Anthreptes malacensis

Geographic Range

Anthreptes malacensis , more commonly known as the brown-throated sunbird, has a very large geographic range this is concentrated in the Southeast region of the world (Red List, 2016). This species is native to Cambodia, China, Indonesia, Malaysia, Philippines, Thailand, Vietnam, Singapore and other Southeastern Asian territories (Red List, 2016).

• Biogeographic Regions
• oriental oriental
  • native native

Habitat

Southeast Asia, the natural home of Anthreptes malacensis , is characterized by a tropical climate that is hot and humid all year long, resulting in large areas of rainforests. It is in those rainforests that Anthreptes malacensis make their homes (Cohen et al. 1994). Sunbirds are found in lower elevations that are close to sea-level, densely populating island and coastal areas (Cohen et al. 1994). These birds are commonly found in rainforests, mangroves, city parks and family gardens (National Parks, 2013). They populate both urban and provincial areas of Southeast Asia, and are often seen visiting flowering trees and bushes in the early morning (National Parks, 2013).

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest
• rainforest rainforest

• Other Habitat Features
• urban urban
• suburban suburban
• agricultural agricultural
• riparian riparian
• estuarine estuarine

Physical Description

Both male and female Anthreptes malacensis have a characteristic brown throat, but otherwise the two sexes look very different. In order to attract a mate, a male Anthreptes malacensis has a green metallic head and neck, dark purple wings that are often spotted with red and blue, and a bright yellow stomach (National Parks, 2013). Females are a dull, olive green color with slightly darker wings (National Parks, 2013). Males are also slightly larger, their body length averaging around 16 cm while females are approximately 13 cm (Cheke et al. 2001). Sunbirds are nectar feeders, so they have evolved to have thin, down-curved beaks with brush-tipped tubular tongues (Birds of the World, 2018). Their long tongues can curl inwards, so when they drink nectar, none is spilled. Their wingspan is relatively short, averaging around 19 cm, so that the sunbird’s flight is fast and direct (Birds of the World, 2018).

• Other Physical Features
• endothermic endothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• male larger
• sexes colored or patterned differently
• male more colorful

Reproduction

Sunbirds are monogamous, remaining paired throughout the breeding season and while raising their young (Wolf et al. 1974). When males are ready to begin breeding, they establish their territory and begin to interact with unmated females. Male Anthreptes malacensis don’t typically exhibit lekking behavior, instead relying on their bright colors to attract a mate (Wolf et al. 1974).

• Mating System
• monogamous monogamous

Anthreptes malacensis breed throughout the year, as they reside in the equatorial region of the world that receives high levels of rainfall throughout the year, resulting in an abundance of insects for the growing young to feed upon (Wolf et al. 1974). After mating, the female sunbird solely builds the nest, typically taking 10-16 days to complete (Wolf et al. 1974). Nests are built in low bushes 1-2 meters above the ground and are composed of dry plants and grasses, supported primarily by spider webs scavenged by the female (Wolf et al. 1974). The nests are built in domes shapes with a single side entrance. While the females build their nests, males hover close by, often chasing away other birds and protecting the nest and nearby nectar supplies (Wolf et al. 1974). After the nest is complete, females lay 1-3 eggs and solely incubate them for an average of 18 days. During the nesting period, both parents feed the young a mixed diet of insects and nectar (Wolf et al. 1974).

• Key Reproductive Features
• iteroparous iteroparous
• year-round breeding year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Both male and female Anthreptes malacensis take care of their young, though they take on different roles. Female sunbirds solely build the nest and incubate the eggs while their mates perch nearby and protect the territory (Wolf et al. 1974). After the young hatch, both parents feed them. Females fly further from the nest to search for insects while males stay within the territory, often feeding the hatchlings nectar (Wolf et al. 1974). After about 12 days after hatching, the fledglings can feed from nearby flowering plants (Wolf et al. 1974). Fledglings do not gain full independence until they are a few weeks old, remaining with their parents until they are ready to leave the territory (Wolf et al. 1974).

• Parental Investment
• altricial altricial
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male

Lifespan/Longevity

A general trend in nature is the correlation between organismal size and lifespan. Typically, smaller animals live shorter lives, as is the case with Anthreptes malacensis . These birds lead fast lifestyles as they expend a lot of their energy on fast flight, resulting in a lifespan of about 7 years (Gan, 2005). Sunbirds live about the same amount of time in captivity as they do in the wild under good care (Gan, 2005).

Behavior

Anthreptes malacensis share many general behavioral characteristics with the larger sunbird family. All sunbirds are non-migratory and are active during the day (Sunbird Facts, 2018). Sunbirds typically reside in the same general area for most of their lifetime, choosing to travel short distances when their food resources are depleted. To preserve their energy, Anthreptes malacensis undergo torpor at night where they regulate a decreased internal body (Sunbird Facts, 2018). This allows them to use extra energy to sustain their fast and direct flight. Sunbirds tend to live in pairs or small groups, as male birds are often aggressive towards any other birds that they perceive as encroaching on their territory (Sunbird Facts, 2018). Anthreptes malacensis are monogamous birds and mate for life. During mating and hatching times, males exhibit protective behavior while the female birds build nests and prepare for their young. However, both parents raise and feed their offspring once they have hatched (Wolf et al. 1974). Because sunbirds are nectar feeders, they play a key role in pollination as they fly from one plant to the next, perching on branches to better access hidden nectar (Bird Ecology, 2009). Sunbirds lead fast lifestyles, meaning that they spend most of their time searching for food to meet their metabolic needs. Anthreptes malacensis are proud birds. Though they do not demonstrate any lekking behavior when finding a mate, the bright colors of a male sunbird are designed to attract a female (Cheke et al. 2001). They also are commonly seen looking at their reflection in mirrors or windows. Sunbirds are also known to perch from a prominent vantage point and sing, even though they are known to have unpleasant, chirping calls (Cheke et al. 2001).

• Key Behaviors
• arboreal arboreal
• flies
• glides
• diurnal diurnal
• motile motile
• sedentary sedentary
• daily torpor
• solitary solitary
• territorial territorial
• social social

Home Range

The home range has not been quantified for Anthreptes malacensis , but has been roughly equated to cover the extent of Southeast Asia.

Communication and Perception

Anthreptes malacensis communicate through behavior and call, though they primarily rely on their song. Sunbirds, and particularly male brown-throated sunbirds, are aggressive and guard their territory from other intraspecific competition (Cheke et al. 2001). They accomplish this with high pitched, piercing calls that alert other birds that they are encroaching on another male’s territory (Cheke et al. 2001). Female sunbirds are not considered threats in a male’s territory, a reality that they present through bizarre behavior that is characterized by wing-quivering and tail-spreading that evokes an image of subordination (Cheke et al. 2001). Anthreptes malacensis communicate with loud, incessant chirps for long periods at a time. Different calls have been documented that exhibit the range of the sunbird’s call, ranging from rapid nasal chatter, to long calls that are drawn out for over 10 seconds in a single breath (Cheke et al. 2001). The variety of vocalization indicates many different things, including arrival at foraging sites, defense of territories, advertisement to mates, and communication between other animals (San Diego Zoo, 2018).

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Anthreptes malacensis rely on an insect and nectar heavy diet. Their beaks are long and thin with a tubular tongue adapted to the flowering plants of Southeast Asia (Sunbirds 2018). Their beaks are also characterized by fine serrations that allow the birds to grip insects (Sunbirds 2018). Instead of hovering, Anthreptes malacensis perch on nearby branches when feeding from flowers in order to conserve energy (Bird Ecology, 2009). Sunbirds also feed from a range of flowering plants, and have adapted different ways to feed when they are inhibited by the flower’s mechanism. For example, sunbirds probe the base petals of wide hibiscus flowers to access the nectar within (Bird Ecology, 2009). Anthreptes malacensis prey on insects native to Southeast Asia, including the weaver ant, Oecophylla smaragdina , and the tropical firefly, Luciolinae peroptyx . Brown-throated sunbirds prey on insects by scavenging the tropical foliage and the top of low shrubs (Bird Ecology, 2009).

• Primary Diet
• carnivore carnivore
  • insectivore insectivore
• herbivore herbivore
  • nectarivore nectarivore
• omnivore omnivore

• Animal Foods
• insects
• terrestrial non-insect arthropods
• terrestrial worms

• Plant Foods
• fruit
• nectar
• pollen

Predation

The most common predator of Anthreptes malacensis , and specifically of their eggs and young, are snakes such as white-lipped pit vipers ( Trimeresurus albolabris ) and bronze tree snakes ( Dendrelaphis caudolineatus ) (Cheke et al. 2001). Sunbird nests hang off bushes and branches relatively low to the ground, making the nests easy to access by land predators. This predation may have driven the evolution of the phenotypic appearance of the bird nests, as female sunbirds build their nest as if to camouflage them (Cheke et al. 2001). Other predation of fledgling Anthreptes malacensis is by the parasitic cuckoo birds, Asian koels, that eject the sunbird young from nests to make room for their own offspring (Cheke et al. 2001). Environmental factors such as monsoon season and lack of nearby resources also result in the loss of life of sunbirds.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Pollinators, such as Anthreptes malacensis , play key roles in their ecosystems. Because of their nectar heavy diet, these sunbirds are vital in the dispersion of seeds that results in the propagation of multiple organisms that compose an ecosystem (Cheke et al. 2001). Brown throated sunbirds also feast on insects, which keeps the population of insects in Southeast Asia in check (Bird Ecology, 2009). Without sunbirds, the ecosystem of Southeast Asia would be greatly unbalanced.

• Ecosystem Impact
• disperses seeds
• pollinates

Economic Importance for Humans: Positive

Anthreptes malacensis have a positive economic impact on humans through their roles as pollinators (Cheke et al. 2001). Sunbirds eat nectar from a variety of flowering plants, some of which have economic value as crops. Because of this, brown throated sunbirds help with the dispersal of seeds and the successful propagation of these valuable crops (Cheke et al. 2001). Overall, this contribution to pollination is invaluable to an ecosystem and to the promotion of biodiversity.

• Positive Impacts
• pollinates crops

Economic Importance for Humans: Negative

Through the same mechanism that makes sunbirds have positive economic importance to humans is also responsible for their adverse effects on both the environment and humans. In many documented scenarios, sunbird pollination activity has resulted in the introduction of foreign organisms to delicate ecosystems. For example, Anthreptes malacensis is to blame for the infestation of local cocoa plants in Asia by mistletoe (Cheke et al. 2001). Most of the crop was ruined, resulting in profit loss for the framers and the surrounding community. Another example of the detrimental side effects of sunbird eating habits is seen in vineyards dotted throughout Southeast Asia. Anthreptes malacensis have been documented puncturing the thin skin of grapes and other vine fruit and sucking out the juices, making the plants unfit for human consumption (Cheke et al. 2001).

• Negative Impacts
• crop pest

Conservation Status

Though seven species of sunbirds are considered endangered due to habitat loss as a result of deforestation from human activities, Anthreptes malacensis are not considered endangered (Sunbird Facts, 2018). The brown throated sunbird is considered common in many parts of Southeast Asia and is described as stable (Red List, 2016). Because these birds inhabit such a large range and have a large population size, Anthreptes malacensis are evaluated as Least Concern by the Red List organization (Red List, 2016).

Additional Links

Encyclopedia of Life

Contributors

Lilleana Rogers (author), Colorado State University, Peter Leipzig (editor), Colorado State University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

Cheke, R., C. Mann, R. Allen. 2001. Sunbirds: a guide to the sunbirds, flowerpeckers, spiderhunters and sugarbirds of the world. . London, UK: Christopher Helm.

Cohen, J., C. Small. 1994. "Population and Elevation in Southeast Asia" (On-line). Accessed February 20, 2018 at https://www.ldeo.columbia.edu/~small/Pop/HypsoDemo/S.E.Asia.html .

Gan, J. 2005. Sunbird Longevity. Wetlands , 9: 10-11.

Wolf, L., J. Wolf. 1974. MATING SYSTEM AND REPRODUCTIVE BIOLOGY OF MALACHITE SUNBIRDS . New York: Syracuse Univeristy. Accessed February 27, 2018 at https://sora.unm.edu/sites/default/files/journals/condor/v078n01/p0027-p0039.pdf .

2018. "Anthreptes malacensis" (On-line). Lee Kong Chiang Natural History Museum. Accessed February 08, 2018 at https://lkcnhm.nus.edu.sg/dna/organisms/details/538 .

2013. "Anthreptes malacensis" (On-line). National Parks: Flora and Fauna Web. Accessed February 20, 2018 at https://florafaunaweb.nparks.gov.sg/special-pages/animal-detail.aspx?id=783 .

2016. "Anthreptes malacensis" (On-line). Red List. Accessed February 14, 2018 at http://www.iucnredlist.org/details/103792612/0 .

2016. "Anthreptes simplex" (On-line). Red List. Accessed February 14, 2018 at http://www.iucnredlist.org/details/22717611/0 .

2016. "Asian Sunbirds" (On-line). Birds of the World. Accessed February 20, 2018 at http://carolinabirds.org/HTML/Sunbird_Asian.htm .

2018. "Beautiful Sunbird" (On-line). San Diego Zoo. Accessed March 26, 2018 at http://animals.sandiegozoo.org/animals/beautiful-sunbird .

2017. "Brown-throated Sunbird: Anthreptes malacensis" (On-line). The Internet Bird. Accessed February 08, 2018 at https://www.hbw.com/ibc/species/brown-throated-sunbird-anthreptes-malacensis .

2003. "Plain-throated Sunbird" (On-line). Avibase- the World Bird Database. Accessed February 08, 2018 at https://avibase.bsc-eoc.org/species.jsp?avibaseid=7F96C52A42C0C7A7 .

2018. "Sunbird Facts" (On-line). Accessed March 20, 2018 at http://www.softschools.com/facts/animals/sunbirds_facts/2090/ .

2017. "Sunbird" (On-line). Encyclopedia of Life. Accessed February 08, 2018 at http://eol.org/data_objects/31548244 .

2018. "Sunbirds" (On-line). Accessed February 27, 2018 at http://science.jrank.org/pages/6607/Sunbirds.html .

2009. "What do Sunbirds Eat?" (On-line). Bird Ecology. Accessed February 27, 2018 at http://www.besgroup.org/2007/02/01/what-do-sunbirds-eat/ .