List of endemic birds of Borneo explained

The island of Borneo, located in southeast Asia at the southern edge of the South China Sea, is home to one endemic bird family, three endemic bird genera and 61 endemic bird species. All but one of the latter are forest dwellers, with most restricted to the spine of hills and mountains running down the middle of the island. The avian endemism has been shaped by the island's geological history. Borneo sits on a continental shelf. During glacial periods, when water levels were lower, Borneo was linked with other islands on the shelf and with the Malay Peninsula in a large landmass known as Sundaland. This allowed bird species to move freely throughout the region until the waters rose again as the glaciers melted. Separated from their relatives by the sea, some of these species evolved over millennia into the endemics now found on the island. BirdLife International has designated the mountainous central spine of the island as an Endemic Bird Area (EBA) because of the number of endemic species found there, and has further designated several lowland regions and nearby islands as secondary EBAs. Habitat destruction is a major threat to Borneo's endemic birds, as forests are lost to palm oil plantations and timber harvesting.

Geology and geological history

Borneo is an island located in southeast Asia, on the continental shelf at the southern edge of the South China Sea. It lies south of the Philippines, west of Sulawesi, north of Java, and east of Peninsular Malaysia. With an area of 748168km2, it is the world's third largest island. More than half of the island is lowlands, rising to less than 150m (490feet). However, a spine of mountains runs down much of the central portion of the island. These include Mount Kinabalu, which at 4095m (13,435feet) is the tallest mountain between the Himalayas and West Papua. The island is shared by three countries: Indonesia, Malaysia, and Brunei. While the lowlands are the most productive habitat in terms of the number of bird species found there, the mountains are the seat of Borneo's endemism. This is in large part due to the island's geological history.

During the Pleistocene, the world's polar caps repeatedly advanced and retreated, alternately locking vast amounts of water into ice, and releasing it back into the world's oceans. This caused the water level in the oceans to repeatedly rise and fall. During glacial periods, when water levels were at their lowest, much of the Sunda Shelf was exposed. This linked what are now discrete islands (including Borneo, Java, Sumatra, and a host of smaller islands) with the Malay Peninsula in one large landmass known as Sundaland. During periods when the shelf was exposed, birds could move freely across the whole landmass. When the waters rose again, these birds were cut off from their relatives, and evolved in isolation on the various islands. Temperatures were cooler overall during glacial periods, so montane birds (those generally restricted to the slopes of mountains) could move lower and spread across larger areas. During interglacial periods, they retreated to higher elevations and were separated again from other populations, including birds in the lowlands. Studies have shown that some endemic montane species are most closely related to species in Borneo's lowlands, while others are more closely related to montane species on other Sundaland islands.

Endemism and threats

The island is home to a single endemic family: Pityriaseidae, which contains a single endemic genus (Pityriasis) with a single endemic species, the Bornean bristlehead. In addition, the island holds two other endemic genera, both of which are also monotypic: Chlamydochaera (the fruithunter) and Haematortyx (the crimson-headed partridge). Two other monotypic genera formerly considered to be endemic to the island—Chlorocharis and Oculocincta—have since been merged into more widespread genera. Chlorocharis was merged into the large white-eye genus Zosterops after molecular studies showed it nested comfortably within that genus. The same studies showed that Oculocincta was embedded within the smaller white-eye genus Heleia, leading it to be moved as well.

There are 61 endemic bird species on Borneo, according to the taxonomy proposed by the International Ornithologists' Union. Nearly all of these are forest birds; only the dusky munia is not. In all, roughly 10% of Borneo's forest birds are endemic to the island. Of these, 60% are montane species, 30% are found on lower slopes, and 10% are lowland species. However, Borneo's forests are under threat, particularly in the lowlands. Nearly 40% of the island's forests had been completely cleared by 2016, and another 34% had been selectively logged. Some 80% of Kalimantan's forests have been sold to timber concessions. Much of the original lowland forest has been converted to palm oil plantations; these now cover more than 32% of Kalimantan's lowland area. This results in a huge loss of biodiversity. While the original dipterocarp forests are home to more than 220 bird species, for example, palm plantations support only about 14 resident species. Some 80% of Kalimantan's forests have been opened up to timber concessions, even in protected areas. Many highland forests fall into protected areas—including national parks and forest reserves—but such gazetting does not always guarantee true protection, with logging occurring even in those areas.

Endemic Bird Areas

Birdlife International defines Endemic Bird Areas (EBAs) as places where the breeding ranges of two or more range-restricted species—those with breeding ranges of less than 50000km2—overlap. In order to qualify, the whole of the breeding range of at least two range-restricted species must fall entirely within the EBA. Borneo has one such area. The Bornean mountains EBA (157) comprises 130000km2 of mountain ranges in Borneo's interior, at an altitude above 500m (1,600feet) in elevation. These mountains are found in all three countries which share the island. Two of Borneo's three endemic genera are found here; only the Borneo bristlehead is found at lower elevations. In total, 31 range-restricted species occur within this EBA.

BirdLife International has also designated five Secondary EBAs for Borneo: two smaller island groups and three areas on Borneo itself. Secondary EBAs are those which either include the breeding range of only a single range-restricted species, or those which cover only part of a range-restricted bird's breeding area.

List of endemic species

Common namePictureScientific nameHabitatNotes
1Hose's partridgeRhizothera dulitensisHill and lower montane forestdata-sort-value=5 Also known as Dulit partridge.
2Red-breasted partridgeArborophila hyperythraHill dipterocarp forest; lower and upper montane forestdata-sort-value=7 Also known as Bornean partridge.157
3Crimson-headed partridgeHaematortyx sanguinicepsHill dipterocarp forest; lower and upper montane forestdata-sort-value=7 157
4Bulwer's pheasantLophura bulweriHill and lower montane forestdata-sort-value=5
5Bornean peacock-pheasantPolyplectron schleiermacherLowland and hill dipterocarp forestdata-sort-value=4
6Dulit frogmouthBatrachostomus hartertiHill dipterocarp forest; lower montane forestdata-sort-value=6 157
7Bornean frogmouthBatrachostomus mixtusHill dipterocarp forest; lower montane forestdata-sort-value=6
8Bornean swiftletCollocalia dodgeiUpper montane forestdata-sort-value=7 Sometimes considered to be a subspecies of the cave swiftlet or the glossy swiftlet.
9Bornean ground cuckooCarpococcyx radiceusLowland primary dipterocarp and riverine forestdata-sort-value=6
10Mountain serpent eagleSpilornis kinabaluensisUpper montane forestdata-sort-value=5 157
11Whitehead's trogonHarpactes whiteheadiLower and upper montane forestdata-sort-value=6 157
12Mountain barbetPsilopogon monticolaLower and upper montane forestdata-sort-value=7 157
13Golden-naped barbetPsilopogon pulcherrimusUpper montane forestdata-sort-value=7 157
14Bornean barbetPsilopogon eximiusLower and upper montane forestdata-sort-value=7 157
15Brown barbetCaloramphus fuliginosusLowland dipterocarp forest and lower hill forest, swamp forest and kerangas forestdata-sort-value=7 Sometimes known as the Bornean brown barbet.
16White-fronted falconetMicrohierax latifronsLowland dipterocarp forestdata-sort-value=6 s098
17Hose's broadbillCalyptomena hosiiHill dipterocarp forest; lower montane forestdata-sort-value=6 157
18Whitehead's broadbillCalyptomena whiteheadiLower and upper montane forestdata-sort-value=7 157
19Bornean banded pittaHydrornis schwaneriLowland and hill dipterocarp forestdata-sort-value=7
20Blue-headed pittaHydrornis baudiiLowland dipterocarp forestdata-sort-value=5
21Black-crowned pittaErythropitta ussheriLowland dipterocarp forestdata-sort-value=6
22Blue-banded pittaErythropitta arquataHill and lower montane forest, particularly bamboo grovesdata-sort-value=7
23Bornean bristleheadPityriasis gymnocephalaLowland and hill dipterocarp forestdata-sort-value=6
24Bornean whistlerPachycephala hypoxanthaLower and upper montane forestdata-sort-value=7 157
25Black orioleOriolus hosiiLower and upper montane forestdata-sort-value=6 157
26Bornean black magpiePlatysmurus aterrimusLowland forest and swamp forest data-sort-value=7 Formerly considered to be a subspecies of the black magpie; split in 2021.
27Bornean green magpieCissa jefferyiLower forestdata-sort-value=7
28Bornean treepieDendrocitta cinerascensHill dipterocarp forest; lower and upper montane forestdata-sort-value=7
29Charlotte's bulbulIole charlottaeLowland and hill dipterocarp and peat swamp forestsdata-sort-value=6 Sometimes considered to be a subspecies of the buff-vented bulbul.
30Bornean bulbulRubigula montisLower and upper montane forestdata-sort-value=7
31Cream-eyed bulbulPycnonotus pseudosimplexLowland and hill dipterocarp and peat swamp forests; lower montane forestsdata-sort-value=7
32Pale-faced bulbulPycnonotus leucopsUpper montane forestdata-sort-value=7 Sometimes considered to be a subspecies of the flavescent bulbul.
33Bornean stubtailUrosphena whiteheadiHill dipterocarp forest; lower and upper montane forestdata-sort-value=7 157
34Friendly bush-warblerLocustella accentorUpper montane forestdata-sort-value=7 157
35Chestnut-crested yuhinaStaphida everettiHill dipterocarp forest; lower and upper montane forestdata-sort-value=7 157
36Pygmy white-eyeHeleia squamifronsHill dipterocarp forest and lower montane forestdata-sort-value=7 157
37Mountain blackeyeZosterops emiliaeUpper montane forestdata-sort-value=7 157
38Meratus white-eyeZosterops meratusensisMontane forestdata-sort-value=7
39Bare-headed laughingthrushMelanocichla calvaLower and upper montane forestdata-sort-value=7 157
40Black-throated wren-babblerTurdinus atrigularisLowland dipterocarp forestdata-sort-value=6
41Black-browed babblerMalacocincla perspicillataProbably lowland forestdata-sort-value=8 Rediscovered in 2020, more than 170 years after the only specimen was collected.s099
42Mountain wren-babblerGypsophila crassaLower and upper montane forestdata-sort-value=7 157
43Bornean wren-babblerPtilocichla leucogrammicaLowland dipterocarp and peat swamp forests; kerangas forestdata-sort-value=5
44Chestnut-hooded laughingthrushPterorhinus treacheriHill dipterocarp forest; lower and upper montane forestsdata-sort-value=7
45Everett's thrushZoothera everettiLower and upper montane forestdata-sort-value=6 157
46FruithunterChlamydochaera jefferyiLower and upper montane forestdata-sort-value=7 157
47White-crowned shamaCopsychus stricklandiiLowland and hill dipterocarp and peat swamp forests; lower montane forestdata-sort-value=7 Sometimes considered to be a subspecies of the white-rumped shama.
48Dayak blue flycatcherCyornis montanusMontane forestdata-sort-value=7 Sometimes considered to be a subspecies of the hill blue flycatcher (aka Javan blue flycatcher).157
49Meratus blue flycatcherCyornis kadayangensisMontane forestdata-sort-value=7 157
50Bornean blue flycatcherCyornis superbusLowland and hill dipterocarp forestdata-sort-value=7
51Crocker jungle flycatcherCyornis ruficrissaMontane forestdata-sort-value=9 Not recognised by IUCNSometimes considered to be a subspecies of the Philippine jungle flycatcher.157
52Eyebrowed jungle flycatcherVauriella gularisLower and upper montane forestdata-sort-value=7 157
53Bornean forktailEnicurus borneensisStreams in lower to upper montane forestdata-sort-value=9 Not recognised by IUCNSometimes considered to be a subspecies of the white-crowned forktail.
54Bornean whistling thrushMyophonus borneensisLower and upper montane forestdata-sort-value=7
55Bornean leafbirdChloropsis kinabaluensisLower and upper montane forestdata-sort-value=7
56Yellow-rumped flowerpeckerPrionochilus xanthopygiusLowland, hill and lower montane forestdata-sort-value=7
57Spectacled flowerpeckerDicaeum dayakorumLowland and hill dipterocarp forestdata-sort-value=8 Described to science in 2019.
58Black-sided flowerpeckerDicaeum monticolumHill dipterocarp forest; lower and upper montane forestdata-sort-value=7 157
59Bornean spiderhunterArachnothera everettiLowland, hill, and lower montane forestdata-sort-value=7 Sometimes considered to be a subspecies of streaky-breasted spiderhunter.
60Whitehead's spiderhunterArachnothera juliaeLower and upper montane forestdata-sort-value=7 157
61Dusky muniaLonchura fuscansScrub, gardens, grasslands, and rice paddiesdata-sort-value=7

See also

Citations

References

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "List of endemic birds of Borneo".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.