The mongoose was introduced into Hawaii to help control the rats, but the rat is a nocturnal animal. That means it is active at night, and sleeps during the day.

The mongoose is a diurnal animal. That means that it is active during the day and sleeps at night.

Now, Hawaii has both rats and mongoose. The mongoose are as bad an alien pest as the rats are. Both of them have been very harmful to the native populations of birds and tree snails.

The mongoose is an alien that never should hve been introduced to Hawaii.