However by 1900, the combination of deforestation and unregulated hunting brought wood ducks to the brink of extinction. Today, the wood duck population is thriving in North America, in part because hunting is regulated but more importantly because forests have begun to recover from earlier logging. Additionally, concerned conservationists have erected tens of thousands of nest boxes in the past 50 years to aid nesting wood ducks. Wood duck pairs begin arriving in Iowa from mid March to early April. Because they are not territorial, many wood ducks can share areas of good habitat.
Invertebrates provide the protein and calcium necessary for egg production.
Wood ducks naturally nest in tree cavities. Mature forests may have as many as 3 suitable cavities per acre. Black willow, basswood, soft maple, cottonwood and some oaks contain most of the suitable cavities. Cavities from 2 to 65 feet above the ground have been used successfully. Most wood ducks nest when 1 year old.