Pomarine Skua Stercorarius pomarinus
Generally scarce autumn passage migrant, although occasional larger movements, mainly September to November. Rare in winter and spring and exceptional inland.
A scarce or sometimes fairly common passage migrant, most being seen between late July and December, with peaks usually in September-October. Daily counts may be small, and their movements are often associated with other skua species. In the historic archives, 1879 and 1881 are mentioned as years of exceptional numbers. Later, few were recorded 1936-1957, possibly due to reduced seawatching. In the modern era 1985 and 1988 produced exceptional passages with 50-100 on several dates and about 300 birds reported in each year. Since the millennium, illustrative data for Pomarine Skua numbers were taken from various annual reports and the following data refer to annual totals for site peak monthly counts: these ranged from 50 in 2017 to 500 in 2018 with an average of around 200 per year. January-February usually sees a few birds offshore but records from March-July are rare. It is usually the latest migrating skua seen in the county and migration doesn't really get under way until September. Autumn migration (as a proportion of total annual records) is split August-December as follows: August (1%), September (5%), October (54%), November (13%) and December (14%). The largest single flock reported was 188 at Gibraltar Point on October 27th, 2018, and there were at least 90 elsewhere on the coast that day. Two days later on October 29th, 100 were reported off Witham Mouth and 90 along the coast. Another big movement occurred on December 2nd, 2014, when 81 were reported off Huttoft and a further 40 off Gibraltar Point. Prior to these two events the largest day count had been 91 off Huttoft on September 29th, 1988. It is interesting to note that 58% of all peak counts occurred on just three days of the 5-year period! Also check out the article "Overland autumn skua passage from The Wash" on the Arctic Skua webpage.
(Account as per new Birds of Lincolnshire (2021), included September 2022; updated August 2023)