page_title: Wood stork
section_title: Breeding
hierarchical_section_title: Wood stork / Behaviour / Breeding
caption_attribution_description: English: Stork Love again... Gatorland's rockin' &#160;:)
context_page_description: The wood stork is a large American wading bird in the stork family Ciconiidae. It was formerly called the "wood ibis", though it is not an ibis. It is found in subtropical and tropical habitats in the Americas, including the Caribbean. In South America, it is resident, but in North America, it may disperse to as far as Florida. Originally described by Carl Linnaeus in 1758, this stork likely evolved in tropical regions. The head and neck are bare of feathers and dark grey in colour. The plumage is mostly white, with the exception of the tail and some of the wing feathers, which are black with a greenish-purplish sheen. The juvenile differs from the adult, with the former having a feathered head and a yellow bill, compared to the black adult bill. The sexes are similar.
  The habitat of the wood stork can vary, but it must have a tropical or subtropical climate with fluctuating water levels. The one metre in diameter nest is found in trees, especially mangroves and those of the genus Taxodium, usually surrounded by water or over water. The wood stork nests colonially. The nest itself is made from sticks and greenery.
context_section_description: A resident breeder in lowland wetlands with trees, the wood stork builds a large stick nest in a tree. In freshwater habitats, it prefers to nest in trees that are larger in diameter. It nests colonially, with up to 25 nests in one tree. The height of these nests is variable, with some nests located in shorter mangrove trees being at heights of about 2.5 metres (8.2 ft), compared to a height of about 6.5 metres (21 ft) for taller mangrove trees. For Taxodium trees, it generally nests near the top branches, frequently between 18 and 24 metres (59 and 79 ft) above the ground. On the tree itself, forks of large limbs or places where multiple branches cross are usually chosen.
  The nest itself is built by the male from sticks and green twigs collected from the colony and the surrounding area. The greenery usually starts to be added before the eggs are laid but after the main structure of twigs is completed. The frequency at which it is added decreases after the eggs hatch. This greenery functions to help insulate the nest. When complete, the nest is about one metre (3.3 ft) in diameter, with a central green area having an average diameter of about 28 centimetres (11 in). The thickness of the edge of the nest usually measures from 12 to 20 centimetres (4.7 to 7.9 in).
  Wood storks without a nest occasionally try to take over others' nests. Such nest take-overs are performed by more than one bird. The young and eggs are thrown out of the nest within about 15 minutes. If only one stork is attending the nest when it is forced out, then it usually waits for its mate to try to take the nest back over.
  Breeding is initiated by a drop in the water level combined with an increased density of fish (with the former likely triggering the latter). This is because a decrease in the water level and an increased density of fish allows for an adequate amount of food for the nestlings. This can occur anytime between November and August. After it starts, breeding takes about four months to complete.
  This bird lays one clutch of three to five cream coloured eggs that are about 68 by 46 millimetres (2.7 by 1.8 in) in size. These eggs are usually laid one to two days apart and incubated for 27 to 32 days by both sexes. This incubation period starts when the first egg is laid. During the first week of incubation, the parents do not go far from the colony, with the exception of the short trips to forage, drink, and collect nesting material carried out by the non-incubating bird. After the first week, the non-incubating bird spends less time in the colony, although the eggs are never left unattended. After a few hours of incubation, this bird sometimes takes a break to stretch, preen itself, rearrange nest material, or turn the eggs. The eggs hatch in the order in which they were laid, with an interval of a few days between when each egg hatches.
  The chicks hatch altricial, unable to move, and weigh an average of 62 grams (2.2 oz). They are brooded for the first week after hatching, and after that when it is raining and at night. The chicks are not left alone until at least three weeks of age, with one parent foraging while the other guards the nest and chicks. When the chicks are at least three weeks old, they are large enough to stay and protect the nest. This coincides with the chicks getting more aggressive when presented with foreign objects or organisms. They fledge 60 to 65 days after hatching, and reach sexual maturity at four years of age, although they usually do not successfully fledge chicks until their fifth year of age.
  The hatching success, the percentage of birds that had at least one egg that hatched in a year, of the wood stork is around 62%. This can vary widely, though, with colonies ranging from about 26% to 89% hatching success. The period when chicks are most vulnerable to death is from hatching to when they are two weeks old. Overall, about 31% of nests produce at least one fledged bird. Raccoons and caracaras, especially northern crested caracaras, are prominent predators of eggs and chicks. Other causes of nesting failure is 
caption: Wood storks copulating
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