Rufous-bellied Thrush
Encyclopedia
The Rufous-bellied Thrush (Turdus rufiventris) is a songbird
of the thrush
family
(Turdidae). It occurs in most of east and southeast Brazil
from Maranhão
south to Rio Grande do Sul
states, Bolivia
, Paraguay
, Uruguay
and northern regions of Argentina
.
It is one of the most common birds across much of southeastern Brazil, and is well-known there under its local name sabiá-laranjeira. The Rufous-bellied Thrush has been the state bird of São Paulo
since 1966. It was proposed as the national bird of Brazil, and was officially chosen in 2002.
This species
is named after its distinctive reddish-orange underparts. Rufous-bellied Thrushes can reach a length of 25 cm and weigh up to 68 g (male) or 78 g (female), though weights of about 59 g for males and 64 g for females are more usual. Contrary to what one might expect from the rather marked weight difference, the females are not larger, only plumper; their tarsus
is actually a bit shorter than that of males on average.
Found in forests and urban wooded areas, it is an omnivorous bird. Its food consists mainly of fruits and arthropod
s, and it can sometimes be seen attending mixed-species feeding flock
s and moving through the bushes with many other birds. It has been observed to squabble with a Common Marmoset
(Callithrix jacchus) in the undergrowth over food flushed by an army ant
column, but this was during the dry season
when fruits are scarce.
It builds an open-cup nest
, sometimes right on the forest floor, sometimes more than 20 meters high in a tree, but usually 4–5 meters above ground. In the yungas
of NW Argentina, nesting occurred in the wet season from October to March, with most birds breeding in November–December. The three, sometimes two eggs measure about 27-28 by 20 mm, and weigh c.5.7-5.9 grams each. They are incubated for about 12–13 days, and young take about that long again untlil they fledge
. Incubation is solely by the female, which spends considerable time on the nest. The nestlings are attended by both parents however; as the young near fledging, they are fed every 5–7 minutes or so on average. Predation
may be a major cause of brood failure; in the Southern Andean
yungas it was noted to be especially high during the nestling time and far less significant during incubation.
This common and wide-ranging species is not considered threatened by the IUCN.
Songbird
A songbird is a bird belonging to the suborder Passeri of the perching birds . Another name that is sometimes seen as scientific or vernacular name is Oscines, from Latin oscen, "a songbird"...
of the thrush
Thrush (bird)
The thrushes, family Turdidae, are a group of passerine birds that occur worldwide.-Characteristics:Thrushes are plump, soft-plumaged, small to medium-sized birds, inhabiting wooded areas, and often feed on the ground or eat small fruit. The smallest thrush may be the Forest Rock-thrush, at and...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
(Turdidae). It occurs in most of east and southeast Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
from Maranhão
Maranhão
Maranhão is a northeastern state of Brazil. To the north lies the Atlantic Ocean. Maranhão is neighbored by the states of Piauí, Tocantins and Pará. The people of Maranhão have a distinctive accent...
south to Rio Grande do Sul
Rio Grande do Sul
Rio Grande do Sul is the southernmost state in Brazil, and the state with the fifth highest Human Development Index in the country. In this state is located the southernmost city in the country, Chuí, on the border with Uruguay. In the region of Bento Gonçalves and Caxias do Sul, the largest wine...
states, Bolivia
Bolivia
Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...
, Paraguay
Paraguay
Paraguay , officially the Republic of Paraguay , is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the...
, Uruguay
Uruguay
Uruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...
and northern regions of Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
.
It is one of the most common birds across much of southeastern Brazil, and is well-known there under its local name sabiá-laranjeira. The Rufous-bellied Thrush has been the state bird of São Paulo
São Paulo (state)
São Paulo is a state in Brazil. It is the major industrial and economic powerhouse of the Brazilian economy. Named after Saint Paul, São Paulo has the largest population, industrial complex, and economic production in the country. It is the richest state in Brazil...
since 1966. It was proposed as the national bird of Brazil, and was officially chosen in 2002.
This species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
is named after its distinctive reddish-orange underparts. Rufous-bellied Thrushes can reach a length of 25 cm and weigh up to 68 g (male) or 78 g (female), though weights of about 59 g for males and 64 g for females are more usual. Contrary to what one might expect from the rather marked weight difference, the females are not larger, only plumper; their tarsus
Tarsus (skeleton)
In tetrapods, the tarsus is a cluster of articulating bones in each foot situated between the lower end of tibia and fibula of the lower leg and the metatarsus. In the foot the tarsus articulates with the bones of the metatarsus, which in turn articulate with the bones of the individual toes...
is actually a bit shorter than that of males on average.
Found in forests and urban wooded areas, it is an omnivorous bird. Its food consists mainly of fruits and arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s, and it can sometimes be seen attending mixed-species feeding flock
Mixed-species feeding flock
A mixed-species feeding flock, also termed a mixed-species foraging flock, mixed hunting party or informally bird wave, is a flock of usually insectivorous birds of different species, that join each other and move together while foraging...
s and moving through the bushes with many other birds. It has been observed to squabble with a Common Marmoset
Common Marmoset
The common marmoset is a New World monkey. It originally lived on the Northeastern coast of Brazil, in the states of Piaui, Paraiba, Ceará, Rio Grande do Norte, Pernambuco, Alagoas and Bahia...
(Callithrix jacchus) in the undergrowth over food flushed by an army ant
Army ant
The name army ant is applied to over 200 ant species, in different lineages, due to their aggressive predatory foraging groups, known as "raids", in which huge numbers of ants forage simultaneously over a certain area, attacking prey en masse.Another shared feature is that, unlike most ant...
column, but this was during the dry season
Dry season
The dry season is a term commonly used when describing the weather in the tropics. The weather in the tropics is dominated by the tropical rain belt, which oscillates from the northern to the southern tropics over the course of the year...
when fruits are scarce.
It builds an open-cup nest
Nest
A nest is a place of refuge to hold an animal's eggs or provide a place to live or raise offspring. They are usually made of some organic material such as twigs, grass, and leaves; or may simply be a depression in the ground, or a hole in a tree, rock or building...
, sometimes right on the forest floor, sometimes more than 20 meters high in a tree, but usually 4–5 meters above ground. In the yungas
Yungas
The Yungas is a stretch of forest along the eastern slope of the Andes Mountains from southeastern Peru through central Bolivia. It is a transitional zone between the Andean highlands and the eastern forests. Like the surrounding areas, it has characteristics of the Neotropic ecozone...
of NW Argentina, nesting occurred in the wet season from October to March, with most birds breeding in November–December. The three, sometimes two eggs measure about 27-28 by 20 mm, and weigh c.5.7-5.9 grams each. They are incubated for about 12–13 days, and young take about that long again untlil they fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
. Incubation is solely by the female, which spends considerable time on the nest. The nestlings are attended by both parents however; as the young near fledging, they are fed every 5–7 minutes or so on average. Predation
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
may be a major cause of brood failure; in the Southern Andean
Andes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
yungas it was noted to be especially high during the nestling time and far less significant during incubation.
This common and wide-ranging species is not considered threatened by the IUCN.
External links
- Rufous-bellied Thrush videos on the Internet Bird Collection
- Rufous-bellied Thrush photo gallery VIREO