In Hawaii in the 1800’s the sugar industry was facing problems from the growing rat population which was eating through their sugar plantations and costing them a lot of money. In order to try and control the rat population, a predator was introduced to the islands, in 1833 Mongooses, which are originally native to India, were let loose in the fields of Hawaii to end the rat threat to the agriculture.
However this decision seemed to be incredibly misinformed, rats are a nocturnal animal which means they are only active at night and spend the days hidden away in nests, however the Mongoose is diurnal, which means they only hunt in the daytime and nest at night so the two animals would never encounter each other!
The rat population proceeded to increase, they are intelligent and able to adapt to a new predator quickly and were met with no real threat to their usual sugarcane eating habits. However, the other native animals on the island including birds, turtles, reptiles and various other small mammals were suddenly met with a a new, very real threat from the Mongoose which proceeded to ravage native populations that were causing no human threat.
As the population of mongooses grew (with no effect on the rat problem), the islanders started to put bounty’s on their heads to try and inhibit their population but the mongoose is intelligent, elusive, incredibly fast and proved very difficult to catch. With no natural predators the population continues to grow to this day, causing devastating damage to native animals populations, with some now facing near extinction.
The mongoose have spread to other islands as well and even though there were only 72 which were initially introduced to the islands, the current number is much, much more.