A new species is added to the list of birds breeding in Northamptonshire as Mediterranean Gulls nest for the first time at Stanwick Gravel Pits
Mediterranean Gulls have been appearing with increasing frequency among Black-headed Gulls breeding in the Nene Valley – particularly within the well-established Summer Leys colony. This appears to be a recent phenomenon, principally involving single birds which are apparently not sexually mature. Most remain for only a short time during spring but in 2015, a second-summer was discovered in the Summer Leys colony on 18th March, remaining there until 29th June. During this period, it established and held territory, continually displaying to the local Black-headed Gulls. This was repeated in 2016, with another second-summer visiting the colony for only a short duration on 20th-21st March. However, two adults appeared there little more than five weeks later, on 28th April, before relocating the following day to the Stanwick colony, where they were seen again on 11th-12th May. There were no subsequent sightings.
Fast forward to this year, 2017 and 5th April, when a pair was displaying among the Black-headed Gulls at Stanwick, after which they promptly disappeared. On 24th April two were again present – both wore BTO rings and one sported a black leg tag ‘SA30’, which has not yet been traced to source. Again, they were not subsequently reported but then two – amazingly a different pair – arrived in the Black-headed Gull colony on Rotary Island at Summer Leys LNR on 3rd May. Appearing settled, they remained difficult to observe in the island’s vegetation until 5th May.
The following day, 6th May, what was assumed to be the same pair appeared in Stanwick’s Black-headed Gull colony, where they were observed copulating and defending territory.
Nest construction ensued and eggs were laid, subsequently hatching, with the young visible within the colony. It was after this that fortune took a turn for the worse. During the first week in June the young had disappeared – assumed to have been predated by the local Lesser Black-backed Gulls – and by the end of the week both adults had also abandoned the site. Not a positive outcome for a first breeding attempt but, as this species continues to increase in the UK and indeed breeds in Cambridgeshire, we can surely look forward to further attempts in the future.
Thanks to Steve Fisher for providing information and to Bob Bullock for images.