Mongoose are like the curious little mascot of St. Croix. Mongoose is the popular English name species in the 14 genera of the Herpestidae family , which are small carnivorans that are native to southern Eurasia and mainland Africa. You’ll catch these quick little rodents scurrying across the road, or even taunting an iguana. Mongoose were brought to the island to eradicate the rat problem. Well, problem was, rats were nocturnal (they like the night time) and mongoose are diurnal (they like the day time); which means that little plan didn’t work out so well.