Japanese Skylarks in December

December larks are still mainly in fresh plumage though the tertials are often beginning to wear by then. Below are images of six birds I saw along the Yodo River between Kyoto and Osaka this month (December 2014).

A couple of typical birds with prominent rusty ear coverts and pale surrounds.

Unfortunately I only have this single shot of the interesting lark below. This is the only bird I saw during the month which isn't immediately recognisable as japonica. This because of a combination of some plumage features which aren't typical so lending it a slightly different appearance, and the long primary projection. Because of the variability in Skylark plumage any seeming oddness about this bird is probably meaningless and I'm left with only the primary projection to wonder about.

The primary projection is almost 40% longer than the visible length of the longest tertial whereas that of japonica is usually about equal in length to, or even shorter than, the longest tertial. This seems a very significant difference however an October Hegurajima bird which I believe to be a continental taxon had a primary projection of about 150% of the longest tertial, in fact about equal to the two longest tertials.

A somewhat odd looking lark with a much longer primary projection than I'm used to seeing with japonica.

A japonica with a very short primary projection, most are slightly longer than this.

Four images of a fairly typical japonica.

Another bird, this showing spread wing with very indistinct trailing edge.

Another typical japonica, fairly deep, stout bill and primary projection about equal to the exposed length of the longest tertial. The breast has a very clear pectoral band, warmer than many birds, and washed flanks with rusty-buff streaks.

Underparts very similar to the previous bird but slightly less saturated. The striking thing with this bird is its thin bill, almost pipit-like. This is the only individual I've photographed where the eye is deeper than the bill base. Below are four more shots showing the spread wing which has a narrow but whiter trailing edge than the earlier spread-wing shots.

I have a large number of images of birds from March but very few from January or February which I hope to rectify in early 2015.