 The warnings were ignored and stoats began to be introduced from Britain in the 1880s, resulting in a noticeable decline in bird populations within six years.Stoats are a serious threat to ground- and hole-nesting birds, since the latter have very few means of escaping predation.The highest rates of stoat predation occur after seasonal gluts in southern beechmast (beechnuts), which enable the reproduction of rodents on which stoats also feed, enabling stoats to increase their own numbers.