Are Black or Brown Rats Worse?

Unless you're some kind of rat racist, you won't really find one of the species to be worse than the other. Both brown rats and black rats have been known to carry potentially deadly diseases. Rat-bite fever is, unsurprisingly, transmitted by rats.

What is the difference between brown rats and black rats?

Appearance. The Brown Rat is the larger of the two, often weighing over half a kilo and measuring about 23cm, without counting the tail. The Black Rat weighs half as much and is shorter. It has a pointed muzzle, large, almost hairless ears, a more slender body, and a long thin tail that is longer than its body.

Are black rats harmful?

Diseases. Black rats (or their ectoparasites) can carry a number of pathogens, of which bubonic plague (via the Oriental rat flea), typhus, Weil's disease, toxoplasmosis and trichinosis are the best known.