Autumn is approaching and some early migrants have already arrived in my local patch. Snipes are among the first waders that usually turn up. I think it’s a good time to review the identification of the 3 extremely similar species that can be found in Thailand.
The three species that will be discussed in this post are 1) Pin-tailed Snipe, 2) Swinhoe’s Snipe, and 3) Common Snipe. All three species are non-breeding migrants in Thailand with Pin-tailed and Common Snipe being common and widespread throughout the country, while Swinhoe’s Snipe is extremely rare and possibly largely overlooked. Field identification of Common Snipe from ‘Swintail’ (Swinhoe’s/Pin-tailed) Snipe is quite straightforward, but to identify Swinhoe’s from Pin-tailed Snipe requires much more effort and good photographic evidence.
Let’s start with the odd one among the three, the Common Snipe (Gallinago gallinago). As the name suggests, it is a common winter migrant throughout Thailand. It can be found in almost every type of wetlands from rice fields, shallow lakes and even coastal mangrove forests. In northern Thailand, it’s the most abundant species during mid-winter, while numbers of Pin-tailed and Swinhoe’s usually peak during passage migration.
Structurally, the Common Snipe usually appears rather slim and long-bodied as the tail is noticeably longer and extends much further beyond the primary projections than in Swintail Snipe. On average, it also has longer bill than in Pin-tailed Snipe but quite similar to Swinhoe’s Snipe, though bill length of all 3 species can vary between individuals depending largely on age (juveniles often have shorter bill). The crown also usually appears flatter than in Pin-tailed Snipe with crown peak located towards the rear behind the eye.
It is probably easiest to identify the Common Snipe while in flight. The underwings of Common Snipe are much different from both Pin-tailed and Swinhoe’s Snipe by having more extensive amount of white on the barring of underwing coverts. The upperwings are also different by having a bold white trailing edge along the secondaries which can be seen clearly particularly when landing. Both Pin-tailed and Swinhoe’s Snipe lack such bold white trailing edge. However, the amount of white on the underwing coverts can be quite variable ranging from completely white to very little white with extensive dark barring just like in Pin-tailed and Swinhoe’s Snipe, but the white trailing edge along the secondaries seems to be consistent among all birds that I’ve photographed.
Another diagnostic feature of the Common Snipe is the tail feathers. Unlike in Swintail Snipe, the tail feathers of Common Snipe are all equally broad. Its Thai name นกปากซ่อมหางพัด literally means “fan-tailed snipe” because of this characteristic. However, to see the spread tail usually requires a lot of effort as it is only shown when the bird is stretching, preening, landing or when performing the alert/defensive posture.
Next is the Pin-tailed Snipe (Gallinago stenura) which is another common winter migrant in Thailand. It can be found throughout the country but the majority only pass through northern Thailand in autumn and spring and spend mid-winter around central and southern Thailand. Compared to Common Snipe, it has a much shorter tail on average. The tail only slightly extends beyond the primary projections. In some birds, the tail doesn’t even extend beyond the primary projections but are about the same length. On average, the bill is also shorter than in Common and Swinhoe’s Snipe, though the length can also vary. The head usually appears rather rounded with crown peak positioned in front of the eye unlike in Common Snipe.
In Thailand, the Pin-tailed Snipe is usually the first one to arrive in autumn. It can be found in various habitat types including rice fields, marshes and even streams or bogs in forested areas but rarely found in coastal habitats unlike the Common Snipe.
In flight, Pin-tailed Snipe can be told from the Common Snipe by having heavily and evenly barred underwing coverts with no bold white trailing edge along the secondaries. However, both Pin-tailed and Swinhoe’s Snipe share the same wing pattern, so they can’t be judged by this characteristic.
As the name suggests, the most diagnostic feature of the Pin-tailed Snipe is the tail, more specifically the outer tail feathers which are extremely narrow and pin-like. The best way to identify Pin-tailed and Swinhoe’s Snipe is by judging the width of these outer tail feathers. This can be done quite easily when examining the birds in hand, but in the field, you would need to see them up close while they’re either preening or sunbathing or obtain good photos of the spread tail while landing. I usually spend several hours observing them in the field only to get glimpses of the outer tail feathers. I find early morning to be the best time to observe them, particularly a sunny morning after a rainy night, as the birds would be rather wet and spend a lot of time sunning and preening themselves which offers a higher chance of seeing the outer tail feathers.
Lastly, the Swinhoe’s Snipe (Gallinago megala) is the rarest among the three species in Thailand. It is known from just few records from northern and central Thailand, but I’m certain that it is much overlooked because of the difficulty in the field identification. It seems to be recorded in Malaysia and Singapore quite regularly which suggests that it passes through Thailand. All Swinhoe’s Snipes that I found in Chiang Mai were recorded during the autumn migration (September-October).
Structurally, I find Swinhoe’s Snipe to be very similar to Pin-tailed Snipe but looks slightly larger and bulkier in the field. The crown can often appear rather flat like in Common Snipe but can also appear rounded like in Pin-tailed Snipe depending on the posture. On average, the bill is slightly longer than in Pin-tailed but slightly shorter than in Common Snipe, though, again, the bill length can be quite variable. On average, the tail is slightly longer than in Pin-tailed Snipe and I have yet to see any photo of a Swinhoe’s Snipe that shows a tail that doesn’t extend beyond the primary projections.
As mentioned earlier, the most definitive way to identify Swintail Snipes is by judging the outer tail feathers. In Swinhoe’s Snipe, the outer tail feathers are narrower than the central pairs but not as narrow and pin-like as in Pin-tailed Snipe. The number of such narrow outer tail feathers are also fewer than in Pin-tailed Snipe. Again, this characteristic can only be seen when the tail is fully spread, particularly when the bird is sunbathing, preening or landing. Good photographic evidence which shows the spread tail is strongly needed to confirm the identification of Swinhoe’s Snipe in Thailand. I was lucky to observe and photographed at least 2 Swinhoe’s Snipes from my local patch in Mae Faek, San Sai, Chiang Mai. I’m quite certain that there were more which I overlooked or couldn’t conclude the identification as the outer tail feathers couldn’t be seen. It has been an annual challenge for me to look out for Swinhoe’s Snipes in autumn for the past few years. As the bulk of snipes are expected to arrive in my local patch within the next few weeks, it’s about time to brush up my sniping techniques. Hopefully, I will get to find more Swinhoe’s Snipe this season.