Brush-tail Possum - clinging to a tree branch (Trichosurus vulpecula). Waitomo, North Island, New Zealand. The Brush-tail Possum is a nocturnal animal which was introduced to New Zealand by pioneer farmers. Together with other introduced predatores it does threaten native birds like the Kiwi or the Bellbird. It eats their eggs and is a competitor for fruit and other feeding plants. There are special hunting and poisoning programs in place to reduce their population.