Geographic Range
Spot-breasted orioles are found down the Pacific Coast of Mexico and Central America,
reaching from southern Mexico to Costa Rica. Found at a range of altitudes, from
below 500 m in Mexico and Costa Rica, and up to 1500 m in El Salvador and Honduras.
There are four recognized subspecies of spot-breasted orioles. The
I. p. carolynae
subspecies is native to southern Mexico, Pacific Coast of Guerrero and Oaxaca.
I. p. pectoralis
is native to southeast Mexico and east Oaxaca, central Chiapas south to Tonalá.
The
I. p. guttulatus
subspecies is native to southeast Mexico south to arid valleys of Guatemala, Honduras,
and northwestern Nicaragua. Finally, the
I. p. espinachi
subspecies is native to southwestern Nicaragua and northwestern Costa Rica. Spot-breasted
orioles have been introduced to the United States in southeast Florida.
- Biogeographic Regions
- neotropical
Habitat
Spot-breasted orioles prefer to nest and breed in areas of sparse arid woodlands,
with a native population of mimosa (
Mimosa
spp.), acacia (
Acacia
spp.) and mesquite (
Prosopis
spp.). Orioles are also known to frequent agriculturally developed areas such as
coffee plantations, villages and pastures, generally preferring to stay in areas with
large amounts of shade. In Florida spot-breasted orioles inhabit urban areas from
Palm Beach south to Miami, as long as there is enough shade and flowering trees.
All subspecies present in Mexico tend to stay in the lowlands. However, they can be
found in higher altitude areas further south into Guatemala.
- Habitat Regions
- tropical
- terrestrial
- Aquatic Biomes
- coastal
- Other Habitat Features
- suburban
- agricultural
Physical Description
Spot-breasted orioles have bright orange reddish hue covering the entirety of their
rumps, breasts, sides, vent, and also up towards the head covering the crown and nape.
They have black coloration on their tails, wings, and throat, with white patches on
the wings. Their major defining feature is the black spots present on the breast.
They do not exhibit sexual dimorphism, as females are only a slightly duller color
with a possible olive brownish hue to the underside of the tail. Elaborate coloration
in both sexes is common in tropical orioles.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Reproduction
All orioles are thought to be socially monogamous.
- Mating System
- monogamous
Spot-breasted Orioles are territorial with very distinctive nesting behavior and structure.
It constructs distinctive hanging nests made of dried grasses or thin roots and are
about 20 inches long and 5 inches wide at the base (typical of many closely related
orioles). These nests are known to hang in tall trees, spiny trees host to aggressive
stinging ants, or even suspended from power lines. Nests have also been known to
be parasitized by the
bronzed cowbird
. One very unusual behavior documented in Guatemala was the raising of two broods
at once; the male would take care of the first brood, while the female would begin
incubation on the second.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- oviparous
Females exclusively incubate the eggs, while chicks are fed by both parents. Little
is known about incubation and nesting periods.
- Parental Investment
- altricial
- male parental care
- female parental care
-
pre-hatching/birth
-
provisioning
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- male
- female
-
provisioning
Lifespan/Longevity
Little or no published information.
Behavior
While foraging, spot-breasted orioles are known to travel in pairs and small groups.
They forage insects by rummaging through dead leaves and gleaning from green leaves.
Spot-breasted orioles also known to snip bits of flowers (mainly Hibiscus) off using
their beak in order to get to the nectar. Both sexes are prominent singers, with
the males perching on bare branches or power lines in order to project. Orioles are
very apt at adjusting to urban environments, shown in both the US and its native range.
Females are the primary nest builders, while males take an important parental role
once the chicks are hatched. Spot-breasted orioles live sympatrically with other
oriole species, mainly
altimira
and
streak-backed
orioles, and spot-breasted oriole are the least common. It is striking that these
three species have such similar appearance even though they are not very closely related
(Omland and Lanyon, 2000).
- Key Behaviors
- diurnal
- motile
- sedentary
- territorial
- social
Home Range
Spot-breasted orioles are likely territorial, perhaps year round as are many tropical
birds (Hofmann et al. 2008). However, the size of their home range is unknown.
Communication and Perception
As in many tropical birds, both males and females sing (Price, Lanyon and Omland,
2009). Spot-breasted orioles sing year long, at least where it has been observed,
in Florida. Their song is described as a repetitive warbled set of whistled with
lengthy structure and a very appealing tone (similar to that of
altamira orioles
). Notes used for each song are distinct for that particular instance, changing in
tone, frequency, timbre and length each time they sing.
Food Habits
Spot-breasted orioles primarily prey on insects and other arthropods, as well as fruits
and nectar, including nectar of the trees in the genera
Erythrina
,
Caesalpinia
, and
Gliricidia
.
- Animal Foods
- insects
- terrestrial non-insect arthropods
- Plant Foods
- fruit
- nectar
Predation
Nests can be parasitized by
bronzed cowbirds
and have been shown to host fledglings of
giant cowbirds
in populations in Nicaragua.
Ecosystem Roles
Little is known about the role spot-breasted orioles play in their ecosystem. However
it likely pollinates flowers from which it gets nectar, disperses seeds of berries
and other fruits, and impacts populations of insects and other prey.
- Ecosystem Impact
- disperses seeds
- pollinates
- bronzed cowbirds ( Molothrus aeneus )
- giant cowbirds ( Molothrus oryzivorus )
Economic Importance for Humans: Positive
There are no known positive economic impacts of spot-breasted orioles on humans.
Economic Importance for Humans: Negative
There are no known negative economic impacts of spot-breasted orioles on humans.
Conservation Status
Spot-breasted orioles are either common or uncommon throughout their entire geographic
range. They are very accepting of man-made nesting habitats and after accidental
introduction into Florida, they are relatively common in Brevard and Dade Counties.
Other Comments
Based on a 2010 study by Jacobsen, Friedman, and Omland with data from mitochondrial
and nuclear DNA, spot-breasted orioles were most closely related to
white-edged orioles
in a group of tropical orioles known as Clade B.
Additional Links
Contributors
Ian Realo (author), University of Maryland, Baltimore County, Kevin Omland (editor), University of Maryland, Baltimore County, Laura Podzikowski (editor), Special Projects.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- chaparral
-
Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- coastal
-
the nearshore aquatic habitats near a coast, or shoreline.
- suburban
-
living in residential areas on the outskirts of large cities or towns.
- agricultural
-
living in landscapes dominated by human agriculture.
- monogamous
-
Having one mate at a time.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- male parental care
-
parental care is carried out by males
- female parental care
-
parental care is carried out by females
- diurnal
-
- active during the day, 2. lasting for one day.
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- herbivore
-
An animal that eats mainly plants or parts of plants.
- frugivore
-
an animal that mainly eats fruit
- nectarivore
-
an animal that mainly eats nectar from flowers
- omnivore
-
an animal that mainly eats all kinds of things, including plants and animals
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Hofmann, C., T. Cronin, K. Omland. 2008. Evolution of sexual dichromatism 1. Convergent losses of elaborate female coloration in New World orioles ( Icterus spp.). Auk , 125: 778-789.
Jacobsen, F., N. Friedman, K. Omland. 2010. Congruence between nuclear and mitochondrial DNA: Combination of multiple nuclear introns resolves a well-supported phylogeny of New World orioles. Molecular Phylogenetics and Evolution , 56: 419-427.
Jaramillo, A., P. Burke. 1999. New World Blackbirds . Princeton, New Jersey: Princeton University Press.
Omland, K., S. Lanyon. 2000. Reconstructing plumage evolution in orioles ( Icterus ): repeated convergence and reversal in patterns. Evolution , 54: 2119-2133.
Price, J., S. Lanyon, K. Omland. 2009. Losses of female song with changes from tropical to temperate breeding in the New World blackbirds. Proceedings of the Royal Society of London, B. Biological Sciences , 276: 1971-1980.
del Hoyo, J., A. Elliott, D. Christie. 2011. Handbook of Birds of the World . Barcelona, Spain: Lynx Edicions.