Ring-billed Gull (LBRC)

Despite the number of British records standing at nearly 2000, 1958-2018, this remains a vagrant in the county. The first record was a 2CY bird in July-August 1988 and there have been just four more, most recently at Trent Port Wetlands, Marton in 2019. Although ‘ex-BBRC 1988’ it remains a tricky species to identify for some and it may be overlooked if occurring with large congregations off gulls on the coast or in the Wolds. A common species across North America, it prefers fresh water on migration and occurs inland more often than other species of gull, but its overwintering habitat includes coastal sites as well as inland reservoirs, lakes, landfill sites and conurbations. White and Kehoe (2019) showed that there has been a decadal decline in British records since 1990 with annual mean totals of 77 (1990-1999), 54 (2000-2009) and 17 (2010-2017).  However, there is huge variability between years and in 2019 27 birds were reported with 15 thought to be returning birds and 12 being new arrivals, one of these being the one-day 2CY bird at Trent Port Wetlands.

Finder’s report: Ring-billed Gull at Bagmoor, July 24th, 1988, first county record

by G. P. Catley.

Note: This account is based that which appeared in the Lincolnshire Bird Report 1988. The species was ex-BBRC by 1988 when there had been nearly 600 British records and in the 1987 report it was noted that the removal of this species from the list of rarities considered by the Committee will considerably reduce postage costs, the wear and tear of MJR's (M. J. Rogers) typing fingers and the not inconsiderable gnashing of Committee members' teeth!  

Circumstances

On July 24th, 1988, a joint family day out led Andy Sims (ACS) and myself to Bagmoor in a search for two yellow-legged Herring Gulls (Larus argentatus michahellis at the time) which John Harriman (JH) had seen there earlier that week. During the summer and early autumn large numbers of Lesser Black-backed Gulls regularly use the flooded area at Bagmoor for bathing and loafing and small numbers of Herring Gulls and Great Black-backs join them with large numbers of Black-headed and rather fewer Common Gulls, both of the latter species being mainly 2CY birds.

Arriving at Bagmoor late morning on a fine and sunny day we began to scan through the assembled gull flocks in search of yellow-legged Herring Gulls. Whilst looking through a small party of Lesser Black-backs with my 27x60 ‘scope I came across a smaller gull with pale grey mantle, white head and neck mottled brown, and old faded brown wing feathers. But what was instantly striking was the deep and prominent bill, which was dull horn-yellow with a well-marked black subterminal band.

Since 1975, searching for, but seldom finding, scarce gull species has been one of  my major interests in the county, mostly in the winter months. With the increasing number of Ring-billed Gulls being recorded in Britain since the mid-1970s, I began a regular scrutiny of the thousands of Common Gulls which frequent the Grimsby Docks-Cleethorpes foreshore every winter. I can thus claim some extensive experience with all ages, plumages and variations in plumages and bare part patterns in Common Gulls at all times of the year. Thus, having seen three Ring-billed Gulls in other areas of the country and with my experience of Common Gulls I immediately suspected that the Bagmoor bird was a Ring-billed. The fact that it was in faded 2CY plumage, in midsummer and more to the point, in Lincolnshire made me look rather closely before been suggesting the possibility to ACS. He quickly located the bird in question and by pure coincidence JH arrived as we were beginning to put together a full description. JH and one other fortunate visitor to the site that morning also saw the bird. The Ring-billed Gull stood with the Lesser Black-backs for some time before flying away and landing next to a Common Gull of the same age, which made for a useful comparison, and several Black-headed Gulls. When it sat down amongst them it was invisible and when we left it was still present but could not be found later that afternoon. It was reported again on a few  dates during the next week, and I saw it again on August 3rd which as far as I am aware was the last occasion on which it was seen.

Description

Structure – obviously larger and more bulky than Black-headed Gulls and slightly more so than Common Gulls, most notably about the head; only about 20% smaller than some Lesser Black-backed Gulls.

Head – profile similar to Lesser Black-backed with a sloping forehead and thick-set neck; head usually held hunched on neck but when alarmed was stretched up high and then looked rather long-necked in contrast to Common Gulls. Head and neck whitish but ear coverts, crown and nape all washed with buffy-brown and with darker brown streaking on the crown and old brown blotches on the nape and round the lower neck forming a half collar when seen from the front.

Plumage – underparts white. Mantle, back and scapulars all pale grey of similar tone to Black-headed Gull, with a thin whitish line along the edge of the lower scapulars. Amongst the wing feathers, one old, faded pale brown tertial was present with a very narrow paler tip. Greater coverts also faded brown centred with broad, pale creamy, bleached edges. Rest of flight feathers all faded pale brown (all remnants of 1CY plumage). Tail whitish with a broken, broad, faded subterminal band and some central tail feathers had been moulted.

Bare parts – bill much thicker and deeper than any Common Gull (1CY and 2CY often have deeper-looking bills due to the dark tipped pattern, cf. Glaucous Gull) and showed a pronounced gonys. Usually looked dull, horn-coloured but in sunlight had a distinct yellowish-ochre tinge – a prominent wide black band crossed the bill near the tip extending back along the cutting edges of the mandibles; the extreme tip was horn/ochre. Eyes looked dark with obvious whitish crescents above and below, but in good light the iris already looked paler, an indication of the change to second winter. A dark brown furrow or eyebrow extended over the eye. Legs looked long in direct comparison to Common and Black-headed Gulls, dull greyish in colour, seen to be slightly tinged with yellowish in good light.

Later observations – by August 3rd it was further advanced in moult with more missing tail feathers and flight feathers and more obvious pale grey scapulars. On both occasions the Ring-billed Gull was fairly inactive, roosting with the other gulls, but it did make aggressive gestures towards Black-headed Gulls, with neck raised and bill wide open.

This is the first fully acceptable record of Ring-billed Gull in Lincolnshire and is not unexpected with the rapid increase in records in Britain since 1980 in particular. There is still a very obvious west and south coast bias to the records and there have been very few Yorkshire records, and as yet not a single one in the heavily watched neighbouring county of Norfolk.