Tuesday 28 August 2018

Ageing Spotted Crakes

Since finding the Spotted Crake on the Otter last week, I have been keen to try and age the bird. As with most attempts at ageing birds, you tend to need close views or good photos and the Crake hasn't exactly been close. However, I have managed to get some pretty reasonable video footage using my iPhone and Swarovski Scope at 50X and got lucky with a closer view. This has enabled me to put together a few stills from the video to age it as a juvenile. No great surprise I guess, but I thought I'd put the stills to use as it was interesting to learn about ageing the species. Spotted Crake ageing  seems quite subtle and not always straight forward. A great piece on ageing Spotted Crakes HERE

Despite an adult looking bill - Yellow with red base. The bill is apparently not a good feature to use when ageing.
 It is the pale throat that seems to be one of the diagnostic features in ageing the bird as a juvenile

Pale throat, but not as obvious as some birds. Clear red base to bill shown here though not helpful in ageing.

Again a pale throat is apparently a diagnostic juvenile feature

Dark lores quite obvious even at distance. Could mislead id towards the much rare Sora Rail with poor distant views.
The heavily speckled supercilium is also a good feature of a juvenile bird. Dark lores seem more likely in adult?

Dark loral mask quite prominent again here (more adult feature?) and heavily spotted supercilium more juvenile feature

Dark loral mask also present on the right hand side of bird

No obvious signs of wear in the wing as you would expect an adult to show. 
Feathers appear fresh and rounded as expected by a juvenile.
Distinctive pattern of underwing for a juvenile?
See http://blascozumeta.com/wp-content/uploads/aragon-birds/non-passeriformes/148.spottedcrake-pporzana.pdf

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