KC Tsang was at Turf City on the morning of 7th January 2008 “observing a flock of
swiflets and swallows flying back and forth catching
insects in mid air.

“I was tracking one of them with my
camera, and taking pictures of them flying.

“However,
this is one photo that had captured one very unusual behaviour of the bird. It was that the bird was able
to fold itself and reach its rump to scratch it in
flight, and in midair… (I use the word scratch
for lack of a better term) and continued flying
without falling out of the air . Amazing!”

Swifts (Family Apodidae), that include swiftlets and needletails, are among the most aerial of birds. They regularly feed on the wing, sometimes even copulate in midair. What is extraordinary is that they even indulge in aerial roosting, although this has been proven with certainty only for the Common Swift (Apus apus).

If these birds can sleep when flying, it is no small feat to scratch while in the air.

On the other hand swallows (Family Hirundinidae), while highly aerial, often land on branches, utility wires, etc. where they can indulge in preening and scratching in the comfort of the perch.

On 6th January 2008 Lin Yangchen released his study of a juvenile Yellow Bittern’s (Ixobrychus sinensis) first venture out of the safety of pond bank vegetation to explore the new world (below left) and the hunting skills of an adult.

“Before it could get very far on the narrow stem, it freaked out and hurried back in, losing its footing in the process and flapping its wings to regain it. A couple of days later, it had become more confident and made its way to the reeds farther out.

“It stayed still for quite some time, its feet straddling the reeds, not knowing what to do next (above right). Its predicament was quite calamitous, with nothing but water below. I was late for work so I could not stay to find out what happened next. The parent was never seen with it.

“About a week later, when the water level had receded due to dry weather, an adult was seen hunting.

“It is not certain whether this was the juvenile that had grown up, or another bird. It has two modes of prey approach - the slow prowl in the photo on the left (top) and a brisk walk to quickly make up the distance when needed. When there are more underwater obstructions like leaf litter, it lifts its feet higher up when walking, its body leaning more towards the supporting foot (left bottom).

“On 20 Feb 07, there was a post on the blog saying that the bittern needs to move the head left/right and front/back during prey tracking in order for the two eyes on different sides of the head to see the prey. However, my particular bittern did not move its head at all when tracking prey. Maybe it moved its head when walking fast towards the prey area, like most birds bob their heads when they walk, but in the last stages before prey capture, there was no such movement.

“This photo below (left) shows that the monocular camera lens is able to capture both eyes in the same picture, suggesting that the bittern has stereoscopic vision without having to move the head.

.

“It seems from the picture that the long bill does not bisect the stereo vision. Indeed, the long bill might increase the accuracy of the stereoscopic system, as any deviation from the correct firing angle will cause the bill to block one of the eyes from seeing the prey. In other words, the straight-line distance between the two eyes may have evolved to be of a particular fraction of the distance between the eyes and the tip of the bill, so as to optimise the accuracy of the aiming system.

“When the bittern has locked on to the target, the neck extends fully (or to the extent required) in a split second, catapulting the bill towards the target (above right).

“Notice that the nictitating membrane is closed during firing to maintain the watertight integrity of the eye socket. The accuracy of the correction for the refraction of light is indeed amazing, as it has only one chance to catch the fish.

“After catching the fish in the tip of its bill, it flips the fish nearer to the base of the bill in preparation for ingestion. There is a transition moment at which the fish (still alive, with fins flapping) is in midair (right).

“All this happens extremely fast, and before you know it, it has swallowed the fish. It has to happen this fast because the fish would otherwise have a higher chance of wriggling free.

“This bird is a skilled fisherman.”

On 23rd November 2007, Daniel Koh spotted a Grey Nightjar (Caprimulgus indicus), a rare passage migrant and winter visitor. The bird was perching on a large branch (left). Many birders came across the Grey on a branch, unlike the resident Large-tailed (Caprimulgus macrurus) that is usually seen on the ground. Being a perceptive birder-photographer, he noticed that the bird was sitting along the branch and not at right angle to it as with most birds. So he was curious to have a look at its feet.

As luck would have it, it was Chan Yoke Meng who managed to get a shot of the bird’s foot when it was scratching its head (below).

A nightjar’s feet are weak, as seen in the above image, as they are adapted for resting on the ground. The toes do not have the powerful grip of most other birds and presumably the bird has difficulty perching on slender branches. It is thus able to only perch on a large branch, and only sits along it.

However, this does not mean that the bird is clumsy on the ground. Many species can walk quite strongly, especially the chicks. And many occasionally feed on the ground. The toes are partly webbed and the middle toe is pectinate, as seen in herons. This is possibly used to remove parasites and straightening out the rictal bristles during preening.

Nightjars are nocturnal birds, roosting during the daylight hours. And it is during such hours that they are most vulnerable to predators. This is where their cryptic plumage comes into play, to avoid detection during the day when they are roosting.

The head appears large in relation to the body. The bill is small and appears weak. The gape is enormous and lined with long, extremely tactile, rictal bristles. These bristles are modified contour feathers whose barbs are absent. Such are the adaptations for aerial feeding.

The eyes are large and laterally placed. At night they respond to light by shining, an adaptation to improve the vision during dusk and dawn as well as during the night when the moon is absent from the sky.

Many have conspicuous white patches in the primary as well as outer-tail feathers, as seen in the Grey above, when it was stretching its wings. When the bird is resting, these white patches are never seen, becoming obvious only when in flight. These markings come into play during territorial aggression, courtship and defence displays as well as to distract predators at the nest site.

When approached, the bird may flatten itself to reduce shadow and outline, as well as close the eyes (see top image). Such behaviour provides total camouflage and it is literally unseen, especially on the ground, until you are very near, when the bird suddenly takes off with a noisy flutter.

The bird is an extremely strong flier, being provided with long, slender wings.

Top image by Daniel, others by Chan Yoke Meng.

In July 2007, after two years of blogging, BESGroup’s blog logged 100,000 visitors. Now, exactly six months later, we have reached another milestone - 200,000 visitors.

A recent web-rating by an independent professional editor for weblog “blogged” rated this blog as ‘Very Good” and awarded it 8.3 out of 10.0 points. The editor used four criteria: 1. frequency of updates; 2. relevance of content; 3. site design; 4. writing style.

We have linked up with many overseas bird blogs. Many others have discovered us as shown below:

Based in the US, Birdfreak: The Bird Conservation Blog has been recommending us to birders all over the world (left). So have the Malaysia Bird Forum and thaibirding.com.

GlobalVoices, founded at Harvard Law School’s Berkman Center for Internet and Society, has also made reference to us. This is a research think-tank focused on the internet’s impact on society.

One of our posts was referenced in an article on the Common Myna that appeared in Wikipedia, the free encyclopedia,

And a Chinese blog based in Biijing literally re-posted chunks of our recent postings, images and all.

OrganicBurials.com makes special mention to our recent post on the Chestnut-bellied Malkoha.

On the local scene, Youth.SG, an online portal for the youth of Singapore, has linked up with BESG. So has Singapore Environmental Blogs.

The above are the new local links. Apologies for not mentioning the many other local links, so as not to make this post excessively long.

Once again BESG thanks one and all for support - photographers for sharing your bird behaviour images as well as permission to post your images, birders for sending your sightings and observations.

With your continued support, we await the coming of the half million hits.

Hornbills are mainly fruit eaters, although their diet also includes invertebrates including caterpillars, small amphibians, reptiles and mammals.

In Thailand a total of 13 species have been recorded. The different types of foods these spectacular birds take have been well documented by the Hornbill Research Foundation of Thailand.

Figs (Ficus spp.) are an important source of the hornbill’s diet. There are many species of figs and many of them flower throughout the year. This means that there would always be some trees figging at any time of the year.

Other than figs, a total of more than 60 species of rainforest trees provide these birds with food. These are mainly under-storey trees, many of which are also found outside the forests.

The most important of these plant families include Myristicaceae: Myristica (left top), Knema (left middle) and Gymnacranthera (below, top left); Meliaceae: Aglaia spectabilis (below, top middle), Chisocheton (left bottom), Dysoxylon; Annonaceae: Polyalthia (below, top right); Lauraceae: Litsea (below, bottom left); Myrtaceae: Syzygium; Palmae: Oncosperma; Rubiaceae: Canthium below, bottom right); Sterculiaceae: Sterculia (below, bottom middle) and Theaceae: Ternstroemia.

Besides fruits, hornbills have been known to take millipede (below left), caterpillar, grasshopper, beetle (below middle), gecko and rat (below right). An animals diet is most important during nesting as the growing chicks need a constant source of proteins.

Two earlier posts on hornbills of Thailand are found HERE: 1 and 2.

Input from Hornbill Research Foundation; images courtesy of Dr Pilai Poonswad.