Reproductive biology

Typically the male feeds berries to the female as part of courtship. Mutual preening is also an important aspect of courtship. Toucans form monogamous pairs.

Eggs are ellipitical and white. The clutch typically ranges from two to four eggs, though as many as six may be laid in some species. The egg may be as heavy as 5% of the weight of the female in some species. Incubation lasts approximately 18 days, but this depends on the species. Both parents incubate.

Toucans nest in tree holes, usually high above the ground; the larger species prefer natural cavities in rotted trees, while the smaller ones often use woodpecker holes. Chestnut-eared aracaris will nest in abandoned tree-termite nests. Toucans

A pair of collared aracaris (Pteroglossus torquatus) share a branch. (Photo by T.J. Ulrich/VIREO. Reproduced by permission.)

sometimes drive woodpeckers away from newly excavated nest holes, and then enlarge the entrance if it is too narrow for them. The floor of the hole is typically 3-8 in (8-20 cm) below the opening. Toucans sometimes lay their eggs in the same hole year after year. The eggs lie on wood debris, or often on a lining of seed pellets that the birds have regurgitated before egg laying.

Newly hatched toucans have bare red skin that is not covered with down. Their bills are short, with the lower bill longer and wider than the top, as is the case with young woodpeckers. Thick, horny swellings on the heels protect these joints from friction. The heel pads have sharp outgrowths that may form a ring; these "tarsal calluses" fall off after the young leave the nest.

Both parents brood the naked nestlings, and parents also share the work of feeding their young. They bring some of the food in the tips of the bill, but most food is carried in the throat or esophagus and regurgitated at the nest. Parents and older nestlings clean the nest hole and carry refuse away in their bills. Young toucans open their eyes after they are three weeks old. Their feathers grow so slowly that young still show much bare skin even after they are a month old. Young of the largest species probably remain in the nest for about 50 days. Fledglings typically begin feeding themselves 8-10 days after leaving the nest.

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