Bobolink – 1999

Dolichonyx oryzivorusBobolinc – vagrant

At the end of September 1999, south-west Wales had experienced a spell of strong to gale-force westerly winds, following the hurricane which east-coast North America had experienced.  We on Skokholm Island knew it was inevitable tht at least one “yank” of some description would be unfortunate enough to be blown across the Atlantic, but nothing appeared on Skokholm, as usual.  So we were resigned to the fact that it would not be us who would see such a bird, especially since it was now two weeks on and we were experiencing light easterlies and clear skies associated with a high pressure system.

On the 13th October, after a morning of doing paperwork in the observatory buildings, Theresa Purcell and I decided to have a sandwich lunch at the lighthouse and do some sea-watching at the same time.  However, we had walked just halfway along the main track across the island, which Teresa spotted a bird on the ground in a grassy clearing among bracken.  Despite Theresa possessing good bird identification skills, she felt the need to ask me what it was, whereupon I replied “Meadow pipit”.  Obviously disgusted in my lack of faith in her abilities, she exclaimed “That is not a meadow pipit” and I realised that I was looking at the wrong bird.  The individual in question flew up onto the top of the bracken and in the first split second that I saw it, I thought “aquatic warbler”, but upon seeing more than the obvious crown and mantle streaks, it was very clear that this was no warbler.  It was most obviously a bobolink, a North American bird!

After the initial shock, followed by taking it all in and releasing a few restrained screams of delight, I ran all the way back to observatory to make a few phone calls.  Too out of breath to use the phone, I picked up my camera and video camera, desperate to obtain photographic evidence, and ran back.  I needn’t have worried, Theresa had stayed with the bird which was obligingly sitting in the top of the bracken in the sunshine, contentedly eating craneflies.  Theresa made the necessary phone calls, while I took a long look at our bird.  Juan, Simon, Rob and Shirley crossed from Skomer and just managed to see it before dusk.

Skokholm is home to 46,000 pairs of Manx shearwaters, an estimated 20% of the world population, and is therefore peppered with fragile burrows.  Not an ideal place for a “twitch” and the fact that a boat does not freequently visit means that getting people across is difficult.  However, given the obliging nature of the bobolink and that it seemed content not to move any great distance away from a convenient viewing spot, the Skokholm and Skomer Conservation Advisory Committee decided to spread the news.  Subsequently, then other people saw the bird in what was the first official twitch on the island.  Thankfully it was viewed and greatly admired from the footpath, so none of the many burrows were threatened with trampling.  A flighty bird during the breeding season would probably necessitate a different decision.

Description:

General appearance and structure: First impression was “aquatic warbler” Acrocephalus paludicola, due to the crown and mantle streaks and general coloration of buff and brown.  Following further viewing, it was seen to be a rather large, upright, bunting- or finch-like bird, with a large bill, long tail and long primary extension.  Its pale lores and lack of obvious dark coloration along the lower edge of the ear coverts gave it a very bright facial appearance.  At times it hid in the bracken and moved along the ground, appearing somewhat corncrake-like, due to general plumage and bare parts coloration and its behaviour as it stretched its neck to look around.  In flight the tail was slightly fanned and showed obvious pointed tips to the feathers.

Plumage: head very distinctive, with a pale, whitish-buff central crown stripe and dark brown lateral crown stripes.  Pale buff supercilia and a brownish eye stripe behind the eye only, extending to the rear edge of the ear coverts and running just a short way down them whilst becoming very narrow.  No obvious moustachial stripe, quite unlike female yellow-breasted bunting Emberiza aureola. The centre of the ear coverts was buff.  Lores pale, upon close inspection seen to have a bluish-grey coloration.  Chin and throat the brightest part of the whole plumage, a whitish-buff and very obvious at a distance in sunlight.  The nape was more buff-coloured.

Upperparts: Back generally buff with darker streaks.  Mantle with two cream-buff streaks running vertically, edged with darker feathering.  In certain positions the pale streaks formed two inverted “V”s, the outer branch half the length of the main, inner ones.  General feathering of the scapulars was dark-centred, pale-edged.  Median coverts brightest part of wings, broad pale whitish-buff edges.  The other wing bars were far less distinct.  Tertials were, with the exception of the upper right feather, dark brown with a narrow whitish border; the other had a broad buff edge, evidently a fresh one, thus aging the bird as a 1st winter. The primary feathers were dark brown with narrow pale borders.  The rump and upper tail feathers were, as much of the back feathering, dark-centred with pale buff edging.  The tail was similarly coloured, the feathers noticeably spiky, this being particularly prominent when the bird flew overhead, silhouetted against the pale sky.

Underparts: The throat was the most noticeable feature at a distance, being particularly bright buff-cream.  The breast and belly were slightly darker buff but still generally pale as were the thigh feathers.  There was an obvious line down the centre of the breast where feathers overlapped.  The flanks had some darker streaking. 

Bare parts:  The bill was a pale pink, with a hint of darker blue-grey on the culmen and along the top of the upper mandible.  The eye was dark, black-brown, with a narrow white eye ring, most noticeable below the eye.  The legs and feet were pink.

Voice: a rather soft metallic “picc”, mainly uttered in flight at a regular interval of about one second, also heard when it was disturbed, as it flew up onto a bracken vantage point to observe what had disturbed it. Theresa heard it first and described it as a “rather less musical chaffinch-like pink” This is the description given in some of the books we subsequently referred to.

Behaviour: At first the bird was rather bold, allowing us to approach to about three metres distance.  It was clambering about among the top of the bracken fronds, which were mainly brown and withering at this time.  It frequently flicked its rather heavy-looking tail, with a slight downward movement before a far more pronouced upward flick.  It was regularly catching and eating craneflies which were abundant among the foliage. Occasionally it flew away, never more than about fifty metres and landed in other bracken patches, but inevitably returned to the original area by undertaking another flight.  Each time it flew it called.  As the afternoon of the 13th October wore on, the bird became less obvious, spending more time among the bracken, climbing about at half the stem-height, moving from frond to frond.  The moving vegetation was used to relocate the bird.  On the following morning, 14th October, despite twelve people scanning the top of the bracken, it wasn’t seen.  The wind had increased ESE 3-4.  It was finally located by accident as it was almost stepped on.  It flew a short distance onto the bracken, and called a few times before flying off again to its favourite patch.  It then remained hidden for long periods, occasionally showing its head and shoulders to an appreciative audience but did, thankfully, sit out in the open on occasion, particularly as the breeze decreased and it became warmer.  During its periods of skulking, it would occasionally stretch its neck up and look around, appearing very corncrake-like.  Tail-flicking was only occasionally seen.

Graham Thompson

Pembrokeshire Bird Report 1999.

More about the Bobolink in Pembrokeshire