Bio Facts: Ibis, Scarlet
Argentina, Brazil, Colombia, French Guiana, Guyana, Netherlands Antilles, Suriname, Trinidad and Tobago, and Venezuela; Vagrant: Aruba, Belize, Cuba, Dominica, Ecuador, Grenada, Jamaica, and the United States
Swampy environments such as mud flats and shallow bays; during the breeding season, they nest on dense brush-covered islands and mangroves near the mouths of rivers.
Adult length: 22 to 24 in. (56–61 cm); weight: 1.4 lbs. (650g); wingspan: about 21 in. (54.1 cm); coloration: completely scarlet with black wing tips.
About 15 years in the wild, and up to 20 years in captivity
In the wild, they eat frogs, reptiles and crustaceans; in the Zoo, they are a scientifically developed, commercially available bird of prey diet, capelin, vitamins and minerals.
IUCN – Least Concern; CITES – Appendix II; USFWS – Migratory Bird Treaty Act
Scarlet ibises fly in large flocks between different feeding and roosting sites. In flight, the birds will soar and also glide at great heights and speeds. If disturbed, sometimes all the birds of a nesting area will take flight at once. Territorial disputes between males are settled by size.
The scarlet ibis range is varied and extensive, because of nomadic movements between nesting and foraging sites. Shifts occur between the interior wetlands of northern South America to coastal locations. More specifically, birds forage between the higher and lower llanos of South America. Nesting then takes place in northwestern Colombia and along the Atlantic coast and into Brazil where it nests along the northeastern coast.
The scarlet ibis is a colonial and social breeder. Nests are generally built close to one another with more than one per tree. This is most likely done to reduce the risks of predation. Males use displays of preening, flights, head rubbing, and a rocking motion to attract mates. A female must be cautious when approaching a male, because he may actually attack her if she does not remain in his display area. Scarlet ibises are polygynous; the males often mate with more than one female.
Ibises begin visiting nesting sites by mid-September; egg-laying takes place from early November through December. The first egg is laid 5 to 6 days after copulation and there are usually 3 to 5 eggs in each nest. Eggs are not glossy, but are smooth. Incubation lasts between 19 to 23 days. Chicks fledge after 35 days and are independent in 75 days.
Young ibises are altricial, when they first hatch; they are helpless and cannot even hold up their heads. Both adult birds share in the responsibilities of caring for and tending to the young. Both incubate, provide food and also guard against predators. To feed their chicks, adults grab hold of the bill of the young bird, which causes it to raise its head so that the parent can regurgitate into the mouth. The chick’s feet develop quite fast; this allows the chicks to fledge as early as 2 weeks. By 40 days old, the young are able to fly well and by 75 days old, they are able to provide for themselves and can leave the colony.
Scarlet ibises produce honking noises to communicate disturbances in the nest and also use the noise in courtship. The young have a shrill cry that they use to let parents know that they are in need of food. Touch is important during courtship. The males and females make greeting displays to one another and then wrap necks. The male produces the honking noise during courtship, while the female produces more of a squealing sound.
Using its long curved bill, scarlet ibises forage for food by either probing in water or pecking for prey items on soil surfaces.
The greatest risk of predation is from large cats and birds of prey. Their best defense is safety in numbers, their social and colonial habit. Males use their larger size to defend their young and female mates. The large grouping is also useful because when predators are spotted they produce warning calls to warn the others of danger.
Young ibises have approximately a 50% mortality rate. In general, colonies suffer from high mortality rates due to predation and lack of food.
A juvenile Scarlet Ibis is grey and white. As it grows, the ingestion of red crabs in the tropical swamps gradually produces the characteristic scarlet plumage. The feather color comes from the synthesis of carotene found in their diet.
While the species may have occurred as a natural vagrant in southern Florida in the late 19th century, all recent reports of the species in North America have been of introduced or escaped birds. Eggs from Trinidad were placed in white ibis nests in Hialeah Park in 1962, and the resulting population hybridized with the native ibis, producing “pink ibises” that are still occasionally seen.
It is the national bird of Trinidad and is featured on the Trinidad and Tobago coat of arms. It is locally known as “flamingo,” and makes its home in the Caroni Bird Sanctuary in the Caroni Swamp—an area set aside by the government for the protection of these colorful birds.
The scarlet ibis lives among many other wading birds. While it can live harmoniously with other species, it also defends its individual space very aggressively. Other birds often steal the scarlet ibis eggs, so it must be protective of its territory. Because of its large colonial sizes (which can have anywhere from 20 to 600 nests, and sometimes even up to 2000 nests), the scarlet ibis contributes significantly to the energy flow of organisms in the environment where it is found. It has been noted to be responsible for 10% of the energy flow through the community.
This species forages for food with many other types of wading birds, such as storks and spoonbills and specifically has been seen living with Brazilian wading ducks. One reason that the species may be mutualistic in sharing feeding areas is that it allows for a great number of birds to feed communally at its site, and then it has a better chance to hide from predators among all the other birds. Also, many wading birds together stir up the shallow water and disturb the prey so that they are easier to find and catch.
The word ibis comes from Greek and Latin, and probably from the Ancient Egyptian. According to Josephus, Moses employed ibises against serpents during a desert campaign into Ethiopia in his early life. Pliny the Elder also recounted, “The Egyptians invoked [ibis] against the serpents.”
The importance of the scarlet ibis dates back to the 16th century when Indian tribes would use the bright feathers for adornment and also eat the meat of the bird. In areas where it is not protected, people still consume scarlet ibis meat and eggs and continue to use feathers as decorative objects.
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion. Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion. The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion. For these reasons the species is evaluated as Least Concern.
Many environmental and human threats exist for scarlet ibis. Overhunting, the harvesting of eggs and the selling of young as pets in open-markets are affecting population sizes. Other crucial aspects threatening the species revolve around habitat loss. Nesting ground destruction and loss of foraging and feeding grounds are serious problems, along with heavy pollution in these now limited areas. Disturbance of breeding and foraging areas because of recreational activities such as boating, also affect nesting populations. There are laws and regulations that have been issued to protect scarlet ibis habitats and protect it from hunting. However, in many areas, law enforcement is weak. In order to sustain populations, pollution must be controlled in their breeding and feeding areas, and people living in rural areas should be educated about the bird.
Jacksonville Zoo History:
Scarlet Ibis were part of our Zoo’s animal collection from 1969 to 1996, and then were brought back in 2004. Our Scarlet Ibis chicks are highly sought after by other zoos in North America.