Wetlands of Colombo: Thalangama Lake

A little way past Battaramulla, Colombo, lies a small, serene reservoir surrounded by a quiet green neighbourhood. Built by King Parakramabahu VI (1412 - 1467 AD) as a bathing spot for his royal elephants, it also functioned as an irrigation reservoir (wæwa) for acres of paddy cultivation downstream - a system that lasts even to this day.

Thalangama Lake. Source: Google Maps 

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The most commonly used approach route is the obviously-named Lake Road, branching off D.P. Wijesinghe Mawatha in Pelawatta. As you travel down the winding road, you encounter stretches of green paddy fields dotted with cattle and a few domestic buffaloes. Cutting a sharp curve, and passing the sluice outlet, the road opens up and you find yourself moving eastwards along the bund of the reservoir: its calm waters on your right, and a basin of paddy fields down a slope to your left.

Thalangama Lake, from the eastern end of the bund. The signboards (far right) mark the western end.

Closer to the bund, the lake surface is more or less clear, apart from the occasional raft of lotuses (Nelumbo nucifera) or water lilies (Nymphaea spp). Nestled among them are a variety of smaller aquatic plants, which, depending on the time, may also be accompanied by invasive plants - dense clumps of  water hyacinths (Eichornia crassipes) and rafts of Salvinia, which grow thicker further down the lake.

On open waters you might spot pairs or small flocks of Little Grebes, and sometimes Cotton Teals. There are several cormorants swimming around, diving occasionally for fish, including the relatively uncommon Oriental Darter.

You turn a corner and head down the eastern side of the lake. Pacing on lily pads and occasionally swimming are Pheasant-tailed Jacanas and Common Moorhens. Purple Coots and White-breasted Waterhens are commonly seen closer to the banks, too - and sometimes they’re accompanied by adorably fuzzy chicks the colour of soot. My sister claims to have seen an elusive Cinnamon Bittern in the thick undergrowth by the lake edge.

White-breasted Waterhen chick

Common Moorhen

Indian Pond Heron 

The road down the eastern border is a residential lane with nice suburban bungalows and big gardens, but for the most part canopied with lush trees, on which any number of passerine birds could be seen - from babblers, bulbuls and sunbirds to migratory flycatchers. Endemic Lesser Sri Lanka Flamebacks and Sri Lanka Small Barbets can be seen popping in and out of nesting holes, while Rose-ringed Parakeets screech overhead. The whistled call of the Indian Pitta, another winter migrant, can be heard in the mornings and evenings.

Asian Brown Flycatcher 

Halfway towards the southern end of the lake, the silt bed rises close enough to support groves of trees on “islands”. These dense groves support colonies of roosting birds - egrets, cormorants, herons and storks - and provide nesting sites during the breeding season.

Little Cormorant 

Eventually, the silt overtakes the lake, turning it into a swamp, overrun by water hyacinths, reeds, paddy, stands of taro plants and pandanus groves. Here, flocks of Purple Coots feed and fight for territory, Lesser Whistling Teals standing by placidly. In the migrant season, a birder with a good eye can spot Pintail Snipes feeding in the grasslands and nearby fields and meadows. The tall grasses provide a good hunting spot for Purple Herons, who can stand for ages as still as a statue, their streaked throats breaking up their outlines, allowing them to blend in. 

Pandanus grove

Up in the airspace, Brahminy Kites are the main predators, alongside Shikras, and both can be harassed by crows. During the migrant season, Blue-tailed Bee-eaters and Barn Swallows fly low over the waters, occasionally pausing to rest on dead branches. Swifts do the same, fluttering above, but never seeming to land. The Pied Kingfisher is seen hovering above the water, sometimes plummeting in for a catch, but not always succeeding.

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A list of bird species I’ve been able to observe in and around Thalangama Lake during my five visits so far (in Clements’ order of classification). This list will gradually increase upon further visits:

1. Lesser Whistling Teal (Dendrocygna javanica) - resident
2. Cotton Teal (Nettapus coromandelianus) - uncommon resident
3. Little Grebe (Tachybaptus ruficollis) - resident
4. Feral Pigeon (Columba livia) - common resident
5. Spotted Dove (Streptopelia chinensis) - common resident
6. Green Imperial Pigeon (Ducula aenea) - resident
7. Greater Coucal (Centropus sinensis) - resident
8. Asian Koel (Eudynamys scolopacea) - common resident
9. Asian Palm Swift (Cypsiurus balasiensis) - resident
10. Little Swift (Apus affinis) - resident
11. White-breasted Waterhen (Amaurornis phoenicrurus) - common resident 
12. Purple Coot (Porphyrio porphyrio) - resident
13. Watercock (Gallicrex cinerea) - scarce resident
14. Common Moorhen (Gallinula chloropus) - uncommon resident
15. Black-winged Stilt (Himantopus himantopus) - common winter migrant
16. Red-wattled Lapwing (Vanellus indicus) - common resident
17. Pheasant-tailed Jacana (Hydrophasianus chirurgus) - resident
18. Pintail Snipe (Gallinago stenura) - winter migrant
19. Whiskered Tern (Chlidonias hybrida) - common winter migrant
20. Asian Openbill (Anastomus oscitans) - resident
21. Painted Stork (Mycteria leucocephala) - resident
22. Oriental Darter (Anhinga melanogaster) - uncommon resident
23. Little Cormorant (Microcarbo niger) - common resident
24. Indian Cormorant (Phalacrocorax fuscicollis) - common resident
25. Spot-billed Pelican (Pelecanus philippensis) - resident
26. Cattle Egret (Bubulcus ibis) - common resident 
27. Grey Heron (Ardea cinerea) - resident
28. Purple Heron (Ardea purpurea) - resident
29. Little Egret (Egretta garzetta) - common resident
30. Indian Pond Heron (Ardeola grayii) - common resident
31. Black-crowned Night Heron (Nycticorax nycticorax) - uncommon resident
32. Yellow Bittern (Ixobrychus sinensis) - uncommon resident/winter migrant
33. Black-headed Ibis (Threskiornis melanocephalus) - resident
34. Shikra (Accipiter badius) - common resident
35. Brahminy Kite (Haliastur indus) - common resident
36. Oriental Honey-buzzard (Pernis ptilorhynchus) - scarce resident/winter migrant
37. Common Kingfisher (Alcedo atthis) - resident
38. Stork-billed Kingfisher (Pelargopsis capensis) - uncommon resident
39. White-throated Kingfisher (Halcyon smyrnensis) - common resident
40. Pied Kingfisher (Ceryle rudis) - resident
41. Blue-tailed Bee-eater (Merops philippinus) - common winter migrant 
42. Sri Lanka Small Barbet (Psilopogon rubricapillus) - common endemic
43. Brown-headed Barbet (Psilopogon zeylanicus) - common resident
44. Lesser Sri Lanka Flameback (Dinopium psarodes) - common endemic
45. Rose-ringed Parakeet (Psittacula krameri) - common resident 
46. Alexandrine Parakeet (Psittacula eupatria) - uncommon resident
47. Black-naped Oriole (Oriolus xanthornus) - resident
48. Ashy Woodswallow (Artamus fuscus) - uncommon resident
49. Common Iora (Aegithina tiphia) - resident
50. White-bellied Drongo (Dicrurus caerulescens) - resident
51. Indian Paradise-flycatcher (Terpsiphone paradisi) - winter migrant
52. Brown Shrike (Lanius cristatus) - common winter migrant
53. House Crow (Corvus splendens) - common resident
54. Large-billed Crow (Corvus macrorhynchos) - resident
55. Common Tailorbird (Orthotomus sutorius) - common resident
56. Ashy Prinia (Prinia socialis) - resident
57. Plain Prinia (Prinia inornata) - resident
58. Zitting Cisticola (Cisticola juncidis) - resident
59. Barn Swallow (Hirundo rustica) - common winter migrant
60. Sri Lanka Swallow (Cecropis hyperythra) - endemic
61. Red-vented Bulbul (Pycnonotus cafer) - common resident
62. White-browned Bulbul (Pycnonotus luteolus) - common resident 
63. Oriental White-eye (Zosterops palpebrosus) - resident
64. Yellow-billed Babbler (Turdoides affinis) - common resident 
65. Common Myna (Acridotheres tristis) - common resident
66. Asian Brown Flycatcher (Muscicapa dauurica) - winter migrant
67. Indian Robin (Copsychus fulicatus) - resident
68. Oriental Magpie Robin (Copsychus saularis) - common resident
69. Tickell’s Flowerpecker (Dicaeum erythrorhynchos) - common resident 
70. Purple-dumped Sunbird (Leptocoma zeylonica) - common resident
71. Loten’s Sunbird (Cinnyris lotenius) - resident
72. Baya Weaver (Ploceus philippinus) - resident
73. White-rumped Munia (Lonchura striata) - resident
74. Scaly-breasted Munia (Lonchura punctulata) - resident

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While the main attraction of Thalangama is its birdlife, the endemic Purple-faced Langurs (Semnopithecus vetulus) should not be missed, as they swing from tree to tree uttering their hoarse, booming calls. A massive water monitor - or two - is not an improbable sight, whether it’s laboriously swimming through the lake or lumbering across the road. Brightly-coloured butterflies, dragonflies and damselflies are among the commonly observed insect species. 

Purple-faced Langur

Thalangama is a quiet and beautiful birding “patch”, a remnant of the once-extensive wetlands that used to span across Colombo, especially the region now known as Kotte. It is officially protected as part of the Sri Jayawardenapura Kotte Sanctuary, and day-to-day maintenance is carried out by the Thalangama Wetland Watch, a non-profit community organisation that regularly clears the lake of any garbage and invasive plants, while also raising awareness.

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I’ve been to Thalangama Lake five times so far, and will definitely visit it more. It’s a good spot for a quiet family outing - like my first three visits, where my sisters and I tried to spot and observe as many birds as possible. It’s also a nice place for a date - yes, a little picnic would be cute, but I’m talking about nerds juggling backpacks, binoculars, plus notebook and camera, with a spotting scope and a tripod to boot! 

What this place isn’t really meant for are loud and raucous gatherings of people generally disrupting the peace of the area. What it doesn’t want is people tossing garbage or otherwise polluting its waters. 

That said, you don’t have to be a birder or any kind of naturalist to enjoy Thalangama Lake. All you’d need is a keen eye and quiet mind to simply take a walk with Nature - and share it with friends or loved ones.

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Interesting links to check out:

Thalangama Wetland Watch

Gehan de Silva Wijeyeratne records 70 bird species in a single morning at and around Thalangama Lake