Juvenile Pallid Harrier identification

The Fulmar- oiled bird at Hillwell, Shetland

I saw this bird several times over a 2 week period. It was a little surprising that questions about the bird’s identity were not more forthcoming. Certainly I had some questions, as the classic Pallid Harrier ‘pale collar’ was not normally visible. Thankfully I was able to quiz Roger Riddington, the bird’s finder, who knows the subject better than me, having a UK self-find list of 4 for the species! On the issue of the pale collar, in fact, earlier photos do show a collar, but in some way the effects of the oiling obscured its presence. On some close perched views I could just make out the ‘ghost’ of what seemed to be a pale collar. This photo by Ian Cowgill was taken the day before we saw it with another interesting bird from Fetlar at end:

Juvenile female Pallid Harrier at Hillwell. The iris looks dark, therefore female.

Here a selection of Roger R’s photos with his helpful comments on the bird:

Photo a

Photo b

Photo c

Photo d

Oiled Pallid Harrier (by R.R.)

ID as Pallid based on three basic areas (it’s clearly a slim-winged harrier, with four fingered primaries, inc. P10, not five as in Hen/Northern, and P6 much shorter than P7).

1)     Head pattern. The pale collar is unusually indistinct (for a juv Pallid – the bird is undoubtedly a juv), which seems to be a function of the Fulmar oil. However, as Ian Cowgill’s pic (top) shows, also mine (photos a-c, taken early Sept) the collar appears to be of even width and stretches almost from the pale patch on the crown down to the throat. Monty’s which resemble this normally show a less extensive ‘moon-shaped’ collar, which tapers top and bottom, which is less extensive and doesn’t reach onto the throat. Also, as all these pics show, this Hillwell bird has a lot of dark feathering on the cheeks (by which I mean below the eye, not the ear-coverts – behind the eye), which suggests Pallid rather than Monty’s. Finally, there is extensive dark behind the pale collar (the ‘boa’), which is typical of Pallid.

2)     Underwing. The contrast between the almost solidly dark secondaries and pale primaries is strong and consistent. Also, although it’s harder to judge, the tips of the inner primaries seem to be at best grey (OK for Pallid), and in some shots look pretty pale, thus lacking the more typical dark rim to all the primaries that Monty’s shows (eg awful pics photos e-f). Also photos g-h suggest that not all the ‘finger’ of the longest primaries is dark, which you might expect in Montys (hard to be certain of that cos of the state of the feathers).

3)     Overall jizz. To me, when I’m watching this bird through bins, it looks a fairly hefty harrier, with a relatively broad-based arm and not incredibly pointed hand. It doesn’t give the impression of being a slim, kite-like Monty’s and it has allegedly been misidentified as a Marsh Harrier once or twice on account of the dark head and neck and extensive pale crown. So I think the jizz is better for Pallid than Monty’s.

Photo e

Photo f

Photo g

Photo h

Finally…and by way of comparison: Brydon T and Pierre A Crochet popped off to Fetlar (cheeky) while I was changing groups on 30th Sept. They found this juvenile Pallid Harrier, with noticeably weak dark boa. All good learning:

Juvenile Pallid Harrier, Fetlar, 30th Septmber 2011, Brydon Thomason.

11 thoughts on “Juvenile Pallid Harrier identification

  1. Mark Chapman

    Hi Martin -Oiled bird does seem to be the most ‘Montagu’s’ -like bird of the influx here, as RR suggests prob because of the oil; in the more distant pics pattern of under-prims looks if anything closer to Monty’s, but better pics appear to dispel this, and flight feathers seem possibly ‘narrowed’ by oil, and thus harder to see properly.. But also it has an amazingly long tarsus, espec.on perched pics, also visible on many flight shots. This is a pro-Pallid feature, as illustrated in BW 10, 267-269.
    Would be interesting for reference in general to see good pics of a known Monty’s/Pallid hybrid juv, which has happened at least once…
    Another bird with virtually no boa was at Sandgarth/Sandwater Aug 31st (pics on Nature in Shetland website http://www.nature-shetland.co.uk/naturelatest/archives/birdarchive11aug.htm ) – Dick Forsman kindly commented this was within Pallid range of variation..

    cheers
    Mark

    Reply
  2. Jan Jörgensen (JanJ)

    Hi all.

    Interesting bird – the Fulmar-oiled Hillwell harrier!
    Apart from the features mentioned and given the quality of the pic I find it rather difficult to identify it for certain – both as a Pallid or a Montagu´s, since the various pic provide different impressions of structure. One important reason for this is the obvious notched p7, which would be very odd for both Palid and Montagu´s. It is however, the rule for Hen. Further on it shares the wing-formula – shorter p10 which is approx. as long as p5, with Hen, usually approx as long as p6 in Montagu´s. It might be reasonable to consider a hybrid Pallid x Hen.

    Some intresting potential hybrids from this autumn.

    http://tinyurl.com/5tzpcxz
    http://tinyurl.com/3vmy49d
    http://tinyurl.com/6jnekpc

    JanJ

    Reply
  3. Harry Hussey

    The spectre of hybrid harriers, perhaps equally involving Hen x Pallid as Montagu’s x Pallid, has been raised in some quarters, and, while I am not suggesting that the subject birds here are impure, say, it is surely something to be borne in mind, by observers and rarities committees alike, when confronted by a less than classic individual Pallid candidate…

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  4. Pingback: Identification update: Pallid Harrier | Birding Frontiers

  5. John Holloway

    Somewhat surprised that no-one has mentioned the size of the bill regarding these birds when it seems to be well-known (perhaps only abroad?) that Pallid has a noticeably heavier bill than Montagu’s. The photos of the Fetlar bird of Sept 2011 show a big heavy bill – spot-on for Pallid – and our own bird of late October (prob adult female) also has a very heavy bill compared to Hen and Montagu’s. It is difficult to judge this on the oiled bird because of the ‘smoothing’ (flattening) of the head feathers. John Holloway Stronsay Orkney

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  6. John Holloway

    PS I should have added that the Stronsay bird was found feeding on carrion (a dead rabbit killed by a car earlier in the day – so not caught by the bird). I have yet to see a Hen Harrier eating carrion – several thousand sightings and plenty of road-kills here. Maybe this is a valid point re the id – i.e. not Hen if it is eating carrion? I note that on one web-site there is a photo of a female Pallid at a ‘carcass’. Easy to find I suspect.

    Reply
  7. Lars Svensson

    Dear Martin,

    Just saw these photographs. In my opinion the oiled bird is a Montagu’s and the Fetlar bird could be a hybrid. I would not label any of them safe Pallid.

    Reply
    1. Mike Pennington

      Hi Lars,

      Montagu’s Harirer would be a very rare bird in Shetland, rarer than Pallid. Your opinion on why it is Montagu’s would be valued. The Fetlar bird is very similar to a bird that was on Mainland earlier in the influx (at least it can’t be separated from it on available photos). Photos of the initial bird were sent to Dick Forsman because of the indistict boa and he considered the bird to be within the variation of Pallid. Certainly these birds are much more Pallid-like than the putative hybrid that was here a few winters back, which was Hen Harrier like.

      Reply
  8. Lars Svensson

    Hi Mike,
    I think overall jizz is better for Montagu’s, with more slender shape (not just due to being an oiled bird), a quite long tail in relation to arm width and long and pointed outerwing. Also, the amount of white on sides of head is close to what is typical for young Montagu’s but quite extreme for a Pallid. It is difficult to see much of a black dividing line through eye (if there is one it is almost broken and narrow, and on the best photograph lacking), another character in favour of Montagu’s. Why would the normally broad and unmarked rufous-buff collar of a Pallid be so subdues and patchy as on this bird. Oiled, for sure, but why affecting the collar but not the cheek patches which are pale and unpatterned? The ‘boa’ is on the other hand not as dark as one could have expected; here the oil staining must have made the ‘boa’ patchy and ill-defined – rather surprising in my opinion. I also find the darkness of ‘fingers’ in favour of Montagu’s (although admittedly this can be at least partly due to the staining of the plumage). Barring of primaries does not rule out MH, that much it varies. It is a difficult bird for sure, but the main feeling I get is of a Montagu’s Harrier. I would hesitate much to simply say it is a Pallid. I have not seen any discussion why it is a Pallid so cannot judge the argument against my conclusion.

    I am no real expert on these birds, and if others can prove convincingly that I am wrong I will have no problems with that.

    All the best,

    Lars

    Reply

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