Maguari Stork

If the Maguari Stork nests in bushes or shrubs less than 6 m high to the north of its range, for example in the Llanos of Venezuela, elsewhere, in Brazil and Argentina, it mainly nests on the ground in marshlands.
Couples can nest isolatedly or they can get together with other birds to form small, loose colonies of 5 to 15 nests, mixing with other species when necessary. In Venezuela a study showed that colonial reproduction accounted for 77% of the couples and that reproductive success was higher there.
From one year to the next, the couples return to the same zone, sometimes on the same site.

The formation of couples is original, at least where nesting is on the ground. Parades and pairing take place away from the nesting zone. If the parades are similar to what is generally observed in other storks, bill clapping is rare and mainly occurs during confrontations between males.
The couple generally builds a new nest, the old one rarely being reusable. The nests built in trees can measure 2 m in diameter and 75 cm thick, they are made of branches and then lined with moist grass, which hardens as it dries. On the ground, the nests are usually made of reeds, then covered with grass and aquatic plants. Built on the bottom of the marshes, they measure up to 2.50 m in diameter and one meter in height and are 50 cm higher than the water level.
Mating takes place on the nest. The female lays 2 to 4 eggs, 2 to 3 days apart. They are incubated from the time the second one is laid. Incubation lasts 29 to 32 days, alternately taken care of by the two parents.
At first covered with a sparse white down, the chick then gets a very dark, almost black down, which it will keep until the juvenile plumage grows.This dark plumage sometimes mixed with a hint of white down is unique among storks. It would help to camouflage the nests. The young are never left unattended until they are 6 weeks old. They leave the nest after about two months, then weighing in at 4 kg, a bit more than their parents. They form groups with other young from the colony, continue to be fed by their parents, and return to the nest at night for another 6 weeks. Sexual maturity is reached at 3 years old for males and 4 years old for females.