edging, although they can forage on their own at three months old. Ivory-billed woodpeckers seem to breed only once per year. Their age at sexual maturity is unknown. (Jackson, 2002)
Ivory-billed woodpeckers begin preparing for the arrival of their offspring at least two weeks before the first egg is laid. They select a dead or partially dead tree with wood that is soft enough for excavation but not so soft that it would provide easy access for predators. They then begin to excavate a cavity, usually just below an overhanging branch or stub (which may keep out rain and/or provide shade). There are conflicting reports on who does the excavating: some say that the male and female take turns and some say that the female does all the work herself. The resulting entrance hole is oblong in shape, about 11 cm wide and 14 cm tall. The cavity itself is about 25 cm wide at its widest point and measures about 54 cm from roof to floor. After the eggs have been laid, the male ivory-billed woodpecker roosts in the a cavity at night with the eggs, and later with the young. During the day the adults take turns brooding their altricial young. Feeding duties are shared more or less equally between males and females. Both feeding and brooding are most intense for the first few days after the eggs hatch and then gradually decline as the nestlings grow older; for example, 30 feedings per day drops to about 15 feedings per day later in the nesting period. Ivory-billed woodpeckers keep their nests fairly clean, but only males have been observed doing the cleaning, removing fecal material and dropping it away from the nest. Parents continue to feed their young for more than two months after the young fledge and the young may stay with their parents for over a year even though they are capable of feeding themselves at three months. (Jackson, 2002)
Ivory-billed woodpeckers are most active in the morning. At night they roost separately in tree cavities that they have excavated and after sunrise they emerge to preen and call their mates. They spend much of their time hitching themselves up tree branches and trunks in typical woodpecker fashion, searching for insects. At about midday there is a lull in activity. Occasionally they hop along on the ground to forage. Flight is graceful and direct; short flights are often accomplished in single swoops and longer flights are powered by steady wingbeats. When ivory-billed woodpeckers must travel a great distance they fly above the canopy. In late afternoon these birds return to their roost trees. They enter their roost cavities around dusk.
Ivory-billed woodpeckers are rarely found in large groups; the most ever observed together was 11 individuals. Small groups of three or four birds have been seen feeding in the same vicinity. Each mated pair has its own home range, but they are not territorial. They are not known to be aggressive toward one another, although they may scold intruding conspecifics. Group size and tolerance of other individuals may be related to habitat quality.
Ivory-billed woodpeckers seem to be sedentary, but some have suggested that they are nomadic, moving around to take advantage of dead trees left over from recent disturbance. (Jackson, 2002)
Home ranges are quite large; individuals in the U.S. have been observed traveling up to 4 km away from their nests. Taking this distance as the radius of a circle, the total home range size is about 50 square kilometers. Lamb (1958) calculated an even larger home range size for ivory-billed woodpeckers in Cuba, about 65 square kilometers. The fact that these woodpeckers have such large home ranges helps to explain why they require such large tracts of continuous forest in order to survive. (Jackson, 2002; Lamb, 1958)
Ivory-billed woodpeckers, like most birds, perceive their environment through visual, auditory, tactile, and chemical means. The relative acuteness of ivory-billed woodpeckers' senses is unknown, but presumably they have good vision and hearing as they use auditory and visual signals to communicate with one another. They have a di