Biology of Black Rat

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The black rat is known by more than a few names, and you may have heard of it being referred to as the house rat, the ship rat, the roof rat, and more. It’s technical name is “Rattus Rattus”, and it once started its like in the sub tropics of Asia, before spreading East throughout the Roman era.


The black rat is a small animal, usually measuring less than 8 inches in length, not including the tail. The tail itself can grow to over 6 or 7 inches in length, and it is this that helps it to maneuver itself around in the height of trees and buildings.

The name “black rat" is actually a little misleading. This rat is not usually black at all, but rather more of a dark brown or grey color. It can be different colors in different areas, and some sub-species now have an almost-green tinge to their fur. Generally, the black rat is smaller than the more common brown rat.


An omnivore, the black rat is a rather pesky pest to farmers particularly, with a love for all things agriculturally based. It will eat animal matter too, having a penchant for things such as vertebrates and invertebrates, and it will also consume fungi, seeds and stems, fruit, leaves, and more. In short, these rodents are scavengers, and they will eat practically anything that you could put out for them. They will even make a meal out of food left out for farmyard animals, such as cow and sheep, and they definitely won't turn their noses up at free dog and cat food if it's left out on the back porch.

According to studies, the black rat can eat as much as 15g of food per day. That's pretty impressive for an animal that only weighs in at around 75g to 200g itself.


The black rat prefers warmer climates, unlike it’s brown rat cousin, and they're also slightly more particular about what they eat. This is why the brown rat is the more dominant species over the two, and the brown rat will often push the black rat out.

The black rat, just like the brown rat, is very well adapted to living alongside humans, and you will more than likely find this species living alongside us in human habitats than you will out in the wild. Residential buildings and warehouses are preferred spots, mostly because they are left along and to their own devices for long periods of time usually. They prefer to live up high than down low, and you will often find this particular species of rat in the attic and upper crawl spaces, rather than down in the basement of your building. They are good climbers, and this makes getting higher a lot easier. They will also make homes in trees in the “wild”.


One of the most widespread species of animal in the world, one of the reason behind the black rats popularity, and its spread across the world, is the speed at which it can reproduce. Both the brown rat and the black rat can reproduce at a staggering rate, much quicker than most other animals. They will breed multiple times per year, and they can have between 5 and 15 babies in each litter. These baby rats will become sexually active at only a few weeks of age - 3 to 4, an that's when the cycle will start all over again. That's why you don't want one rat in your home, let alone an infestation of them, and is also why you should be inspecting your home regularly to ensure there are no signs of damage that could be letting them in.

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