Black Rat - Ecology

Ecology

Black rats (or their ectoparasites) are able to carry a number of pathogens, of which bubonic plague (via the rat flea), typhus, Weil's disease, toxoplasmosis and trichinosis are the best known. It has been hypothesized that the displacement of black rats by brown rats led to the decline of the Black Death. This theory has, however, been deprecated, as the dates of these displacements do not match the increases and decreases in plague outbreaks.