Saturday 10 February 2018

The Staines 'American' Horned Lark re-visited 9th February 2018


Last year, towards the end of November, what is thought to be a Horned Lark from America was found on the concrete wastes of Staines Reservoir in Surrey. I and quite a few other birders went to see it, although interest amongst the wider birding community was more muted. The lark remained from the 19th to the 28th of November before disappearing, as vagrant birds such as this are prone to do.

Little more was thought about it until, to everyone's surprise it was re-found on the central causeway of Staines Reservoir on 22nd January this year and there it has remained to the present day. Perhaps because of the widespread discussion about its identity and origin that had occurred during its absence many more birders now decided, following its rediscovery, that it was worth going to see, as potentially it is likely in the future to become a bona fide species and separated from our very similar Shore Lark. On a more mundane level it also has the romance attached to it of being a very rare transatlantic vagrant.

Moth, my erstwhile birding pal had never seen an 'American' Horned Lark or indeed a Shore Lark which are one and the same species at the moment and I was quite keen to have another look at the lark as it would now be in a more advanced stage of its transition from winter to spring plumage and well worth studying for future reference. So on an alternately sunny then cloudy but consistently windy day of bitter cold we set off for Staines Reservoir which lies close by the village of Stanwell and London Heathrow Airport. Apart from the inevitable traffic hold up on the M25 around Heathrow we made good time and arrived at about noon to park the car in an unofficial layby at the western gate of the reservoir 

It was sheltered as we walked up the incline to gain the central causeway that runs between the huge North and South basins of the reservoir and which is also a public footpath running for a mile from the western end of the reservoir to the eastern end at Stanwell. Once we reached the causeway it became all too apparent that there was to be no hiding place from the bitterly cold wind sweeping in from the northwest over the cold watery expanse of the northern basin. We hunkered down into our warm clothing and set off down the causeway.

There were already one or two birders scattered along the causeway and on reaching the first birder I enquired about the Horned Lark and was told it had just flown along the bank of the southern basin and been lost to view. We walked back along the causeway checking the concrete shelving of the southern reservoir bank but could not find it. Then a shout came to us on the wind telling us one of the birders had found it feeding with some Meadow Pipits.

We made a rapid about turn and soon joined the birder who had relocated the Horned Lark which was scuttling along, as is their mode of feeding, on the concrete shelving covered in extensive patches of green moss or lichen of some sort with tufts of grass liberally scattered about, growing up from the cracks between the concrete.





The lark spent much of its time digging vigorously into the soft moss or tufts of grass looking for invertebrates and was constantly on the move, hardly ever  still. It did not like the more open areas and it was noticeable how it would cross these at speed to where it obviously felt more secure, partially hidden amongst the tufts of grass and other low growing vegetation. 



This southern side of the reservoir was comparatively sheltered from the full force of the wind although the bird was still buffeted about by errant gusts sweeping down and over the exposed bank.The lark flew every so often, for some fifty or so metres along the bank and we followed it until by a series of short flights it had reached almost to the western end of the causeway.





From our position near the end of the causeway the Horned Lark remained visible for some time before it took to the air and flew very high up into the sky, being tossed around by the strong wind in the process  and was lost to view. It had looked like it was headed much further east  when it was flying above the bank so we walked the whole mile to the eastern end of the causeway looking for it and found precisely nothing. We then walked back, joined by another birder. We flushed half a dozen Meadow Pipits which flew along the bank to land again but it was only after walking back about three quarters of a mile that we found the Horned Lark. It had obviously doubled back un-noticed by us and as before it was scuttling around on the soft spongy moss  and between tufts of grass, still digging its bill into the moss and the grass tufts.









As before it flew along the bank for another fifty or so metres before landing and we duly followed. Finally it seemed to settle, again near the western end of the causeway and although constantly active as it fed did not fly again. 

To get a photo was difficult as the railings guarding the reservoir got in the way to a degree and the lark's  rapid movements also created some technical issues with the camera but every so often the planes rising from nearby Heathrow caused it to pause in its feeding so it could check with cocked head that no giant predator was about to descend on it and this was a chance to record it when it was still.


This time I was more prepared and informed about the subtle plumage variations that would indicate that this was a true Horned Lark from America and not just an aberrant Shore Lark (Shore Lark is our confusing name for Horned Lark. They are currently, as I said earlier, one and the same species). Although this is not the place to go into a detailed  plumage description the aspects of its current plumage I observed were as follows:

Compared to my last visit its overall plumage looked more colourful and contrasting, if that is possible on a basically streaked brown bird with a striking black, yellow and white patterned head.There was a warm pinkish tone to the flanks and wing coverts unlike the greyish tones on 'our' Shore Lark which is meant to be an indication of an 'American' Horned Lark but one always has to consider the light conditions as this can affect one's perception.

This image shows to good effect the pink tone to the lesser and median
coverts on the bird's partially open wing which is considered an
indicator of an American Horned Lark




It was the distinctive head pattern that made it look so conspicuously and obviously different to a Shore Lark. The patterning was more defined now with a thin indistinct black line on the forehead, another thicker band of black running from bill to  eye and then downwards on the cheeks, encompassing the pale yellow chin and throat and finally an even broader triangular band of black at the join of the throat and breast. The marked contrast between a pale yellow throat, white forehead, supercilium and greyish white ear coverts was even more marked than the last time I saw this bird.


Note the pink toned flanks and mantle and pure white belly. Other
supposed indicators of an American Horned Lark.
The breast was also pale with noticeable and numerous wavy lines of dark spots running down it and I noticed from the photographs I took that a vestigial black horn was appearing on each side of the crown, though they were hardly visible. It is believed that the bird is a female so I  guess the plumage is never going to be as bright as a male and certainly the horns will not be as prominent as on a male.

One thing is certain, this bird looks like no other Shore Lark I have seen but it will take considerable study of the intricate plumage details of this bird for it to have a chance of being accepted as a Horned Lark. There are however many good photos of this bird now available on social media so hopefully they will act as a resource that can be studied and bring this bird's identity to a conclusion one way or the other. 




Both Moth and myself were getting a severe working over from the relentless wind as we watched the Horned Lark and it was becoming uncomfortably cold for both of us. After an abortive but brief  search for a drake Scaup we decided to leave, having given the Horned Lark almost two hours of our attention.  Having worked at Heathrow for many years prior to moving to Oxfordshire I knew from bitter experience that the nearby M25 around Heathrow on a Friday afternoon was no place to be.

We set off for Oxfordshire and none too soon, as the M25 Motorway was already nearly at a standstill. 

For those of you wanting more information on the subtle plumage differences and races of Horned Lark please click on the link below


















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4 comments:

  1. Thanks for another great trip, Ewan! (Btw, I'd never seen any type of shore/horned lark before!)

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    1. Delighted to hear that Moth. On to the next wherever that may be!

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  2. Thank you for this very informative entry. I saw the lark yesterday, and appreciated being able to read up about it before and after my trip.

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    1. So glad it was of help to you and thank you for reading my blog.

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