Good day Friends! Its Bird ID - Part 2!
We are going to look into the next attributes which may help the bird identification, which are shapes and sizes. Most new birders will go for colours to ID a bird. They often left out shapes and sizes of those birds. It is very crucial to record these two matters.
Size can be described as "how big" or "how small" a bird relative to some commonly seen bird species. For an example, you can note it as, "smaller than a Spotted Dove" or "bigger than a House Crow". This way you may able to distinguish birds with similar colors but with different size.
Shapes can be described by the look of their bills, tails, legs or even the birds overall body shape. Overall body shape will give the idea of the birds' general name. That's first thing comes to the mind when we trying to find the ID of the bird. This could be helpful when you unable to see the bird's plumage due to backlight, you may use the shape of its silhouette to gets its general ID.
You may also notice that not all birds have the same stance when they perch. Some do perch in a "hunched" manner, like the cuckoos or doves. Some perch in upright stances, like some raptors. Perching stances also can be a vital information that you may use to ID a bird.
Lets continue with the bill or beak. The shape and the size of the bill of a bird will give an idea to us about its diet and feeding habits.
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| Shapes of Birds' Bill |
Seed eaters like the sparrows, weavers and munias has short and thick bill to extract the seed from the husk. Insect gleaning birds like the tailorbirds and warblers has rather thinner beak. Nectar feeders like the sunbirds and spiderhunters has long, tubular and slightly bent bills in order to probe flowers for nectars. Some spiderhunters use that bill to probe for insects and larvae in tree holes. Raptors have large and hooked beak to shred meat from their preys. So, shape of the bill definitely will aid you to ID a bird correctly. Do consider to note the color of the bill as well.
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| Seed Eater |
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| Nectar Feeder |
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| Meat Eater |
Color of the bill helps you to find the gender of the bird (i.e. ducks), or even the age of the bird. For an example, an adult Black Naped Oriole has a pink bill, while a sub-adult has a black bill, which gradually changes to pink as it grew. Another example, is the White Throated Kingfisher; adult bird has a red bill, whereas the immature bird has rather brownish bill. Check if both upper and lower mandibles are same in color or different.
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| An immature Black Naped Oriole, with black bill. |
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| An immature White Throated Kingfisher, with rather brownish bill |
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| Beak/Bill Anatomy |
The upper mandible is known as premaxillary while the lower mandible is called mandibular. It may have a structure called "nail", which serves different purposes depending on the birds' diet, whether to grasp prey (like in shrikes) or for digging purposes (in fowls). The color of the nail is something important to note as it is used to distinguish male and female birds, as well a bird's age.
I learnt that bill details are very much important to be noted when I was trying to ID waders. For an example, to distinguish Lesser Sand Plover from the Greater Sand Plover, you may need a closer examination of their bills. Greater Sand Plover has a rather heavier bill compared to the Lesser Sand Plover. The culmen bulge for the Greater Sand Plover is at 1/2 length of its bill, compared to its lesser cousin. However I have to remind you that some juvenile Greater Sand Plovers really hard to distinguish from the Lesser Sand Plovers. In this case, you have to find it out by comparing their legs. Greater Sand Plovers have yellowish legs, while the lesser has a black leg. If let say, the legs are covered in mud...I'm so sorry, getting its ID is a tough job then.
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| Lesser and Greater Sand Plover sketch |
Similar to this, I had tough time to ID to similar looking leafbirds, the greater and the lesser green leafbirds. Some field guides do mentioned about the thin yellow margin on the Lesser Green Leafbird' black throat markings. However its not that easy to see the yellow margin unless you have a closer look. So what I did, I look at the bills. Greater Green Leafbird has a slightly bigger bill, with a hooked end, compared to the Lesser Green Leafbird. I have seen Greater Green Leafbirds taking small lizards and bigger insects, therefore the larger and hook-ended bill is much handy for them, in order to grab squirming preys.
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| Greater Green Leafbird |
To be continued...
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