Following my curiosity about the plumage of a female-type Watercock which I posted in the earlier post, I decided to investigate some more on the various plumage of this species. The result, however, still left me with even more questions, but I thought it would be interesting to share what I’ve found anyway.
So far, I have not found any literature on ageing and sexing of Watercock on the net. The only place where I could find some information regarding the identification of plumage is the field guide to birds of Thailand and South-East Asia by Craig Robson, of which he states that:
Male non-breeding Like female non-breeding, but possibly shows broader, more defined underpart-bars.
Female breeding Smaller and smaller-billed than male, upperside dark brown with buff feather-fringes and greyer fringing on hindneck, upper mantle and wing-coverts; crown fairly uniform, sides of heaf pale buff with brownish cheeks; underparts generally buffy-white, but deeper buff on lower foreneck/upper breast and undertail coverts, and whiter on throat and center of abdomen, marked overall with narrow wavy greyish-brown bars (denser on lower foreneck, breast, flanks and undertail-coverts); bill, legs and feet greenish. In flight, shows white leading edge to wing like male.
Female non-breeding Underparts somewhat more heavily barred.
Juvenile Like female non-breeding (both sexes) but upperparts more broadly streaked warmer buff, crown narrowly streaked buff, sides of head and underparts rich buff with narrow dark bars (may be almost lacking), white on throat restricted to centre; respective sexes smaller than adults.
So this is the same bird as in the previous post, which I will call it W1. The main characteristics of this bird include brightly coloured bill, rich buffish plumage especially on the head and underparts, very restricted white on the centre of throat, underparts almost unmarked with very few faint narrow bars and very broad buffish fringes on wing and tail.
According to the description by Robson as mentioned above, I think this bird actually fits more to a juvenile rather than an adult female. The only thing that doesn’t fit to the description is the plain darkish brown crown without any streak. However, timing raises some doubts since the bird was found in early-mid rainy season when most male birds are still calling. It’s hard to believe that a juvenile bird of this year has already fledged. The tertials of this bird are also rather worn, so it must have been out there for quite some time and is very unlikely a juvenile, in my opinion.
On July 20, I had a chance to photograph another female-type bird, W2. This bird has obviously duller plumage than W1 with denser and more distinct barring on underparts, lower neck and upper breast. The fringes on mantle and wing coverts are also buffish-grey. The fringes on wing and tail seem to be narrower and duller but hard to be certain as the feathers are relatively worn. The bill is much duller without any red or orange colouration and the crown seems to be slightly mottled, not plain dark brown as in W1. The throat also looks paler but not clearly whitish. In flight, I noticed obvious white leading edge to the wings.
According to these characteristics, I think W2 is an adult female.It is most likely in a breeding plumage according to the timing and white leading edge on wings (even though Robson, however, didn’t mention about the wings of non-breeding female). It also came out from the field to look out for the source of the playback call which I was using.
Now let’s compare to what I found on the internet.
This bird is obviously a female in breeding plumage, but what is puzzling is that the plumage looks unusually plain, especially on the underparts and neck. The body also looks much greyish. The fringes to the upperparts are narrow and greyish as well.
While on the other hand, this bird which is also clearly an adult female in breeding plumage, shows a strikingly rich buffish plumage with very broad fringes to the wing and tail just like in W1. It actually resembles W1 a lot, except that it has duller bill, more white on throat and more strongly barred underparts.
This photo shows 2 non-breeding birds which look slightly different from each other. Judging from the size, I think they are both of the same sex, either male or female I can’t be sure. The one on the right is interesting as it shows a very striking white throat with dark greyish wing mantle and coverts. Another bird, however, has warmer buff fringes and less distinct white on throat.
This one strikes me as a non-breeding male due to its strong built and blackish tail. The barring on the underparts also fits to the description mentioned by Robson as being broader and more defined.
While this one is probably a non-breeding female according to the fainter barring on the underparts and the time when it was photographed which was in early February. It seems to have, however, less densely barred breast and underparts than W2 which should a breeding female. This, again, contradicts to the description by Robson.
The last one looks very similar to W1 but with darker bill tip and culmen. The underparts bars are also more distinct with less rich buff on the head and underparts. The fringes on the upperparts seem to be equally broad. Again, as W1, it seems to fit to the description of juvenile bird by Robson.
In conclusion, I find the plumage of female/juvenile-type Watercock extremely varied. I don’t think I can claim the age, sex and type of plumage of any of the birds shown here with confident, but it was still worth investigating. It really opens me up to more questions and urges me to watch these birds even more carefully. If any of you have more literatures regarding this issue and would like to share, I’d be more than glad to hear.