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Message: <blockquote data-quote="Tib78" data-source="post: 2667442" data-attributes="member: 71118">Hi Brian,Thanks for the comment and of course, you're quite right: it's more of an educated guess rather than a solid bullet-proof ID.I have had a deep interest for ageing/sexing of Hen harrier in autumn/winter for severals years now. This winter, I spent a lot of time watching/photographying the Hen harriers wintering on an uncultivated land near my house. This small patch has proven to have a tremendous potential : at least 10 differents Hen Harriers photographed, Short and Long-eared owls, Red kite, Peregrine, Kestrels, Buzzards (a Rough-legged was observed last year), up to 18 Great white egrets <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" />eek!: :eek!<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" />etc...I attached a few shots taken this winter (january/february) and here are a few comments of mine regarding their ID (based on literature and my own experience-comments most welcome guys!):-First image: typical adult female, with extensive underparts marking extending onto the undertail coverts. Such wide, drop-shaped marks on the undertail are, in my experience, almost diagnostic of adult female (though rarely, some juv males show a very comparable pattern). Underwing diagnostic: the trailing edge of the secondaries is very thick, almost three times as wide as the trailing edge of the inner hand. The distal pale bar of the secondaries (next to the trailing edge) is also very thick and same goes for the middle black bar. The barring of the primaries is thick and regular. The fingers are in good condition with blunt tips. Additionaly the lesser underwing coverts are rather well streaked which, together with the underbody, gives a relatively uniform appearence to the bird (more on this to come with the images of juvs). This is not visible on this image but the tail is in perfect condition. Note also the yellow iris of this bird and the massive body.-Second image: juv Female (sexing based on iris colour; note the iris looks rather pale in this photo but that because of the light hitting the iris. Under neutral light, it was dark brown). The ageing of birds showing such an underwing is straightforward: the secondaries are completely blackish, save for 2 very faint pale bars. Underbody with the streaking largely confined to the upper breast ("hooded effect") and the flanks lack the broad brown blotching of adult female. Likewise, the undertail coverts are faintly marked along the shaft only. Although it's not obvious on this pic, the tail is rather worn: nevertheless, you can see that the tail as a whole looks quite thin with a frayed tip. Otherwise the plumage is relatively fresh (possibly indicating a bird from Nothern origin and thus latter hatched?) and the primary barring similar to ad female.-Third pic: juv male (sexing primarily based on yellow iris). A bird that displays an underwing pattern rather similar to adult female but note:-the trailing edge maintain (more or less) the same width from the inner hand to the inner secondaries-the trailing is brownish (vs black in ad female)-the primary barring is thin, weak and irregular (indicative of juv male according to Forsman)-the middle black bar of the secondaries is very thin-the tail is heavily ragged-the fingers are worn showing somewhat 'sharp' tips-Fourth pic: juv female (iris colour again), note:-virtually unmarked underbody and undertail-the upper rows of lesser underwings coverts appear plain-heavily worn tail and remiges (especially the fingers)-brownish trailing edge that doesn't widen towards the body-weak primary barringBecause of the rather plain pale lesser coverts and underbody, the dark axilliaries and greater coverts are isolated (compare with the more uniform appearance of ad female)-Fifth pic: juv female showing very well-preserved plumage (Northern bird?) and rather intermediate secondary pattern, picture taken in mid-january. Note:-even width of the trailing edge-the palebars and the black bars of the secondaries are thinner and therefore more numerous than on ad female-largely unmarked underbody and lesser coverts leaving isolated axilliaries and 'hooded effect'Primary barring compatible with ad female and fingers in perfect conditionStructurally, ad females ad juveniles and subtly different. It's hard to transcribe in words, but ad females appear bulkier and broader winged.Based on all this and the combination of the features visible on the picture, I'd say Cristian's bird is an adult female.</blockquote>

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