Orange Juvenile Harrier

But Which One?

Here’s the story. It’s about a juvenile harrier that did a once fly-past at Spurn, East Yorkshire on 28th August 2010.

Mystery Photograph: Identify the species. Answer next month! (any one else remember regularly reading those enticing words?). Flying over shorebirds on the Humber and Spurn’s ‘Narrow Neck’ in the background.

OK . Here it is through binoculars! What species is it?

A juvenile Harrier sp. passes through Spurn’s triangle zone and out across the Humber. Watched for not more than handful of minutes by about 30 observers and never close. What would you have called it?

It was a Montagu’s Harrier, maybe a Pallid Harrier, a Hen Harrier and an (American) Marsh Hawk depending on how well you saw it!

Here’s the story:

The following photo was taken by my daughter Abigail, as we were walking back towards the Bluebell. Leaden skies appeared to the south. Before long large rain drops necessitated a quick dash to the cafe. Pete Wragg joined my family around the table and just as we settled in for welcome victuals, our radios crackled. The same rain that caused us to seek shelter had ‘forced down’ a large raptor. A sleek handed, orangy looking bird-of-prey had flashed past the caravan of one sharp-eyed birder- possibly Montagu’s!

Pete and I grabbed bins and ran out to suitable vantage point. Scanning the fields near the Warren the bird rose up having alighted briefly. “There it is!” Except to me it looked too broad-winged for a super slim Monty’s (eek… perhaps Pallid), which I hesitantly mentioned to Pete. Some 30 birders emerged from sheltered locations as the bird disappeared from our view. Pete and I headed towards the road seeking another vantage. I had no more views. Others watched as it flew alongside the canal zone and very soon, out towards Lincolnshire. Ian Smith managed a handful of distant shots.

So what was it?


Leaden skies, Spurn 28th August 2010, Abigail Garner. Rain forces birds that are otherwise over flying to make landfall and seek shelter.

Pete Wragg woz ‘ere. His untouched tea and bakewell. Even his coat was left behind in our adrenaline filled dash.

Post-sighting analysis: The bird’s identity was briefly discussed. Some were thinking it looked OK for a Montagu’s Harrier. A couple of us felt it too-broad winged, which is why I even contemplated the bulkier Pallid. The answer lay in Ian Smith’s photos.


5 fingers, 4 long ones  – it’s a Hen Harrier. Game over – or its it?

Hmm. What if there had been no photos? What species would have gone down in birders notebooks/ on the internet/ in the evening log at Spurn? The photos above and below show the wing formula of a Hen Harrier. This was not noted as it passed rapidly by. Indeed, flying into strong winds caused the wing tips to be sometimes sleeked back and appear narrow. It was rather plain and orangey looking according to some observers. In these photos it also looks dark-hooded. And the outer primaries appear to have lots of bars- don’t they? As I looked through Ian’s photos on his computer screen – this question came to mind. “Why is it not a Marsh Hawk?”. The North American Hen Harrier. Some features on these slightly blurry photos look good for a ‘hudsonius’.

Juvenile Hen Harrier, Spurn August 28th 2010. See ‘5 fingers, 4 long’ again (4 fingers, 3 long on Montagu’s and Pallid Harriers). Ian Smith (all Harrier photos above also by Ian Smith)

Fortunately Ian photographed a juvenile Hen Harrier exactly one week earlier at the same place- indeed flushed from the same field as the 28th August bird. This one can be more easily identified as a juvenile (Eurasian) Hen Harrier. Actually I would argue, the way some large birds move up and down Spurn – it could even be the same bird!

juvenile Hen Harrier, Clubley’s Field, Spurn 21st August 2010, Ian Smith.

Certainly pretty dark looking ‘plain chocolate’ above – sometimes a quoted feature of ‘Marsh Hawk’. Wing tip appearance of harriers can vary in the field, in photos and even on the same individual (see above).

juvenile Hen Harrier, Clubley’s Field, Spurn 21st August 2010, Ian Smith. Juveniles with a orangey underparts are not unusual. Some juvenile Marsh Hawks can come quite close in general appearance to this. On the finer details, this bird show 3 bars on the outermost long primary and 5 bars each on those 2 long primaries next to it. You would want one more bar each of those (4 and 6 respectively) to claim a Marsh Hawk.

juvenile Hen Harrier, Clubley’s Field, Spurn 21st August 2010, Ian Smith. Count the bars again if you like. Also note the 3 dark bars (including the dark trailing edge) in the middle part of the underwing. Ideally a Marsh Hawk would have a narrower central bar. The trailing edge of the inner primaries is obvious dark and the dark shaft streaks on the undertail coverts caught my eye. Do Marsh Hawks ever show these?

juvenile Marsh Hawk, Connecticut, December, Julian Hough.

Here’s a real Marsh Hawk. Maybe a juv. male (the iris looks like it might be pale). Count the bars. Just about visible – 4 on the outermost long primary and 6 on the next 2 (look carefully). It also has a slightly more solid dark ‘boa’ – the area behind that speckled pale thin collar, slightly weaker streaking on the breast and no dark shaft streaks on the undertail coverts. The central dark bar on the secondaries is obviously thinner and trailing edge of the inner primaries looks rather pale. The undertail coverts have no dark shaft streak. All subtle stuff. Which is why…

I learnt lots from this experience like:

– always beware of once-seen fly-by rare bird claims. Mistakes are common!

– blurry, distant photos won’t do when subtle features need to be seen

– while some juvenile Marsh Hawks are very distinctive, others will be very hard to identify unless seen/ photographed very well!

juvenile Marsh Hawk, Ian Lewington. What are the key features again?!

I chatted about this stuff with John Martin, Julian Hough and Alex Lees. Some comments:

from John Martin:
“As you say, the 28th August Spurn bird is clearly a Hen type on wing formula and could easily be the bird from 21st, which is presumably a juvenile Hen as it’s in Yorkshire in August. Both quite orange bodied but well within normal variation of juv Hen. The photos of the bird on 28th are way too poor to even think about a hudsonius claim on a bird like this – you just can’t see it well enough and with poor views streaky hoods can look solid, streaked underparts can look unstreaked etc – beware, this is crucial but perhaps not emphasised enough in the paper. The bird on 21st shows too much streaking and too streaky a dusky hood but you could get some poorly marked Northerns (Marsh Hawk) like this. Julian’s does show finer streaking more confined to flanks and close to the more solid hood. They can be tricky and you need decent photos. For some birds you probably can’t do them. Others however are really striking and don’t require quite such detailed images to nail them.”
from Julian Hough:
“I think it’s downright tough to nail one based on the plumage variation and overlap in many characters – without considering hybrids. The characters of juvenile Marsh Hawk from my experience:
– variable in underpart streaking – some basically unstreaked, some with breast band of streaks across breast and down flanks.
– boa variable in darkness, but typically giving hooded effect
– leading edge of underwing coverts usually unmarked and buffish and undertail coverts and lateral tail coverts unstreaked (typically streaked in Hen – not sure how reliable this is
– bands on P8 variable but as mentioned by you, typically 5-7 in hudsonius
– upperwing coverts and tail sides with warm rufousy edgings
– white at rear of eye often broken by post-ocular eyestripe, but this is matched by other harrier sp
– paler trailing edge to inner primaries
Basically all the features above are variable and seem to be matched by some cyaneus (see Spurn bird) which would likely be unidentifiable in the field. Birds in areas that have proven capacity for American vagrants (Scilly/Shetland/Cornwall) and where harriers are uncommon might indicate a better probability, but without close photos, identification will not be easily proven. Birds in late September -November also increase the probability as opposed to birds in August which stand a good chance or originating from more local populations.
I have definitely changed my thinking in the light of researching images and looking at individuals such as the Spurn bird to think that in most cases proving the occurrence of a hudsonius (even with photos) beyond reasonable doubt is probably an uphill battle. The Spurn bird wouldn’t get a second glance here in the US as a possible cyaneus since the characters are so close to hudsonius.”




11 thoughts on “Orange Juvenile Harrier

  1. Pete Mella

    Excellent post as ever – I got caught in the very same downpour that day, and afterwards two birders had said a possible Monty’s had gone past. Good to read the full story.

    Reply
  2. Julian Hough

    Martin/John

    I would like to add a little clarification that while most of the characters are close enough to be of limited use in the field and some overlap, I don’t want to throw the baby out with the bathwater as maybe my comments MAY have sounded. I think there is definitely merit in looking at the consistency of several features which may help cement good claims when the features can be analysed:

    – undertail covert streaking (absence of/presence of)
    – middle underwing bar
    – actual consistency of primary barring on 3 longest primaries of both Hen and hudsonius – how much REAL overlap if any, or how much consistency over a large sample size.

    I don’t recall seeing many hudsonius with the streaking appearing as far down or in the central belly area either, but again, without actually recording this on each bird it’s hard to classify.

    I’ll try and look at birds this week at my local migration spot…

    Reply
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  4. Steve Dunn

    Martin,
    I am pretty certain that myself, Mike Feely & Adam Archer were the first birders that day to see this bird. I can tell you that I initially picked this bird up c1/2 mile out to sea flying directly towards us (we were sheltering in the sea-watching hide). As it drew closer I announced juv Hen Harrier coming in-off. The bird drifted slightly north and passed the north side of the sea watch hide and headed towards the Canal area where we watched it as it appeared distantly to head out over the humber. With the bird being picked up so far out to sea, would that suggest that it maybe wasn’t the same bird that was seen a week earlier? I did comment on the rustyness of the bird but overall the jizz of the bird to our eyes pointed towards Hen Harrier. A guy then cam running past the hide screaming that a Montys was going thru and we informed him that we thought it was a Hen Harrier and left it at that.

    Hope that bit of info is usefull in some way.

    Cheers
    Steve

    Reply
  5. Archie Archer

    Martin, I’d say that the 28th August bird is different from the earlier Spurn bird based on the fact that I, along with Stevie Dunn & Mike Feely tracked it coming in off the sea from a hell of a distance out. As it flew past us in the sea-watching hide we all agreed upon juvenile Hen Harrier albeit a bird with orangey underparts. Soon afterwards a chap from the obs knocked on the window to say a Monty’s was currently flying up the Humber. We were pretty surprised everyone that day was claiming it to be a Monty’s based upon the decent views we had of the bird earlier! I did joke on the way home that it could have been a ‘Northern Harrier’ but it looks as though we will never know for sure. Putting the identification features to one side there was a deep Atlantic depression that swept over Greenland the week previous to this interesting harrier sighting. As we know, this probably helped bring over the vast numbers of Lapland Buntings into Scotland & the Northern Isles at this time. Could it have also displaced an inexperienced juvenile Northern Harrier I wonder?

    Reply
  6. Martin Garner

    Hi Steve and Archie

    Thanks very much for getting in touch. It does indeed sound like you guys were the first to pick up this bird. It’s just the nature of Spurn birding that a bunch of residents and very regular birders use radios = different ‘streams’ of info. Most birders I think only had very brief views – mine totalled about 5 seconds of the bird! So I think you had first views and very likely some of / if not the best views, making ID process a little easier – though personally I think juv/ female ring-tailed harriers should always be handled with care! In this case the brevity of views for many illustrated to me that inherent problem of brief fly-bys. Hope that comes through.

    Of course it could have been a different bird to the 21st- We just don’t know. As a small caveat – other larger birds of prey – Osprey, Marsh Harrier, occasional Red Kite routinely fly offshore running parallel with the peninsula. This Hen Harrier could have been doing just that and the sudden deluge pushed it toward land – what I am trying to say is that it need not necessarily have come straight across the North Sea – again don’t know. So it still could have been the same – or a second bird. Either scenario is feasible IMO.

    As to the possibility of early vagrancy viz. Marsh Hawk – I don’t disagree Archie – it is possible and it may be that we need to consider late August a viable time for more than Waterthrush, Waders and Warblers that are bright yellow! I see the finder of the juvenile Hooded Merganser in Cleveland last late August is appealing for a re-think

    Hey – next time you are at Spurn please look me up!

    Martin

    Reply
  7. Andrea Corso

    Hi Martin,

    interesting stuff about harriers…and I love Circus sp.

    Some short points to think about:

    1) Remeber always, that in any raptors species, female sport wider, broader, more diffused dark patterning, indeed in Falco sp. but also Circus sp. (see for ex. my note on monty in Dutch Birding or my papers on the web….if you whish i can send you the links) as well as eagles etc. etc. So that undertail coverts typically clean in males appear dark marked in females for examples in many species (I can refer here Falco subbuteo and F.vespertinus for ex., for which there are also published references but also often on Circus sp. , Falco biarmicus and so on) …same is true for “hand” trailing edge often more marked or wider in females, same for dark “hood”, for amount and extension of dark strekings/barrings etc. etc.

    2) Several Eurasian Hen Harrier do indeed show an obvious orange to orangish wash or tinge to underparts…I’ve seen quite a few, even here down to Sicily. See my very short note in Birding World several years agò, much before than most following papers on Marsh Hawk. There I reported some numbers for those birds in Sicily and Italy and a very much interesting picture too. I should have still slides somewhere of the Italian birds and of some skins.

    3) I found number of primary barrings far too variable, also in your bird…am I unable to properly count them ? In any case, also in skins I found quite a few birds overlapping.

    4) best character I found is the middle secondary bars

    5) hybrids of Hen x Pallid are a true challenging problem in Europe.

    Ciao

    Andrea Corso

    great blog compliments !

    Reply
  8. Andrea Corso

    Ciao Martin,

    some more feedback on Birdforum…

    Also, KM sent to me my short note back from 1999 in BW and rightly pointed out the the only photo there published (unhappy not about the Sicilian birds that I really have to find out on the huge caos of my home) indeed show 5 and not 6 bars on P9-P8 … as at the time back 12y ago I was counting the dark tip too…
    I wonder, in the Julian’s photo here reported, am I wrong or I can count only 3 dark bars on P10 (the proximal one being indeed the dark tip of PC) while 5 in P9 (the sixth proximal bar being concealed by the longer PC) and then on P8-P7 6 ?

    However, is the right time to go in museums and count all the dark bars in all the skins of Hen and Northern Hs. 🙂

    Thanks for your great blog Martin

    When your 2nd volume on Adavnced ID will come put ?

    Reply

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