Sika deer, the graceful spotted deer of Japanese and Chinese art, originally were native to Asia from far-east Russia to Vietnam to the islands of Japan and Taiwan. They are widely raised in captivity to supply velvet antler for traditional medicine. They also were introduced to Europe, North America, and New Zealand, where they compete or interbreed with native deer. Sika deer typically occupy lowland hardwood forests with low winter snow depths, where they thrive in sites disturbed by fire, storm, or logging. In high numbers they can severely impact vegetation though overgrazing,...