Exposure to external repeated or long-term stressors can alter animal behaviour and physiology. At zoos, construction of new buildings and habitats is one potential unavoidable long-term stressor. During the construction of a new exhibit near the giraffe enclosure at Lincoln Park Zoo (Chicago, IL), the Zoo’s two female giraffes, Giraffa camelopardalis rothschildi and Giraffa reticulata, were monitored for changes in behavior and faecal glucocorticoid metabolite (FGM) levels during five phases of construction and enclosure access. The FGM analysis was validated