Migration blog (20th-26th May)

With high-pressure keeping our weather relatively settled in the last 7 days, migration has continued unabated with good arrivals of many common migrants. An easterly airflow and some rain meant a few scarce birds were also thrown in for good measure.

Spotted Flycatcher is a typically late-arriving species, and the last week saw an increase in reports as this delightful bird made it onto several BirdTrack lists, with many glad to see ‘their’ birds back for the summer.

spotted_flycatcher_reporting_rate_may_2022

Other typically late-arriving migrants include Turtle Dove and Nightjar. Reports for the former are on par with recent years; let us hope they have a successful breeding season. Don’t forget to add your records of Turtle Dove to BirdTrack along with any breeding evidence, so their population and distribution can be monitored.

Some observers were lucky enough to find a day roosting Nightjar. These can be found in some rather odd places during migration, with one bird found roosting on a branch right outside a bathroom window and another trying to remain hidden on the edge of a birdbath!

Many of the Ringed Plover seen in May will be of the tundrea race that breed in Arctic Russia.  

As many wader species breed in the far north, mid-late May is the peak period for these birds to stop off across Britain and Ireland on their northbound migration.

Reports of Turnstone, Dunlin, Grey Plover,  Sanderling, and Ringed Plover all increased in the last week and will continue to build in the next couple of weeks. Many of the Ringed Plover will be of the tundrea race that breed in Arctic Russia, and are slightly smaller and darker than those that breed in Britain and Ireland.

Temminck’s Stint is a scarce passage migrant and last week saw a spike in reports, most likely due to the southeasterly winds pushing birds towards Britain and Ireland.

These same easterly winds were also responsible for some of the scarcer species seen during the week with Great Reed Warbler, Red-Footed Falcon, and Broad-billed Sandpiper all being recorded - and all having been predicted in the last migration blog. 

A scattering of other scarcities included Golden Oriole, Bluethroat, Bee-eater (including a flock of 17 in Suffolk), and Red-rumped Swallow. The stand out rarity was a Brown Shrike at Spurn, one of only a handful of spring records.

Species focus - Roseate Tern

Roseate Tern is one of our later-arriving summer visitors. Typically, the first birds are seen in early May, and numbers build in the following weeks, with peak movement along our coasts in the latter half of the month. Any tern flock is worth scrutinising for one of these stunning species. Their whiter plumage and dark bills are good identification features to help separate them from their commoner relatives.

It is our most marine tern, and is very rarely seen inland. It spends the winter months along the coast of the Gulf of Guinea, and there have been several ringed birds seen and found on the beaches of Ghana. Very little is known about the precise wintering area of Roseate Tern which breed in Britain, or the routes they take to get there; however, they are thought to winter on the coasts of several West African countries, migrating some distance offshore between their summer breeding grounds and their wintering areas.

It is estimated that around 100 pairs breed in Britain, but the most important breeding colony in Europe is to be found on Rockabill, Co. Dublin which holds in excess of a thousand pairs.

Looking ahead

The high pressure that has been keeping the weather relatively settled across much of Britain and Ireland has slipped away and the coming week looks to be more unsettled, with periods of wind and rain.

At the weekend, we will see light south to southwesterly wind across most parts - this shouldn’t adversely affect migration, with species such as Swift and Spotted Flycatcher still likely to arrive. Waders, including Turnstone, Ringed Plover, Little Stint, Grey Plover, and Sanderling will also continue to head northwards, and could be found at inland sites as well as coastal locations.

However, as we progress through the week the wind direction switches, bringing rain and strengthening westerlies for many parts. This will likely slow migration, as many passage species will be pushed towards the near continent.

Reaching the end of the week, the forecast is much better with lighter south to southeasterly winds and little or no rain. These are good conditions for species typically seen towards the end of May such as Marsh Warbler, Bluethroat, Red-necked Phalarope and Tree Pipit. Most of these will be from populations that breed much further north, but in the case of Marsh Warbler, they could be potential breeders. This species is covered by the Rare Breeding Birds Panel and can be severely affected by disturbance during the breeding season, so be cautious of putting news out if you are lucky enough to find one. 

The latter half of May is also good for a suite of rarer species, and in the past Western Orphean Warbler, Trumpeter Finch, Oriental Pratincole and Slender-billed Gull have all been seen in the last couple of weeks of the month, and would be a welcome addition to many a birder's list.