Oriental White-eye: Feeding the chicks

posted in: Feeding chicks | 6

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Most birds feed their chicks with animal food during the few days after hatching, even those birds that feed mainly on fruits and grains. The Oriental White-eye (Zosterops palpebrosus) is no exception. This bird feeds on insects, fruits and nectar from flowers. The young have been observed to be fed mainly on caterpillars. The images above show the chick at various ages being fed with succulent caterpillars. Other invertebrates like spiders and ants are also popular (below). However, no plant food was seen delivered to the chicks. This is understandable, as growing chicks need proteins more than sugars and carbohydrates.

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The parent birds are kept busy all day long, flying off to forage and returning to feed the chicks. But when they return, they do not fly directly to the nest. They perch nearby and survey the surroundings (left). Only when all is clear do they fly to the nest. Once the bird lands by the nest, the vibrations will cause the chicks to open their mouths fully, even just after hatching when they are blind. And without fail, every chick in the nest will strain its neck upwards with mouth wide open, ready to be fed.

Unlike raptors and such where the parent tears off pieces and feed the chicks one by one, here, every trip brings only food for one chick. Therefore the oldest and naturally the most aggressive of the chicks usually ends up with the most food. In the recent nesting of the white-eye at Kent Ridge, the original three chicks ended up two. The missing chick, obviously the youngest and weakest, was probably dumped out of the nest by its two siblings or else fell off. This was the case in an earlier documentation where the third chick was found on the ground below the nest.

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What becomes apparent once the chick gapes is the reddish colouration of the inner area of the mouth, lined with prominent swollen yellow oral flanges, believed to be “food targets” for the parents (right, arrows).

Immediately after feeding a chick, the adult moves to the rear of the fed chick to await the faecal sac. With its beak, it carefully picks the sac as it appears from the cloaca to disposes it some distance away.

YC Wee & Melinda Chan
Singapore
May 2007
(Images by Chan Yoke Meng)

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6 Responses

  1. […] oral flanges are prominent in the chicks of the Oriental White-eye (1, 2) (Zosterops palpebrosus) (left), which together with the reddish gape make a prominent food target. […]

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  2. […] oral flanges are prominent in the chicks of the Oriental White-eye (Zosterops palpebrosus) (1, 2), which together with the reddish gape, make a prominent food target. We now know that the sparrow […]

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  3. […] that these flanges surround, they serve as “food targets” for the adults to direct food into LINK. As the chick grows older, these oral flanges disappear. Related posts:Another Javan Myna chick […]

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  4. Pramod Thapa

    Just foud an orphaned oriental white eye in the orchard ground. Just found in the nick of time when a snake was about to make a snack out of it. Maybe it fell off during the storm. But the problem now is that i have no idea how to take care of it. It already has its eye open and the distinct yellow feathers can be seen. Can some one help me out. I fed today about six earthworms in the span of about three hours and i stopped feeding it thinking not to over feed it. Please can someone guide me in taking care of this orphaned bird

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  5. Lee Chiu San

    Our Webmaster has requested that I attempt to answer Pramod Thapa’s question on what to try to feed an Oriental White Eye (Zosterops palpebrosa) chick even though I have no first-hand experience with this species. The reason is simple, White Eyes are such minute birds that very few aviculturalists ever attempt to handle the chicks. They are so small and delicate that any rough handling could injure them fatally. We usually only hand-feed chicks of species of birds large enough to be manipulated easily. By that I mean with panicky wild baby birds who are not able to eat on their own, it is easier if they are large enough that one person can hold the beak open while another squirts food down the throat.
    But back to the topic of Zosterops. We know that the adults are general feeders who have a large proportion of nectar and insects in their diet. We also know that birds of most species greatly increase the proportion of insect food in the diets that they provide to their young.
    What can be suitable and readily available substitutes?
    Like I said, never having raised Zosterops chicks, and not knowing anyone who has ever done so, all I can provide is an educated guess.
    First thing you need is a very small syringe for squirting the food into the bird’s beak.
    Now, what should the food be?
    If there is a well-stocked aviary supply shop nearby, I would suggest starting with some lorikeet nectar mixture as the foundation of the diet. Zosterops do drink lots of nectar, and it is nutritious.
    And while you are at the shop, get some powdered or pellet food for insectivorous birds.
    If there is no such shop in your neighbourhood, you will have to make your own nectar mixture. And find some granular substitute for the powdered or pelleted insect eating bird food.
    The basis of my home-made formulations has always been invalid’s food and baby food. Any of the medically approved liquid foods for invalids (such as Complan) will do. Add to this some sweet, fruit-based liquid baby food, the kind you buy at the supermarket.
    Now, where are you going to get the animal protein from, if you don’t want to spend the day catching caterpillars and squeezing out their intestines? At a pinch, hard-boiled egg yolk should do.
    Now comes the difficult part. How do you mix batches small enough for Zosterops?
    All formulations for feeding baby birds do not keep well at room temperature. What I usually do is mix a batch that will fill a beer mug and refrigerate it, only defrosting what I need at each feeding.
    With baby lorikeets, mynahs or even birds as small as bulbuls and starlings, the contents of a beer mug will last about a week. For birds even smaller, such as Zosterops, that same quantity might last well into old age for either you or the bird. But it is really difficult to mix smaller quantities.
    What I suggest you do is blend invalid food, baby food and hard-boiled egg yolk in this proportion 40/40/20.
    The mixture should be runny enough to pass through a syringe easily. Then crush the insectivorous bird food pellets into a powder and add just enough of that powder to thicken the mixture until it will just flow through the syringe.
    Make sure everything is at room temperature. It is very easy to either scald or chill baby birds by giving them food either out of the refrigerator, or that which has been thawed with hot water.
    Fill the syringe, go to the baby bird, and hope that it is realises that you are coming with food. If it gapes, gently insert the syringe and squirt some food into the beak.
    If it does not gape, which very often happens with wild birds that are very afraid of humans, then you need someone to hold it, and gently open the beak, while you squirt food in.
    Birds the size of Zosterops are very small, have very little reserves of energy, and must be fed at very frequently.
    I feed most of my other types of baby birds about six times per day. This should be about the minimum you will need for Zosterops.
    They are unlikely to survive if you feed them less frequently, because, like I said, they have very few reserves and die of starvation easily.
    It’s going to be a lot of work, but luckily, not for long. Small birds are usually not dependent on their parents for more than a few weeks. If it survives, the baby should be able to feed itself within a month.
    I hope that you succeed in raising it.

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  6. Thank you, Lee Chiu San, for the reply. Hope Pramod Thapa is successful in keeping his rescued birdling alive.

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