An earlier post of a sleeping Common Tailorbird (Orthotomus sutorius) that looked like a tiny ball of feathers has spawned another report on sleeping birds by Eddie Lee. This time we have a few images of the tailorbird in dreamland as well as those of the Olive-backed Sunbird (Cinnyris jugularis):

“I first noticed that the Olive-backed Sunbirds spent the night perching on tree branches a while ago, but didn’t pay much attention to them.

“Then on 28th May 2006 I saw a lone male Olive-backed perching on a tree branch under cover of darkness, presumably spending the night till daybreak. This time I was armed with a camera and took some shots of it at arm’s length distance (left). Incidentally the flash which illuminated the branches did not seem to disturb the bird at all. It continued with its seemingly deep sleep. The bird was seen on a few more occasions after this encounter and subsequently failed to return.

“On 25th March 2007 I caught sight of a pair of Common Tailorbird doing the same on a different type of plant. Managed to shoot some pictures. Again on 5th April, but only a single tailorbird returned to roost. The bird was once again photographed on 22nd July.

“All the pictures were taken between 8-9 pm (top). As I only visit the place during Sunday nights, I can only presume that the same bird returned to the same plant every night until recently when it was no longer to be seen.”

Most birders take it for granted that diurnal birds sleep at night. And that nocturnal birds do so during the day. We do look for sleeping nocturnal birds, especially owls but how many birdser look for sleeping diurnal birds at night? We are familiar with masses of roosting birds but individual birds? With this post we know that birds take different postures sleeping. Unlike the tailorbird, the sunbird does not tug its head under its wing. Both sleep while perched on a branch. I am sure there are birds that sleep on the ground.

It is hoped that photographer who are fascinated with birds will keep a look out for sleeping birds and share their images.

Yes, what does a tailorbird do at night? Or all diurnal birds for that matter. Why, some but not all sleep. Many waders feed at night when the mudflats are exposed due to low tide. So they cannot afford to sleep. Other birds feed at night because it is safer to do so when many predators are asleep.

Many birds sleep with the head turned and resting on the shoulder and the bill tucked among fluffed up plumage of the back. They may sleep standing up of sitting with the feet locked on the perch. Some sleep clinging to tree trunks with their toe nails eg. treecreeper.

Where birds sleep is important.

Some species come together in communal roosts to sleep, either the year round or only during the non-breeding season. Snuggling together helps to significantly reduce heat loss. Hole nesters roost inside their cavities. Other birds sleep in groups or alone. They usually sleep under cover of vegetation.

But this apparently was not so with the tailorbird.

In April 2007, Ng Bee Choo and Morten Strange were holidaying in Taman Negara, Malaysia. On their way to dinner one night, they stumbled on a small ball of feathers attached to the leaflets of a palm sapling. On recognising that it was a sleeping bird, Bee Choo rushed back to her room to get a camera. Not wanting to disturb the sleeping bird, she did not switch on the flash.

Her image of the sleeping tailorbird is shown above. It shows a smallish ball of feathers, the two feet locked on the base of the palm leaflet. The head of the bird was tightly tugged under a wing such that the bill was totally out of sight. The feathers were fluffed. These are the ways birds keep warm.

At one end of the ball of feathers was a small, narrow tail, distinctly obvious. The rufous crown and one of the black shoulders can be distinguished.

Yes, birds do sleep. Like all warm-blooded animals, they sleep when they are tired and full of food. After all, most birds cannot see well at night. Only a few, like the owls, have large eyes specially adapted for night vision. When they sleep their toes automatically lock tight, thus preventing them from falling while asleep. The above image of the Common Iora (Aegithina tiphia) snug in its nest, was taken by Cheong Weng Chun at night. Although it shows the back view, I am sure the bird was fast asleep. Many species like mynas, crows, starlings, Pacific Swallow (Hirundo tahitica) and Barn Swallow (Hirundo rustica) (above) come together in the evening before dusk to roost on the branches of certain trees. During this period they generate much noise as they squabble over their favourite perch before settling down for the night. Although asleep, these birds are alert and will suddenly move off amidst much noise if disturbed. Early next morning, just before dawn, they wake up, yawn, stretch, refreshed but hungry. Then off they fly to forage.

Hole nesters like woodpeckers usually sleep in tree cavities. Ground nesters sleep on or near the ground.

Obviously nocturnal birds like owls and nightjars sleep during the day.

And many birds “talk” in their sleep and some even sing on moonlit nights.

Input by YC, image above by Cheong Weng Chun, below by YC.

As far as we know, there is only one Great Hornbill (Buceros bicronis) in Singapore. And this bird is an escapee, probably from the Jurong Bird Park some years ago. For some months now, this bird has paired up with a Rhinoceros Hornbill (B. rhinoceros), another escapee. Two earlier reports (1, 2) give accounts of the activities of these two hornbills prospecting for a nesting cavity in an old albizia tree (Paraserianthes falcataria) around the Eng Neo area. They arrived during most mornings of late February and March 2006, spent half an hour to an hour around the area before leaving. Sometimes they also came during the evenings. Towards late April and May these birds appeared less regularly.

We have always wondered where the birds ended up at night. At last we have part of the answer.

Brian Ng alerted me of a Great Hornbill that regularly arrived every evening around 7.00 to 7.15 pm to spend the night on a branch of a rain tree (Samanea saman) outside his fifth level apartment window around Adam Road. The hornbill stayed all night in this tree but come morning, usually around 6.45 to 7.00 am, it started moving, stretching its wings and preening before flying towards Bukit Timah Nature Reserve. Or that was what Brian thought.

But I think it flew to nearby Eng Neo where it met up with the Rhinoceros Hornbill.

The Great was always alone at the roost. And Brian never saw the presence of the Rhinoceros. Now where can the Rhinoceros be roosting at night?

Towards the end of April onwards the bird visited less regularly, coinciding with its irregular visits to the Eng Neo area. Brian has since confirmed (30th May 2006) that “The Great hasn’t returned… in the past weeks…”

Thanks Brian for the alert. Image by Chan Yoke Meng.

Brian’s video can be viewed here.