s coat.
Ears: Smaller on the black rat. They are pink and naked, while the brown rat’s are pale and covered with hairs.
Tail: The black rat has a longer tail in proportion to its body, although it is smaller overall than the brown rat.
Oriental rat flea: Carried from Asia and the Middle East in the rat’s coat. It spread the bubonic plague in Europe.

Did You Know:
The largest member of the rat family is the cloud rat of the Philippines, with a body nearly 16 inches long.
About 95 percent of black rats die before they are a year old. Pesticides are largely responsible for this

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