-
Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.
Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
Raptor, Danum Valley, Borneo - June (1 Viewer)
- Thread starter mtrevillion
- Start date
I'm not familiar with lesser but understood the bill to be too gracile, the underwing pattern too "patchy" for grey-headed? Those grey-headed fish-eagle I've seen would have a more distinct brown wash to the breast. But happy to be wrong...
Well could be. I think I'm seeing something like this [assuming it's correctly id'd]:
https://macaulaylibrary.org/asset/1...68.516187097.1617631679-1465016617.1534520986
Bird on your link does indeed seem to match the OP's bird. My guess from the f/guides is that that Macaulay pic is misidentified but I've no way of demonstrating that.
This bird
http://orientalbirdimages.org/search.php?Bird_Image_ID=17784&Bird_ID=868 (if correctly identified) suggests that the OP's bird's tail is wrong for lesser fish-eagle - but I can't find any grey-headed in the OBC dbase with a tail to match the OP's bird's (these two spp perch conspicuously so seem mostly to be photographed that way, sadly!).
It's difficult to see how lesser could go through a plumage-progression from pale-mushy-tailed juvenile to dark-mushy-tailed adult while passing through a plumage that has a crisp black terminal tail-band (the OP's bird). But what do I know
I've always found this pair awkward to separate when not showing obvious features.
Well I was curious to see if I could make any more of this so I read the sections in raptors of the world and started to look at wing profiles more closely. Raptors says for grey-headed "wings similar but in proportion wings relatively slightly shorter and tail longer; wing span 2.2x length".Bird on your link does indeed seem to match the OP's bird. My guess from the f/guides is that that Macaulay pic is misidentified but I've no way of demonstrating that.
This bird
http://orientalbirdimages.org/search.php?Bird_Image_ID=17784&Bird_ID=868 (if correctly identified) suggests that the OP's bird's tail is wrong for lesser fish-eagle - but I can't find any grey-headed in the OBC dbase with a tail to match the OP's bird's (these two spp perch conspicuously so seem mostly to be photographed that way, sadly!).
It's difficult to see how lesser could go through a plumage-progression from pale-mushy-tailed juvenile to dark-mushy-tailed adult while passing through a plumage that has a crisp black terminal tail-band (the OP's bird). But what do I know
I've always found this pair awkward to separate when not showing obvious features.
Looking at nos of fingers, I think lesser normally has around 7, grey-headed 8-9. This bird is in moult which makes judging difficult but I think fingers are closer to lesser. Similarly, wing proportions difficult, but again I judge it longer winged.
Lastly, I went back to Macaulay and looked for more images. I found several others by other photographers listed as lesser with similar tails to the op, e.g.
https://macaulaylibrary.org/asset/97477321
https://macaulaylibrary.org/asset/37658781
The second suggests how this pattern appears: it's due to retention of immature's tail banding. If this is faded tail can appear white
I can't see how this could explain the OP's bird. As I said, it would mean having a crisp distinct black terminal band as an intermediate stage between a mushy pale darker-ended tail (juv/imm) and a mushy dark darker-ended tail (adult) - which would be altogether weird. Anyway - beyond me: it needs somebody with bags of field experience and/or a handy skin-collection to sort it out...
'the border between the dark terminal band and the pale base is uneven in Lesser, while it is crisp in Gray-headed'
Ta, Niels. that is (ish) the point I'm making - tho it doesn't explicitly address the issue of our problem birds (the OP's bird and 3 Macaulay birds), viz. crisply-tail-banded birds with weak thin barring on the white basal area.
Ta, Niels. that is (ish) the point I'm making - tho it doesn't explicitly address the issue of our problem birds (the OP's bird and 3 Macaulay birds), viz. crisply-tail-banded birds with weak thin barring on the white basal area.
Andy Adcock
Worst person on Birdforum
Surely, shape alone is enough to call this Grey-headed?
On the other hand take a look at the picture and comments in this ebird checklist: https://ebird.org/checklist/S34832475#_ga=2.255341768.1518534851.1617807476-2028801510.1583343203
Niels
Niels
Indeed that's another bird of this plumage-type (the 2 photos are of the same individual - and, by 'dirty white upper tail parts', I take it that the ebirder means the basal part of the undertail). It has very fat wings, which (I guess) is a further indicator of grey-headed fish-eagle.
I read this the opposite way. Tail fits with lesser (no clear white here), arguably 7 fingers and, although the wings appear "fat", a rough estimate suggests they're more than 2.2x body length (but more accurate measurements welcome...). Tail send relatively short. So lesser for me...
[Edit. More curiosity on my part. I had a look at the first image Niels linked and did some pixel measuring. The ratio of wingspan to body was between 1 : 2.6 & 1 : 2.8. Even allowing for inaccuracies in this approach from angle etc I think this is clearly greater than 1 : 2.2. I think this demonstrates that "broad winged" in this context can be misleading.]
Last edited:
Grahame Walbridge
Well-known member
Immature plumages of LFE And GHFE are not well described but this is surely a 4cy+ Lesser Fish Eagle, structure looks fine IMO. The rectrices are largely dirty, greyish-white and will darken with age, whereas a similarly aged LFE would show a largely pure white tail with the odd dark marking.
Grahame
Grahame
Last edited:
For avoidance of doubt . . . You feel that the sharp proximal edge of the terminal black band is in order for lesser fish-eagle?
After sitting on the fence for a few days, I'm also going to come out in favour of Lesser. In case I get accused of being a Monday morning quarterback or whatever the expression is, I'll try to set out my reasoning. At this stage of development (I also think this is a subadult bird), I would expect to see a contrast between the grey head and deep brown breast - this bird is fairly uniformly grey (it doesn't help that the breast feathers are wet, making the breast look darker than it is, I suspect). The basal part of the tail isn't clean white, with brownish vertical bands, and I think the contrast with the terminal band is exaggerated by the light being directly behind the tail - I suspect that in different light conditions, the contrast would be less noticeable. Lastly, the wings don't look broad enough - I'm seeing 6-7 fingers when Grey-headed regularly seems to have 8.
Similar threads
