The presence of Mediterranean gulls is expanding across Scotland, with what is thought to be the first ever record of breeding of the birds in the country. 

This year saw the first ever hatching of Mediterranean gull chicks in Scotland, although they did not survive long enough to start flying. 

The species, which was once a rare sight in the UK, is now breeding in increasing numbers, particularly on the southern coasts of England. 

Mediterranean gulls have increasingly begun venturing further north, with single gulls infiltrating Scottish gull colonies and pairing with both black-headed and common gulls. 

Two pairs of mediterranean gulls which had settled within a black-headed colony successfully hatched chicks in Forvie National Nature Reserve in Aberdeenshire, which is thought to be a record. 

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Daryl Short, Forvie Nature Reserve Officer, said: “While we have seen visiting Mediterranean gulls at Forvie before, we were very surprised to see two pairs of two-year-old birds settle in the black-headed gull colony this summer, with each pair successfully hatching chicks."

The Reserve believes the reason the chicks did not survive was likely due to a drought at the time which would have made earthworms, an important part of the gull diet, hard to source. 

The birds were also fairly young, and their inexperience of breeding would have further lowered survival chances.

“Despite the pairs not successfully fledging any chicks, this was still a really exciting development for Forvie as the species expands its breeding range northwards and we are looking forward to seeing what happens in 2024,” said Mr Short. 

The Mediterranean gull core breeding population originates in the Black Sea but the species has been registered in Britain as early as the 1980s, the same decade in which they began expanding westward.

The shift further westward and northward from their origins can be explained by climate change, the creation of new wetland habitats and better protection of colonies in those countries.

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As well as notable breeding of the Mediterranean birds, wildlife experts are also pleased with record breaking figures on the black-headed gull population. 

The breed has had a positive year, with 2,428 pairs recorded in Scotland and 1,353 fledged ones, which are new records. NatureScot described this as “heartwarming” given that in the most recent Seabird Count census, the black-headed gull had declined by three quarters compared to the previous recording. 

Another bird to have had a particularly good year was the Eider, a type of large sea duck, which thanks to a high duckling survival rate had its best year since the turn of the century. 

The spreading of avian flu meant other breeds did not have as successful a year as the gulls. Sandwich terns were the worst affected bird, with a high chick mortality rate of 75%. 

The flu also hit arctic terns, with an 18% adult mortality rate - high for a bird which tends to be long-lived and slow to reproduce. 

Scotland’s avian flu task force, which is led by NatureScot, is preparing for next year by continuing its work to assess and better understand the impact of avian flu and ensure there are appropriate measures in place to support the recovery of species impacted by the outbreak.