The American visitor to the South Island bush. A deer with a flag. The white-tailed deer is a medium-sized deer, with a reddish-brown coat in summer that fades to a grey-brown in winter. The name comes from the white underside of the tail, which the deer flips up like a flag when it is alarmed. The males grow forward-curving antlers with several tines. A deer that signals danger with its tail. These animals are the browsers and grazers of the forest edge. They eat leaves, shoots, grass and crops, causing damage to native forests and pasture. They are also excellent swimmers, crossing rivers and lakes with ease. When alarmed, they run with a distinctive, bouncing gait, tail raised, warning other deer of danger. White-tailed deer were brought to New Zealand by hunters who wanted to introduce a new game species. They established in the lower South Island and have been there ever since. To see a white-tailed deer is to see a flag of the forest. A bouncing, tail-flashing, antlered deer that belongs in North America but has made a home in the South Island bush. The white-tailed deer's flagging tail is one of the most effective alarm signals in the animal kingdom. When a deer senses danger, it raises its tail, flashing the bright white underside. Other deer see the flash and run. The signal travels faster than the deer itself, warning the herd before the predator arrives. In the forests of Otago and Southland, that white flag is a common sight. It flashes through the undergrowth, and then the deer is gone. The forest is quiet. The deer grazes at the edge. A twig snaps. The tail flashes white. The deer is gone. It does not know it is a visitor. It does not know it is a pest. It just wants to avoid danger. The flag still flies, but only when the deer is already gone.