More harrier stuff

The bird is still present this afternoon and has now been twitched by some local observers. Has caused a bit of a stir alright, not much time for musings from me here except to add a little more to the debate, including more third party comments I have received. Of course I myself am a little biased...Little negative feedback has yet appeared (apart from rumours some still doubt the i/d) but no response yet received from Dick Forsman on the prospect of hybrids.

Some new photos by Garth Peacock here

Many seem troubled by the strange upsurge in records from Tacumshin (6 birds in the last 3 years) and are wondering if Northerns could be interbreeding over here. It should be borne in mind Tacumshin is a mecca for transatlantic vagrants (often hosting several species at once, sometimes in numbers, such as the recent flocks of 26 buff-breasted sandpipers) and it should be remembered that all six harriers were found in October, the main month for yank vagrants. Is this not in itself a coincidence? Personally, I think it points to transatlantic vagrancy, in the same way two Eastern kingbirds have turned up out of the blue two years running on islands off the Galway coast. Maybe we'll get another next year?! And we do see changing patterns of occurrence with vagrants expanding ranges and shifting migration routes - RF bluetails increasing (from mega status to imminent 'relegation'), more yellow-broweds and Pallas's, herons slowly colonising from the continent, brown shrikes turning up increasingly frequently. I wonder what's happening with hudsonius in the US? The recent Northern harriers in UK & Eire have all looked the part whereas dodgy cyaneus have been around for a long time. For now we can look forward to DNA analysis of the current Tacumshin bird and the rumoured prospect of an imminent split. Gripping stuff! Watch this space...

from Martin Garner:

My gut reaction was that your bird looks remarkably good in overall appearance for hudsonius. More strikingly so in regard to head pattern, underparts colouration and lack of streaking and upperparts, than some others in W Europe in recent years which are also fine for hudsonius. I then went through the wing tip barring minutiae and came to the same overall conclusions as Killian, – I was (pro-hudonius) animated by 4 bars on p10 and fine for hudsonius on p9 and p8. I did wonder about  p7 and p6 on which there only appear to be 4 bars, as I thought there were usually more on hudsonius- but that is in part my ignorance and I need to look into that feature more.

More importantly for me the overall appearance is outside of that I would expect for cyaneus and so strikingly hudsonius –like, that I would rather explore the road of greater intraspecific variability in hudsonius than out it down as odd cyaneus. Repeatedly, understandably narrow criteria that have been laid down for ID purposes, subsequently get widened as we have discover more about the variation in closely related/ close-in-appearance taxa. So I think your bird looks like a Northern Harrier (I do like old ‘Marsh Hawk’) much more so than a European Hen Harrier. There will still be questions and learning, but I am envious of your find.

And from Brian Sullivan, author of several raptor I/D papers in North America:

Looks fine for Northern Harrier to me. Dark eye = female. Wing panels are the result of over-contrasted image in PS, but otherwise this bird looks typical to me.

Apparent NORTHERN HARRIER in Cambridgeshire

Well after that big dark peregrine recently I wasn't expecting another heart attack raptor so soon - but yesterday a hen harrier at the Ouse Washes with a dark hood and unmarked bright orange underparts really put the wind up me. It had been reported a couple of days earlier at a nearby location and put out by the news services as a possible pallid but then dismissed by another observer as a warm hen harrier. Now it was passing right in front of the hide I was in at the Ouse Washes. This bird looked to me bright orange below and more importantly, completely unstreaked - like a potential American race hen harrier (hudsonius, known as marsh hawk or now more commonly as Northern harrier) a difficult bird to i/d with records generally needing good photo evidence to show the relevant features that separate it from the many orange juvenile cyaneus hen harriers encountered.

My camera was in the car.

It was a fair walk to retrieve the camera but eventually I returned and settled down to wait. Luckily the harrier came back several times and performed well allowing me to get a good selection of shots. When I checked them however I wasn't sure the amount of barring on the underside of the primaries (4-5 on the longest ones) was sufficient for a Northern as I remembered 5-7 was the key number with P10 usually showing 4 or 5 not 3 and a bit as in my bird. In the mean time I got as many shots as I could as the bird passed back and forth causing panic amongst the thousands of wigeon and teal present.

So, could this bird be a Northern harrier? Back home I checked some references, looked at my notes on the 2 'marsh hawks' I saw in 2010 (in Wexford and Norfolk) and perused the photos more closely. Pro-hudsonius features include the well demarcated dark ear-coverts and hood and bright orange underparts (lacking streaking even on the undertail and present only very faintly on the flanks), fairly uniform in intensity but perhaps a little paler around the thighs and also extending across the underwing coverts; the bright coppery orange upperwing covert fringing (though appears more buff in some photos); the narrow middle bar across the secondaries apparent on this bird is also seen as a good pro-hudsonius feature. There were 4 - 5 bars on the underside of each of P7-9 putting the bird at the very edge of the range of hudsonius but fairly typical of cyaneus (a classic huds would show perhaps one extra bar on each). Other concerning features include the rather broad rufous eye crescents just about joined at the rear though their width and degree of connectivity behind the eye seems to vary with the angle of observation (should be narrow, whitish and clearly broken in typical hudsonius). The upperparts though dark do not appear as dark as in many classic hudsonius though as with most features this seemed to vary with the light. The bird was probably a female (later confirmed, see third party comments below) with the appearance of a dull yellow-brown iris but I knew I didn't have a full grasp of the variability of features between the sexes in juveniles. A number of features of this taxon are known to be more reliable in one sex than the other (Hough, 2011).

It is clear there are no 'magic feathers' for this form with no single diagnostic feature able to clinch a positive i/d and the criteria needed seems very much a 'work in progress' with both forms showing a range of variability with much overlap. 'Orange' cyaneus birds seem rather frequent and clearly cause a bit of a headache (though unlike this bird they usually have some streaking obvious). A combination of features need to be present and I was initially worried about the head pattern around the eye whilst the amount of primary barring seemed to me more in favour of cyaneus. Time to get in the experts, so I sought further opinion on these pics from several individuals with considerably more relevant experience than I have!

My intial thoughts were that this bird falls within the range of variation of both forms. It is not the first such occurrence and certainly won't be the last! Identification of orange ringtail harriers has never been more of a challenge with the issue of hybrid hen x pallid an increasing problem in the mix (one of these was present at nearby Ouse Fen fairly recently). Apparent 'good' Northern harrier records are on the rise this side of the Atlantic and remarkably this taxon now appears annually at Tacumshin, Co Wexford (all juvs too so not even returning birds) though there are still only three accepted British records. I do think however there are too many unanswered questions regarding this form which does not appear as diagnosable in the field as once thought. It appears that advanced level identification of many birds across the board tends to lead to muddy waters and more unanswered questions just as we think we're getting to grips with them. Perhaps it's better just to kick back and enjoy the bird rather than get bogged down in the minutiae of exactly what form it is and where it's from!

Update: Or perhaps not? I've just received the following very positive comments from Killian Mullarney:

Having now had a little more time to examine them a number of points are clear.

 

It is a juvenile, and with such a dark eye, definitely a female.

 

It has just five bars on the longer outer primaries (which is common in both hudsonius and cyaneus).

 

It has a faint hint of a fourth  bar on the outermost primary, just outside the dark-tipped under primary coverts. This is not so exceptional in juv male cyaneus, but it may exceptional in juv female. It is typical for hudsonius to have four bars on p10, the innermost sometimes faint, as in your bird.

 

I can discern no streaking whatsoever on the breast, flanks or underparts. While it is possible that even closer-range images will reveal some very fine streaking, such a complete absence of visible streaking at the range of your observations appears to be outside the variation seen in cyaneus.

 

The neck (collar) is certainly darker and more heavily streaked than the vast majority of cyaneus but appears to be perfect for hudsonius.

 

The overall darkness of the head and neck, contrasting strongly with the bright rufous-buff and essentially unmarked underparts is typical of hudsonius. It does not look quite as dark as in many hudsonius, but I'm not aware of any evidence that cyaneus can appear as dark, and have as subdued streaking as in your bird.

 

The apparently rather dark upperwing coverts and very distinct and extensive pale cinnamon markings on the lesser and some median coverts appears to match what is much more usual in hudsonius than in cyaneus; I'm not sure if cyaneus are ever as well marked as this, but I don't think I have seen one with such prominent, extensive and bright patches on the upperwing.

 

The clear-cut and very dark centres to the axillaries and greater underwing coverts contrasting with the paler rufous-buff and unmarked median and lesser underwing coverts is a strong pointer to hudsonius.

 

One point that may not be of any significance, but in most hudsonius the bright apricot-buff colour of the underparts looks 'smooth' and even; in your bird there is a slight blotchiness that I cannot recall having seen in the any images of hudsonius I have studied.

 

There may be some other points that will occur to me later, but I think the combination of features shown by your bird is strongly indicative of it being another Northern Harrier.

 

Why are we suddenly recording this previously ultra-rare taxon so frequently over the past four years or so, in Ireland and Britain? I really don't know. Obviously there are concerns that the established identification criteria may underestimate the potential for some cyaneus to match the appearance of hudsonius much more than is currently known, but this seems unlikely. There are also concerns that the reason we are suddenly seeing so many hudsonius is that a number of birds that made the transatlantic crossing a few years ago are now breeding (with cyaneus?) on this side of the Atlantic. I guess it is possible, but so far there is no evidence for this, and one might expect there to be at least as many indeterminate or intermediate-looking birds as perfect-looking examples?

And from Julian Hough:

If the bird is dark-eyed as it looks in the image, and it is a female, it would dispel my concerns about the lack of streaks on the upperbreast and flanks and the middle secondary bar. Lack of streaks is good for female hudsonius. Female hudsonius also have a tendency to show more uniform vents - males look uniform at a distance but close up they have thinner, slightly darker shaft streaks. Females also tend to show fewer bars on the primaries than males in a small sample size i looked at from birds banded at Cape May. Also, they tended to show a thicker middle secondary bar compared to males, which again fits with your bird, as does the darker greater underwing coverts. 

One picture on the ground seems to show a rather saturated and warm bird!

These ones actually convince me a bit more than the close-ups! The blurry topside shot clearly shows what appears to be, if I saw it here, a typical Northern Harrier! 

I just saw Killian's email on the crops and his notes about the eye color which he believes shows a female too. In the field, a bulky bird with broad wings would back this up, as opposed to a smallish, narrow-winged male.

I feel weirdly cautious but can't point to anything that doesn't fit Northern based on the images which build a better composite of the bird. 

References:

Nils Van Duivendijk: Advanced Bird ID Handbook (2011)
Hough, J: The 'Marsh Hawk' Conundrum  http://naturescapeimages.wordpress.com/2011/01/25/the-marsh-hawk-conundrum/
Martin, J.P: Northern Harrier on Scilly: New to Britain http://www.britishbirds.co.uk/search?model=pdf&id=9402
Wallace, D.I.M: American Marsh Hawk in Norfolk http://www.britishbirds.co.uk/search?model=pdf&id=4478

Classic East Coast Fall - The Perfect Storm?

These days it's easy to think all the best birds turn up up north. The Northern Isles get the Lion's Share and the NE coast fromYorksire up seems to run away with most of the mainland birds. Yet if the conditions are right East Anglia and the South-East can still get in on the action. The classic 'fall' conditions everyone awaits in the Autumn is an area of High Pressure over Scandanavia and a Low moving into the Southern North Sea/ low countries bringing east and north-east winds and plenty of rain. The Scandanavian high encourages mass migration south and as the migrants meet poor weather over the North Sea they are driven across it where disorientated they make landfall on our east coast. The position of the jet stream usually ensures these lows pass too far to the north but last week one came right across East Anglia and the South-east, delivering several days of optimal weather and great birds! For once the forecast was right and I eagerly anticipated my day in Norfolk which materialised on the sunday (I only wish it could have been longer).

Mark and I started at Holme, a location which had been kind to us last year when I discovered a rose-coloured starling on Lavender Marsh. We concentrated on the area around the start of the track and Redwell Marsh. Singer and birder David Gray has a home here and I've seen some good birds at this spot, including collared flycatcher.

It was a wet and windy start which made for challenging conditions to search in. The previous day had seen many great grey shrikes and Pallas's warblers turn up and the first parrot crossbills had made an appearance too. It took some hours of searching but eventually a Pallas's piped up close by but it called just once and never revealed itself, leaving us wondering if we really had just heard one. I even wondered if we had heard a freak squeaking branch! But later on one was found just 100m from where we'd heard ours and the following day it was at the very same spot we had been at, so it now seems unlikely our bird could have been anything else.

News of a bluethroat on the reserve sent us off down the track but the bird was highly elusive. In 2 hours I managed only a brief view of it through the chicken wire of a Heligoland trap (it was on the wrong side but was trapped the following day). A great grey shrike showed distantly on the grazing marsh and another flew over, looking like it had just arrived 'in off'. A few mealy redpolls and wheezing brambling were in evidence and robins and thrushes were present in high numbers.

We headed off about 4 as the weather was deteriorating. With hindsight a slightly earlier departure and trip to Wells would have been a good bet to finish on but we did OK. Just a shame that Pallas's didn't show!

Three days later and the fall was still in evidence from my home in South Cambs. Redwings passed over and a woodcock flitted across the end of my road and sought refuge in the back yard of a car dealership. I followed it in the car and snuck into the yard not knowing what to say if I was challenged, but it had disappeared, perhaps hiding underneath one of the cars. A decent woodcock photo will just have to wait.

Yesterday I found myself 10 minutes away from Grafham so called in to see the juv bonxie present. It showed well at the same spot the sooty shearewater was previously and a juv long-tailed duck was easily located off Mander Car Park at the other end of the reservoir.

Frustration on Shetland and a Dark Shadow over St Abb's

On Tuesday, with Mark and Dave, I visited St Abb’s Head for the Sardinian warbler on my return from Shetland. We had already missed the trip target (thick-billed warbler) and at St Abb’s we added the skulking Sylvia to the dip list! A takking lesser whitethroat tried its best to convince us and a yellow-browed remained unseen in a clump of sycamores. It was my first visit to this site and I remarked as we waited for our quarry that all would be forgiven if an Eleanora’s flew over, a bird I could well picture at this setting in October.

Perhaps 25 minutes later a large dark falcon rocketed through the valley.
 

From the very first glimpse I was convinced from its structure (chunky with fairly short wings) it was nothing more than an exceptionally dark (melanistic) juvenile female peregrine. I fired off some shots in the seconds it was in view and a quick analysis of the photos later failed to change my mind. Yet it was scary and needs highlighting. Surely such birds could be the source of some of our claimed Eleanora’s?

So what of the Shetland trip? Though the original target is now perhaps best forgotten, we did get in a weekend’s birding, the highlights of which came in the form of an Eastern olivaceous warbler at Hoswick and a short-toed lark at Sumburgh. I found a probable Siberian chiffchaff in Lerwick which failed to call and we came across yellow-browed warblers (in 1’s and 2’s) at just about every location we checked. Other highlights included merlin, male redstart, whinchat and common crossbill.

Eastern Ollie, with less than 20 British records, still holds on to its MEGA status and this individual represents my second in the UK and my first for more than 18 years. This bird often showed very well but
unfortunately I had wandered off when it gave prolonged views for 5 minutes or so in the sunshine! I did manage however a view of it sat out in the open for maybe 10 seconds so can’t really complain.

The Sooty Show & Incredible Edibles

A packed Thursday saw me up at 3.45am to help out with a bat survey and I used the opportunity to do some birding as well. A juvenile red kite and a few green sandpipers provided the highlight at Ouse & Berry Fen and later I had a first in the form of some sexton beetles beneath felt at Mildenhall - larger than I'd imagined and covered in some parasitic mite, perhaps from the body of an unseen victim.

Stone curlew numbers were down on last week's visit (probably as a result of the differing time of day) but a woodlark overhead was only my second record at this site.

It was on to Cambridge for a three course meal at a restaurant with some friends but when news broke mid afternoon of a sooty/ balearic shearwater at Grafham I hastily made plans to visit. A couple of hours later I was there, watching what is likely to become the first ever accepted record of an inland sooty shearwater in Britain. The only previous contender was a bird in 1988 at the same site - removed after a review last year which concluded balearic could not be ruled out from the evidence available.

The bird showed well off the dam down to about 50m or so and I heard after I left it drifted right up to the shore. It wasn't seen to fly and was probably unwell. There was no sign of it the following day. Bearing in mind this is a southern hemisphere species perhaps it's not a wonder that it never seems to turn up inland but rather that is shows up in such good numbers on seawatches at all. At this time of year sooties can be seen in their hundreds at the right locations and with the right weather conditions (though my personal best is a rather more modest 19!)

Moving back to mammals and last night saw me take a little sojourn down to Wendover where the edible dormice showed very well. They were there when I arrived at dusk and soon the woods were alive with their little calls, the odd individual posing in the beam of a torch. These mammals (often known by their scientific name Glis glis, or a shortened version, simply Glis) have been around since last century when they were introduced to Tring Park and though they haven't spread far they have certainly built up a respectable population density. Non-native invasives they may be but cute they most certainly are too - unless you live in one of the homes they choose to invade (over 400 have been found in a single loft before).

19th-20th September

A busy couple of days saw me help out with a couple of surveys and sneak in a bit of batting and birding too. On the 19th I popped in to Ouse Fen where 5 or 6 hobbies were sat around on posts along Cuckoo Drove. They included an obliging 2nd calendar year bird sat close to the main track. A little later a bittern showed in flight. It's not quite the Somerset Levels or Minsmere but this species is seen now on most visits to the site, proving they're going from strength to strength in the county.

That evening I joined some bat catchers at Grafham. It was quiet but we caught an adult female brown long-eared. There were a good few pips about and we glimpsed a Myotis spp, a Natterer's or Daubenton's (I also think I had Natterer's at Over Village earlier in the evening). Tawny owls were vocal at both sites. I got home about 12.40am.

The following day I called in to Lynford Arboretum where two young male two-barred crossbills were showing well with at least 8 common crossbills. Going through my photos afterwards I noticed a juv female next to one of them - how did I manage to miss that in the field?!! Strangely a tawny owl was vocal here too, despite it being mid afternoon!

On the way home I called in to a traditional stone curlew site and counted an impressive 65+ birds. I pay about one visit a year to this location and last year counted an astonishing 88 individuals, though I believe counts of over 100 have been made as both adult and juvs gather from miles around before embarking on their journey south.

September livening up!

Last week was a busy one. A pretty awesome weather forecast for a Norfolk seawatch on Tuesday failed to deliver the goods, though I did manage 2 or 3 sooties, a black tern and a puffin from a 2.5 hr seawatch off Sheringham. I also paid my respects to the dodgy sparrow at Northrepps - put out as a possible Italian, but notably lacking any white around the eye and perhaps more likely to be an erythristic house sparrow or a hybrid.

On Thursday it was an early finish at work to bomb down to Oare Marshes for a spotted crake. This bird showed like a dream, giving great views down to 7 metres or so. The scrape offered excellent views of a wonderful array of waders which included at least 7 juv curlew sands and 4 little stints. An impressive flock of 1,000+ redshank was also present.

Torrential rain on Friday night failed to dampen my enthusiasm for some local mammal trapping at Fowlmere and it certainly didn't keep the rodents away either. A total of 15 wood mice were trapped, with 2 bank voles, 2 common shrews and 3 yellow-necked mice. One wood mouse escaped in Doug's hut and another ran all over Mark before ending up on his head where it launched itself high into the air and made good its escape!

I've only seen one great snipe, on my London local patch at the age of 14. Views were poor with just the head visible above grass in the fading light of dusk. It's always been the one and only bird on my list with less than spotless credentials. I knew I needed to see another and on Sunday I got the chance. One had turned up at Kilnsea, Spurn, the previous day, and to my surprise was still around the following morning. It was time to Fire up the Quattro though in the event I left the Type-R behind and borrowed Liz's slower but more economical Skoda! I collected Robert Smith at Stamford and continued north to Kilnsea, arriving at around midday.

The bird was showing on arrival and wow, was it showing!! I hadn't realised just quite how close people had been getting to this one. A small crowd on the verge were staring into a roadside ditch and there, just metres away, was a very unconcerned great snipe! Just occasionally rarities turn up which have little or no fear of people and those twitches can fast become all-time classics. Last winter I got within 2 metres of the 'pet' buff-bellied pipit at QMR and within a metre of the Suffolk Hornemann's arctic redpoll; pine grosbeak, lancey, isabelline wheatear and yellow-rumped warbler have all allowed me to grill them to a few feet in the past.

Now the irony of this twitch is that I'd left my camera at home! It was a deliberate but stupid move as I thought on this occasion digiscoping would suffice. Digiscoping turned out to be extremely difficult and I ended up inserting my memory card into Robert's bridge camera to get some shots. At one stage the snipe got spooked by something in the ditch and flew out of it towards the crowd, landing just 2 metres in front of me - amazing! It scuttled off and re-entered the ditch a few metres further down, where it started to poke around a discarded can of Strongbow.

A barred warbler residing 100 yards along the road was a handy bonus bird but I had to return to the mesmerising snipe which by now was snoozing in the grass in the corner of the field the other side of the hedge. After a while it had a brief preen and ran back to the ditch and eventually we managed to tear ourselves away.

There are more records of great snipe than any other BB rarity but it remains a tough one to see, with most of the 2 or 3 annual records coming from Shetland. Many are only seen in flight after flushing so to get one like this is all the more remarkable. Long live the Kilnsea great snipe, a true birder's bird!

STOP PRESS - The snipe was found dead on the morning of 17th, thought to have been killed by a cat. A sad end to a wonderful bird and an unfortunate sentence to finish with (above). RIP.