Rockin' around

There's a Blue Rock Thrush in Gloucestershire at the moment. It's origins are up for debate and, as with every debate on origin, the age of the bird has come under scrutiny. I have to admit I'm not sure age really makes that much difference with some of these vagrants – and I'm staying out of the origin (and indeed subspecies) debate – but, since there seems to be some confusion over the age of this individual, I thought it was worth cobbling a few words on the subject (and cobble is the right word, since I've been keeping track of most of this debate on my phone from a delayed train heading back to London and haven't long been back at my desk). Initially, observers were calling the bird a 1CY ("first-winter"). I posted on Twitter yesterday to say the bird looked like an adult, and subsequent reports on the news information services went out as such. Today, though, I see opinion has swung back to it being a first-winter. A few people have been wanting to know why I aged the bird as I did, so here are my reasons for why the Gloucestershire Blue Rock Thrush is an adult:

First of all, as always, let's start with the moult of the species. The species has a partial post-juvenile moult in its first year and a complete post-breeding moult in subsequent years. In that respect, moult strategy is as in Dusky Thrush. Per BWP, the partial post-juvenile moult includes "head, body, lesser and median upper wing-coverts, occasionally tertial coverts (4 of 20 examined), and rarely some inner greater upper wing-coverts or central tail-feathers". Don't worry about what the tertial coverts are; you'd need to go rummaging around for them even if you had the bird in your hand. From a practical point of view, that moult means on a first-year bird we're likely to be able to see a moult limit either between the median coverts and the greater coverts, or within the greater coverts themselves. It also means, since birds have just one moult a year, those moult limits won't change until the bird undergoes its first complete moult after breeding in its second calendar-year. Blue Rock Thrushes don't moult primaries, secondaries or primary coverts during the post-juvenile moult, so they will always offer helpful clues to the ageing regardless of the extent of the rest of moult. BWP matches with my observations from photos that the moult in this species is usually quite restricted (e.g. just one or two GCs moulted, and thus 8 or 9 old greater coverts retained) but Svensson (1992) hints that some birds may be able to moult all GCs. If that were the case, a moult limit would be between the greater coverts and the always-retained primary coverts, primaries and secondaries.

So, what can we see on the Gloucester bird? This post on BirdForum seems (from what I can gather) to be the reason for the age switching from adult back to first-winter. I agree, the linked photo shows an apparent slight difference in colour across the greater coverts but this is not a moult limit. It's simply light reflecting off the central greater coverts in a way that makes them look paler than the inner – and outer – coverts. There are plenty of other photos of the bird that show the greater coverts to be uniform all the way across; see below photos by Lee Fuller, for example, and multiple examples elsewhere online.

Adult male Blue Rock Thrush, Gloucestershire, December 2016 © Lee Fuller

Adult male Blue Rock Thrush, Gloucestershire, December 2016 © Lee Fuller

Adult male Blue Rock Thrush, Gloucestershire, December 2016 © Lee Fuller

Adult male Blue Rock Thrush, Gloucestershire, December 2016 © Lee Fuller

The greater coverts are all of the same generation, but are they all adult or all juvenile? First of all let's look at the base colour, which is deep black across the entire feather tract. In 1CY birds the base colour of the GCs is brownish. Secondly, the feather fringes are deep solid blue, and rather broad. Young males can show some blue to the feather fringes but it's duller, paler and thinner to the point that it often wears away by spring. See e.g. here and here, and also here for examples of young males. I'm not sure when the first two photos were taken, but the third bird is a 2CY ("first-summer") bird in early summer. That individual has helpfully dropped and renewed one of the central greater coverts. Despite the high level of wear across the entire feather tract, contrast between the retained juvenile GCs and the renewed central GC is still visible and the black base-colour and broad blue fringe to the renewed GC is apparent. The median coverts of the Gloucestershire bird show the same adult-type pattern as the greater coverts. Per references and observations, first-year birds always moult their median coverts, so a bird with retained juvenile GCs would show some contrast with the adult-type MCs, which we don't see in the Glos bird. All the median coverts and greater coverts are adult-type, but perhaps this bird is one of the rare (theoretical?) individuals that has moulted all greater coverts during its post-juvenile moult. The same black base-colour and blue fringing as shown by the GCs is present across the the primary coverts, the tertials, secondaries and primaries (see e.g. here); the entire wing is adult-type, a sure sign that the bird must be a 2CY+ (adult) bird that has undergone a complete post-breeding moult, and not a first-year ("first-winter") bird which would have retained at least its juvenile primaries, secondaries and primary coverts, which would contrast with any moulted flight coverts. There is also no contrast between the body feathers (which are always moulted during the post-juvenile moult) and the flight feather; the paler blue fringes to the wing feathers in first-years contrast with the deeper blue of the moulted adult-type body feathers; in adult birds, the shade of blue is uniform across the whole bird, as in the Glos bird.

Even if the bird can be safely aged as an adult on these features alone, it's worth checking that all the other features fit. The tail feathers on the Glos bird are broad and rounded, and also the same generation as the wing feathers (and body feathers). Primary shape is good for an adult, as is tertial shape and primary covert shape. Overall, this bird looks in fresh condition with no obvious wear or bleaching; you'd expect a first-year to be more worn around the edges by now regardless of origin. As an additional "don't put too much weight on it but it's worth mentioning anyway" feature, the bird's iris looks to be particularly warm-brown; in most first-year passerines the iris is a darker greyish-brown, although this is heavily dependent on light conditions and can vary both between and within species.

There's one thing I've deliberately left till last, and that's the white tips to the greater coverts and primary coverts. I've repeatedly seen reference to the pale-tipped GCs as evidence that the bird is a first-year. Yes, pale tips to the greater coverts are indicative of immaturity in some species but in other species, including Dusky Thrushes as discussed in the previous blog post, a pale tip in itself is of no use as an ageing feature. And just as with the Dusky Thrushes, Svensson's Identification Guide to European Passerines is a great starting point for attempting to age this species. Svensson says of adult Blue Rock Thrush, "All GC uniformly fresh, tipped white and edged blueish... ...Primaries and PC dark, fresh and glossy, very narrowly tipped white." He says of first-years, "Primaries and PC slightly worn, sometimes rather broadly tipped buffish-white or off-white. In some, outermost GC unmoulted, edged dull brown and contrasting with fresh inner [GC], edged as in adult". I've added the bold text myself. There's even a figure to go with the description of the primary coverts:

 
Blue Rock Thrush primary coverts, from Svensson (1992).

Blue Rock Thrush primary coverts, from Svensson (1992).

 

For me, the Gloucestershire bird – with its neat, thin, white tips to its blue-edged primary coverts – matches Svensson's description and figure for an adult male near-perfectly. Combined with the other characteristics mentioned above, I have no doubt that the Gloucestershire bird is an adult.

And for anyone who wishes to purchase a copy of Svensson's Identification Guide to European Passerines, you can do so from the BTO. £20 of any birder's money well spent!


Edit: 13/01/2017 Since I posted this blog post, debate over the Blue Rock Thrush’s age has continued. Rather than engaging in these debates on Twitter (where the 140-character limit simply isn’t enough to give an unambiguous explanation of subtle features), I thought I would address some of the issues I’ve seen raised with an edit to this blog post.

As a general overarching point with this bird – and others – I’m perfectly happy for people to have questioned my conclusion. It forces me to go back and critically assess the assessment I’ve made. I have to admit though, the more photographs I see of this bird, the more satisfied I become with the conclusion of my initial assessment.

Moult limit (1): I’ve seen several further mentions of a moult limit in this bird, based on the photograph that’s linked from the BirdForum post that I linked to in my original post above. My opinion on this hasn’t changed but it’s worth stating again that this apparent moult limit is, in my opinion, a trick of the light. Assessing a moult limit from a single image can be misleading and this apparent moult limit is not visible in any other photo of this bird.

Undertail coverts: I’ve seen some argument that the buffish fringes to the undertail coverts on the Glos bird make it a first-winter. At least some of this seems to have stemmed from a misunderstanding of text in Svensson (1992) that says, regarding sexing characteristics, “Applicable after post-juv. moult, which takes place in Jul–Oct.” and goes on to say of males, “Chin and throat bluish, tinged grey in fresh plumage. Under TC bluish-grey, tipped buffish-white and with dark grey subterminal marks.” The confusion seems to have arisen from the phrase “applicable after post-juv. moult”, which appears to have erroneously been taken to mean “birds in first-winter plumage”. In this case, “after post-juv. moult” is not referring to the plumage acquired immediately after the post-juvenile moult but rather any plumage after the post-juvenile moult; that is to say, these characteristics are not applicable in juvenile plumage but they are in all subsequent plumages. 

With regards to the undertail coverts themselves, it had been argued that adults show white fringes to the undertail coverts and first-winters show buff fringes. Unless I’ve misunderstood something, the birds on which this feature has been assessed appear to have been aged using the criteria laid out in my original post detailing why I believe the Glos bird to be an adult. An assessment of the undertail coverts on these birds seems to have been made, and that assesment applied back to the Glos bird; the same Glos bird that was originally the basis for the ageing criteria used to age the birds where undertail coverts were assessed. The result, as far as I can see, is a cyclic argument where the two joining ends of the circle are at odds with each other.

I haven’t studied the undertail coverts on this species with regards to ageing in detail myself, so this is one area where I will say that I don’t know for sure, although with a quick Google search it wasn't difficult to find e.g. this bird, a clear 1CY in October with, to my eyes, whitish tips to the undertail coverts; or this bird, a 2CY in May with buffish-white tips to the undertail coverts. My general impression of European/Arabian Blue Rock Thrushes (and the European/Arabian bit is important in this sentence) is that the underpart fringing is generally the same from the breast to the undertail coverts. Regarding the Glos bird, my impression of the breast and belly feathering is that it is fringed buffish-white with a dark subterminal band (see e.g. here). The undertail coverts of the Glos bird are, in contrast to the breast and belly feathers, fringed a much richer buff-pink or pale buff-orange, depending on which photograph you look at (see e.g. here). This strikes me as a feature which is more than likely related to the orangy/pinkish/rufousy outer webs to the outermost row of undertail coverts; and this in turn I’m sure must surly be a clue towards the subspecific identity of the bird, not the age of the individual. A colleague of mine analysed a large number of photos of Blue Rock Thrush from Spain and none showed any rufous-toned in the undertail coverts. It’s been reported that European birds can show some rufous on the undertail coverts but, if that’s correct, it must be extremely rare. From a very quick Google search when this bird first turned up, birds labelled as pandoo appear to be able to undertail coverts matching the Glos bird, although it seems this characteristic is variable – or at least not well studied and catagorised. On a similar note, this bird constantly gives the impression of being darker and more ultramarine in colour than European birds. Even in the field, European birds can look anything from powder-blue to almost black, so I'm being cautious in my assessment of the colour of this bird. Still, it's something to consider.

Alula: It’s been stated that this bird can be “conclusively aged as a first-winter” by the brown alula. This one is actually hard for me to argue against for the simple reason that I cannot – no matter how hard I try – make the alula on this bird brown.

Tail feathers: It’s been stated that the “tail feathers look pointed in flight images”. Again, I struggle to argue against this other than to point people towards photos such as this one, which show a good square-on image of the tail feathers and which, to my mind, are most definitely not pointed.

Moult limit (2): I should thank Gareth Jones for contacting me and passing on a link to his blog (scroll down to the bottom of the page), which includes comments from Javier Blasco on the age of the Glos bird: “these are not easy birds for ageing using photos since moult limits are not very clear. I enclose one of your photos [reproduced below] with one arrow pointing to that I think it is a moult limit in inner Greater Coverts .. if I am right then it is a 1st year male. But people who are arguing for an adult bird have good reasons too with a bird so fresh and having some bluish tinge in coverts and flight feathers. So .. I vote for 1st year but not 100% sure ... so send my opinion for other colleagues to consider if my argument is right or wrong.”

My response to Gareth was as follows: I respect Javier’s views on these matters but I do not believe the arrowed greater covert represents a moult limit. The inner greater coverts can often be slightly more protected from wear/bleaching, and on some species can show a subtly different pattern such as this. I’ve spoken to colleagues in Spain, who handle and see numerous Blue Rock Thrushes, and they have confirmed that a “false moult limit” such as this can sometimes be detected on adult male Blue Rock Thrushes. Additionally, there is no difference in colour between the arrowed GC and the tertials and secondaries. If we say, for argument's sake, that the GC had been moulted, we would expect to see a contrast between the adult-type GC and the retained juvenile tertials and secondaries. In this bird there is no such contrast within these feather tracts, which points to the tertials and secondaries being adult-type too. Only an adult bird would possess adult-type tertials and secondaries, since these feathers are never moulted during the post-juvenile moult.

Not particularly related to the age of this bird but something I was asked about: The apparent ‘thread’ around the bird’s leg in relation to the bird’s origin. I’ve seen adornments like this occasionally on wild birds caught for ringing – from Goldcrests to Blackbirds. It was actually relatively common on Goldcrests where leg bracelets like this often seemed to be composed of spider webs and pine resin. On other species the composition varied; mostly various fibres, sometimes bound together with dried mud etc. So, in terms of indication of origin, I'm not sure this apparent thread around the leg holds any weight on either side of the argument.

Finally, I’m always of the opinion that my arguments should stand on their own merits. However, it’s worth adding that I’ve spoken to several birder-cum-ringers with a particular interest in ageing birds in the field, all of whose opinion I respect greatly. All have agreed that the Glos bird is an adult for the same reasons as detailed in my original blog post. 

Dusky Thrushes

I posted some comments on Facebook the other day in relation to ageing and sexing Dusky Thrushes. The comments were prompted by a photo posted by Pete Morris and the discussion resolves around that bird, a photo of a bird posted by Steve Rooke, and the Derbyshire bird. Although the comments were very much intended to add some interest to the Facebook thread and not particularly go much further, I've seen a few people mentioning them since and asking where they can see them. With that in mind, I'm copying and pasting them here, where they should be more accessible for those who don't have Facebook or the relevant "friend connections" to view the original post. Give the copy-and-paste nature, you may have to infer context in a few places. I'll thank Pete, Steve and Mike Watson in advance for having nabbed their photos and posted them here.

2cy ("first-winter") male Dusky Thrush, February © Pete Morris. This bird is referred to in the discussion below as "Pete's bird"

2cy ("first-winter") male Dusky Thrush, February © Pete Morris. This bird is referred to in the discussion below as "Pete's bird"

3+cy (adult) male Dusky Thrush, January © Steve Rooke. This bird is referred to in the discussion below as "Steve's bird".

3+cy (adult) male Dusky Thrush, January © Steve Rooke. This bird is referred to in the discussion below as "Steve's bird".

Since discussion on the Derbyshire bird seems to have centred itself [on this Facebook threat], I thought I'd add my comments on this bird (and the two males above). I'm in the office at the moment and had planned to write a few short words but, well... Sorry Pete Morris for taking up half your Facebook wall!

First, the two males discussed here. For me, Pete's bird is a 2CY (first-winter) and Steve's bird is an 3CY+ (adult). The photos are taken at more-or-less the same time of year, so the wear on the two birds can be compared. Dusky Thrush undergoes a complete post-breeding moult and a partial post-juvenile moult, both undertaken on the breeding grounds. There's no further moult until after the following breeding season, so any retained juvenile feathers following the partial PJM will be retained throughout the bird's first winter.

In addition to the overall higher level of wear on Pete's bird (though see my comment on the greater coverts below), I've tried to focus on structural and plumage features that aren't too affected by time of year. I've focused on four features, which I detail below.

– Primaries. As it happens, I'm currently writing up a short note on ageing passerines using primary shape, with thrushes being a good example of a species where it can be particularly useful. Juvenile primaries are generally more narrower and/or rounder at the tip; adult primaries are broader and ofter more squared-off at the tips. Pete's bird shows rounded-tipped primaries, perfect for an immature bird. In contrast, the primaries on Steve's bird show a bit of an 'angle' to the outer web. You kind of have to take my word for it on this one, but the shape matches what I'd consider fine for an adult. The innermost visible primary may be an odd accidental loss. Sometimes primaries covered by tertials are considerably more protected than exposed primaries and there can thus be quite a contrast between the two, although the contrast here seems too strong for that. The level of wear and extent of fringing between the primaries on these two birds is also in line with expectations for immature vs juvenile. The difference in pattern, too, seems to be age related with immature birds showing a concentrated orange area at the base of the primaries and adult males showing orange extending much further down the primaries.

– Tertials. As with the primaries, there is a similar difference in shape between juvenile and adult tertials. Pete's bird shows rather narrow, quite rounded tertials; Steve's bird show much broader tertials in comparison. Again, the angle of the photo isn't great for assessing this, and this also comes with the caveat that the tertials could theoretically (but probably in reality very rarely) be moulted. Nonetheless, evidence points again to immature vs. adult.

[Edit: As is typical, it wasn't until I hit send that I noticed the inner tertial on Pete's bird, which appears to be adult-type. It's subtly broader than expected for a juvenile feather, has the same thin white edge as in the moulted GCs, vs. the more extensive and more diffuse pale tips to the juvenile middle and longest tertial, shows a more defined contrast between the black and the orange, and has an orange colour that matches that of the moulted adult-type GCs but contrasts with the paler orange or the unmoulted middle/longest tertial, unmoulted GCs, and secondaries/primaries. This doesn't change any conclusions but it does add another piece of evidence to the suite of characteristics that age this bird as a 2CY. It also proves the point that moult limits in thrushes can be subtle!]

– Primary coverts. My own assessment of this matches what's already detailed in Svensson (1992; Identification Guide to European Passerines), which is actually a great starting point for anyone wanting to age a bird, even in the field. In immature males, the dark tip of the primary coverts runs up the outer web of the feathers such that the dark tip on the closed wing is rather diffuse. On adult birds, the black tip is restricted in how much it extends up the feathers, and thus the dark appears on the closed wing as a neat black tip (as in Steve's bird). This is perhaps the most obvious ageing feature for a (male) bird in the field, since moult limits (esp. in the GCs, see below) can sometimes be subtle in thrushes.

– Greater coverts. I think there might be too much weight being put on the white at the tips of the greater coverts. Certainly, it appears to be more extensive on immature GCs but it doesn't seem to be as clear-cut as white/no white. Pete's bird shows a moult limit in the greater coverts, with the outer four being retained juvenile coverts. The most obvious difference between the two ages of feathers is the overall ground colour – paler more wishy-washy orange on the juvenile coverts. Notice that the white tip is more extensive, extending some way up the feather, and also more diffuse. Comparing the GCs to the rest of the wing in general, there is a contrast between the moulted inner GCs and the orange of the tertials/secondaries/primaries/primary coverts. There is no contrast between the retained juvenile greater coverts and these feather tracts, with the same orange tones across all of the retained juvenile feathers. In contrast, there is no moult limit visible on Steve's bird, neither in the GCs themselves nor between the GCs and the rest of the wing. Indeed, all of the flight feathers are a much richer orange-brown, matching in colour the moulted adult-type inner GCs on Pete's.

I said above that there was a "see below" on the wear of the greater coverts. The inner greater coverts on Pete's bird appear to be quite worn around the edges and may suggest worn juvenile feathers. All of the other evidence available points to them being moulted adult-type feathers and I suspect this bird has has a scrap with a thorn bush at some point. Indeed, one of the primaries is pretty mangled and while that is a juvenile feather, that level of damage wouldn't be expected from general wear and tear.

One final point on these birds: as is often the case, Killian's illustration in the Collins Bird Guide go way beyond what is stated in the text and annotations. The differences in for example primary covert pattern, primary colour, and greater covert pattern, have all been illustrated perfectly!

1cy ("first-winter") female Dusky Thrush, Derbyshire, December © Mike Watson

1cy ("first-winter") female Dusky Thrush, Derbyshire, December © Mike Watson

So, for anyone still with me, moving to the Derbyshire bird:

– Primaries. The primaries on the Derbyshire bird are extremely narrow, almost pointed. This is entirely typical for an immature bird.

– Tertials. The tertials, too, are narrow and entirely typical for an immature bird that has retained juvenile tertials.

– Greater coverts. The greater coverts on the bird's left side are all uniform with not apparent moult limit. This could mean one of two things: they're all juvenile or all adult. Overall, base- and fring-colour of the wing in general looks rather uniform, suggesting the greater coverts are the same generation as the primaries, secondaries and tertials (i.e. juvenile). Turning to the bird's right side, GC9 (second-from-innermost) has been moulted (slight asymmetry isn't too unusual) and shows a clear difference in base colour, fring colour and length from the neighbouring GCs. It also contrasts with the primaries/secondaries/tertials, confirming our assessment from the bird's left wing.

In conclusion, the Derbyshire bird can be aged as a 1CY (first-winter).

Assuming this bird is a pure eunomus, which I have no reason to doubt – although I acknowledge the atrogularis/ruficollis/eunomus/naumanni complex seems to be a bit of a mess – the very dull overall plumage would suggest a female. Svensson (1992) states that there are "very slight differences between the sexes, and many are intermediated, difficult to sex". He points out two useful differences between the sexes: mantle/scapular pattern, and primary coverts pattern. His illustrations of a scapular feather show a well-defined black centre in males (as in the two birds discussed above) and a dark, rather than black, feather centre on females, sometimes reduced to just a dark smudge. The Derbyshire bird shows next-to-no contrast in the centre of the scapular/mantle feathers and sits right down and the female-end of the scale. The primary coverts in males are illustrated and are as discussed for the two birds above. In females, the primary-covert tips are dusky and diffuse, lacking the sharply contrasting black tips of males. The primary coverts of the Derbyshire bird (ignoring the feather fringed) appear almost uniform in their base colour, and again puts this bird right down at the female end of the scale.

In conclusion, I would call this bird a female.

Catching 'keets

It's not that often I get a ringing tick these days. My ringing is pretty much exclusively done with mist-nets and, other than rarities, there aren't many species left that are likely to blunder into a net and stick there. Indeed, most of the likeliest options for a new species in-hand are the sort that usually bounce out of passerine nets: Collared Dove, buzzard, umm, Black Woodpecker... Perhaps the most likely of the lot – at least ringing in London – was Ring-necked Parakeet, a species I can't say I was overly keen to add to my list. Sometimes you have no choice, though, and this morning this chap blundered into one of my nets:

 
 

I say chap. Actually, I have no idea if it's male or female. Butler & Gosler (2004) give a formula for sexing that involves wing length, bill length, and number of yellow feathers on the underwing. Frankly, just ringing it and taking a wing length was enough of a blood bath – parakeets have quite long necks and a big ol' hooked bill (with that, plus the from-the-centre primary moult, it's not overly surprising they now appear next to falcons in the list) and even when you have one in a ringers grip they can still turn around and give you a nasty nip, or four – and I didn't have enough fingers to spare to start trying to count the yellow feathers on the underwing!

 
No parakeets were harmed during this morning's ringing session. In fact, I go the feeling it rather enjoyed taking chunks out of my finger...

No parakeets were harmed during this morning's ringing session. In fact, I go the feeling it rather enjoyed taking chunks out of my finger...

 

As for the subspecies, well, that's anyone's guess. Consensus seems to be they're Indian (manillensis/borealis) but beyond that it gets tricky. A BB paper back in 1993 suggested birds were borealis on the basis of biometrics and bill colour (all red). However, birds I've examined in the field – and this one in the hand – all seem to show dark lower mandibles and sometimes a darkish tip to the upper mandible. Perhaps the subspecific composition of London's parakeets has altered over time and more non-borealis genes have been added to the mix. With a wing length of 171 mm, this individual seems to sit right in the middle the two Indian subspecies (but is out of the range for either of the smaller African subspecies).

At least the ageing was straightforward: the pointed tips to the outer primaries age the bird a first calendar-year (see Butler & Gosler 2004 for a comparison). There don't seem to be too many photos of parakeet wings around so, despite the pretty dire quality of this photo, I'll post it here as a bit of extra reference material for anyone unfortunate to enough to catch one of these themselves.

 
The apparent difference in shape between P5, 6, and 7 is just an effect caused by the placement of the feathers in the photograph.

The apparent difference in shape between P5, 6, and 7 is just an effect caused by the placement of the feathers in the photograph.

 

All joking about taking my fingers off and not wanting to catch parakeets aside, this species is not often ringed in the UK and – given their status as an invasive alien species – any extra data on movements could prove useful. Just over 2,000 have been ringed in the UK, of which only about 30 have been recovered.

Less bitey birds ringed included a Blue Tit (not often I say that), a few Great Tits, and a Continental-looking Robin. 

 
 

Birds of the Canary Islands – Eduardo Garcia-del-Rey (2015)

Here's a book review I wrote back in January. I held off from posting it then because, after my comments on Robins and Chats, I didn't want to become "that guy who posts negative book reviews"; but following my trip to Lanzarote I've been using the book again and I've suffered the same frustrations I encountered the first time around. It may well not be a positive review but, on careful reflection, it still feels like my comments are fair and a reasonable reflection of the product. Furthermore, word on the grapevine is that the same author has just signed a deal with Bloomsbury to publish a title on birds of the Canary Islands – whether that's a new title dealing with the avifauna as a whole rather than on a species-by-species basis or whether it will simply be a sexed-up hard-back version of this publication remains to be seen. Either way, I seriously hope Bloomsbury have got their fact checkers on standby.


Eduardo Garcia-del-Rey has done more than most to publicise the diversity of birdlife found in the Canary Islands and has a host of publications under his belt. His latest offering, Birds of the Canary Islands, is the pinnacle, representing more than 20 years of resource-gathering and literature-gleaning on the avifauna of the archipelago. The result is a weighty tome of over 900 pages covering “all 202 [species] recorded in the archipelago”. [Update: It is also the first in a series on Macarnesian avifauna, with a title on birds of the Cape Verde Islands due for publication this year]

The commoner species receive a more-or-less similar treatment: taxonomy, status, distribution, population, habitat, movements, breeding, conversation, and so on . Rarer species are included in a list at the back, with number of records broken down by island.

One species is conspicuous by its absence, if not by its presence on the SOC logo that adorns the front of the book: the Canary Island Black Oystercatcher. The species is not covered in the book at all and, while it could be argued that its extinct status means it is of little interest to modern-day ornithologists on the island, the claim that the book included “information from the last 215 years (1800–2015)” is at odds with the non-inclusions of the species.

The book is also billed as having “in the hand identification for every passerine species” but, as far as I can see, this extends to a selection of – often rather poor – in-hand photos for most (not all) passerine species. Accompanying captions are scant and presented in at least three different styles throughout the book. Moult information is given but for the majority of species simply states if a moult is complete or partial for the different age classes, most apparently simply lifted from BWP. It’s reassuring to see Fuerteventura Stonechat gets slightly more extensive coverage than the average but it would have been nice to see this same treatment extended to some of the other endemic taxa – especially give then author’s comments in the introduction regarding the establishment of a ringing programme to study ageing, sexing and moult of species not previously covered in literature.

Ageing and sexing of Goldcrest. Photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

Ageing and sexing of Goldcrest. Photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

Ageing and sexing of Goldcrest. This and the previous image represents all ageing and sexing material published for this species in the book. The shadow in the lower right photo is present in the published photograph and is not a result of photographing the printed page. Photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

Ageing and sexing of Goldcrest. This and the previous image represents all ageing and sexing material published for this species in the book. The shadow in the lower right photo is present in the published photograph and is not a result of photographing the printed page. Photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

As sole author, cartography, designer, typesetter, editor and, to-a-point, publisher (the author is the founder and managing director of the SOC), Garcia-del-Rey has certainly shown his dedication towards getting Birds of the Canary Islands published; but the one-man-band approach to the production comes at a cost: the English in places is in need of a good edit and the layout is in desperate need of a designer’s eye. The narrow inner page margins, for example, make it a challenge to read words closest to the spine, while the style of binding doesn’t give me much hope that the spine will withstand too much forcing open wide. Then there are some points that on the face of things seem rather minor but in actual fact make navigating through the book surprisingly difficult – things such as the lack of a species-name heading on the page or any clear indication in the font size and style where one species ends and another begins. And the indexing system: birds are listed alphabetically by their first name, such that the index runs from Abyssinian Roller to Yellow-legged Gull. Common Redshank is called simply Redshank and thus appears under R; but Linnet is listen under its “full” name and thus appears under C for Common Linnet. And then there’s Laurel Pigeon, which the author inexplicably called “Thermophile Pigeon” in the body text, but which is still indexed as Laurel Pigeon in the index (and not under T for Thermophile).  Mixed in amongst these English names are the scientific names, not italicised and thus surprisingly difficult to differentiate from English names when scanning down the list. Even when you've found the page number of the species you're looking for, you still have to battle with finding the page you need – there's a large swathe of the book where the page numbers are printed on the inside corner of the page, i.e. burried in the spine! I reiterate, these are relatively minor points but together they make a measurable difference to the ease with which one can use – and enjoy – the book.

Index, photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

Index, photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

References to Garcia-del-Rey (2011) are plentiful throughout this book. The often-referenced Gardia-del-Rey (2011) will be better known to most birders as Field Guide to the Birds of Macaronesia. You start to get the feeling that the reference is included sometimes just for reference’s sake, although in relation to habitat and status it’s perhaps justified. Where it does start to get into thin ice is in places like, for example, Blackbird taxonomy: “According to Garcia-del-Rey (2011), the subspecies carerae is not genetically distinct compared to the nominate.” Curious, I read the Blackbird entry in Garcia-del-Rey (2011): “Two races have been described for Macaronesia, T. m. azorensis and T. m. cabrerae, although recent mtDNA analysis found no basis for latter.” No further references are given. There must be a primary source for this data somewhere and for the author to reference one of his earlier works – which I’m absolutely sure is not the primary source for this genetic study – is, in my view, unacceptable and really does smack of self-referencing for the sheer hell of it.

Corn Bunting, photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

Corn Bunting, photographed from Birds of the Canary Islands by Garcia-del-Rey (2015).

It doesn’t take too much reading through to find other issues. For example, it’s stated that Barolo Shearwaters return to their colonies around March. I was involved in field work surveying and tagging birds returning to their colonies in late December, data which is in fact quoted later on in the species entry, so it’s clear that the author is aware of these studies. Looking for a typical page to show in the review, I opened the book and landed the Corn Bunting page  shown to the right. Even here, on a randomly-selected page, issues are apparent: the complete post-juvenile moult is stated as being "usual" for the family when in fact it is unusual (undoubtably this is a typo but it's an extremely unfortunate type that an editor would surly have picked up on). The fact there is no date attached to the photographs makes them of limited use (note also the differences in captioning style between this species and the above Goldcrests), and the lack of a location makes the sentence "no live biometric measurements of the bids from this Archipelago" hard to understand – was this bird photographed in the Canary Islands but the ringer took no biometric data at all, or was this bird photographed elsewhere? The taxonomy of the species also seemed to be a little confused as well but I had neither the time nor the inclination to investigate deeper.

To refer to Garcia-del-Rey as an enthusiastic amateur would undermine his status as an established ornithologist. Nonetheless, there’s an inescapable feeling that this publication sits in the category of “well-researched personal labour of love” rather than an authoritative scientific avifauna. There’s clearly a lot of useful information contained within its pages and the amount of writing time and resource gathering that must have gone into publishing this book shouldn’t be underestimate. However, for me at least, this book comes a long way from living up to the hype that the author has attempted to generate around its publication.

For anyone who has a particular interest in the archipelago’s avifauna, it’s going to be a useful addition to their bookshelf. I just can’t help but think it could have become an essential addition to all Western Palearctic birder’s bookshelves had it received some external input, not least from an editor with a keen eye for scientific rigour and a designer with a knowledge of page layout.

Seabirdin'

I'm kinda playing catchup here, but I said in my last post that I was going to do some exciting birding; so here is it –  a summary of four days staring down a telescope in Ireland and three days heaving my guts up on a boat 80 miles off Lanzarote...

Ireland was officially a work offsite. A strategy weekend where we purge ourselves of the distractions of London and instead distract ourselves with birding. This year's destination of choice was Loop Head, County Clare. And by Loop Head I actually mean Loop Head; our accommodation for the four days at the start of September was Loop Head lighthouse cottage.

 
Yes, I'm recycling Instagram photos on my blog #filter

Yes, I'm recycling Instagram photos on my blog #filter

 

Seawatching was, by Bridges of Ross standards, pretty average – though thousands of Manx Shearwaters, dozens of Sooty Shearwaters, and the occasional skua and storm-petrel were certainly enough to keep us entertained and happy between meetings. We thrashed the headland, the beaches and the "trees" a bit but with not much more to show for it than a Hen Harrier, some Wheatears, and plenty of Sanderling and Turnstone. Resident stuff included a family of Stonechats, a handful of Chough, and a Peregrine.

We also had regular sightings of a pod of Bottle-nosed Dolphins, which were feeding below the cliffs near to the lighthouse.

 
delfinas.jpg
 

Then I flew direct from Dublin to Lanzarote, where I met up with Marcel and the Lanzarote Pelagic Team for three days of at-sea birding on a small boat 80-odd-miles northish of the island. To cut a long and frankly rather unpleasant story short, I spent most of the first night and morning puking my guts up with intermittent periods of vomiting there after. Once I'd got a grip of my seasickness (lying perfectly still on the deck for a few hours was the answer... getting nice and sunburnt in the process), the birding could begin... First day highlights included Bulwer's Petrel, Wilson's Petrel, and some winter-breeding (Grant's) Band-rumped Storm-petrels.

Seas were rough on the second morning but we scored with White-faced Storm-petrels, more summer-breeding Band-rumped Storm-petrels, and some summer-breeding (Maderian-types; no Montiero's-types this trip) Band-rumped Storm-petrels. There's lots to be said on the matter but to give a very brief over-simplified summary: winter-breeding birds were morphologically quite consistent – thick-billed, square-tailed, quick thickset, and all in fresh plumage. Summer-breeding birds, identified by the fact they were actively moulting, were a bit more variable – most had thinner bills (than the winter-breeders) and you could convince yourself the tail was a tad more forked; they felt lighter in flight too (although perhaps some of this was to do with state of moult). No birds were as thin-billed or fork-tailed as would be expected for Montiero's. Some moulting birds, however, had bills that approached winter-breeders in thickness. Given that summer-breeding birds didn't seem to cluster into distinct morphological groups, I suspect it's just (considerable) variation within the same taxa rather than anything more sinister – but you never know...

 
Summer-breeding. Note the thin bill, the slightly forked tail...

Summer-breeding. Note the thin bill, the slightly forked tail...

 

Non-identification highlight of the trip was finding a feeding flock of several thousand Cory's Shearwaters accompanied by hundreds of Spotted and Short-beaked Common Dolphins and a couple of Bryde's Whales. It was just like in the wildlife documentaries; you know, where the shearwaters and the dolphins are going at the fish from all angles and then a whale pops up in the middle of them. There were also White-faced Storm-petrels bouncing about between it all, which was a particularly memorable vision given that it felt like this is what the bird's should look like in their "natural habitat" (er, rather than picking chum out of a rubber ring).

 
 

We didn't have much time on dry land – just a few hours either side of the boat – but Marcel did an expert job in getting us all of the interesting island species: Eleonora's and Barbary Falcon, Houbara Bustard, Berthalot's Pipit, Lesser Short-toed Lark, Trumpeter Finch, Barbary Partridge, Stone-curlew, degener Blue Tit, and other species that I'm sure I've forgotten to list.

 
The best Trump you'll see all November; although, despite the primaries, probably not the most eccentric [that's a moult joke; this bird has undergone an eccentric post-juvenile primary moult]. If only Marcel could have got us a bit closer... [that's also a joke, aimed at the fucker who shall remain nameless who constantly complained that Marcel wasn't able to get him close enough to the birds – including, I kid you not, this one!]

The best Trump you'll see all November; although, despite the primaries, probably not the most eccentric [that's a moult joke; this bird has undergone an eccentric post-juvenile primary moult]. If only Marcel could have got us a bit closer... [that's also a joke, aimed at the fucker who shall remain nameless who constantly complained that Marcel wasn't able to get him close enough to the birds – including, I kid you not, this one!]

 

Blogger's curse

The problem with having a blog is that you feel compelled to post things to it. After a long day in the field, writing a blog post about what I've just seen is – these days – low down my list of priorities, and leaving it a couple of days until I've got a bit more time makes it all feel a bit out-of-date; but then I feel bad for not having such an inactive blog page, and even worse for making empty promises about Quail moult and retained secondaries in cisticolas and things like that. So, in an attempt to bring some new content to this page, here's this quarter's collection of photos and words. See you all again in December. (Actually, I'm away soon and I'll hopefully see some good birds. So maybe I'll post something next month. Maybe.)

Bird log 27-08-2016

Thorpness, Suffolk
We thrashed the bushes around Thorpness old caravan park for a few hours today. Nice early autumn birding with some a flock of 'pseudomigrants'. You know, basically a tit flock made up almost entirely of locally-bred Long-tailed Tits but with a few Chiffchaffs, Willow Warblers and Lesser Whitethroats thrown in. They are undoubtably locals too but you can just about convince yourself that they could have come in on an easterly. A couple of Hobbies fell into the same category: the fact the baby was chasing one of the adults around for food slightly spoilt the migrant illusion.

Offshore one Gannet passed (migrated?) north and 13 Little Gulls were in the bay – 10 first-years and an adult. Little Gulls are always great to see and these came pretty close in. I even managed to phonescope them.

Regents Park, London
It was a lovely evening back in London so I walked partway home through Regent's Park, reading a few Canada Goose rings, doing some light-weight birding, and, erm, catching some Pokémon. I did make two interesting observations, one of which involved a Moorhen and the other of which involved some Greylags, both of which I'll write up for British Birds. I also saw some Egyptian Geese.

Swiss Cottage, London
Almost better than the Little Gulls, this evening I heard a Common Sandpiper flying over our flat in Swiss Cottage (inner-ish northwest London). There's something about migrating waders at night that made it quite an exciting flat tick. Oh and talking of exciting waders, I found a pratincole in Essex the other weekend. Sadly it was too far off to assign to species. By the time we got closer it was no where to be found, probably hunkered down behind a Lapwing or something, and there was no further sign of it in the two hours that followed. The record will have to be be submitted simply as "Glareola sp. (not Small).

Last minute Spain

I was going to head down to Portland for a couple of days last weekend (23/24), taking the train and staying in the obs. The obs was fully booked and, by the time I’d taken into account the cost of the train and the potential cost of a hotel nearby, I realised I could nip out to Spain for the same time at quite literally the same cost. So, Friday afternoon, I flew out to Girona where I met Marc Illa, then on to Aiguamolls where Marc had been ringing for the past couple of days. 

Aiguamolls is a magical place and this is the first time I’d spent time back there since I lived there for three months in 2010. Not much had changed; it was still packed with amazing birds – Black-winged Stilts, Whiskered Terns, Garganey, Curlew Sandpipers, Greater Flamingoes, Yellow Wagtails (iberae and some migrant flava), Squacco Herons, etc etc etc. At the rice fields we found a small flock of Stone-curlew and, bah, an Egyptian Goose.

 
 

Having reacquainted myself overnight with the Barn Owl that’s still nesting above the bedrooms in the house at El Mata, we headed off early to Palau at the north end of the reseve. This was, when I was ringing here, my “office” and, bar some of the trees being a bit higher, it had hardly changed. It was nice to be back.

Our target was Aquatic Warbler; there seems to be a not insignificant number that pass through here in spring. We didn’t catch any, but we did manage to ring a good selection of other reedbed species plus a few other bits and pieces. And yes, putting this blog post together I did realised every bird I have an in-hand photo of is brown...

Moustached Warbler

Moustached Warbler

Zitting Cisticola

Zitting Cisticola

Nightingale

Nightingale

Bastard Nightingale (true story – look up the Spanish/Catalan name)

Bastard Nightingale (true story – look up the Spanish/Catalan name)

Great Reed Warbler. This one's only a teeny-tiny one. They can get about 10% bigger.

Great Reed Warbler. This one's only a teeny-tiny one. They can get about 10% bigger.

Blackcap, female. What you often don't see in the field – or indeed in field guides – is the subtle rufous spot on the rear of the ear coverts on some female Blackcaps. Up close they're a really attractive bird.

Blackcap, female. What you often don't see in the field – or indeed in field guides – is the subtle rufous spot on the rear of the ear coverts on some female Blackcaps. Up close they're a really attractive bird.

Sightings while we were ringing included Pallid and Alpine swifts, Red-rumped Swallow, and a smart male Pied Flycatcher.

 
Red-rumped Swallow

Red-rumped Swallow

 

After a morning at Palau, we headed inland towards Marc’s hometown. I spent a bit of time on some nearby farmland while Marc nipped back to his place. The thing that amazes me most about Spain is the number and range of bird species you can find, and walking around this farmland really hammered the point home.

 
 

Imagine going to any old bit of arable farmland with some scattered trees, sandwiched between a town and a small industrial estate and with a small canalised river running through it. You look up; what do you see? Here, a quick scan of the sky produced a Peregrine, 100s of swifts, House Martins, Barn Swallows, a couple of Common Buzzards, and a distant Griffon Vulture. Some Bee-eaters were plooping away just behind the industrial estate. In the trees along the river, Melodious Warblers, Long-tailed Tits (taiti), Firecrest, Cirl Buntings, Serins, Song Thrushes, Blackcaps, and migrant Common Whitethroats and Willow Warblers. Corn Bunting territories numbered one every couple of 100 metres. There were Nightingales, Cuckoos, Crested Larks. Around a small pool there was a Little Grebe, a Wood Sandpiper, Zitting Cisticolas and a Great Reed Warbler.  

Undeniably, a lot has to do with climate and avian distribution; but where in the UK could you take a walk through farmland and see so many and such a variety of birds and species? Spanish farmland is, frankly, a bit of a “mess”. Field edges are ill-defined, farm buildings have holes in the roof, marshy patches are scattered here and there. As you flick another fly off your arm or step over another ants' nest, you begin to realise how much more life there is in this "messy" farmland compared to the depressingly neat and sterile British countryside.

 
 

Late afternoon, we headed to a large stretch of arable farmland a short distance from Marc’s town to catch Quail.

Quail-catching with a view – Monserrat in the distance.

Quail-catching with a view – Monserrat in the distance.

Quail are, with the right set-up, particularly easy to catch and within ten minutes we’d caught two males – a second-year and, erm, well… These were my first Quails in-hand and to be honest I found them to be a bit of a mindfuck. A quail’s life is basically a repeating series of moult, breed, migrate, and it seems to be the case that birds are sexually mature within four months of hatching. The second bird I think is probably a first-year but the state of moult would suggest it must have hatched at least 8 weeks prior to being caught. Are Quail already breeding at the end of February in (?)Africa? Here are some pretty profile pics; the spread wing shots deserve their own blog post.

Quail 1

Sunday morning we tried – unsuccessful – to catch a pair of Black-eared Wheatears at a site close to Marc’s town. Both were carrying rings and were presumably the same pair that were ringed the last year but confirmation would have been good. If they’re returning year-on-year, they might be suitable for a study with loggers.

 
Male Black-eared Wheatear through the rear window. A really stunning bird... not that this photo shows that!

Male Black-eared Wheatear through the rear window. A really stunning bird... not that this photo shows that!

 

The birds were clearly wise to the traps though and, despite perching on the fence posts directly above, refused to take the bait. After an hour of waiting it was time to head to the airport and back to the UK.

I still go birding... sometimes

My nan asked me while I was home over Christmas, “are you still as keen on birds?” I think the slightly veiled meaning of the question was to ask if I’d moved on to something a bit more “normal”, like cars or football or drinking. Had she been a bit more savvy she could have asked, “do you actually go birding anymore?”

As it happens, I went birding twice over Christmas/New Year – more on that below – but it’s taken some five weeks before I've managed to get out birding again. Fiona, David Howdon and I headed out west to Thursley Common yesterday. It was blowing a gale but that probably helped with locating the Great Grey Shrike. It showed well, if briefly, in a (relatively) sheltered area around the base of one of the hills. The white is rather limited, so there's no fun to be had trying to make it anything other than ‘melanopterus’; and it appeared to be an adult, supporting the theory that it’s a returning bird.

We took a walk around most of the rest of the site although the wind was clearly keeping avian activity to a minimum: some Coal Tits and a charming pair of Stonechats were the best of the six other species seen.

Great Grey Shrike

Great Grey Shrike

European Stonechat, male

European Stonechat, male

On the way back to west London we called in at Staines Reservoirs. It was still blowing a gale… and the causeway at Staines Reservoirs is hardly the most sheltered place. Two Black-necked Grebes were showing well in the (relatively) calm water behind the tower on the south basin.

 
Black-necked Grebes

Black-necked Grebes

 

The north basin was stuffed full of ducks: Tufted Duck, Common Pochard, Eurasian Teal, Eurasian Wigeon, a drake Northern Pintail and a drake, er, plain old Gadwall. Pochard numbered at least 500, close to 80% of which were male. I’ve submitted my results to the Duck Specialist Group Common Pochard sex ratio assessment.

One of the pochard stood out as being remarkably dark and my first thought was that it might have been a Common Pochard x Ferruginous Duck hybrid. On closer inspection, I wasn't so convinced. And by "closer" I mean squinting down my scope for a little longer trying to keep all three of the tripod legs on the ground. Viewing was...

 
 

...choppy.

Apart from the dark body, the rest of the bird looked fine for a male Common Pochard, including the bill pattern, and I wonder if this individual is melanistic or something.

 
 

Talking of aberrants, and going back to my Christmas birding, these, I believe, are the feet of a Polish Whooper Swan:

 
 

It's from Iceland; but I mean Polish in the sense of “Polish Mute Swan”, or leucistic. Or semi-leucistic. Or something. Maybe, given the dark mottling on the legs, this is only semi-Polish. The more I learn about plumage aberrations the less I feel I know…

I saw the bird just after Christmas, feeding in front of the swanky new hide with a bunch of other Whooper Swans. Although there’s some variation amongst juveniles, this one stood out as being considerably paler. Compare it with the bird that’s peaking into view on the left here (which, as with all of the others I looked at, had black legs/feet):

 
 

I remember seeing an adult Whooper Swan many years ago that had yellow legs. I wonder if this individual will grow up to have the same.

Martin Mere is always good value for a winter's day's birding. In addition to the swans, there were some Ruff around, a Barn Owl, and nice close-up views of assorted wildfowl, including this Ross's Goose “of unknown origin” hanging out with the shelduck.

 
Ross's Goose

Ross's Goose

 

And as if that wasn't enough plastic for one afternoon, here's an East Asian superstar line-up: two Black Brants, a pair of Falcated Ducks, and a Baer's Pochard.

 
 

Martin Garner passed away just over a week ago. At the start of last week, my Facebook news feed consisted almost entirely of posts dedicated to his memory; a good modern-day measure of how much he meant to a lot of people. His Birding Frontiers ethos had (indeed, has) become an established and much-celebrated part of birding.  Even this blog post has some Garner influence to it: his Challenge series: winter is where I checked that what I was saying about the Great Grey Shrike wasn't utter tosh. 

I met Martin for the first time many years ago at Spurn. I was in the hide trying to work out the age, sex and race of a Snow Bunting, directing my out-loud thoughts to a friend who was sat next to me. I was aware of someone sitting on the other side of me who had started listening in to the conversation. We spoke and I introduced myself. “You know who I am,” he said to me. Then, with a cheeky smile, he said “You didn't like my book!” I blushed a little. He was right, I didn't like his first book (in contrast to his most recent two, which are great). I needn't have worried though. He held no bad feeling whatsoever and we joked about the matter. I held a lot respect for Martin after that first meeting.

Friends of mine will tell you that I often found Martin's approach a bit gung-ho – but that was very much the character of Martin's work. I respected Martin a lot for his willingness to try things before anyone else, to suggest identification features that may have been nothing more than a hunch, and to get new thought-provoking ideas “out there”. There's absolutely no doubt that Martin's enthusiasm and drive has made the current European birding scene a richer and better place, and he'll be sorely missed. The seed he planted in so many birders – the drive towards “always discovering” – is a fitting legacy.

Balancing the books

It’s all too easy to shout about the things that don't match expectations while quietly enjoy the things that do, never publicly giving them the praise they deserve. With that in mind, I thought it was worth balancing out my comments on Robins & Chats with a few positive thoughts on some other books from (relatively) recently.

First, another in the Helm Identification Guides series: Wildfowl of Europe, Asia and North America by Sébastien Reeber. It’s a great book, well written, comprehensive, and clearly extensively researched. Little details, like carefully written photo captions, help to add even more value. It’s how a Helm Identification Guides book should be. If you’re only allowed to ask Santa for one expensive book this Christmas, I suggest this one.

Undiscovered Owls by Magnus Robb et al. is everything you’d expect from The Sound Approach Team. Magnus’s writing style makes it eminently readable while at the same time a presenting a phenomenal amount of information – and not just on vocalisation, even if that is the main focus of the book. A couple of the species splits might be a bit liberal (“For the sake of argument we will treat each [of the three Macaronesian barn owl taxa] as species…”) but there’s no shortage of information to allow the reader to make up their own mind on the matter, and no attempting to hide where evidence might actually be lacking (“…but let’s be clear; their sounds differ only subtle and none has been the subject of a thorough genetic study”). Tell Santa you’ve been a really good boy/girl this year and point out that if China can end their one child policy then he can end his one expensive book policy.

Martin Garner’s Challenge Series: Winter is a great follow-up to last year’s Autumn book. Both books give a really nice overview of the some of the tougher-to-identify taxa and I use them fairly often as a quick go-to to remind myself of the most important features – and usually find myself learning something more in the process. At £17.99, you can return those awful M&S character socks and grandpa slippers your auntie bought you, persuade your mum to buy the credit voucher off you, and use the cash you’ve just gained to buy this one yourself.

And if your interest extends beyond birds, Steven Falk’s Field Guide to the bees of Great Britain and Ireland looks, after a quick flick through, like it should prove to be an excellent book. It’s illustrated by Richard Lewington, which already makes it great. There won’t be any bees for a few months now, so put this one on your birthday list or something.

Robins and Chats – some comments on moult

It always pains me to complain about a book. I heard recently someone say, "any author of any book should be congratulated just for getting it published. Many people start writing a book but very few finish." – and it's true. Peter Clement should be wholeheartedly congratulated on the publications of Robins and Chats, the latest Helm Identification Guide. Chris Rose deserves equal praise for the plates, a lot of which I saw first-hand at the Birdfair. They're every bit a stunning as you'd imagine, particularly the rubythroats.

The problem I have is that my interests are, by my own admission, fairly narrow. I don't care about a species' behaviour, nor am I particularly worried about its status or distribution. When I buy a book like this, I head straight for the moult and ageing sections. I dream of opening the pages and finding something similar to Sylvia Warblers (also part of the Helm Identification Guides series): beautifully presented primary source data, the result of years of field work from the authors. What one gets with Robins and Chats, at least for the species I've thus far checked, is a re-write of BWP, Jenni & Winkler, and other material, mashed together in such a way that it becomes messy, ambiguous, and hard to sift through even for me. 

I've so far only dipped into a few species that I'm already familiar with – and in that respect I don't claim this blog post is anything like a full review of the book – but I'm already alarmed at how many errors there seem to be. Yes, they're small errors that only the most pedantic of readers are going to get worked up over, but they are still errors. Take for example the description for post-juvenile moult in European Robin: "Partial post-juvenile moult of head, body, lesser and median coverts, and variable number of greater coverts (usually innermost three, but possibly all in S Europe), also some or all tertials, and starting late May to mid-August, completed late July–early October". Ignoring the fact it's a pretty clunky sentence, I don't think I have ever handled a robin that has moulted any tertials. That's not surprising really given that Jenni and Winkler reported that 99.8% of the 8,499 birds in their study had moulted no tertials. Yet here, Robins and Chats implies it's the norm to see at least one tertial moulted on every bird following post-juvenile moult. 

And Common Redstart, "[Post-juvenile moult] affects head and body feathers together with lesser and median coverts and some or all primary coverts, in nominate all greater coverts may be retained from juvenile plumage or up to three inner coverts are replaced". Again, clunky; and, again, erroneous. Common Redstart, to the best of my knowledge (pers obs from a couple of hundred birds handled, and from published material) never moults primary coverts during post-juvenile moult. Robins and Chats references BWP and Jenni & Winkler within the Common Redstart moult section but neither of these make any mention of primary covert moult either. Of course it could be the author's own personal data but, if it is, it's a pretty casual way of describing what would be a radically different moult strategy to anything previously reported – and it would be interesting to know which population they were studying to get such surprising results. My feeling is, though, it's just wrong.

There's mention of primary covert moult in the Whinchat moult section, too. This, to be fair, is from previously published material (referenced here as BWP but in fact from an earlier publication that is quoted in BWP). However, it's pretty ropey and likely erroneous. My main issue here is that the claim of a small number of birds with moulted primary coverts (five from a sample of 30 in just one study) is taken out of context. The fact that Jenni & Winkler reported data from over 200 birds, none of which had moulted primary coverts during pre-breeding moult – and that the remainder of the BWP text reports a much more limited moult with no mention of primary covert moult – seems to have been swept under the carpet. The result is the misleading statement that "some" second-year (erroneously referred to as first-year in Robins and Chats) Whinchats moult all of their primary coverts during the pre-breeding moult.

Red-flanked Bluetail is described as moulting "some or all of tertials and tail feathers" during post-juvenile moult. The statement is made in regard to the overall post-juvenile moult of the species, thus implying it is the case in every individual. In reality, Hellström & Norevik (2013) found that just 1% of 397 had replaced up to nine tail feathers following post-juvenile moult and 1.5% had moulted up to all three tertials. So really, "tertials and tail feathers generally retained from juvenile plumage, may be replaced in very small number of individuals (Hellström & Norevik 2013)" would have been a much better way of putting it. What makes things even worse is that Robins and Chats doesn't reference Hellström & Norevik here; instead, it references BWP, which makes no mention at all of tail feather replacement! 

Further, the Bluethroat entry erroneously refers to post-juvenile moult of primary covers (again! I don't get the obsession with moulted primary coverts).

You'll be pleased to know I didn't have any issues with the Black Redstart moult entry...

And that's it. They are literally the only six moult sections I've read, five of which have errors (or, at best, misleading information). So what about the photo captions?

It's not unreasonable to expect birds in photos in a book like this to be correctly aged (or, in cases where they can't be, no age to be written at all). Forgive me for continuing to harp on about Sylvia Warblers but compare some of the photo captions there – carefully written mini case studies on the bird in question – with the minimal captions in Robins and Chats (below, screenshotted from Google Books).

European Robin, from Clement & Rose (2015). Robins and Chats,  Bloomsbury.

European Robin, from Clement & Rose (2015). Robins and Chats,  Bloomsbury.

Note the robin in the top right: "probably first-winter". Probably first-winter?! I wouldn't mind so much if this was a photo of a Rubeho Akalat or similar, where ageing characteristics aren't known or photos of correctly aged birds are hard to come by; but this is a European Robin!

At least in this case it was prefaced by "probably" (and it is a first-winter); there are multiple cases where the ageing is simply wrong. Two of the five male Black Redstart labelled as an adult are second-years; one of the "adult" Common Nightingale is a second-year, while the bird labelled "first-winter" looks distinctly adult-like to me; all three of the perched "adult" mourning wheatears (one lugens, one persica and one halophilawarriae is not photographed) are first- or second-years – and this is from checking through no more than about ten of the more familiar species.

To be honest, I haven't really read any further. I'd rather not know what other mistakes are lurking amongst other species entries. I fully acknowledge that few other people are going to lose any sleep over these mistakes and probably there's lots of stuff in the other sections of the book that is correct and well written; but it shakes my confidence in using this publication as any sort of authoritative reference. What happens if I need to find out the moult strategy for a species I don't know much about, like a Pied Bush Chat or an Eversmann's Redstart? Can I trust what I read?

What really makes me sad is that I doubt more than a few people will really notice. Or care.

Is this a book worth having? It's an attractive publication, the plates are very nice, and it appears to be the best single source for an overview of the family. Certainly, the general reviews I've seen have been full of praise. It's not a book I regret buying and I'm sure it will prove useful for lots of things; but, for moult and ageing, I've got a horrible feeling most of my references will be preceded by contra.

Robins and Chats by Peter Clement and Chris Rose Published by Bloomsbury, 2015, ISBN 9780713639636 RRP: £60.00

References
Cramp, S. (ed.) 1988. The Birds of the Western Palearctic vol. 5. Oxford University Press, Oxford.

Hellström, M. & Norevik, G. 2013. Further comments on the ageing and sexing of the Red-flanked Bluetail. British Birds 106: 669–677.

Jenni, L. & Winkler, R. 1994. Moult and Ageing of European Passerines. Academic Press, London.

Shirihai, H., Gargallo, G. & Helbig, A. 2001. Sylvia Warblers. Christopher Helm, London.

Plumage variability and field identification of Manx, Yelkouan and Balearic Shearwaters

A paper that I've been involved in for some time now, authored by Marcel Gil Velasco and Guille Rodríguez, has just been published:

Gil-Velasco, M., Rodríguez, G., Menzie, S. & Arcos, J.M. (2015). Plumage variability and field identification of Manx, Yelkouan and Balearic Shearwaters. British Birds 108 514–539

Three medium-sized Puffinus shearwaters breed in Europe: Manx P. puffinus, Yelkouan P. yelkouan and Balearic Shearwaters P. mauretanicus. These three, considered a single, polytypic species until relatively recently, can be difficult to identify in some situations, notably in a vagrant context. This paper presents a detailed review of the plumage variability of the three taxa; combined with an understanding of structural differences and flight characteristics, this should provide a sound basis for the identification of problematic individuals.

 

 

The plate on the left is my favourite from the paper; Marcel and Guille did a fantastic job of finding photographs that compliment each other – like this pair do. 

There's also some superb artwork by Martí Franch, which can be viewed at high resolution on the British Birds website.

Falsterbo & Barred Warbler

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I spent Thursday of last week to Monday of this at Falsterbo, Sweden. I'd hoped to do some "live" blogging while I was out there, but a big storm on Saturday morning took out the internet and the 4G phone signal.

Pretty much exactly five years to the day, I arrived at Falsterbo for the first time – as a visitor. I rolled up to Flommen and got to see a Merlin in the hand. Thursday morning, at Flommen – as a visitor once again – we caught... a Merlin; only the sixth to be ringed at the observatory and the first since that bird I saw in 2010. It was a first-year male. I'll try and post a few more instructive photos once I've had time to sort them out but for now you can enjoy the below shot, ignorant of a) how far I'm having to stretch my arm to get the whole bird in and b) how much my right index finger is bleeding after the bird took a nibble (you can see some evidence of that on my left wrist).

Other bits and pieces ringed included a Red-throated Pipit, a Bearded Tit, a Grasshopper Warbler, Water Rail, and other stuff that I'm far too blasé about like Marsh Warbler and Icterine Warbler.

Not having to put the nets up in the morning (thanks Marc, Timmy and Zsombor!) meant having energy to do some birding in the day, usually joined by Ollie Metcalf who had also come to visit for the weekend. A few Red-breasted Flycatchers and two Tawny Pipits were the best of the Passerines – along with Common Redstats, Spotted and Pied Flycatchers, a mix of Sylvia warblers, Tree Pipits, Yellow Wagtails etc – while there was a good passage of several hundred Honey Buzzards on Thursday and Common Buzzards and Black Kites on Monday.

It was an all-too-brief visit but extremely nice to catch up with everyone, including all those who were at the Falsterbo Bird Show over the weekend; and thanks to all the observatory staff, with an especially big tack så mycket to Marc for the always stimulating discussions and to Justin Beiber for just being an all round great guy.

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It wouldn't have been overly surprising if I'd seen a Barred Warbler during the past week – although they are surprisingly scare at Falsterbo – but I certainly didn't expect to be heading west from London to see one. We went on a quick office twitch this afternoon, along with our (as yet non-birding) software engineer, to Staines Moor. After a short while, the bird shows well in the "Brown Shrike bushes". Here's a video grab from a Coolpix P900... taken at 83x optical zoom.

Moths

It's that time again. And by "that time", I'm not sure if I mean the July birding doldrums or back living in London. Either way, most of my recent contact with wildlife has come in the form of moths. Some of them very nice, actually.

The other week I was up at The Nunnery in Thetford, the BTO's HQ. A group of us joined some of the research staff for an evening of (attempted) Nightjar ringing. We saw plenty, and there was quite a bit of activity early in the evening, but windy conditions meant we didn't manage to catch any. 

The first Common Glow-worms of the season were out. I had never realised that it is the female that glows. She uses the light to attract males, which can fly but which don't glow.

The same night, we set a moth trap at The Nunnery. In the morning it was heaving with moths: hundreds of moths of over forty species. Highlights – i.e.  the pretty ones – included Burnished Brass, Scarce Silver-lined (below left) and Small Elephant Hawk-moth (below right).

Closer to home, we've been running a moth trap on the roof of the office in Acton. It has caught a surprisingly variety of species, including a migrant Red-necked Footman.

More exciting – at least from an entomology point of view – are a colony of Clepsis dumicolana that we've discovered breeding on the ivy at the office front door. They're one of only three known colonies in the UK and were probably imported – and then overlooked for years – on the plant. There are more details on the NatureGuides blog.

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nteresting moths haven't been confined just to the office. Back at home, this Bordered Straw came fluttering in through the kitchen late one evening. It's a migrant from the continent, and a very attractive moth too.

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Of course I've been up to plenty of other stuff in London, including visiting some of the museums. I'm going to say something that may get me shot: the Natural History Museum is, in my opinion, one of the most boring museums around. The content is, well, dated and disappointing. And as for the plastic T. rex...

One of the relative highlights for me was the leaf-cutter ant colony. Not this summer :(

At least the building is magnificent, and this photo of the central hall is one of my favourites that I've taken over the past few weeks.

I'll go my best to get out into the field a bit more over the autumn otherwise I run the risk of becoming one of these "desk-bound ornithologists".

First genetically confirmed Eastern Subalpine Warbler for Sweden

An adult male Sylvia cantillans sensu lato was ringed at Falsterbo Bird Observatory on 19 May 2013. Plumage, biometry and calls suggested an Eastern Subalpine Warbler S. cantillans sensu stricto, recently given species status by the Swedish taxonomy committee. As of 2012, there are seventy accepted Subalpine Warbler records in Sweden but none has been assigned to any of the three new splits: Western (inornata), Eastern (cantillans) or Moltoni’s (subalpina) Warbler. A genetic analysis of the Falsterbo bird showed it to be Sylvia cantillans albistriata, the first of this taxon to be unequivocally identified in Sweden.

Menzie, Gil-Velasco & Collinson (2015). First genetically confirmed Eastern Subalpine Warbler Sylvia cantillans for Sweden. Ornis Svecica 25 40–44

A pdf of the full paper is available to download from the Publications page.

Dippers on the Don

Plenty of Dippers on the River Don in Aberdeen yesterday, which was apt really since we managed to not see the nailed-on Harlequin Duck.



Some consolation (stress on ‘some’) was had in the form of an Otter, which gave amazingly good views as it fed on the opposite bank of the river.


Actually, apart from the whole not seeing the duck thing, and the fact I was horribly ill with man flu, it was a nice day out. Mind you, I would say that: I spent most of the day asleep in the back of the car! With thanks to Chris and John for doing the driving...

Sudan Golden Sparrows, Bir Anzarane (Western Sahara)

I've just returned from an excellent week of birding in Western Sahara with Oliver Metcalf, Tim Jones, and Jonnie Fisk. One of the undoubted highlights was a flock of Sudan Golden Sparrows at Bir Anzarane.

Following a report of a single male Sudan Golden Sparrow with Desert Sparrows at a drinking site near to Bir Anzarane on Friday 30 January, we travelled to the site on Monday 2 February with Mohamed Lamine Samlali from Association Nature Initiative (A.N.I.) and counted a minimum of 28 Sudan Golden Sparrows. At more-or-less the same time as I counted 28 on the fence by the drinking site, the other three members of our party counted at least 17 on the other side of the settlement buildings. However, there was clearly some crossover between the groups of sparrows and since no coordinated counting was carried out, we consider it safest to consider the final count as “minimum 28” – in reality, there may very well have been some 40 or more Sudan Golden Sparrows present on site at the time.


The site is located near to an area with land mines and birders wishing to look for the birds should contact A.N.I. to arrange travel and access.


At least 31 birds were again present on 6 February when Mohamed visited the site with a group of Belgian birders (Pieter-Jan D'Hondt, Joachim Bertrands, Simon Vyncke, Sander Bruylants, and Robrecht Debbaut). Additionally, the settlement resident reported that the birds had been present for "a couple of years" and that his cat regularly caught "one or two each day"(!); so it appears that the birds may be resident or largely-resident in the area.

Barolo Shearwaters on the Canary Islands

At the end of December, I spent two weeks on the Canary Islands. The main reason for my visit was to help Marcel and the rest of the Universidad de la Laguna/Canarias con la Mar Project team with an expedition to put PTT (GPS) devices to up to four Barolo Shearwaters. As much as it may sound like a fun holiday in the sun, it was actually bloody hard work. The original plan was to head out to a colony on one of the northern islets but prolonged rough sea conditions meant we couldn't get out there. Multiple nights at several "mainland" colonies gave us some good data in the form of singing birds, and, with a thermal-imaging camera, we were able to watch some night-time behaviour for the very first time. However, we did not managed to catch any shearwaters (thought we did catch one Grant’s Storm-petrel). 

On Thursday 18th we finally managed to get onto the Montaña Clara islet, where a colony of Barolo Shearwater is (relatively!) easily accessed in the volcano crater. We had two nights before we had to leave again and four PTTs still in need of a home. Working on the islet is extremely tough: all water etc needs to be carried on, and the study site is a tough 90 minute hike up a ridge and down into the crater. 

On the first night, we heard several birds but again didn't manage to catch any. It looked like it would be the same story on the second night until, just a few hours before dawn, we caught one! The bird was ringed, measured, a genetic sample taken, and a PTT fitted.


The PTT transmits real-time data and, by the time we were back on the mainland later in the morning, we could already see that the bird had left the islet and headed northwest. After ten days of hard slog and frustration getting to that point, it was extremely satisfying to see that our hard work had paid off. 


Pre-ringing. The feet and legs were an amazing bubblegum-blue and black.


PTT fitted and ready to go.

You can view more information about the project and the tagged bird – including some of the PTT data – here. For anyone interested in hearing more about the ten-day expedition I was involved with, I will be giving a short talk to the RSPB Liverpool local group following their AGM on Monday 20th April 2015.

Happy New Year/Happy old Woodpigeon

...although in actual fact it's not *that* old.


This bird, in the garden this afternoon, was ringed as a second-year in 2011, which makes it four-and-a-half-ish. Still a long way from the 17 year 8 month record but nonetheless interesting that is had stayed in the garden for so long (it pops in from time to time throughout the year).

Species nova

Dear Sirs,

It is with great excitement that I write of the events of the night of Saturday thirteenth of December 2014. On an expedition to the Canary Islands – a Spanish colony located in the Atlantic Ocean some miles off the Western Saharan coast – I joined a group of locals as they visited the breeding colony of a bird they call "paiño". These locals were rather civilised, knowing as they did how to cook using a stove heated using natural gas. They procured a meal of tinned beans and a local sausage known as "chorizo". Accommodation was a cave located near to the sea. We consumed our meal of beans and "chorizo" near to the cave mouth.

At approximately 22:30, I caught sight of a "paiño" making a series of swift turns in flight around the entrance of the cave. It reminded of the Common Stormy-Petrel, a species I am familiar with from the northern United Kingdom. Using my battery-operated torch, I illuminated the bird, at which point it alighted on volcanic rocks some seven yards from where we were located. I sent my man forth, a young Spaniard with an impressive knowledge of the Kingdom's avifauna. With nothing but his bare hands, he secured the bird. 


The bird was examined in some detail. It was an adult female, sexed by the cloaca distended following egg laying. I find it peculiar that this species should be breeding during the winter months, though the climate in this location is much more favourable than that encountered by the more northern Common Stormy-Petrel

In appearance the bird was sufficiently similar to the Common Stormy-Petrel, except for: it was larger (the wing measured five-and-one-quarter inches), possessed a narrower white area below the saddle, and held a bill of thicker dimensions and stronger bite. It appears to be the case that, whilst this form is obviously known to the natives of these islands, it has not yet been formally described by the scientific community. I propose this bird be known as the Grant's Stormy-Petrel.

Also of note is our continued observation of the Barolo Little Shear-Water, a scarce breeder on the cliffs of the Canary Islands.

I am indebted to Juan Bécares for the photograph of my Spanish boy assistant in action.

Cows at Burton Mere



Distant cows, some pink-feet, a young male Hen Harrier, an oversized adult male Hen Harrier, and a very nice Christmas dinner in the Boat House in Parkgate. That pretty much sums up a pleasant afternoon on the Wirral.

#Harry