How the Urban Jungle Drives Evolution: 2. Javan Mynas

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A pair of Javan Mynas in my kitchen – video grab.

On 5th August 2018 I managed to video-document a pair of Javan Mynas (Acridotheres javanicus) sneaking into my kitchen to steal food (see video below). This followed a few weeks of chasing them away after their daily forays into the kitchen LINK. Only closing the kitchen window and door kept them away.

Invading houses to seek food, just like the Long-tailed macaques (Macaca fascicularis) have been doing for years, shows that these Javan Mynas have indeed adapted well to city life in Singapore. After all, what more are they capable of… I suppose time will tell.

A group of Javan Mynas resting on top of a front gate in the neighbourhood.
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The Javan Myna is presumed to have descended from cage-birds originating in Java. A feral population was present in Singapore as far back as 1925 (Wang & Hails, 2007). Through the years its population has increased so much so that currently it is the commonest resident bird in Singapore.

Why is the Javan Myna so successful in our urban environment?

Javan Myna with oil palm fruit – photo by Johnny Wee.

It is an opportunistic feeder, so finding food is no problem. It eats most fruits, from soft fleshy noni (Morinda citrifolia) to the hard and fibrous oil palm fruits (Elaeis guineensis). It also takes honey from flowers as well as flower petals.

Javan Myna caught a Spotted House Gecko – photo by Chan Yoke Meng.

Its invertebrate food includes millipedes, earthworms, various insects and their larvae as well as spotted house gecko (Gekko monarchus) that is plentiful. In hawker centres and open-air restaurants, it boldly takes leftover food even before diners leave the table. Now it even enters homes to steal food.

It does not fear humans. You can approach it within half a meter before it flies off. With patience you can even hand feed the bird.

Javan Myna waiting for arthropods to be exposed when someone is weeding the garden.

Whenever my helper or myself is working in the garden weeding or working in the compost pit, there will always be a pair waiting for an opportunity to pick on insects, earthworms, etc. that I disturb or unearth LINK. Similarly, there will always be a few Javan Mynas around whenever grass cutters are at work. This myna will also raid food placed inside cages meant for the cage-bird/s LINK. It has also been known to move all over a dog, even probing its thick hairs in order to pick ticks off the dog’s nose.

Javan Mynas associating with Wild Boars – photo by Adrian Lim.

In rural areas Javan Mynas commonly follow foraging wild boars or even water buffaloes, to catch insects disturbed by these animals moving around.

Javan Myna is also bold as well as aggressive. It has been known to harass cats and dogs, to the extent of stealing food meant for the latter. It even harass the large Clouded Monitor Lizard (Varanus nebulosus).

Javan Mynas in a fight – photo by KC Tsang.

Javan Mynas can be very noisy, especially when rival gangs fight for the possession of food, maintain territorial space, etc. LINK and LINK.

These birds will nest in whatever available space or cavity it can find… under the roof of buildings, in electrical boxes, etc.

Javan Myna anting with millipede – photo by Kwong Wai Chong.

This is one of the easiest bird to witness anting, either with ants or with a millipede.

Crested Goshawk caught a Javan Myna – photo by Jonathan Kuah.

Because Javan Myna is so common, many are preyed upon by raptors.

There are still much to learn about the behavior of this myna but because it is a common bird, birdwatchers and photographers generally ignore it.

YC Wee
Singapore
5th August 2018

Reference:
Wang, L.K. & C. J. Hails, 2007. An annotated checklist of birds of Singapore. Raffles Bulletin of Zoology, Supplement 15: 1-179.

Note: This series of posts is inspired by Menno Schilthuizen’s book “Darwin Comes to Town: How the Urban Jungle Drives Evolution” – 2018, Quercus Editions Ltd., London. 352pp. – LINK.

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