Thursday, 17 October 2013

Cattle Egret

 I think that I will soon have to remove the word "novice" from the descriptor above. I am starting to notice things that even surprise me.

Today I was searching the salt marshes on Sheppey having made yet another failed attempt to get a picture of the Lesser Yellowlegs at Cliffe Pools. There were a few distant Little Egrets and nothing much else but then there was one bird that did not look quite right. I do not carry a scope so my technique is to take a picture on the 700mm set up I use and then to blow it up on the back of the camera to see what I've got. Its not much use on hazy summer days but works quite well as we move into the crisper, clearer winter days.

My initial shot below showed an Egret but the shape looked wrong, the head was too big and rounded and there was no sign of a dark bill.


View through 700mm lens


Blowing up the shot on the back of the camera confirmed a yellow bill but it was clearly not a Great White Egret as it was too small. That only leaves a Cattle Egret. Initially I had my doubts. I would not expect to see it on a salt marsh. It is an insect eater and in this country would normally be seen around cattle.  A  quick check in Collins confirmed the identification ( I hope! ).


Digital enlargement of the shot above.

 I would have liked a better shot but it was quite mobile and stayed distant so all my shots suffer from being huge crops and over sharpened.


Cattle Egret in Flight

Cattle Egret


There were lots of other waders on the mud flats but very few that were close enough for a picture.


Grey Plover
and one still showing the remnants of its summer plumage
Ringed Plover


 There were also a number of Raptors around. Peregrines, Buzzards, Marsh Harrier, etc but the only picture I managed to get was yet another Kestrel.


Kestrel


And finally a few shots of a Wren hunting insects in the fading light.


Wren
There is one around here somewhere.

There were plenty of birds around today although they were mostly the usual suspects and very few were close enough for pictures. Still Sheppey is a new area for me and I enjoyed searching out new birding locations. On the way off the island I went past the entrance to Elmley NNR. It was getting late and its a big site to get around so I decided to leave it for another day. Bad mistake. This evening there is a report of nine White-fronted Geese on the reserve and I haven't managed to see one yet this year.

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The identification of the Cattle Egret in this blog was questioned and led to the publishing of a BIRDGUIDES Webzine article, The article and comments are set out below for completeness.

Throughout October and November 2013, a Cattle Egret was reported regularly (although intermittently) from the Isle of Sheppey, in north Kent. The bird, first reported on 3rd October and last seen on 29th November, was generally to be found on the saltmarsh at Harty Ferry, at the south-east end of the island. Despite its being around for several weeks, we received no images directly here at BirdGuides — unusual for such a long-staying scarcity. However, towards the end of last year, Marc Read emailed me a link to Sussex birder Martin Peacock's blog, asking me to have a look at the egret featured in his post from 17th October. On opening it up and looking at the photos of the bird in question — the Harty Ferry bird no less — it was instantly clear that something was wrong. Though labelled as a Cattle Egret, there appeared to be multiple plumage and structural features at odds with that species, although it didn't really seem to fit any of the European or African egret species. I got in touch with Martin to express my thoughts, and he responded with the following:
"The pictures below are of the 'Cattle Egret' seen regularly around Harty Ferry on Sheppey back in October. It was my first Cattle Egret, so I spent some time checking the identification, photographing and learning about the bird. Although I was happy at the time that it could not be anything other than a Cattle Egret, I could not find any pictures on the web that showed examples of black legs and yellow feet as you would find on a Little Egret. The shape of the lower jaw also seemed to be different to the pictures that I was looking at but I put this down to the bird being a juvenile. Finally there was the fact that it was feeding on a saltmarsh along with other Little Egrets, when I would have expected to find it in pastures, feeding around cattle, or in similar habitats.
The shots were published on my blog back in October and I thought nothing more of it. However, since that time I have received queries suggesting that this may be a Little × Cattle Egret hybrid. I have searched the web but although this hybrid is recognised I cannot find any details on what the resulting bird would look like. This is getting a bit beyond my current levels of expertise and I wondered if there is anyone out there that can help me with the identification...
Finally, my apologies for the quality of the pictures. The bird was about quite distant and the pictures are heavily cropped."

Above: the 'Harty Ferry egret', both at rest and in flight, 17th October 2013 (Photos: Martin Peacock).
So, what is it? For starters, it seems quite clear that this isn't a Cattle Egret. Perhaps the most striking feature is the yellow feet (as in Little Egret), but there are other differences that point away from that as a diagnosis. For example, the bill is comparatively long, thin, and posseses a dark tip, while it also appears rather long-necked for that species. The legs are also rather long and spindly. Could it be an aberrant Little Egret? Personally, I'm not sure: facially, it looks quite Cattle Egret-like with those bright yellowish lores and the predominately yellowish bill (which is perhaps a little shorter than on your average Little Egret). Similarly, the neck, though longer than a typical Cattle, looks quite thickset and rather less 'snaky' than you'd expect in a Little Egret. This, along with the quite plump body and shortish legs, give it quite a dumpy, stunted feel.

Composite showing (left to right) Little Egret, the 'Sheppey egret' and Cattle Egret in similar poses, demonstrating the apparently intermediate structure and appearance of the Sheppey bird. Photos of Little Egret (John Freeman) and Cattle Egret (Tom Victory) from the BirdGuides Iris galleries.
Another species with a yellow bill is Intermediate Egret but, like Cattle Egrets, they have black (not yellow) feet and are larger, longer-necked and more elegant-looking than Little Egrets (not smaller and short-necked as in the Kent bird). White-morph Western Reef Egrets would show paler, greenish legs and a duller bill, as well as a different structure. The bird is also clearly not a Great White Egret.
It is at this point that we mention the 'H' word for the first time. Hybrids between herons, egrets and their allies are rare but certainly not unknown. The Handbook of Avian Hybrids of the World lists Cattle Egret as having hybridised with both Little Blue Heron and Snowy Egret in the USA, and with Little Egret in both Europe and Africa. Furthermore, examples of Cattle Egrets apparently hybridising with Squacco Heron have been recorded in the wild in Spain and Italy (see here and here), while an apparent Cattle Egret × Night Heron has been recorded in captivity in Germany (see here).
Therefore, displaying characteristics seemingly intermediate between Cattle and Little Egret, could the Sheppey bird be a hybrid between the two species? Based on what we can see in Martin's photographs, such an assumption certainly seems reasonable. We'd love to hear your views and opinions on the bird — feel free to leave any comments in the section at the foot of this article!


Comments

a lesson for all in checking a rarities true identity. how many people must have seen this and just 'ticked' without thinking. photos show very clearly its not a simple cattle and H seems right
   Mark Welfare, 10/01/14 14:08Report inappropriate post Report 
#2
According to Collins....Western Reef Egret (Egretta gularis) can have an all yellow bill, legs greenish grey to black, with yellow toes, clearly it can be cosmetically variable, also size ranges between 55-68cm. (garzetta/Little Egret) 55-65cm. with gularis at the upper range wings can stretch to 112cm as opposed to 106cm for garzetta. Cheers
   Ken Murray, 10/01/14 21:01Report inappropriate post Report 
#3
Well spotted Marc. I wonder how many people saw this and didn't question the ID?
   Andy Lawson, 10/01/14 22:23Report inappropriate post Report 
#4
Hybrid Little x Cattle looks the most likely. It is obviously not a proper Cattle Egret and to be honest I am surprised that it was reported as such for so long.
   Steve Lister, 11/01/14 12:55Report inappropriate post Report 
#5
Why not simply a Little Egret, with an individual fault in the complex mechanisms for controlling the production and accumulation of melanin. Perhaps, with the substitution of a carotenoid-based bill colour?
   Colin Selway, 12/01/14 14:23Report inappropriate post Report 
#6
Perhaps worth remembering that juvenile Little Egrets can look like this http://www.birdguides.com/iris/pictures.asp?v=1&f=365422 Of course this isnt a juv but individual variation can occur, what did these birds look like when they fledged!
   Richard Ford, 15/01/14 00:17Report inappropriate post Report 
#7
On the Western Reef v Little point Ken Murray raised - it should perhaps be noted that the tip of the bird's bill appears to be decurved. Normally regarded as a distinguishing characteristic between these two easily confused species.
   kev roy, 15/01/14 17:34Report inappropriate post Report 
#8
A breeding plumaged Cattle Egret was present in North Kent last spring and was seen on Higham Marsh, Cliffe and finally Northward Hill close to a Little Egret colony............
   Paul Larkin., 15/01/14 17:38



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